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Sensory Memory Visual sensory memory - most of the information from the info processing model for sensory information is based on visual memory - Iconic memory is also knows an visual memory - Iconic memory: visual persistence: the apparent persistence of a visual stimulus beyond its physical duration o E.g. rapidly wobble a pencil between fingers and then doesn’t look like solid fingers o E.g. when watching a movie, it looks continuous  Continuous form of stimuli Sperling 1960 - How much info can the visual system take in, and how long does it hold it? - Get display of info and have to say that you saw - Whole report procedure: have to report everything you see - BLQT - FHSD - OGMZ - Participants remember about 4-5 digits out of 12 provided - This means o Memory diminishes over time, leading to a response limitation - Partial report procedure: a sample from the array - Participants recall about 3-4 digits out of 4 digits from cued row - Subjects saw a 3x4 grid of letters, presented very briefly - Results: Immediate- partial report more accurate than whole report o Delay: partial report accuracy drops quickly o After one second, accuracy is same as whole report o Sperling argued that decay is the mechanism by which information is lost from iconic memory Averbach and Coriell (1961) - Examined output interference effects using one letter responses - Used a visual cue after presentation of 2 rows of letters o Expt 1: a bar above the target position  When cue presented above target location, letter recall decreased with decay (like Sperling) o Expt 2: a ring around the target position  Cue presented around location, letter recall poor even with no decay  Cue function like a visual mask - Backward masking: when a later visual stimulus interferes with perception of an earlier one.

Decay and interference in iconic memory -

Combination of image decay over time and interference from later images Iconic memory is an initial and very fast step in perception Sperling thinks that decay is the mechanism which info is lost from in iconic memory

Pre-categorical -

has not been categorized in any meaningful way partial report advantage for precategorical features because they are “in” the location no partial report advantage for categorical factors bc they require more processing (not done in icon)

Ecological validity: does what your studying really matter in the world? - Real world perception - Visual images are continuous o Continuous flow of stimuli - Degree to which lab tasks resemble “real world” cognition o Called external validity - Saccadic suppression (rapid movement of eye between fixation points) o During saccades, we are functionally blind o Icons may help integrate information across saccades Properties of visual sensory memory - (Iconic memory) - Immediate store of visual information - Duration approx. .5-1.0 second - Capacity: large but hard to measure Auditory sensory memory (Echoic) -

Maintenance of a representation of auditory stimulus for a brief time Darwin, Turvey and Crowder 1972 o Like Sperling’s partial report technique for auditory stimuli o “three eared man” procedure  simultaneous presentation of 3 lists of items through headphones at different spatial locations  light indicates which set to recall o Replicated Sperling’s results  At short delays, partial > whole  Max number of items recalled was 5 and echo lasted for 4 seconds  Info held in echo much longer than icon

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Immediate store of auditory info Duration approx. 2-4 sec Capacity: large but hard to measure

What is the role of sensory memory? - integrating information across time and space - brief record permits selection for further processing (recall filter models) - provides coherence and stability despite constant receptor changes (e.g. eye movements) Components of memory 1) Central executive a. Allocation of attention/ resources b. Initiating retrieval and decision processes c. Integrating information d. Transfer info to LTM via rehearsal 2) Phonological loop a. Rehearsing of verbal info b. Phonological (auditory) processing 3) Visuo-Spatial Sketch pad a. Visual and spatial information i. E.g. route planning Information Processing Model - Attempts to describe how memory works - Preservation of sensory information for short periods - Raw, unprocessing, uncategorized format - Lots of things going on, but only some goes on to processing - Preservation of sensory info for short periods : 5 senses - Temporary storage of information - 2 types of sensory with most info/ research about visual and auditory o most comes from visual Short term Memory -

emphasis on storage static o e.g. remembering a phone number goes to LTM and coded and then back to STM refers to our capacity to keep limited amount of info in an active state other terms for STM o STM o Short term store or STS o Active memory

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o Working memory Miller argued that we can only maintain between 5-9 items in STM 7 +/- 2 but what is an item? Recall task: YMSTJEMQOU o Assess how much info you can keep in your head |BTW| JK| CVS| DNR| LOL o maybe groupings count as an item o groups are called chunks  number of items in a stimulus array determined  easier to remember things when we can group them to reduce memory load  Chunk: well-learned sequence/pattern of parts with a preexisting representation in LTM  Used to sort or organize info given limited capacity of STM 10 years to become an expert

Chunking in STM: Semantic Ericsson et al. 1980 - Student S.F. - 230 hours of training; digital span of 79 digits - used semantic chunking o e.g. 3492 remembered as 3 min 49.2 seconds - Ericson wanted to study supernemonics - Used existing frameworks to remember stuff - Used 3-4 digit chunks - STM improvement specific to digits Conclusion - not bigger STM, but specific encoding strategy - Individual differences in chunking ability - and resulting span capacity - experts do not have larger STM capacities o more effective chunking strategies - they have more effective chunking strategies - absolute differences in quantity Chase and Simon (1973) - chess experts vs. novices - master is good because he uses strategies for actual game positions - There is no advantage for master in random placements if he can’t chunk Conclusions: - STM can hold limited amount of info - Info determined by application of organizational schemes

- STM capacity is determined by chunking processes STM- Rapid loss of info - How to keep info in STM - Maintenance Rehearsal: repeating over and over again o Surface, does not work very well - Elaborative rehearsal o Deeper method, involves making connections o More likely to get elaborately rehearsed information into LTM - Maintenance rehearsal o Deeper method, involves making connections o More likely to get elaborately rehearsed information into LTM - Forgetting curve: drops off early o If test right away, then good o If can’t rehearse letters bc rehearsing numbers, how long will it take for you to forget? o Lose info from STM fairly rapidly?  Simply called forgetting When does forgetting happen? - Decay o Info fades away over time - Interference o Info is displayed or replaced or pushed out Decay and Interference Waugh & Noman 1965 - participants heard a list of 16 digits o last digit is called a probe o task: identify digit you heard immediately after the immediately previous instance of probe - varied.. o 1) number of items intervening between the probe and earlier mentioned instance of probe  interference more affects memory - 2) the rate at which they presented each digit during the task - decay because as more time passing, more decay -if loss is due to interference, the greater the number of intervening digits, the worse the performance - if loss is decay, the slower the presentation, the worse the performance - when number of different rates  better when numbers are presented quickly - but if there are more interferences, drastic change - so memory loss in STM is more due to interference Conclusion - info from STM is lost fairly rapidly

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rehearsal maintains information in STM info is lost largely as a function of interference o decay may play a lesser role

Storage in STM - what is representation like? - Recall sensory memory o Icon: stored visually o Echo: stored acoustically o Evidence that STM is stored both acoustically and semantically Acoustic Wicklegreen 1976 - Task: look at a set of letters and numbers and try to repeat them - Result: participants confused letters that sound alike - Occurred even though participants had seen letters and numbers instead of hearing them - If we do encode info acoustically, do deaf people lack STM functioning o Don’t o Acoustic isn’t the only form of encouding o So perhaps semantic Wickens 1972 - participants heard a list of objects - then heard 3 digits - asked to count backwards by 3s - recall list of objects o as people get more lists of fruit words, might say something from previous list - Proactive interference o Info learned earlier interferes with info you are trying to learn o Semantic similarity led to proactive interference  But if hear different semantic category, like clothes, will not have interference  If semantic category was changed during experiment, this leads to release from proactive intereference  Changed category to semantically dissimilar items improved performance Conclusion - info in STM is encoded acoustically and also semantically...