Psych 316 Exam 3
William James
"An object which has been recollected... is one which has been absent from consciousness altogether, and ... is brought back ... from the reservoir in which, with countless other objects, it lay buried and lost from view. But an object from primary memory is not thus brought back; it never was lost; its date was never cut off in consciousness from that of the immediate present moment. In fact it comes to us as belonging to the rearward portion of the present space of time, and not the genuine past.
treisman's theory
(more accurate than Broadbent's) 1) treisman proposed a theory in which the filter reduces or attenuates (but does not completely block) the analysis of the unattended information 2) stimulus analysis proceeds in a hierarchy starting with analysis of physical features, syllables, letters, words, grammar, and meaning. if cognitive capacity is overloaded, the later stages of analysis are omitted. 3) *detection thresholds of stimuli consistent with the current goals are lowered*
focused attention vs. divided attention
*focused:* paying attention to one thing at a time. it is studied by presenting people with 2 or more stimulus inputs simultaneously and instructing them to respond to only one. *divided:* multiple stimuli are presented and subjects must attend to and respond to all stimuli.
attentional filtering based on physical characteristics
*physical characteristics help filter* 1) two audio streams will be played simultaneously 2) try to hear all digits spoken 3) same pitch vs. different pitch - child speaking (high pitch) vs. adult speaking (lower pitch)
two major differences between broadbent and treisman DIFFERENCE #2
- broadbent suggests that the filter blocks out all unattended stimuli. the unattended stimuli do not receive any processing if attentional capacity is overloaded. - treisman suggests that the attenuator does not block out processing, it simply gives preference to the attended stimuli. if there is enough cognitive resources, the unattended stimuli can get processed, too.
two major differences between broadbent and treisman DIFFERENCE #1
- broadbent suggests there is an attentional filter very early in processing stream, which filters out stimuli based on physical characteristics. - treisman suggests that there is an attenuator that gives processing preference to stimulus based on what we are trying to do at the moment. each stimulus has a different activation threshold. *attention is goal directed*
predictions about interference between tasks
- if resources are task general, then it shouldn't matter what is the secondary task, as long as both the primary and secondary tasks demand attentional resources, interference will occur. - if resources are task specific, then the nature of the secondary task will determine the amount of interference in dual task situations
Sperling's Partial Report
-A tone is played after the array disappears. -Report items from one row based on tone pitch. A high pitch tone means the top row, a medium pitch tone means the middle row, and a low pitch tone means the bottom row.
Partial Report
-If capacity is 4.3 letters out of three rows, then asking subjects to report one row should, on average, get you 1.4 letters. -Surprisingly, subjects could report an average of 3.04 letters from a row with 4 letters!
The Modal Model (Atkinson & Shiffrin (1968))
-Information is taken in at the senses and receives some early, initial analysis. -The information then enters into short-term, working memory (WM). -The information is maintained by some active process such as rehearsal. -Prolonged maintenance of information in STM allows that information to be transferred to long-term memory (LTM), or the information is lost. -During retrieval, information is transferred from LTM to WM.
Sperling's Method Findings
-When the array had 4 or fewer letters, subjects reports were near perfect. -As the number of letters presented increased the number subjects could report averaged about 4.3 items regardless of the array size. -What do these findings suggest about how much we can see from a single, quick glance? -Our capacity is ~ 4 units of information?.
