Chapter 18 + 27

Rhinal Cortices & Hippocampus

Object recognition (factual or semantic knowledge) depend on these cortices while contextual knowledge (autobiographic, or episodic knowledge) depends on this structure

NTs for Alzheimers

Researchers thought that NT ACh would be a successful treatment for Alzheimer's --> disease is too complicated, because transmitters other than ACh are changed in Alzheimers as well. Noradrenaline, dopamine, and serotonin are reduced, as are the NMDA and AMPA receptors for glutamate

Long Term Explicit Memory

Includes episodic memory, autonoetic awareness of time, and semantic memory

Global Anterograde Amnesia

A condition that leaves one impaired in spatial and topographic learning and in learning about the events that take place around them, including the death of loved ones (Patient HM)

Herpes Simplex Encephalitis

A condition where temporal-lobe damage causes severe memory impairments. Ex: patient Boswell --> had anterograde amnesia and severe retrograde amnesia (couldn't retrieve info from any part of his life history) but maintained his typical intelligence and language Insula is implicated in retrograde amnesia

Alzheimers

A disease that exhibits a progressive loss of cells and the development of cortical abnormalities. Characterized first by anterograde amnesia and later by retrograde amnesia as well. The medial temporal cortex is the first place to show change Damage to the medial temporal cortex related to anterograde amnesia and damage to other temporal association and frontal cortical areas is related to retrograde amnesia

Episodic (autobiographic) Memory

A person's recall of singular events/life experiences that are centered on the person himself

Time-Dependent Retrograde Amnesia

A result of brain injury that causes a transient loss of consciousness followed by a short period of confusion and retrograde amnesia

Panic Disorder

A type of pathology where people show marked anxiety but cannot identify a specific cause

Autonoetic Awareness

A type of self-knowledge that provides us with a sense of continuity. Allows us to travel in subjective time, either into the past or into the future.

Motor Cortex Plasticity

Acquisition of a skill is associated with the primary motor and supplementary motor cortices and the pulvinar nucleus of the thalamus. Performance is associated with the motor cortex, basal ganglia and cerebellums Acquiring implicit knowledge requires cortical plasticity not required for explicit-memory performance

Short Term Memory

Also called working memory or temporary memory. Is a neural record of recent events and their order. We use it to hold sensory events, movements, and cognitive information, such as digits, words, names, etc. --> A lesion to the left posterior-temporal lobe = almost total inability to repeat verbal stimuli such as digits, letters, words, and sentences

Paired Helical Filaments

Also known as neurofibrillary tangles --> are found in the cerebral cortex and the hippocampus and are related to tau protein.

Gist

Describes the objective reconstructing of a memory. It allows us to anticipate and respond to situations in the future in ways that benefit from our past experiences.

Emotional

During _______ memory, the amygdala connects to autonomic systems, that control blood pressure and heart rate, and to the hypothalamus, which controls hormonal systems. Damage to amygdala gets rid of _______ memory but doesn't affect implicit or explicit memory

Implicit

During _______ memory, the basal ganglia gets projections from neocortex & dopamine cells in the substantia nigra --> then sends projections through the globus pallidus and ventral thalamus to the premotor cortex

Explicit Memory

Events and facts that you can spontaneously recall

Hippocampal region

In case of damage to this region, this is what we know: 1) anterograde memory is more severely affected than retrograde memory 2) episodic memories are more severely affected than semantic memories 3) autobiographic memory is especially severely affected 4) "time travel" is diminished

Evoking Negative Emotions

In fear conditioning, a noxious stimulus is paired with a neutral stimulus to elicit an emotional response. Circuits of the amygdala mediate fear conditioning, and circuits of the cerebellum mediate eye-blink conditioning.

Dendritic Arborization

In patient's with Alzheimer's disease there's a loss of ________ which leads to cortical atrophy. Degradation of hippocampal neurons shouldn't happen with age

Cerebellum

This structure plays a role in nonconscious learning known as classical conditioning. Has to do with motor learning.

Semantic Memory

Knowledge about the world - all non-autobiographical knowledge (the ability to recognize family, friends, information learned in schools, reading, etc)

Long Term Emotional Memory

Like implicit memory, this type of memory for the affective properties of stimuli or events relies on bottom-up processing. But this type of memory is arousing, vivid, and available on propting PLUS has the intentional, top-down element of explicit memory

Retrograde Amnesia

Loss of memories that occurred prior to injury

Long Term Memory

Made up of three general types: explicit, implicit, and emotional

Episodic Memory

Memories for personal experiences

Emotional Memory

Memories for the affective properties of stimuli or events (your first kiss) is vivid and has characteristics of implicit and explicit memory

Semantic Memory

Memory for facts

NT Activating Systems in Memory

NTs cholinergic, serotonergic, and noradrenergic--> they go from the brainstem to the forebrain Loss of cholinergic cells is related to Alzheimer's disease

Implicit Memory

Nonconscious memories (ex: riding a bike) that consist of learned skills, conditioned responses, and events recalled on prompting

Fimbria Fornix

Pathway through which hippocampus connects to brain reciprocally --> specifically connects to the thalamus, prefrontal cortex, basal ganglia, and hypothalamus

Perforant Pathway

Pathway through which the hippocampus connects to the brain reciprocally --> specifically connects to the posterior temporal cortex

Right Ventral Prefrontal Cortex

Patient ML was amnesic for EPISODIC experiences --> showed damage to the ___________ and underlying white matter, including the uncinate fasciculus, a fiber pathway that connects the temporal lobe and ventral prefrontal cortex.

