CLPS 0450 Final Exam Questions + Concepts

Anterograde vs. retrograde memory

Anterograde: after the brain damage, retrograde: prior to the brain damage

Tone-deafness (congenital amusia)

Congenital amusia is present at birth disorder in pitch processing and music perception that affects ∼4% of the population

Explicit vs. implicit memory

Conscious versus non-conscious recollection

Declarative vs. non-declarative memory

Declarative memory is the explicit, conscious system that allows us to consciously recollect events and facts (personal and world knowledge). Nondeclarative memory is accessed without consciousness or implicitly through performance rather than recollection (such as motor and cognitive skills).

Familiarity

Familiarity is typically thought to involve a fast and automatic recognition process that allows for recognition of a previous experience without retrieval of details from the encoding episode

Who is H.M.? What effect did the bilateral temporal lobectomy have on his cognitive functions? Why didn't neurologists realize the profound effect this procedure would have?

HM is the classic medial temporal lobe amnesic patient. Patient HM was studied by Scoville & Milner (1957). HM was a 27-year-old motor winder with seizures since age 10. His epilepsy was very difficult to treat, which justified the experimental surgery, even though they did not know the origins of the seizures. He was given a radical bilateral temporal lobectomy. The surgery was a success in that it stopped the seizure, but after the surgery, he could not remember meeting people even a few minutes later, but could remember everything up to his surgery. In other words, his ability to acquire new memories was disrupted. The report from the experimenters said, "subsequent recovery was uneventful apart from the grave memory loss." In the 8 cm area of neural tissue drawn on the left, when they did a scan of him later, it was only 5 cm bilaterally, but the rest of it had atrophied so it was nonfunctional. After the surgery, the patient's IQ score increased slightly. In terms of his memory quotient on the WAIS test, his score decreased to two standard deviations below average. Scoville and Milner's previous patients were all psychiatric patients, which led them to not recognize the profound impairment following surgery before their surgery on HM. HM became one of most-studied amnesic patients.

Uniqueness point

In recognition of words in isolation from context, the point at which enough phonetic information has been heard to leave only one word-form as a possibility

Phonological lexicon

Lexical phonology is an approach to phonology that accounts for the interactions of morphology and phonology in the word building process

Describe the general taxonomy of the different long-term memory systems. How are they assessed behaviorally? Which types of memory seem to be particularly impaired (and which relatively intact) in amnesic syndrome patients? In Vargha-Khadem's young neurological patients? In semantic dementia patients?

Long-term memory is split up into declarative (personal and world knowledge that we have access to, split up into episodic and semantic memory) and nondeclarative memory stores (knowledge to which we have no conscious access, such as motor and cognitive skills). Nondeclarative memory includes classical conditioning (learning to associate neutral stimuli with something desirable by the subject over several trials) and perceptual priming (exposure to one stimulus influences a response to a subsequent stimulus, without conscious guidance or intention). Nondeclarative memory is intact in amnesic patients. (perceptual priming is fine, procedural learning, motor and cognitive, is fine, and classical condition is okay depending upon how you do the contingency). In terms of declarative memory, anterograde episodic memory is impaired. There is a temporal gradient for episodic memory deficiencies in that amnesic patients have more difficulty recalling memories closest to the time of brain injury. Semantic memory is debatable—it may depend on the extent of damage. If damage is specific to the hippocampus, it is intact, but if brain damage is more extensive, patients will show evidence of impairment of semantic memory. Butters & Cermak (1986) were trying to assess whether PZ showed a temporal gradient for retrograde memories because the Albert et al. (1979) study of Korsakoff patients showing a temporal gradient for retrograde memories had been critiqued by saying that the temporal gradient might be due to the patients not encoding properly during their alcoholism rather than a true temporal gradient of more remote retrograde memories being recalled better than recent retrograde memories. Patient PZ disproved this critique partially because he was tested on his own biography which he had written, so he clearly knew all this information before the brain damage. Schmidtke & Vollmer (1997) tested over 100 amnesic patients on their ability to recall recent versus remote retrograde events/faces (similar to Albert study) and correlated it with their performance on standardized neuropsychological semantic and episodic memory tests. Recent retrograde memories correlated with performance on episodic memory (the better the performance on episodic memory, the better their ability to recall events close to the time of their brain damage), and old retrograde memories correlated with semantic memory (the better the performance on semantic memory, the better their ability to recall old events). Vargha-Khadem's young neurological patients had classic anterograde amnesia. They managed to acquire concrete and abstract knowledge about the world (intact semantic) despite not being able to recall any episodes within their own life (impaired episodic). Their deficits were spatial, temporal, and episodic. This study was used as evidence to the theory that you do not need episodic memory to acquire semantic knowledge. Semantic dementia patients have a breakdown in the central store of semantic memory (knowledge about the world) affecting both the verbal and nonverbal aspects of conceptual knowledge about objects, people, etc., but they have intact episodic memory, showing a double dissociation with amnesic patients.

Articulatory loop

Part of baddeley's model of working memory, aka phonological loop

Phonological similarity effect

Phonology is branch of linguistics concerned with the systematic organization of sounds in spoken languages and signs in sign languages. The phonological similarity effect is that verbal short-term memory stores in healthy individuals are greatly influenced by the phonological similarity of the information you want to retain. Short-term memory patients are also adversely affected, such that if you give them two or three items that would be in their span and manipulate the phonological similarity, there is about a 40% drop in performance when shown similar items as opposed to dissimilar items.

Procedural memory

Procedural memory, aka motor skills, is a type of implicit memory and long-term memory which aids the performance of particular types of tasks without conscious awareness of these previous experiences.

Source monitoring

Source monitoring errors occur when normal memory recall and perceptual processes are disrupted and a memory error occurs. Source monitoring itself is an unconscious mental test that humans perform in order to determine if a memory is "real" and accurate as opposed to being from an extraneous source like a dream or a movie. People use many sources to determine the source of a memory or idea. When a disruption in source monitoring occurs errors in recall can result as a source monitoring error. These occur when a specific recalled experience is falsely attributed to be the source of a particular memory. An example of a source monitoring error would be incorrectly recalling a conversation that occurred in a dream as reality.

Semantics

The branch of linguistics and logic concerned with meaning

Cohort model

The cohort model in psycholinguistics and neurolinguistics is a model of lexical retrieval first proposed by William Marslen-Wilson in the late 1970s. It attempts to describe how visual or auditory input is mapped onto a word in a hearer's lexicon

What is the House of Lichtheim (Ch. 11 p. 276)? How well does it characterize the major types of aphasia?

The diagram makers made a very simple model of transmission pathways and the symptoms associated with the different types of aphasia. The model isn't quite right, for example, Broca's aphasic patients can also have problems in comprehension, not just speech production. So, the deficit in "motor images" doesn't explain the main symptom of Broca's aphasic patients (agrammatism). Many patients who meet criteria for Broca's aphasia have damage in temporal lobes not Broca's area. Additionally, Wernicke's aphasic patients also have problems in speech production (e.g., neologisms). Wernicke's area involved in a variety of functions including linking acoustic information with visual and motoric information.

Define the four characteristic memory impairments in frontal lobe amnesia and how they may be assessed experimentally. How does the pattern of impaired/preserved memory compare to that of Korsakoff's patients and medial temporal lobe amnesic patients?