inattentional blindness
-during the 4th trial, the fixation changed to a triangle, a square, or a cross. -89% of subjects failed to notice the change -is 200 ms just too fast for people to see change? -no because when subjects were told they should report any other stimuli that appeared on the screen before they started the task, over 90% of them noticed the change. inattentional blindness cannot be attributed to a fast presentation rate because attention is not on center, there is no perception on center *with results, Mack and Rock claimed "there is no perception without attention"*
evidence for disengagement
-neglect is usually caused by parietal lobe damage - patients usually have trouble with disengagement - patients with Balint's syndrome also have trouble with disengagement
divided attention
-we can multi-task, but there is a limit -you generally have no problem talking or singing while driving, but you have major difficulties trying to listen to a lecture while studying for an exam for an upcoming class
attentional resources
-what makes the second scenario (studying and listening) more difficult? because it requires *more resources*
Moore and Egeth results
-when subjects were asked if they had noticed any pattern in the dots, none reported seeing the pattern. - subjects couldn't even pick the correct pattern out of the four - however, remarkably, results from the line length judgment task showed that indeed the *dot pattern was processed* -- because 95% of the subjects reported that the top line was longer
the name effect
1) 1/3 of subjects report hearing their own name when it is embedded in the unattended message 2) a limited amount of meaning processing is apparently possible for information that is supposed to have been filtered out 3) this is inconsistent with Broadbent's theory b/c you have already processed the meaning of your name
Mack and Rock (1998)
1) asked subjects to judge whether the length of the horizontal line or the vertical line is longer in a + sign. the entire display was then replaced by a pattern mask. 2) subjects must focus on a fixation at the center of the screen and not look directly at the + sign when it appears (200 ms)
broadbent's model evidence
1) broadbent presented subjects with a different set of 3 digits to each ear and then asked them to recall the digits -e.g. he presented 4-6-2 to one ear and 3-5-1 to the other ear 2) subjects almost always recalled the digits by ear rather than by pair. that is, they almost never recall the digits by pari such as 4-3, 6-5, 2-1, even though these numbers occur simultaneously. 3) physical characteristics is defined by ear here (not by parts)
expertise effect
1) in dichotic listening-shadowing task, Underwood asked either naive subjects or an experienced researcher to detect a target digit. 2) inexperienced subjects detected only 8% of the digits in the nonshadowed message. the researcher detected 67% of them. 3) clearly, the filter may not work as well as broadbent had assumed (expertise modulates filters effectiveness) *more you train, more it works? (broadbent)* *NO, expertise effects how filter works*
Moore and Egeth trials
1) in first three trials, the display had two lines with haphazard series of dots surrounding them (no pattern) 2) on fourth trial, the dots, together with the two lines, form the Muller-Lyer illusion (pattern)- both lines same length but think the line with the outfacing arrows is longer
Sperling's Method (immediate memory and short term memory)
1) varied number of letters 2) presented very briefly 3) report: what letters did you see?
Iconic Memory vs. Afterimage
A pattern mask can remove iconic memory even when it is presented to a different eye than the one that observed the original stimuli -- iconic memory resides in the brain and is different from afterimage.
endogenous orientation vs. exogenous orientation
Active: when attention is controlled in a top-down fashion-- *endogenous orienting* (coming from within) Passive: when attention is controlled in a bottom-up manner by external stimuli-- *exogenous orienting* (outside of us, captures our attention)
Task Specific Resources (results from Brooks)
Brooks' data are consistent with task specific resource account. that is, two tasks that use the same type of attentional resource would interfere with each other more than two tasks that use different types of attentional resource.
Central Executive
Central executive is the component that carries out resource allocation decisions and makes executive decisions. Tasks that require production and selection would require resources from the central executive. E.g., random number generation.
Chunking
Chunking increases short-term memory capacity. Trade-off: The number of chunks may be reduced as the size of chunks become larger. E.g., you may be able to maintain 7 words but only 3 or 4 sentences. Limitation: Attention and interaction with long-term memory is required, as well as greater efforts to maintain the chunks.
Savings
Ebbinghaus realized that even if he could not recall some CVC nonsense syllables, this failure might not indicate that all traces of the nonsense syllables had vanished from memory. Restudy and recite until perfect mastery. Measure number of trials to perfect recitation. % Savings = (OL - RL) X 100% divided by OL If it took 15 trials to learn originally, and 5 trials to relearn: (15 - 5) X 100% divided by 15 Savings = 67%
Origin of Memory Research
Ebbinghaus single-handedly created the field of memory research. Prior to him, memory was considered an unresearchable phenomenon. Published the book On Memory.
What is the capacity of short term memory?
George Miller The Magical Number Seven, Plus or Minus Two: Some Limits on our Capacity for Processing Information. Can we break through this STM limit?
What is memory?
