Lecture 6 Oct. 21 Cognitive Psychology
Objective of today’s lectures is to move from the original concept of STS to the concept of
Working Memory. We begin by revisiting the evidence that we used to develop the original
concept of STS (remembering a list of words) and show that the evidence is not unequivocal.
• STS evidence revisited
A. Amnesics can learn: They cannot remember things, but they can learn. It is shown
that Korsakov patients who do a puzzle over and over again get better at the puzzle,
even though they don’t remember doing it.
B. Serial Position Curve
i. Bjork and Whitten Paired associate task: Shown a list of pairs of words.
There is a 20 second delay at the end of the task with a distraction. They are
then cued with the first word, and asked to recall the paired word. Found
strong recency effects even with distraction, suggests that recency effects
may reflect more than just retrieval from STS.
C. STS Code not just AVL
i. Kroll: Had people do a shadowing task, and were given a test letter during the
task. In one condition people saw the letter, in another they heard it. The task
was to remember the letter while shadowing, for about 10-15 seconds. For a
short interval (1-3seconds) people did well remembering the letter visually or
audibly. For a long interval, visual retention was stronger.
ii. Shepard and Metzler: Gave people 3D objects on a paper, and had them
rotate the objects mentally to see if it matched another object. It was found
that people could complete the task, and could complete it faster the less the
object had to be rotated. This shows that visual codes are used to temporarily
store and manipulate information.
iii. Shulman: Gave participants lists of 10 words. They were then given another
word, and asked if it was in the list. Similar words, like boat when ship was in
the list, people were more likely to make a mistake and say they saw a word
• Working Memory (WM)
i. STS: initially viewed as a storage system. However, the same system seems
to be important for active processing and manipulation of info. This means we
needed a new concept to extend STS. Thus he came up with… ii. WM: Active system for temporary store and manipulation of info.
iii. Components of the WM:
Plan actions, integrate information
Transfer of info to/from LTS
- rehearsal, recoding
Phonological Loop Visuo-spatial Sketchpad
Recycle info for immediate recall Visual imagery tasks