The four classical characteristics of frontal lobe amnesia are difficulty in retrieval strategies, difficulty in remembering the temporal order of events, problems with source memory, and difficulty with metamemory ("feeling-of-knowing"). Frontal lobe patients have difficulty utilizing appropriate retrieval strategies to recall events and memories, meaning when you ask a patient to recall information that they have learned, they have more difficulty than if they were given a straight recognition memory task ("which of these four words were on the word list we saw before?"). They need more extensive contextual support to retrieve a memory. Temporal ordering: if you show subjects a series of stimuli and afterwards show them pairs of stimuli and ask which of the pair was shown more recently in time, they will remember if they had seen the stimulus prior, but will have trouble remembering which one came before the other. Shimamura et al. (1990) looked at the temporal ordering deficit, giving subjects a list of 15 words and asking them to reproduce the same list order from a randomized list. They assessed the memory of their temporal order by correlating the judged order compared to the actual order of presentation. Frontal lobe patients exhibited a significant impairment in the temporal ordering test despite comparable performance to HC for word recall and word recognition. Milner et al. (1985) demonstrated this deficit by looking at frequency. She showed patients a series of designs and had them decide whether the design was composed of entirely straight lines, curved lines, or intermixed lines. Each individual design occurred a varying number of times (sometimes once, sometimes up to 9). The patients had to make a judgment about the physical aspect of the design, which means they were attending to it. In a later test, patients were asked how many times each individual design was presented. They plotted the actual frequency of each design versus the estimation of the patient of the frequency. The patient groups were left and right temporal lobe patients, left and right frontal lobe patients. Frontal lobe patients show a blunted sensitivity to this frequency. For source memory, patients will learn a fact but not recall where they have learned it. Failure of temporal ordering is related to source memory, or the disconnection between knowing the factual information and recalling the context in which the information was learned. If you cannot recall the context, you will also not be able to recall when you encountered the information. Janowsky et al. (1989) tested source memory by telling frontal lobe patients 20 trivia facts they didn't already know, for example "the name of the dog on the cracker jacks box is Bingo." They later did a cued recall test for these 20 trivia facts and 20 old trivia facts. They assessed the ability to recall the trivia fact the patient had been told in the last session. If they got it correct the experiments would ask where they had learned this information. In response to this question, the patients would make two kinds of source errors: either saying that they had learned the trivia fact elsewhere when they had in fact learned it from the experimenters, or they would say the opposite and say they had learned it from the experimenters when they had learned it elsewhere. Frontal lobe patients show a large amount of source errors relative to young and older controls (to be discussed more). Even though source errors are higher, the amount of information they recalled is comparable to controls. Metamemory or "source-of-learning" is knowledge about one's capacity to encode things effectively, to be able to use mnemonic devices to help organize and retrieve when demands on memory are large. Having awareness of where you struggle with memory can allow you to engage in strategic organizational and encoding processes to allow you to better support your memory. Metamemory was assessed by Janowsky et al. (1989) who gave patients a series of study words/sentences ("Patty's garden is full of marigolds") and afterwards would give them a cued recall test ("Patty's garden is full of what?"). They then tested the recall with a multiple choice test to see if they could recognize the answer even if they could not recall it. They tested feeling of knowing by having them rate on 4 point scale the likelihood of them knowing the answer. Finally, they were given a recognition test where they had to identify which of four items was the correct final word. Subjects were given 20 sentences to learn. Frontal lobe patients, korsakoff patients, and amnesic patients were tested. They compared patients of korsakoff patients and amnesic patients after a five minute delay and frontal lobe patients after a 1-3 day delay. They correlated ability to identify the correct of the four choices to their rating on the feeling of knowing task. The graph shows that frontal lobe patients' had a comparable level of feeling of knowing HC after a 5 minutes day but not after a 1-3 day delay. At this point, their feeling of knowing did not correlate well with recognition. So, metamemory is not good after a few day delay. Medial temporal amnesic patients do better on their feeling of knowing in terms of correlating rating with actual patients, but korsakoff patients have no metamemory after five minutes.

Recollection

The operation by which objects are recalled to the memory, a slower process that retrieves item-specific episodic information

Lexical access

The process by which the basic sound-meaning connections of language, i.e., lexical entries, are activated.

Describe the auditory pathway that sound travels from the ear to the brain. How does the organization and feature processing characteristics of the auditory system compare to that of the visual system?

The outer ear/external auditory canal amplifies certain frequencies and is important for sound localization (one way is related to the amount of information received in each ear/when sound waves hit one and then the other, the other is related to the characteristic of the ear canal and the information acquired over time and knowing where things are based off when they hit your particular ear). There is active transmission into an auditory signal, into the auditory nerve and beyond. The outer ear is a pinna that reflects sounds wave within its folds. The middle ear converts airborne vibrations to liquid-borne variations with relatively minimal loss of energy. The tympanic membrane, or the eardrum, has a pathway through the three bones, the malleus, incus, and stapes (this hits the oval window). The tiny bones transfer the mechanical pressure on the eardrum at the end of the canal to a smaller membrane, the oval window which contains the entrance to the fluid filled cochlea. The inner ear converts liquid-borne sounds to neural impulses. If you were to unwind the cochlea, inside is the basilar membrane. The membrane contains tiny hair cells that are linked to receptors. The hair cells are differentially sensitive to different frequencies of sound (the place theory idea of how we represent different frequencies). The hair cells closest to the oval window are most sensitive to highest frequency sounds and hair cells closer to the inner part are more sensitive to the lower frequency sounds. You have to wait until have information from both channels to get coding information for where the sound is localized. This schematic goes from midbrain structures up to the medial geniculate body up to area A1, which is the analogous primary auditory center just like in visual with V1 (equivalent function of A1). There are 4-5 synapses going from ear to cortex. The auditory nerve passes through the medial geniculate nucleus on the way to the primary auditory cortex ("core") in the temporal lobes. There are other pathways that support other characteristics of auditory processing, such as pathway that goes to the lateral lemniscus of the midbrain, which is important for timing information. Once you get from the midbrain to the thalamus to area A1, there is the "core" surrounded by the parabel, which has more complex information about the auditory stimulus. Area A1 is located in Heschl's gyrus in the temporal lobe and is surrounded by the adjacent auditory belt and parabelt regions. There is some information that projects that come directly from the medial geniculate nucleus to area A1 and the other parabelt regions. There are a lot of similarities between the organization of the audio and visual systems. There are also descending top-down projections that go all the way down to the cochlear nuclei on processing. There are information errors projected to the opposite cortex but it is not complete as it is with vision. Just as with retinotopic organization in visual processing, there is a tonotopic organization in audio processing. The neurons that are sensitive to different frequencies are adjacent to each other and system (image to right).

Compare the characteristics of the short-term and long-term memory stores.

The short-term and long-term stores differ in terms of duration, capacity, and code. The duration of the short-term store is about 30 seconds without rehearsal. The capacity of the short-term store is about 7+/-2 items. However, this number can be increased with use of "chunking" or mnemonic devices. Items in short-term store are coded acoustically. There is a phonological distinction effect for short-term memory where phonologically similar information is recalled more easily. The duration of the long-term store is indefinite, effectively infinite. The capacity is infinite as well. Items in long-term store are coded semantically. There is no phonological distinction effect, but information that is semantically related is recalled more easily.

List learning task

The ten-word learning task is a test of long-term memory stores which gives the patient a list of ten words and asks the patients to repeat it. The task counts how many trials it takes for the patient to learn the list. For healthy controls, this task took nine trials, which is about the same amount of trials as patients short-term memory syndromes (but Patient PV only took four trials).

Characterize Alcoholic Korsakoff's syndrome. Define the two stages and how they differ. How does a Korsakoff amnesic patient differ from a medial temporal lobe amnesic patient? (Hint: connect to the frontal-lobe amnesia lecture.)

The two main types of amnesic patients are alcoholic korsakoff's syndrome patients and medial temporal lobe amnesia patients (Patient HM). The Wernicke-Korsakoff syndrome was first described in the 1880s. Wernicke described one phase of this disorder and Korsakoff described the other without realizing they were studying the same patients. Wernicke described a patient with ataxia, abnormal eye movements, and a general state of psychological confusion, which he attributed to an inflammatory disease of the subcortical brain structures. He noted that the symptoms were progressive and led to death within five weeks. Six years following the publication, Korsakoff published a series of report describing the amnesic symptoms accompanying the symptoms described by Wernicke—amnesia, personality changes, tendency to confabulate (making up stories that may or not be true, who knows). If the condition is not treated with large doses of thiamine, the patient has fatal, midbrain hemorrhages. If the patient has the proper vitamin therapy, they can live, which is why this syndrome is not prevalent today because our food is fortified with vitamins. The Wernicke phase is the transient, confused state, but this will clear in 2-4 weeks with treatment, then reaching the Korsakoff phase. The patient can then maintain coherent conversations and pass psychological exams, but they have chronic, severe amnesia. During the stages of alcohol dependency, patients were often described as antisocial, aggressive, and engaging in petty crimes. In the onset of the Korsakoff phase, there was a dramatic change—all the impulsivity and aggression in the state of alcohol use is replaced by apathy and a disinterest in life, including no interest in drinking. They are unable to initiate to formulate or carry out a series of plans, which is reminiscent of frontal lobe patients—no goal-directed behavior. When asked to recall their activities of the previous day, the patients would fill in the gaps in their memory with a story of when they went to a sporting event years prior, for example (confabulation). Brain damage as well as neurochemical dysfunctions in alcoholic korsakoff's syndrome are probably due to combinations of thiamine deficiency (malnutrition, vitamin B1 deficiency) and neurotoxic effects of the alcohol. The brain damage in these patients comprises the medial diencephalic structures, the mammillary bodies, mediodorsal nuclei, and thalamic nuclei. These are midline structures have connections to the medial temporal lobe structures, which connections are disrupted, leading to memory deficits. Medial temporal lobe amnesic patients have damage primarily to the medial temporal lobe structures. There are variable amounts of damage across different patients, leading to interesting dissociations between patients. Medial temporal lobe patients reflect deficits in the declarative store and conscious memory, whereas alcoholic korsakoff's syndrome patients have that plus frontal lobe impairments. There are characteristics of alcoholic korsakoff's syndrome patients that reflect some of the damage associated with frontal lobe patients. Patients with medial temporal lobe damage does not participate in the spontaneous confabulation that you see in alcoholic korsakoff patients.

Describe the neuropsychological evidence for the idea that the hippocampus is particularly important in the formation of episodic memories. What do Vargha-Khadem's patients tell us about the organization of declarative memory? Semantic dementia patients?