Is memory one thing or is memory multiple things? Remembering events, personal past Knowing facts, general knowledge Reading, writing, typing, speaking, riding a bike... procedural memory, memory for skills.
What is short term memory?
Limited Capacity Rehearsal maintains information in STS. Holds articulatory or phonological information.
Ebbinghaus's Discoveries
Logarithmic forgetting function Repetition improves memory Spacing effect
Taxonomy of human memory
Memory Declarative / Procedural Episodic or Semantic / Skills or Priming or Classical C Conditioning or Other
Do people remember unattended words (1999 experiment)
NO- in fact, from the recognition data, Ss have absolutely no memory of the unattended words *(inattentional amnesia)* no attending = no memory (inattentional amnesia)
evidence for engagement
Pulvinar nucleus is involved in preventing attention from being focused on an unwanted stimulus as well as directing attention to significant stimuli. In a PET study, LaBerge and Buchsbaum (1990) found increased activity in the pulvinar nucleus when subjects have to ignore a stimulus
How to test memory?
Recall Recognition You can recall it or you cannot recall it.
inattentional blindness or inattentional amnesia?
Rees, Russell, Frith and Driver (1999) provide answer using neuroimaging methods -showed subjects picture superimposed on a letter string. the letter string is either a word or a nonword, and subjects must pay attention to either the picture or the letter string and ignore the other stimulus
Word Length Effect
Short words are recalled better than long words. Faster speakers have higher working memory span.
Brooks (1968) Verbal Primary Task
Ss listen to sentences such as "A bird in the hand is not in the bush" and they are asked to indicate if each word is a noun. For this sentence, the answer would be "no, yes, no, no, yes..." - subjects answered either verbally or by pointing out their answers on a sheet
Brooks (1968) Spatial Primary Task
Ss view a block letter and then indicate, from the bottom left corner, if each corner is at the extreme top or bottom. For the letter "F", the answer would be "yes, yes, yes, no, no, no, no..." - again, subjects either answered verbally or by pointing out their answers on a sheet
Phonological Similarity Effect
Stimuli that sound similar are harder to recall than stimuli that sound dissimilar. The phonological similarity effect even happens with visual stimuli... but why? Articulatory Control Process
Partial Report Superiority
The partial report enabled Ss to report 3.04 letters per row, and 9.12 items for array, whereas whole report enabled 4.03 items total.
Slave Systems
The visuo-spatial sketchpad is the component for temporary storage and manipulation of spatial and visual information. The phonological loop is the component in which information is rehearsed and stored in a phonological (sound) form.
Baddeley and Hitch (1974)
Visual-spatial sketchpad Central executive Phonological Loop
study on whether unattended, or undetected, information get processed
Von Wright, Anderson, and Stenman (1975) 1) asked subjects to perform a dichotic listening-shadowing task 2) some words presented in the nonshadowed channel are associated with an electric shock.. 3) subjects report no awareness of these words associated with shock 4) but they show heightened galvanic skin response (GSR) to these words (on some level they know=guilty knowledge) 5) heightened GSR is usually associated with a heightened emotional state such as anger, fear, surprise, or sexual arousal
Working Memory
We have a newer conceptualization of short term memory -- working memory. Working memory emphasizes the role that attention plays in STM -- working with memory. Unlike the older idea of STM, the idea of working memory de- emphasizes the role of storage and emphasizes the role of attention and manipulation.
Irrelevant Speech Effect
Working memory performance is impaired when subjects hear irrelevant speech. Colle and Welsh (1976) asked subjects to remember visually presented consonants. • One group of Ss listened to irrelevant speech in the background. •Silent background for the other group.
is searchlight object or space based?
