Iconic Memory

What is sensory memory

after stimuli disappears, one is able to retain the impressions of the sensory information

* complete, accurate, effortless but short-lasting (1/2 second)
* Vision→ iconic memory
* audition → echoic memory
* touch → haptic memory

What is Iconic memory

memory for visual stimuli after it disappears

* memory is complete- info is exact physical copy, brief (1/2 second), allowing stimulus to be accessed for a longer period of time.
* Sperling’s partial report technique measures the capacity and duration of this type of memory

What is Sperling’s Iconic Memory Experiements

Whole report condition: 3 by 4 matrix of letters is quickly flashed on screen, participants must immediately recall the letters.

* subjects could only report 4 or 5 letters (40%)
* Suggests that iconic memory is complete but short lasting bc after listing the 4-5 you can no longer see the matrix

Partial report condition: same matrix shown as whole report, after participants are cued to a specific row and have to recall just that row.

* subjects could recall 3-4 from each row which is 90%
* since cue is after the matrix is displayed, the participants are reading off of iconic memory
* provides evidence for the completeness of iconic memory as they can recall almost the entire row

testing for how duration of iconic memory: dely the cue and see how long it takes until the cue has no effect

* cue stops being useful just under 500ms (1/2 second)

What is partial report superiority

there is an advantage for partial report seen with partial report superiority until 500ms (ask for clarification on this.

What happens when you disrupt Iconic memory

once the iconic image is disrupted, the time one can see the image will automatically cause the decay of that memory instead of waiting for the full 500ms.

* 50ms display and 500 ms iconic = 550ms viewing time
* 50 ms display and 0 ms iconic = 50 ms viewing time

Masking

the presentation of a new display replacing the contents of the iconic memory

\
to reduce iconic memory:

* mask must be presented in the location as display
* mask must be within 300 ms od display offset (right after the display)
* Mask must contain visual pattern
* Interruption masking- mask interrupts image

What is the difference between interruption of masking and integration masking

both have the purpose to reduce the quality of the display

* Interruption masking: replacing the stimulus with the mask→ limits the duration of iconic memory
* Integration masking: superimposing the mask over the display→ making it harder to decipher the image but does not reduce iconic memory

What are the three main types of memory

1. sensory memory (iconic memory)
2. Short-term (working) memory
3. Long-term memory

What is short term memory

memories in which are currently receiving processing, attention and or conscious awareness

* can be held visually or phonologically
* getting and maintaining items in this memory requires attention
* decay of information occurs in

What is the capacity of short-term memory

Classically measured with digit span tasks → 7+/- 2 units but it can also be inferred from presence of the recency effect. The duration without rehearsal can be inferred form performance on the Brown-Peterson task

What does the Brown-peterson task on STM duration without rehearsal show

individuals have to do math for specified amount of time before recalling. THe longer time spent doing math, he less proportion they got correct.

* suggests that 18 seconds stops you from remembering 4 letters
* shows the input of rehearsal for working memory

WHat are the parts of Baddeley’s “working” Memory model

A. Phonological loop

B. Central Executive

C. Visuo-spatial sketch pad

D. Episodic buffer

E. LTM (knowledge) (memories)

Phonological loop (parts if working memory)

allows for the phonological rehearsal of items

* capacity is based off of phonological length (1.5s)
* evidence is that languages that have longer to say digits hold less
* difficulty of rehearsal increases when items sound similar
* can be impaired by producing and or listening to other speech
* central executive starts or stops tape loop each time

Visuo-spatial sketchpad (parts if working memory)

workplace for visual and spatial material- can store visual info encoded from verbal stimuli if phonological loop is taken by other verbal material

* visual WM capacity is 3 to 4 discrete items
* use of sketchpad can interfere with visual tasks or the reverse
* has a retention period of 900ms

Episodic Buffer (parts if working memory)

stores and integrates of information from the sketchpad and phonological loop and long-term memory

Central Executive (parts if working memory)

integration of info from phonological loop, visuo-spatial sketchpad and incoming info. controls coordinated behaviour and attention. does not store info. Allows one to work on several bits of interrelated info at one time. can also suppress irrelevant info. has capacity limitations which is why we cannot do multiple things at once.

Working Memory scores do what

predict ability to ignore irrelevant information and cognitive control

Conway cowan and Bunting WM predicting ability to ignore irrelevant material

Low WM associated with hearing own name in unattended ear in dichotic listening task

* 1/3 shadowing repetition remembering hearing own name were more likely to have a lower WM span as their WM was not properly managed as it cannot suppress irrelevant information to the task

Unsworth, schrock and engle WM and cognitive control

Low WM associated with longer antisaccades

* antisaccades require more cognitive energy. It took lower span people longer to do the harder task.
* Antisaccade: when something comes on the L and you are supposed look towards the right

Working memory

* associated with academic performance, intelligence test scores, attentional control


* the ability to work with information within the focus of attention is a critical cognitive skill
* WM is much more than a 7 +/- 2 short-term storage centre