Vargha-Khadem's patients Jon, Beth, and Kate all had bilateral hippocampal damage with their other brain structures normal. All three showed classic anterograde amnesia, but normal or near-normal intelligence, had made normal progress through school, and managed to acquire concrete and abstract knowledge about the world despite not being able to recall any episodes within their own life. So, they managed to acquire concrete and abstract knowledge about the world despite not being able to recall any episodes within their own life. They have no integrated spatiotemporal emotional context for everything they experiences in the world, so everything they recalls about their life is schematized. This suggests that hippocampus plays an essential role in orchestrating the storage and retrieval of all of the emotional aspects of an experience. They were assessed experimentally in three ways: a story recall test, a word list recall, and visual memory recall. In each of the tasks, the patients forgot after the delay in the second condition. This study was used as evidence to the theory that you do not need episodic memory to acquire semantic knowledge. Verfaellie et al. (2000) conducted a study which looked at two patients, SS and PS. SS and PS differed in the region of brain damage (damage for SS was in the hippocampus plus surrounding cortical areas, PS was hippocampus only), but both had severe amnesia. SS was a 71 year old man who developed amnesia in 1971 secondary to herpes simplex encephalitis. He was a former scientist with 18 years of education and high performance on the IQ test, but he had no knowledge of words that had entered into the world lexicon since his amnesia (like "Uber"). PS was a 40 year old who developed amnesia in 1981 subsequent to anoxia subsequent from an asthma attack. His premorbid semantic knowledge was variable, but he maintained the ability to acquire some semantic knowledge. To assess the semantic representation of anterograde memory, researchers asked both patients were asked to define a new word that had come into existence since brain damage. SS's performance on this task (assessed by a four-choice recognition test) testing what the words meant was at chance level. PS did fairly well on the test, which suggested that she acquired some semantic knowledge post brain-damage despite severe episodic memory impairments. In a similar task, the patients were shown black and white images of people who became famous after their brain damage, which produced similar respective results for SS and PS. This study suggests that the hippocampus may not be needed necessarily for acquisition of semantic knowledge, but more extensive damage to the surrounding areas does affect acquisition of new semantic knowledge. In terms of how dissociable the episodic and semantic memory types are, these studies suggest that there could be some dissociation. Semantic dementia causes breakdown in the central store of semantic memory (knowledge about the world) affecting both the verbal and nonverbal aspects of conceptual knowledge about objects, people, places, facts, etc.

Melody

a sequence of single notes that is musically satisfying. Within music, you can have tone deafness and still understand melody, so there are dissociable mechanisms within music

Syllable

a unit of pronunciation having one vowel sound, with or without surrounding consonants, forming the whole or a part of a word

False memory

an apparent recollection of an event that did not actually occur

Phonological/literal paraphasia

non-words clearly related to real word (say "pez" instead of peas)

Timbre

perceived sound quality of a musical note, sound or tone. ... In simple terms, timbre is what makes a particular musical sound have a different sound from another, even when they have the same pitch and loudness

Head-related transfer function

response that characterizes how an ear receives a sound from a point in space. As sound strikes the listener, the size and shape of the head, ears, ear canal, density of the head, size and shape of nasal and oral cavities, all transform the sound and affect how it is perceived, boosting some frequencies and attenuating others

Pure tones

tone with a sinusoidal waveform; this is, a sine wave of any frequency, phase, and amplitude

Freudian slip

A Freudian slip, also called parapraxis, is an error in speech, memory, or physical action that occurs due to the interference of an unconscious subdued wish or internal train of thought. The concept is part of classical psychoanalysis.

Malapropisms

A malapropism is the use of an incorrect word in place of a word with a similar sound, resulting in a nonsensical, sometimes humorous utterance.

Morpheme

A morpheme is the smallest meaningful unit in a language. A morpheme is not identical to a word, and the principal difference between the two is that a morpheme may or may not stand alone, whereas a word, by definition, is freestanding

Describe the memory characteristics of a short-term memory syndrome patient. Based on the studies described in class, what components of memory are intact and what are impaired in this syndrome? What do the results of these studies tell us about the organization of our memory systems?

A short-term memory syndrome patient performs normally on tasks that assess long-term memory, problem-solving behavior, speech perception, and speech production. The only tasks they are impaired on are tests that assess solely short-term stores, such as the WAIS digit span task. Since STM syndrome patients encode successfully to long-term memory and rely on long-term memory to compensate for deficiencies in their short-term store (STS), this shows that our memory system is not serial as shown in the Atkinson & Shiffrin modal model, rather the long-term and short-term stores are in parallel.

I described two studies in class looking at the pattern of retrograde memory impairment in amnesic patients. The patterns of results are opposite in the two studies. Why? What are the crucial experimental design differences between the studies that likely led to these apparent contradictory findings?

Albert et al. (1979) looked at the ability of amnesic syndrome patients to identify faces of famous people. They had 24 black and white photos of people who became famous in different decades. They asked the patient if they knew who the person was. If the patient said no, they would give a phonemic cue (it begins with this sound "ma"), and if that did not work they would give a semantic cue (i.e. for Elvis, they would say he was a singer). For a second task, the researcher would give patients information about a public event or a famous person and the patient would have to describe the event. They graphed the mean % correct as a function of decades (right). The Korsakoff patients show a classic temporal gradient, but healthy controls show no temporal gradient. In the study, the researchers picked faces where memorability of stimuli was controlled to be about 80% accurate for HC. One criticism/possible fallout of study is that Korsakoff patients were severe alcoholics prior to brain damage, so it is possible that temporal gradient is due to patients not encoding the information because they were not paying attention to the world in the period of their alcoholism. The Albert et al. (1979) study showed a temporal gradient, but there was an earlier study that did not show the temporal gradient for retrograde memories, conducted by Sanders and Warring (1971). The Sanders & Warrington study, in fact, shows an uptick in recall for contemporary times as compared to more remote times. Why do these studies show what appears to be an opposite pattern of results? The studies were designed in different ways. Both tested recall for events and famous people that had come into fame at different time periods (plotted on x-axis). Albert designed the study for controls to remember each decade at 80% accuracy (data picked based on the memorability for control group, so HC do not show temporal gradient and Korsakoff patients do), but Sanders and Warrington did not. Instead, Sanders and Warrington picked the "top 100 events" listed for a given year, so they were the events considered notable in that same year. Of this list, they picked the events ranked between #10-20 most memorable (so not the most memorable) and tested how well the patients could recall them. The critical difference in these studies is that Albert chose their memories that they wanted to assess based on how well you could retrieve those memories of faces and events at the time of test, compared to Sanders and Warrington who chose memories and faces and events during the different time periods based on the memorability at the time at which they were encoded. In the study, Sanders & Warrington did a free recall test and then a multiple choice follow-up. Both subjects show slightly better performance under multiple choice conditions. There is better recognition for contemporary times than when you go further back, and amnesic patients show the same pattern (no gradient, if anything, a slight uptick in memories closest to the brain injury). Doing two different methods of matching (free recall, multiple choice) elicit qualitatively different effects although they are quantitatively matched. When we first encounter memories and faces, they have a certain amount of episodic stores engaged and a certain amount of semantic stores engaged. Initially, you may have a large percentage of that memory driven by the episodic store and a small percentage driven by the semantic store. One hypothesis is that over time, those older memories become more stable in part because they become more driven by semantic memory stores. How would this happen? Repeated exposure, repeated rehearsal—the process of overlearning increases the support in representation in semantic memory. For some memories that initially are largely driven by episodic stores, they may become more semanticized over time. If you do not rehearse the memory very much its representation in episodic stores will go down, and there will not be much representation in semantic memory because you have not rehearsed or overlearned it. With rehearsal, semantic representation will grow over time. If you match on the basis of how memorable the event was at the time when you encoded that event (like the Sanders study) you match the relative contribution of episodic and semantic memory stores across decades. Since semantic memory is more stable over time, episodic memory will more deteriorate over time than semantic (fitting the results from the Sanders study). Even though memorability is constant, ability to recall things in episodic memory degrades. If events were chosen based on memorability at time of occurence, you will not see a gradient, particularly if events chosen were not rehearsed very much after they were initially laid down.

Korsakoff's syndrome

Alcoholic korsakoff's syndrome results from long-term alcohol addiction or overuse. Brain damage as well as neurochemical dysfunctions are probably due to combinations of thiamine deficiency (malnutrition, vitamin B1 deficiency) and neurotoxic effects of the alcohol. The brain damage in these patients comprises the medial diencephalic structures, the mammillary bodies, mediodorsal nuclei, and thalamic nuclei. These are midline structures have connections to the medial temporal lobe structures, which connections are disrupted, leading to memory deficits. There are characteristics of alcoholic korsakoff's syndrome patients that reflect some of the damage associated with frontal lobe patients. Medial temporal lobe patients reflect deficits in the declarative store and conscious memory, whereas alcoholic korsakoff's syndrome patients have that plus frontal lobe impairments.

Constructive memory

An apparent memory of an event that did not actually happen, unconsciously constructed to fill a gap. when we remember, we piece together fragments of stored information under the influence of our current knowledge, attitudes, and beliefs

Semantic reversibility

An example of a semantically reversible sentences is "The two men, George and Carl, were closely watched." These sentences have an interesting property in that when the subject and the object are swapped or reversed (e.g., "The two men, George and Carl, watched them closely"). The exact meaning of the sentence changes. Patients with short-term memory syndrome, Patient IL specifically, reverse the semantic meaning of their sentences when the number of words exceeds the capacity of their short-term store. This suggests the phonological loop does something fundamental in terms of auditory speech comprehension.