as the object rotates, left neglect patients kept focusing on the blue circle, even though now the blue circle is on their neglected side! (behrmann and tipper (1999)) *attention is both object and space based*
searchlight metaphor
attention researchers have likened our attentional control system to a searchlight beam that can illuminate either a small or large area
treisman's attenuation theory
attenuator: enhances detection of things consistent with what looking for/paying attention to and things similar to what you're paying attention to
change blindness
change blindness refers to an observer's remarkable inability to detect changes in scenes they are looking at apparently, there are large gaps in what we see. our perception of any visual scene is far from complete these results underscore the active nature of perception. we must expand some effort to see what we need to see. * must be paying attention when change happens * *must compare scenes and find difference in order to know there's a change*
Gray & Wedderburn (1960)
dichotic listening and shadowing - left ear: dear, 7, jane - right ear: 9, aunt, 6 subjects reported hearing dear, aunt, jane -prediction based on physical characteristics? NOT SUPPORTED - *should never cross over right and left ear*
Posner and Peterson (searchlight beam brain areas)
disengagement: unlock attention from a given visual stimulus shifting: move attention from one target stimulus to another engaging: lock attention onto new visual stimulus (and ignore distractors)
inattentional blindness = inattentional amnesia
don't perceive = don't remember
inattentional amnesia *does not =* inattentional blindness
don't remember *does not mean* you don't perceive
cocktail party problem (unattended vs. attended)
in dichotic listening task, Cherry asked subjects to shadow one channel. later, he asked subjects what was presented in the unattended channel. listeners seldom noticed when that message was spoken in a foreign language or even in reverse speech. subject could identify gender of questioner. people often have no memory of information presented in the unattended channel-- even if the info was presented 35 times (Moray, 1959)
visual attention
much more research on attention is done on visual attention compare with auditory stimulus, we have more control (flexibility) on the way visual stimuli are presented (presentation duration, etc.) and we have many more ways to vary a visual stimulus (color, shape, orientation, etc.)
task specific resources
needed for some tasks but no others. the nature of the task determines which resources are needed. two tasks will only interfere if they share the same type of resources. (e.g. if task A draws on spatial resources and task B draws on verbal resources, they should not interfere with each other)
Balint's syndrome
patients can focus on one object when it is presented alone, but they cannot focus their attention on more than one object even if the two objects are presented in close proximity
evidence for shifting
patients with damage to the midbrain have trouble making voluntary eye movements, which are essential for shifting attention from one target stimulus to another. patients with balint's syndrome may also have trouble with shifting attention
dichotic listening
put on headphones and hear one thing in left ear, another thing in the right ear
task general resources
relevant to all tasks, no matter what their nature. any two tasks will interfere with each other.
Rees et. al. overall results
results demonstrate true inattentional blindness for words and show that visual recognition wholly depends on attention even for highly familiar and meaningful stimuli at the center of gaze
neglect syndrome (left visual neglect)
right parietal damage ignore everything in left side of visual field - even ignore auditory from left side -may not respond to touch on left side *struggle with active and passive attention*
Moore and Egeth (1997)
showed subjects pictures that contained white and black dots with two horizontal lines around the center of the screen. participants job was to ignore the dots and judge which line was longer.
What is attention?
taking the possession of the mind, in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought. focalisation, concentration, and consciousness are it's essence.
early selection model
theory assumes that stimulus selection happens early in processing stream-- it occurs once the stimuli go into sensory stores due to the effectiveness of this stimulus selection filter, very little to no information presented via the unattended channel is processed but is this true? turns out the filter does not block out everything from the unattended channel for further processing
broadbents theory of selective attention
things you don't want to pay attention to=filtered out *only physical characteristics*
how to account for these findings (cocktail party)? attentional filtering
two stimuli presented simultaneously gain access to the sensory buffer in parallel. but a filter allows one input to pass through based on different physical characteristics of two stimuli. blocked stimuli is put on hold filter prevents overloading of the limited capacity attention system
subject shadowing
what they hear must be spoken out loud by subject
Rees, Russel, Frith and Driver(1999) results
when Ss attend to letter string, the brain activity associated with it is very different for words vs. nonwords, which is to be expected
Inattentional blindness or inattentional amnesia (1999 experiment)
when Ss attend to picture, the differences in brain activity between words and nonwords *disappear* no difference in brain activity when attending to pictures, but difference in brain activity when attending to letter-strings *STRONG EVIDENCE FOR NO ATTENTION=NO PERCEPTION*
Major findings for Phonological Loop
•The Phonological Similarity Effect •Irrelevant Speech Effect •Word Length Effect