Patient VC

Patient whose hippocampus was removed and had retrograde amnesia that covered his entire life before lesion. Suggests that the complete loss of the hippocampus results in complete retrograde and anterograde amnesia for explicit info from all periods of life

Interference Task

Patients had to read five different lists of 12 words each and then recall as much as they could immediately after. Controls showed a decline from list 1 to list 4 in the number of words recalled correctly --> exhibited proactive interference (the earlier lists interfered with learning new info). But on list 5 they recalled as many words as they did from list 1, thus demonstrating a release from proactive interference

Superior Autobiographical Memory

People who display this can virtually recall every event in their lives, usually beginning around age 10, and can often describe any episode --> due to increase in gray matter in temporal & parietal lobes + increased fiber projections between the temporal lobe and the frontal cortex

Fugue State

Someone is in this state when their memory loss of personal history is sudden and transient. Result of a temporary suppression of medial-temporal-lobe memory systems

Theories of Amnesia

System Consolidation Theory, Multiple-Trace Theory, and Reconsolidation Theory

Spared Brain Areas in Alzheimers

The brainstem, cerebellum, and spinal cord

Anterograde Amnesia

The inability to acquire new memories

Childhood (infantile) Amnesia

The inability to remember events from our infancy or early childhood

Entorhinal cortex

The limbic system undergoes the most severe degenerative changes in Alzheimer's disease, and of the limbic structures, _______ cortex is affected the most and earliest. The _______ cortex relays info from the neocortex to hippocampus and related structures and is then sent back to the neocortex. Damage to the _______ is associated with memory loss, which is most likely caused by the degenerative changes that take place in this limbic area

Long Term Implicit Memory

The memory of learned skills, conditioned reactions, and short-term events that is nonconscious and unintentional Here, processing bottom-up and depends on sensory and motor information --> this type of memory depends upon many of the neural structures that constitute the dorsal stream action pathway

Implicit Memory

The neural basis of this type of memory includes the entire neocortex and basal ganglia structures (caudate nucleus and putamen).

Basal Ganglia

This structure plays a role in implicit memory + Hungtion's disease has to do with cellular degeneration of this structure Patients with Huntington's are impaired in the implicit mirror-drawing tasks, but unimpaired in an explicit task Parkinson's disease patients have implicit memory deficits but can be helped by L-dopa (dopamine plays a role in this structure)

Explicit

The underlying neural substrates of ______ memory are mostly found in the temporal lobe --> includes hippocampus, the rhinal cortices, and the prefrontal cortex. The regions that make up the _______ memory circuit receive input from the neocortex and from the ascending systems in the brainstem, including the acetylcholine, serotonin, and noradrenaline activating systems

System Consolidation Theory

Theory that hippocampus consolidates new memories, a process that makes them permanent. When consolidation is complete, memories are stored elsewhere in the brain. Older memories survive because they are moved elsewhere

Reconsolidation Theory

Theory that memories rarely consist of a single trace or neural substrate but are revised each time they are recalled or shared or elaborated on with others. Each use of a memory is associated with a new place of storage, so there are many new cues

Neuritic (Amyloid) Plaques

These are found in the cerebral cortex and result from the accumulation of tau protein. Their increased concentration in the cortex is related to the magnitude of cognitive deterioration

Gaffan & Gaffan

These doctors described patients who sustained damage to the fimbria fornix pathway but spared hippocampus --> pathway connects the hippocampus to the frontal lobes and brain stem. These patients displayed retrograde and anterograde amnesia similar to that seen in patients with temporal-lobe damage

Dorsal and Ventral Streams

These streams go from the parietal cortex and temporal lobes & project to different prefrontal cortical regions that support two kinds of short-term memory

Temporal Cortex

This cortex = bordered by the rhinal fissure and includes the perirhinal cortex and the entorhinal cortex, which provides a major route for neocortical input to the hippocampal formation --> these regions are often damaged in patients with medial-temporal lobe lesions

Korsakoff's Syndrome

This illness has 6 major features: 1) anterograde amnesia 2) retrograde amnesia 3) confabulation (patients produce plausible stories about past instead of admitting to memory loss) 4) meager content in conversation 5) lack of insight 6) apathy (patients loss interest in things quickly) The cause of this illness is a thiamine (vitamin B) deficiency resulting from prolonged intake of large quantities of alcohol --> kills cells in the medial part of the diencephalon, including the medial thalamus and mammillary bodies of the hypothalamus

Hippocampus

This is a limbic structure that extends from the lateral neocortex of the medial temporal lobe toward the brain's midline --> has a tubelike appearance. It's made up of two gyri, ammon's horn (pyramidal cells) and the dentate gyrus (stellate granule cells). This structure is reciprocally connected to the rest of the brain through the perforant pathway and the fimbria fornix

Dementia

This is an acquired and persistent syndrome of intellectual impairment. It can either be a major neurocognitive disorder (where there's evidence of substantial cognitive decline from a previous level of performance) or mild neurocognitive disorder (modest cognitive decline from a previous performance level) Alzheimer's is the most prevalent example of this

Insula

This structure is implicated in retrograde amnesia and is active when participants perform a well-practice verbal task but inactive when they perform a novel verbal task

Multiple-Trace Theory

This theory accounts for individual differences in amnesias. 1) In any learning even memories of many types are encoded in parallel in different brain locations. 2) Memories change throughout a person's life as they are recalled, reevaluated, and restored. 3) Different kinds of memory, being stored in different locations, are differentially susceptible to brain injury

Hippocampal and frontal cortical injury

This type of injury causes people to lose self-knowledge and have difficulty in daily living resulting from a deficit of behavior self-regulation and the ability to profit from past experience in making future decisions

Short Term Memory

This type of memory may be related to ventral (object-recognition) or dorsal (motor) streams of sensory processing. Both streams project to the prefrontal cortex. This type of memory for motor and for object info is mediated by locations defined by the dorsal and ventral streams to two different regions of the frontal cortex