What is aphasia? Describe the different components of clinical testing of aphasia? How are the major types of aphasic syndromes characterized by these clinical tests?

Aphasia is "the disturbance of any or all of the skills, associations and habits of spoken or written language produced by injury to certain brain areas that are specialized for these functions" (Goodglass & Kaplan, 2001). There can be many different types of aphasic patients. Aphasia is not disturbances in communication due to paralysis, lack of coordination or damage of muscles used for speech or writing, or impaired vision or hearing. Aphasia can affect auditory comprehension, oral expression (Wernicke's and Broca's patients), word finding (can't come up with word you want to produce), reading (will not discuss), and writing (will not discuss). Clinical testing for aphasia includes tests of conversational speech (fluent vs. nonfluent, paraphasia), comprehension of spoken language (not all or none phenomenon), repetition, and anomia/word finding. Repetition is the ability to repeat words presented by examiner. In aphasia, the ability to repeat lends information about where the disruption is in the auditory language processing network. Word finding/anomia is when patients are unable to recall a particular word. Almost every aphasic patient has difficulties with word finding but the level of impairment varies. If you ask them to name real pictures of objects, you will see the problem is most evidence in the case of nouns. There are two categories of speech: omission or commission. In terms of non-fluent speech in Broca's aphasia, there is often agrammatism (inadequate sentence production, attempts to make a sentence but the skeleton of the sentence is missing). For example, a patient said "cookie jar...fall over...chair...water...empty" to describe the cookie jar image, so they understand content but cannot make a coherent picture. In terms of fluent speech in Wernicke's aphasia, their jargon is lengthy with fluently articulated utterances which make little or no sense to listener. For the cookie picture: "Uh, well this is the...the /dodu/ of this. These things going in there like that. This is /sen/ things here. This one here, these two things here..."

Articulatory suppression

Articulatory suppression is the process of inhibiting memory performance by speaking while being presented with an item to remember. This is practiced in the Brown-Peterson Paradigm. In the classic experiment, the patient is given a consonant trigram (e.g., DBX) and then is read a 3-digit number (e.g., 781). The patient then has to count backward from that number by 3's. The experimenter varies the amount of time that the patient has to count before asking them to recall the 3 consonants in order. The curve on the right shows the proportion correct of the consonants with the variable of distractor duration in seconds. The proportion correct decreases reliably as the distractor duration increases. also practiced in: One suggestion is that short-term memory functions as working memory. Up to this point, we have been using short-term memory, working memory, immediate memory as interchangeable words—but are they all the same? Is the short-term store working to hold and manipulate material being held in your consciousness? Is it involved in tasks such as mental arithmetic, reasoning, and problem solving? If they are all the same and the same module is playing a role in both, then there should be a lot of interference in performing the two tasks simultaneously. Baddeley & Hitch (1974) tried to test this hypothesis by having subjects solve logic problems (True/False questions about BA, to the right) while simultaneously having them repeat a sequence of numbers held in working memory, such as 73192. Baddeley & Hitch timed how quickly they could solve the true/false problems and varied the number of digits the subject had to repeat (the dependent measure was the number correctly answered in 3 minutes). They found that the number of correctly answered problems did not change whether or not the vocalization task was occurring simultaneously. When the span of numbers reached six digits, there was evidence of slowing in reasoning ability. In general, there is not the evidence of profound interference that you would expect if these two tasks used the same module.

Amnesic syndrome patients typically demonstrate a temporally-graded retrograde amnesia for events in their lives prior to brain damage. Describe this temporal gradient. What are the 5 different explanations given for this temporal gradient? How does the gradient differ from that of semantic dementia patients? What does it suggest about the structure/nature of recent vs. remote memories?

Can arise because the stimuli are not carefully matched across decades Stimuli for more remote decades are easier (Sanders & Warrington, 1971) Apparent loss of retrograde knowledge is anterograde amnesia in Disguise. Alcoholics who subsequently go on to develop Korsakoff's amnesia may not have fully encoded the memories in the first instance. Does not account for all cases (e.g., Butters & Cermak), but may account for some. Older memories become more semantic-like and less episodic with the passing of time because they get rehearsed more often. Childhood memories become more like stories than memories (Cermak & O'Connor, 1983). Each time an old event is remembered, a new memory for that event is Created. The older the event, the greater the number of traces & the more resilient to brain damage it will be (Nadel & Moscovitch, 1997). The hippocampus has a time-limited role and the more consolidated a memory is, the less dependent on the hippocampus it is (Squire, 1992). There is a temporal gradient for episodic memory deficiencies in that amnesic patients have more difficulty recalling memories closest to the time of brain injury. Patient HM, a medial temporal lobe amnesic patient, lost memory of the three years prior to the surgery, but his memory improved for older memories. Ribot's law is that amnesic patients have generally better memory for early life than later life events. (multiple trace theory) The temporal gradient happens because memories early on in life, particularly those you can recall, are memories that you have recalled and talked about multiple times. Every time you recall or reactive that memory, another trace of that memory gets laid down. This is why distinctive events, for example a trip or a prom, is more memorable than a day in a class that was like every other in most ways. Whenever an event is retrieved, you get a new trace laid down in your memory system. Older events are protected from brain damage because of the multiple traces of the memory that have been laid down from that event. For Korsakoff patients, it was propose that the temporal gradient was due to patients not encoding the information because they were not paying attention to the world in the period of their alcoholism. However, this was disproved to an extent by patient PZ with his biography. Another explanation: Since semantic memory is more stable over time, episodic memory will more deteriorate over time than semantic (fitting the results from the Sanders study). Even though memorability is constant, ability to recall things in episodic memory degrades Episodic memories may be special by virtue of the fact that they contain rich contextual detail, which may be linked together by structures in the medial temporal lobe and may be gradually consolidated over time. In contrast, semantic memory may be initially context dependent, but becomes less so over time, which is why semantic memories are relatively robust to hippocampal damage in our amnesic syndrome patients. Semantic dementia patients show the reverse temporal gradient of amnesic patients. Schmidtke & Vollmer (1997) tested over 100 amnesic patients on their ability to recall recent versus remote retrograde events/faces (similar to Albert study) and correlated it with their performance on standardized neuropsychological semantic and episodic memory tests. Recent retrograde memories correlated with performance on episodic memory (the better the performance on episodic memory, the better their ability to recall events close to the time of their brain damage), and old retrograde memories correlated with semantic memory (the better the performance on semantic memory, the better their ability to recall old events).

Categorical perception

Categorical perception is a phenomenon of perception of distinct categories when there is a gradual change in a variable along a continuum. It was originally observed for auditory stimuli but now found to be applicable to other perceptual modalities. There are two theories with how we deal with variability. First, categorical perception which suggests that continuous changes in input are mapped onto discrete percepts. These may be mapped onto abstract representations that specify nature of acoustic signal in terms of voicing, phonemes, syllables.

Coarticulation

Coarticulation is that consecutive speech sounds blend into each other due to mechanical constraints on articulators. the articulation of two or more speech sounds together, so that one influences the other

Consolidation vs. Multiple Trace theory

Consolidation is a process with moment-to-moment change in brain activity that is translated into permanent structural change in the brain. In the multiple trace theory alternative hypothesis, the hippocampus is involved in permanent aspects of memory storage. Unlike the consolidation view where the hippocampus has a time-limited role, there is a role in supporting memory that is not time limited. In the initial model of the multiple trace theory, the temporal gradient is explained by the multiple memory traces of events being created—whenever an event is retrieved, you get a new trace laid down in your memory system. Older events are protected from brain damage because of the multiple traces of the memory that have been laid down from that event. The newer version of this multiple trace theory distinguishes between contextualized versus schematic memories. In summary, the consolidation theory sets a time-limited role for the hippocampus. The multiple trace theory actually posits a transformation in the memory itself, going from a more contextualized to schematic base. There is transfer to cortical areas in terms of supporting these schematic memories, but the memory has also undergone a fundamental change from when you laid down that memory.

Describe Craik and Watson's study with healthy subjects. What did their results tell us about the role of rehearsal time in the relative encoding strength of memories?

Craik & Watkins tested undergrads in a psychology course. The participant was given a list of words with a target letter to pay special attention to. At the end of the list, the student has to say which was the last word that began, for example with the letter g, for example. Each new list (there were 21) had a different rule or instruction. The experimenters manipulated how fast they presented the words and varied how many words were between each critical word to test the effect of different amounts of rehearsal time on memory. Immediately following the last list, they were given a distracting exercise such as 1 minutes of arithmetic, after which there was a surprise recall test where the participants were given 10 minutes to write down every word that they could recall from the lists. They looked at the probability of recalling the critical words as a function of how much rehearsal time there was. They plotted how many critical words were reported as a function of rehearsal time. The graph does not show a trend, except that there was a slight bump for recalling the last critical word. The conclusion of their study was that rehearsal time does not matter and speed of presentation does not matter to the encoding of information into long-term memory (more elaborate processing is what will affect the encoding of information into long-term memory to then later retrieve it).

Semantic vs. episodic memory

Endel Tulving was the first to introduce the distinction between episodic memory: recall of events in our life that have a particular spatial-temporal context as opposed to semantic memory: memories for world knowledge that may or may not relate to events in your life (for example, you do not have a spatiotemporal context for when you learned 2+2=4). Tulving suggested that episodic memory involves conscious awareness of past events/personal autobiographical knowledge, sometimes called mental time travel. Semantic knowledge is world knowledge that we remember in the absence of memory of specific circumstances surrounding its learning. One question that has been posed is how dissociable are these memory types?

How is "hearing" a constructive, rather than simply a perceptual process? What are some of the different types of information acoustical signals can convey to the listener? What are some of the issues that the brain must contend with to extract the signal from our noisy auditory environment?

For constructing a physical model of the auditory world, we must ask what objects do the sounds correspond to? Where do sounds emanate from? What is the significance of the sound? Auditory sounds are bombarded with lots of sound, so some sounds are filtered out—we must choose where to dedicate attentional resources.

Describe the Brown-Peterson paradigm. What does it tell us about the duration of items held in short-term memory store?

In the Brown-Peterson Paradigm, the patient is given a consonant trigram (e.g., DBX) and then is read a 3-digit number (e.g., 781). The patient then has to count backward from that number by 3's. The experimenter varies the amount of time that the patient has to count before asking them to recall the 3 consonants in order. The proportion correct decreases reliably as the distractor duration increases. The Brown-Peterson Paradigm allows us to know that a person only has 15-30 seconds without rehearsal to retain information in your short-term store.

Digit span task

In the WAIS digit span task, patients are tested on how many numbers they can repeat in a string immediately after hearing it. Retention span for healthy individuals is usually 7 +/- 2 numbers, not taking into account mnemonics or "chunking," which is breaking the list of numbers into subgroups, such as by pausing momentarily between digits while reading the list. STM syndrome patients are significantly impaired on the digit span task.

Wernicke's aphasia

In this form of aphasia the ability to grasp the meaning of spoken words and sentences is impaired, while the ease of producing connected speech is not very affected. Therefore Wernicke's aphasia is also referred to as 'fluent aphasia' or 'receptive aphasia'. Reading and writing are often severely impaired. As in other forms of aphasia, individuals can have completely preserved intellectual and cognitive capabilities unrelated to speech and language. Persons with Wernicke's aphasia can produce many words and they often speak using grammatically correct sentences with normal rate and prosody. However, often what they say doesn't make a lot of sense or they pepper their sentences with non-existent or irrelevant words. They may fail to realize that they are using the wrong words or using a non-existent word and often they are not fully aware that what they say doesn't make sense. Patients with this type of aphasia usually have profound language comprehension deficits, even for single words or simple sentences. This is because in Wernicke's aphasia individuals have damage in brain areas that are important for processing the meaning of words and spoken language. Such damage includes left posterior temporal regions of the brain, which are part of what is known as Wernicke's area, hence the name of the aphasia

Levels of processing vs. encoding specificity

Levels of processing: The idea that the way information is encoded affects how well it is remembered. The deeper the level of processing, the easier the information is to recall, encoding specificity, encoding specificity: human memories are more easily retrieved if external conditions (emotional cues) at the time of retrieval are similar to those in existence at the time the memory was stored

What is metamemory and what might be its function in memory?

Metamemory or "source-of-learning" is knowledge about one's capacity to encode things effectively, to be able to use mnemonic devices to help organize and retrieve when demands on memory are large. Having awareness of where you struggle with memory can allow you to engage in strategic organizational and encoding processes to allow you to better support your memory. Metamemory was assessed by Janowsky et al. (1989) who gave patients a series of study words/sentences ("Patty's garden is full of marigolds") and afterwards would give them a cued recall test ("Patty's garden is full of what?"). They then tested the recall with a multiple choice test to see if they could recognize the answer even if they could not recall it. They tested feeling of knowing by having them rate on 4 point scale the likelihood of them knowing the answer. Finally, they were given a recognition test where they had to identify which of four items was the correct final word. Subjects were given 20 sentences to learn. Frontal lobe patients, korsakoff patients, and amnesic patients were tested. They compared patients of korsakoff patients and amnesic patients after a five minute delay and frontal lobe patients after a 1-3 day delay. They correlated ability to identify the correct of the four choices to their rating on the feeling of knowing task. The graph shows that frontal lobe patients' had a comparable level of feeling of knowing HC after a 5 minutes day but not after a 1-3 day delay. At this point, their feeling of knowing did not correlate well with recognition. So, metamemory is not good after a few day delay. Medial temporal amnesic patients do better on their feeling of knowing in terms of correlating rating with actual patients, but korsakoff patients have no metamemory after five minutes.

Describe the organization and functional characteristics of the component modules within the informational processing model of music perception described in the textbook (p. 244). What is some of the neuropsychological evidence to support the structure of this model?

Music is considered special in the realm of auditory perception. Music, like vision, may be decomposed into different component mechanisms (to the right). The blue boxes in the Peretz & Coltheart (2003) model are not specific to music per se, but the green boxes are important for music processing. Evidence for model comes from studies of Patient CN, Patient KE, patients with congenital amusia, and Patient SM. Patient CN had bilateral temporal lobe damage and lost memory for musical tunes. Heitsch et al. looked at Alzheimer's patients and semantic dementia patients and found impaired memory for tunes that was linked to semantic memory impairments, which suggests that musical knowledge has priority in right anterior temporal lobe. When semantic dementia patients have damage to the left temporal lobe (where knowledge about the world is stored), there is loss of semantic knowledge, but loss of musical lexicon seems to be right lobe located. Music has been used as rehabilitative measure for Alzheimer's patients to support memory retrieval under some conditions. Patient KE had difficulty in rhythm perception/production, but was fine on pitch. Congenital amusia/tone deafness affects about 4% of the population (unclear what the impairment is, but they can still do rhythm analyses and identify melodies). Patient SM had amygdala damage, and emotional content of music can be affected with damage to limbic structures—patient had impaired recognition of "scary" music (Gosselin et al., 2007) (relationship of music to emotional processing). The patients show dissociations of one component mechanisms versus the other.

What is the defining characteristic that distinguishes a patient with word-meaning deafness from a patient with pure word deafness? What are the two necessary conditions for a patient to be categorized as having word-meaning deafness?

One of the first cases of word meaning deafness was described by Bramwell (1887). The patient was a 26 year old woman who had a stroke 11 days after giving birth. After a few weeks of recovery, she started speaking spontaneously, asking questions, and seemed to be saying what she intended upon speaking despite sometimes using the wrong words. So, her speech production, reading, and writing were intact. Her impairment was in speech comprehension. She had otherwise normal hearing on audiometric tests. What distinguished a word meaning deaf patient from a pure word deaf patient is that word meaning deaf patients have intact repetition: the patient could repeat back words and sentences without understanding what the words and sentences meant. She could transcribe what was said but would not understand until she had written down what was said. Kohn & Friedman (1986) described two conditions for word meaning deafness: the word must have undergone adequate acoustic analysis as evidenced by correct repetition (to distinguish from pure word deafness), and the semantic representation of the word must be intact as evidenced by immediate comprehension of the word when presented in written form (to rule out that there is not a semantic memory or conceptual knowledge deficit).

What is the neuropsychological evidence for distinguishing between anomia arising at the semantic level and anomia arising at the level of the speech output lexicon? Why do impairments at these different levels produce these particular characteristics? How do occasional anomic errors in healthy adults relate to this cognitive framework?

Patients with anomia at semantic level impairment will make semantic errors in naming and will be poor at detecting those errors as incorrect. Patients with anomia at speech output lexicon will not show semantic naming errors. The probability of being able to produce a word correctly will be strongly affected by its frequency of use. Patients will make phonological approximation errors to some words they cannot fully express. Word finding/anomia is when patients are unable to recall a particular word. Almost every aphasic patient has difficulties with word finding but the level of impairment varies. If you ask them to name real pictures of objects, you will see the problem is most evidence in the case of nouns. Paraphasias are the production of unintended syllables, words, or phrases during the effort to speak. This reflects a breakdown at the stage of word retrieval process and is a dominant symptom in anomia.

Long-term potentiation

Persistent strengthening of synapses based on recent patterns of activity. These are patterns of synaptic activity that produce a long-lasting increase in signal transmission between two neurons.

Describe the differences in speech processing errors shown in word-meaning deaf patients classified as either pre-access or post-access type. In terms of our cognitive model, where is the damage localized for these types of word-meaning deafness?

Prototypical post-access patient (writing is intact for regular and irregular words): Patient HN was a 53-year-old man suddenly became unable to speak. He was initially described as having Wernicke's aphasia. He had severe comprehension difficulties, he had fluent paraphasic speech with semantic and phonemic paraphasias as well as neologism. He was tested two months post symptom onset, at which point his speech was fluent and only mildly paraphasic (semantic and phonemic), good naming ability, and mildly impaired at repetition. Prototypical pre-access patient (impairment for the ability to write to dictation for irregular words): Patient LL suddenly had trouble speaking, 64 year old right handed man. There were frequent phonemic and semantic paraphasias and occasional neologisms. He could not repeat short words or answer questions auditorily but could be answered in written forms. When he was evaluated three months post onset, his performance had improved so that he could do the test. The difference in terms of pathology was that in a CT scan, HN had a lesion in Wernicke's area that extended superiorly into the angular gyrus (the surface) whereas LL had both surface and deep lesions (more extensive damage). Pre-access breaks the pathway between the auditory analysis system and the auditory input lexicon, and post-access breaks the pathway between the auditory input lexicon and the semantic system.

How do we explain forgetting things at the levels of encoding, storage, and retrieval (see textbook)?

Psychologists distinguish between three necessary stages in the learning and memory process: encoding, storage, and retrieval (Melton, 1963). Encoding is defined as the initial learning of information; storage refers to maintaining information over time; retrieval is the ability to access information when you need it. All three stages are interdependent. An important first principle of encoding is that it is selective: we attend to some events in our environment and we ignore others because of limited memory resources. Distinctiveness is a key to encoding events (you will likely not encode a typical day in math class as opposed to a senior prom). Storage: Rather, when we remember past events, we reconstruct them with the aid of our memory traces—but also with our current belief of what happened. In a phrase, remembering is reconstructive (we reconstruct our past with the aid of memory traces) not reproductive (a perfect reproduction or recreation of the past). Retroactive interference refers to new activities (i.e., the subsequent lunches) during the retention interval (i.e., the time between the lunch 17 days ago and now) that interfere with retrieving the specific, older memory (i.e., the lunch details from 17 days ago). But just as newer things can interfere with remembering older things, so can the opposite happen. Proactive interference is when past memories interfere with the encoding of new ones. The type of hints, or cues, in the environment can be critical to retrieval. The encoding specificity principle states that, to the extent a retrieval cue (the song) matches or overlaps the memory trace of an experience (the party, the conversation), it will be effective in evoking the memory. Every time we retrieve a memory, it is altered. For example, the act of retrieval itself (of a fact, concept, or event) makes the retrieved memory much more likely to be retrieved again.

Pure word deafness

Pure word deafness patients have damage to auditory analysis system, so they have difficulty in parsing sound waves into component phonemes. Pure word deafness causes impaired speech comprehension and poor repetition. Patients complain that words have no meaning. They can hear but not understand, meaning they have normal hearing on audiometric testing and normal performance on perceiving pure tones. They have intact speech production, reading, and writing. Their poor repetition means that they can repeat single vowel sounds but not otherwise. They are also better at perceiving slower presentations

What are the clinical characteristics of pure word deafness? In terms of our cognitive model, where is the damage localized? Define the two modes of auditory perception. What have neuropsychological investigations told us about the nature of the primary processing deficit associated with this disorder?

Pure word deafness patients have damage to auditory analysis system, so they have difficulty in parsing sound waves into component phonemes. Pure word deafness causes impaired speech comprehension and poor repetition. Patients complain that words have no meaning. They can hear but not understand, meaning they have normal hearing on audiometric testing and normal performance on perceiving pure tones. They have intact speech production, reading, and writing. Their poor repetition means that they can repeat single vowel sounds but not otherwise. They are also better at perceiving slower presentations. Shankweiler & Studdert-Kennedy (1967) describe two modes of auditory perception: the general auditory mode and speech-related phonetic mode. They decided both hemispheres are capable of perceiving in the auditory mode. With steady-state acoustic signals, there is no hemispheric advantage to either side. They argue that the phonetic mode is a function of the left hemisphere and is necessary for accurate perception of rapidly changing acoustic signals that specify consonants. When you present a consonant-vowel stimulus, in healthy adults you see a right ear advantage (contralateral, so left hemisphere). This suggests that there is something special about the left hemisphere processing of the auditory signal defined in language. Experiments Albert & Bear (1974) tested their patient by speaking three digits either rapidly with no pause between or at a slower rate, and the patient would have to repeat back. If you think why they are able to comprehend it at all, for digits 1-9, most are discriminable just by their vowel sounds (there is a difference between ability to perceive vowels and consonants). At a slow rate, the patient had 95% correct. At a fast rate, they had 50% correct. Patients identify vowels spoken to them much better than consonants. One patient had good performance at speaking single spoken vowels (a, e, i, o, u) but their performance deteriorated if you added a consonant to the vowel. When you plot the acoustic wave/ the frequency spectrogram, vowels are represented by steady state characteristic frequencies and their lengths are within 100-150 ms up to 400 ms, whereas if you look at consonant-vowel combinations, especially stop consonants (pa, da, ka) contain early rapid formant transition, and in these consonant-vowel combinations, the vowels are characterized by the steady state performance but the consonants are characterized by rapid frequency changes within the first 40 ms of the stimulus onset. Patients may be unable to make fine temporal discriminations necessary for tracking rapidly changing acoustic signals, which is turn in necessary for discriminating between various spoken consonants. Other evidence comes from a dichotic-listening task for Albert & Bear (1974) patient. The patient did a dichotic listening task where they had to tell back either what was happening in their right or left ear. For the monaural task where there was only sound in one ear, their results were 10/10 for the left ear, and the results were 9/10 for the right ear. For the dichotic task when they were told to attend to the left ear, their results were 17/20. When told to attend to the right ear in the dichotic task, their results were 0/20. So, there is right ear extinction in word deaf patients when there is competing auditory information. Is the left hemisphere deficit specific to speech stimuli? If you give rapidly changing auditory sounds like clicks, you should see that discrimination performance in word deaf patients is comparable to healthy adults. If you vary the time between clicks, you will be able to discriminate two clicks as being separate entities if the time between them is 2-3 ms, otherwise they are fused as a single entity. Word-deaf patients are impaired in distinguishing clicks, based on studies from Albert & Bear (1974) and Auerbach et al. (1982). You can think of the left hemisphere as being more capable than the right in distinguishing rapidly changing acoustical patterns. Patients can also utilize lip movements as well as linguistic context information to aid in their comprehension. Patients make extensive use of movements to help them understand speech ("if I go blind I won't hear anything"). Albert & Bear looked at patients' ability to understand digits at fast and slow rates with and without lip reading. There is an increase from 95 to 98 when allowed to lip read in the slow condition and improvement from 50 to 80 with lip reading in the fast condition. In conversation, switching from one topic to another causes comprehension in patients to decrease. This suggests that one deciphers acoustic signal based on semantic context (words are not presented in isolation but rather with context). Sapphirine (?) et al. had patients listen to lists of words. The lists were either small sets of categories (animals, vegetables) or completely unrelated words. The patient was better at perceiving the lists with some sort of structure/semantic relation than the ones that were unrelated. Healthy adults will also use lip movements and semantic context to understand words presented in a background of white noise. The difference between patients and HC is that for HC, the noise is created artificially or in the natural environment and we can filter this sound out, but for patients, the auditory analysis system has been damaged so their function is halted at the initial stage

Describe Baddeley & Hitch's study with healthy subjects. What do their results tell us about the role of short-term memory stores in working memory?

Researchers began questioning if short-term memory and working memory were synonymous. They thought that if they were the same and the same module is playing a role in both, then there should be a lot of interference in performing the two tasks simultaneously. Baddeley & Hitch (1974) tried to test this hypothesis by having subjects solve logic problems (True/False questions about "BA") while simultaneously having them repeat a sequence of numbers held in working memory, such as 73192. Baddeley & Hitch timed how quickly they could solve the true/false problems and varied the number of digits the subject had to repeat (the dependent measure was the number correctly answered in 3 minutes). They found that the number of correctly answered problems did not change whether or not the vocalization task was occurring simultaneously. When the span of numbers reached six digits, there was evidence of slowing in reasoning ability. In general, there is not the evidence of profound interference that you would expect if these two tasks used the same module. This experimental result led Baddeley & Hitch to make their original model of working memory in 1974. It is a three-component model of working memory which was later modified. It led to a re-formalization of the concept of what short-term memory is. They proposed that there was a core system, the central executive, and separate subcomponents, the visuospatial sketchpad and phonological loop. Working memory represents the limited capacity store for retaining information over the very short term and for performing mental information for the content in working memory. The idea of a unitary store is insufficient to explain all the maintenance of processing over a short period of time with things that we are currently holding in memory. The model helps to separate the subprocesses.

Describe the experimental evidence that the auditory phonological loop is important for speech comprehension and language acquisition? What types of sentence constructions do short-term memory patients have particular difficulty comprehending? Does the auditory phonological loop play a significant role in speech production?

Researchers tried to discover the function of the phonological loop in Baddeley & Hitch's model of working memory. Suggestions for the function of the phonological loop included speech production (disproved), speech comprehension (accurate), and language acquisition (accurate). One suggestion for the function of the phonological loop was that it was responsible for speech production. They suggested that information must be retained in phonological form for a short period of time in order to line up utterances in a compiled form (a smooth flow of spontaneous acoustical information) prior to articulation. Shallice & Butterworth (1977) tested this theory using Patient JB, a STM syndrome patient. They theorized that if the phonological loop were responsible for speech production, STM syndrome patients would show difficulty with spontaneous speech, making phoneme ordering errors when speaking too quickly. To test this, they did a statistical analysis of conversation speech of JB, but it was comparable to the healthy controls, so this theory was disproved. Another suggestion for the function of the phonological loop was that it was responsible for speech comprehension. They suggested that you have to maintain representation in the acoustical level until you have been able to disambiguate the clauses in the sentence for long enough to interpret what has been said. Vallar & Baddeley (1984) assessed Patient PV's ability to repeat back sentences. She had a short-term store capacity of six words. They gave three different conditions to see if she could repeat sentences that exceeded her span. Condition A was sentences within her span. Condition B exceeded her span by about 10 words. Condition C was about the same length as condition B but was made incorrect by modifying the linear arrangement of the words so they were part of the same semantic code. PV had comparable performance to HC for conditions A and B but dropped in performance for condition C. This suggested that the phonological loop was involved in (visual) speech comprehension. Another experiment that showed this was Saffran & Marin's (1975) experiment on Patient IL. They had him repeat back sentences verbatim immediately after hearing them. When the sentences exceeded his capacity, he would have omission and substitution errors, paraphrases with similar meanings, semantic reversal of the sentences, suggesting that the phonological loop does something fundamental in terms of (auditory) speech comprehension. The phonological loop functions to maintain information in a lexical, syntactical surface structure until you have been able to understand its meaning. It may serve also as a general purpose backup role for comprehension—if you have too much novel information compressed, you are going to engage immediate working memory much more in the novel situation as you are trying to understand. The phonological loop can also help in terms of interpretation under noisy conditions. Think of the phonemic restoration effect in noisy environments-you fill in the gaps of things you did not hear by keeping phonemes in your phonological loop until you are able to extract the meaning. Finally, Baddeley, Papagno & Vallar (1988) tested Patient PV using a paired associate task to test the function of the phonological loop in language acquisition. In PV's native language, she performed comparably to healthy controls on this task. When the word was paired with a word in a language she did not know, she could never learn the association. This shows that the phonological loop is necessary for language acquisition.

Retrieval-induced vs. directed forgetting

Retrieval-induced: memory phenomenon where remembering causes forgetting of other information in memory, directed: experimental procedure where individuals are told that they can forget some of the information being presented to them

Ribot's law

Ribot's law is that amnesic patients have generally better memory for early life than later life events (temporal gradient).

Mismatch negativity

The MMN is usually evoked by either a change in frequency, intensity, duration or real or apparent spatial locus of origin. The MMN can be elicited regardless of whether the subject is paying attention to the sequence arises from electrical activity in the brain The mismatch negativity (MMN) is a brain response to violations of a rule, established by a sequence of sensory stimuli (typically in the auditory domain). The MMN reflects the brain's ability to perform automatic comparisons between consecutive stimuli and provides an electrophysiological index of sensory learning and perceptual accuracy.

Paired associate learning task

The Wechsler paired-associate learning task presents patients with pairs of words such as "cloud, banana." Twenty minutes later, the patient would be prompted with "cloud" and have to reply "banana." This tasks assesses long-term memory, so STM syndrome patients perform comparably to healthy controls on it.

Plasticity

The ability of the brain to change throughout an individual's life (in Vargha-Khadem's patients, it was suggested that the patients compensated for their deficits because they were young, so they had more neuroplasticity)

Recall

The action or fact of calling someone or something back. Recall in memory refers to the mental process of retrieval of information from the past. ... There are three main types of recall: free recall, cued recall and serial recall. Psychologists test these forms of recall as a way to study the memory processes of humans and animals.

Spoonerisms

a verbal error in which a speaker accidentally transposes the initial sounds or letters of two or more words, often to humorous effect, as in the sentence you have hissed the mystery lectures, accidentally spoken instead of the intended sentence you have missed the history lectures.

Describe the organization and functional characteristics of the component modules within Baddeley & colleagues model of working memory.

The original model: The central executive is the controller of the subordinate system. The phonological loop holds the acoustical information. The visuospatial sketchpad parallels the phonological loop and permits information storage of visual or visuospatial codes. In terms of the processing involved for central executive, it is the control or command center that presides over the interactions of the visuospatial loop and the phonological loop. The central executive's job is to coordinate processing in working memory. The original model is insufficient; one problem is the serial position effect—how is serial order of information that you're holding in working memory encoded? How do the loops interact with long-term memory? How do the two loops interact with each other? How does "chunking" occur? The span of "7 +/- 2" is not always right because mnemonics can aid with increased retention, suggesting that long-term memory can be used to aid an increased capacity of short-term memory—how does this happen in terms of this model? Revised model: Baddeley & Hitch reconceptualized the model in 2003 and added modules including long-term memory. They added another loop called the episodic buffer, which is a limited-capacity store that binds together information to form integrated episodes. It is attentionally controlled by the central executive and accessible to conscious awareness. You can think of the episodic buffer as the global workspace which the central executive works on. You bring information up to the immediate memory that you are actively manipulating and that is what the buffer does.The model differentiates between fluid systems and crystallized systems—the visuospatial sketchpad, episodic buffer, and phonological loop are fluid systems while visual semantics, episodic LTM, and language are crystallized.

Primacy vs. recency effect in serial position curve

The primacy region is the area of the graph where the patient is read the first few terms. This information is encoded into long-term memory because the patient had time to rehearse the terms. The recency area is the area of the graph where the patient was read the last few terms. These terms are in working memory, but only as many as can be stored.

Describe the functions of the "what" and "where/how" routes in speech perception. What are the proposed neural routes for lexical-semantic processing and auditory-motor correspondence?

The primary auditory cortex is located in Heschl's gyrus. As in visual perception, auditory perception has "what" versus "where"/"how" routes. The "what" route is the ventral route to the primary auditory cortex along the temporal lobe. The "what" route recognizes speech acoustically rather than motorically and is important for speech comprehension and makes contact with semantic knowledge representation. Broca's aphasic patients have difficulty producing language but can understand auditory information. The "how" route is the dorsal route involving parieto-frontal circuit. The dorsal route recognizes speech motorically and is used to say and learn unfamiliar words. Part of Wernicke's area responds to silent articulation (by speaker) and also viewing lip movement in others. There is evidence for phonological STM in angular gyrus which may be refreshed by frontal rehearsal mechanisms (e.g. phonological loop component of working memory). Deficits in repeating and learning new phonology are linked to phonological STM impairments, which is a deficit in the "how" route, intact "what." Patients with deep dysphasia cannot repeat nonwords and make semantic errors in repetition (e.g. hear "cat," say "dog"), which is a deficit in "how" route, so they rely on impoverished "what." In terms of cortical deafness that arises from bilateral damage to the primary auditory cortex, just as in vision there are subcortical routes that support some residual auditory processing (like blindsight). Patients may have selective impairments such as difficulty identifying speech but being able to identify environmental sound.

Define what sound is and describe its physical properties and how they relate to their psychological properties.

There are different classes of auditory stimuli such as music, voices, speech, environmental sounds and dissociations in how we process each. The most simple sound is a pure tone (sine wave). Most sounds are combinations of sinusoidal waves of different amplitudes and phases. There are pure tones versus complex sounds. Like in vision, there is correspondence to physical versus psychological properties of the sound. The frequency relates to some degree to the pitch and the amplitude relates to some degree to loudness. There are interactions between pitch and loudness. If there is a low frequency sound, it sounds lower if you make it louder, and if there is a high frequency sound, it sounds higher if you make it louder, which implies they are not purely separable and implies they are not processed independently by the brain.

Broca's aphasia

There are two categories of speech: omission or commission. In terms of non-fluent speech in Broca's aphasia, there is often agrammatism (inadequate sentence production, attempts to make a sentence but the skeleton of the sentence is missing). For example, a patient said "cookie jar...fall over...chair...water...empty" to describe the cookie jar image, so they understand content but cannot make a coherent picture. Individuals with Broca's aphasia have trouble speaking fluently but their comprehension can be relatively preserved. This type of aphasia is also known as non-fluent or expressive aphasia. Patients have difficulty producing grammatical sentences and their speech is limited mainly to short utterances of less than four words. Producing the right sounds or finding the right words is often a laborious process. Some persons have more difficulty using verbs than using nouns. A person with Broca's aphasia may understand speech relatively well, particularly when the grammatical structure of the spoken language is simple. However they may have harder times understanding sentences with more complex grammatical construct. For example the sentence "Mary gave John balloons" may be easy to understand but "The balloons were given to John by Mary" may pose a challenge when interpreting the meaning of who gave the balloons to whom. Individuals with this type of aphasia may be able to read but be limited in writing. Broca's aphasia results from injury to speech and language brain areas such the left hemisphere inferior frontal gyrus, among others. Such damage is often a result of stroke but may also occur due to brain trauma. Like in other types of aphasia, intellectual and cognitive capabilities not related to speech and language may be fully preserved.

McGurk illusion

There is a modulation of what you hear based on what you see. Hearing the word "ba" and seeing a person articulate "ga" makes you hear something different, which is the McGurk illusion (when you listen to the clip with your eyes closed versus eyes open you hear different things). The clip has the audio /baba/ but their lips say /gaga/ so when looking and hearing one may hear /dada/ or /thatha/

Describe the organization and functional characteristics of the component modules within the informational processing model of speech perception described in lecture.

This model roughly corresponds to "what" and "how" pathway. Auditory analysis system is the first component which attempts to identify phonemes in sound wave. The auditory input lexicon contains memories of sound patterns of known words. The semantic system contains the meaning of heard known words. The speech output lexicon can bypass the semantic system and allow for repetition of words without accessing word meanings. The phoneme level can bypass the lexicon routes and allows for repetition of nonwords for which there are no entries in the lexicon.

What are the characteristics of a patient who has phonological auditory agnosia? In terms of our model, where is their damage localized?

When there is damage in the connection between the auditory analysis system and the phoneme level, this is called auditory phonological agnosia. The auditory phonological agnosia patient is patient JL, a 58 year old man studied by Beauvois et al. (1980). JL had normal spontaneous speech, good reading aloud and spontaneous writing, but he complained of difficulty understanding spoken language, especially new words. He had no difficulty with old, familiar words. The patient would approximate a nonword told to him by repeating a similar, real word. His performance on the auditory lexical decision task was perfect and he could read and pronounce non-words. If you think about the role is to shunt the phonemic description of familiar words directly from the auditory analysis stage to the phoneme level to produce speech. If patient JL has a disrupted connection here, his only way of repeating speech would be through a longer route of the auditory analysis system, auditory input lexicon, speech output lexicon, and back to the phoneme level. This explains the patient's strategy when given words that aren't in his lexicon (he comes up with words in his lexicon that best approximate the word). Any auditory percept is made up of a sequence of phonemes in a particular order and timing.

What role does the prefrontal cortex play in long-term memory?

While some researchers emphasize the pathway from the hippocampus to the mPFC as supporting memory consolidation, there is considerable converging evidence that the prefrontal cortex contributes to memory through cognitive or strategic control over memory retrieval processes within other brain areas. The mPFC appears to be particularly involved with memory retrieval and consolidation. Patients with prefrontal damage do not have severe impairments in standard tests of event memory, but deficits resulting from prefrontal damage are apparent when memory for target information must be obtained under conditions of memory interference or distraction. Even when learning two lists of unrelated associations, in prefrontal patients, memory for one list is compromised by intrusions from the other, suggesting that the prefrontal cortex controls memory retrieval by selecting memories relevant to the current context and suppressing irrelevant memories. The hippocampus is viewed as forming and retrieving specific memories, while the prefrontal cortex accumulates features of related memories that compose the 'context' of a set of connected experiences, such as a list in which a set of words appeared, a common location where several events occur, or a common set of ongoing task rules that govern multiple memory decisions. When subsequently cued to a context, the prefrontal cortex is viewed biasing the retrieval of context-appropriate memories in the hippocampus as well as other brain areas.

Phoneme

any of the perceptually distinct units of sound in a specified language that distinguish one word from another

Allophones

any of the speech sounds that represent a single phoneme, such as the aspirated k in kit and the unaspirated k in skit, which are allophones of the phoneme k

Loudness

attribute of auditory sensation in terms of which sounds can be ordered on a scale extending from quiet to loud

What is "constructive memory"? How do memory distortions (false memories and confabulations) arise?

constructive memory: An apparent memory of an event that did not actually happen, unconsciously constructed to fill a gap. Age does not necessarily lead to source amnesia and source recognition errors, rather the interaction between age and overall executive function performance determines this. Confabulation is distinct from pathological lying because it is driven by them not monitoring or attending to their environment as opposed to intentional deception. Butler et al., (2004) did a study looking at the Deese-Roediger-McDermott paradigm which has been used in many studies to induce false memories. Subjects are presented with a list of highly semantically related words and then presented with critical lure words, which are semantically related to the list words but not actually on the list. Depending on the list, you can see identifying related lures as up to 55%. Healthy young and old adults were presented with 36 lists of 15 words chosen for their high probability of inducing false recall. A smaller portion of the list had a low probability of inducing false recall. They compared performance on the false recall of related lures to their actual performance on two tests that assess frontal lobe function, the Wisconsin Card Sorting Test and the Verbal Fluency test (FAS test). The subjects that did the study included a group of 18 younger adults with slightly less education than the older adults (vocab tests are a proxy measure of IQ), so older adults do slightly better. There is more induction of false recall in the older adults than the younger adults. The researchers separated the group based on their performance on the two frontal lobe executive function tests. The lower performing group of 17 people and the higher performing group show difference on the frontal lobe tests but not any other area of performance. Older adults with high frontal lobe function had similar performance to younger adults, but the older adults with lower frontal lobe function show many more false memories and their actual absolute level of performance on the studied items is poor. Overall, aging is not very damaging to mental function.

Missing fundamental phenomenon

despite not having the lowest frequency, you can still perceive it

Interaural differences

difference in arrival time of a sound between two ears. It is important in the localization of sounds, as it provides a cue to the direction or angle of the sound source from the head

Formants

each of several prominent bands of frequency that determine the phonetic quality of a vowel. In speech science and phonetics, a formant is the spectral shaping that results from an acoustic resonance of the human vocal tract. However, in acoustics, the definition of a formant differs slightly as it is defined as a peak, or local maximum, in the spectrum

Amusia

inability to recognize musical tones or to reproduce them. Amusia can be congenital (present at birth) or be acquired sometime later in life (as from brain damage). Amusia is composed of a- + -musia and literally means the lack of music. Also commonly called tone deafness. Congenital amusia/tone deafness affects about 4% of the population (unclear what the impairment is, but they can still do rhythm analyses and identify melodies).

Auditory stream segregation

perceptual grouping of sounds, to form coherent representations of objects in the acoustic scene, and is a fundamental aspect of hearing and speech perception The auditory environment needs to be segmented into different auditory objects in different locations. Naatanen et al., (2001) suggest that the auditory cortex creates a sensory memory to enable this process, which happens pretty early on (mismatch negativity (MMN) effect). With the onset a new stimulus, you see a reaction about 100-200 ms after the onset of the stimulus. Cusack (2005) finds evidence for the role of the parietal cortex in stream segmentation, finding that you see a dissociation for perceptually ambiguous auditory stimuli (when presenting "clip clop," it can be interpreted as one auditory stream or as two separate streams, implying the role of the parietal cortex).

Cocktail party problem

phenomenon of the brain's ability to focus one's auditory attention (an effect of selective attention in the brain) on a particular stimulus while filtering out a range of other stimuli, as when a partygoer can focus on a single conversation in a noisy room. Other evidence comes from a dichotic-listening task for Albert & Bear (1974) patient. The patient did a dichotic listening task where they had to tell back either what was happening in their right or left ear. For the monaural task where there was only sound in one ear, their results were 10/10 for the left ear, and the results were 9/10 for the right ear. For the dichotic task when they were told to attend to the left ear, their results were 17/20. When told to attend to the right ear in the dichotic task, their results were 0/20. So, there is right ear extinction in word deaf patients when there is competing auditory information.

Confabulation

production of fabricated, distorted, or misinterpreted memories about oneself or the world, without the conscious intention to deceive. Confabulation is distinct from pathological lying because it is driven by them not monitoring or attending to their environment as opposed to intentional deception.

Syntax

set of rules, principles, and processes that govern the structure of sentences in a given language, usually including word order

Fundamental frequency

the lowest frequency which is produced by the oscillation of the whole of an object, as distinct from the harmonics of higher frequency

Tonotopic organization

spatial arrangement of where sounds of different frequency are processed in the brain. Tones close to each other in terms of frequency are represented in topologically neighbouring regions in the brain. Just as with retinotopic organization in visual processing, there is a tonotopic organization in audio processing. The neurons that are sensitive to different frequencies are adjacent to each other

Spectrogram

spectrogram showing the frequencies against time of the acoustical signal someone saying a particular sentence, You have to be able to parse and understand it. The sentence is and the intensity tells you "Joe took father's shoe bench out." There are gaps in the acoustical signal but they don't necessarily correspond to where the gaps are in the sentence. This spectrogram would look different if it were said faster or someone with a different accent said it, so there is an infinite amount of variability of this sound wave and you will be able to understand a variety of different speakers speaking at different speeds and intonation.

Pragmatics

the branch of linguistics dealing with language in use and the contexts in which it is used, including such matters as deixis, the taking of turns in conversation, text organization, presupposition, and implicature

Imageability

the ease with which a word gives rise to a sensory mental image may influence storage and processing of words in the mental lexicon, together with other factors such as age of acquisition, frequency, word length and phonological properties.

Pitch

the quality of a sound governed by the rate of vibrations producing it; the degree of highness or lowness of a tone. There are interactions between pitch and loudness. If there is a low frequency sound, it sounds lower if you make it louder, and if there is a high frequency sound, it sounds higher if you make it louder, which implies they are not purely separable and implies they are not processed independently by the brain

Voicing

utter (a speech sound) with resonance of the vocal cords (e.g. b, d, g, v, z )

Semantic/verbal paraphasia

word errors bearing clear semantic relationship to picture name (call a butterfly a spider)

Word paraphasia

word errors bearing no semantic relationship to picture name (call a desk "teeth")