1. Sensory Memory, Short-Term Memory & Working Memory
Psychology 355: Cognitive Psychology Instructor: John Miyamoto 04/17/2018: Lecture 04-2
Note: This Powerpoint presentation may contain macros that I wrote to help me create the slides. The macros aren’t needed to view the slides. You can disable or delete the macros without any change to the presentation.

2. To Be Discussed Later
Memory Systems
UW: Psych 355, Miyamoto, Spr '18

3. Overview of Memory Systems:
This lecture
Sensory Memory Short-Term Memory / Working Memory (STM / WM) Long-Term Memory (LTM) What function do these memory systems serve?
Later WM
Multiple Components
LTM
Multiple Components
Psych 355, Miyamoto, Spr '18
What Are Memory Systems?

4. What Are Memory Systems?
Memory systems retain perceptions, images, motor patterns, experiences, ideas, thoughts, and intentions that were present at one time but are no longer present.
Major Functions of Memory Systems
Store information over a period of time (seconds; minutes; hours; years)
Pass information between different memory systems
Encode information (put information into a long-term storage)
Retrieve memories or previous learning based on relevance or usefulness in current processing.
Especially important: Retrieval of information that is relevant to a current activity.
Manipulate information in working memory
UW Psych 355, Miyamoto, Spr '18
Modal Model of Memory

5. The Modal Memory Model (Atkinson & Shiffrin, 1968)
Goldstein Figure 5.2
Sensory Memory
Short-Term Memory
Long-Term Memory
Input
Control Processes, e.g., rehearsal
Output: Speech & Actions
The Modal Model of Memory (Atkinson & Shiffrin, 1968)
Sensory Memory – brief storage of current perceptual inputs.
STM – short-term storage of current mental activity
STM or Working Memory (WM) has multiple components
LTM – long-term storage of experiences, thoughts, facts
LTM also has multiple components
Psych 355, Miyamoto, Spr '18
What Happens When Rachel Looks Up a Phone Number

6. What happens as Rachel looks up a phone number?
(a) She looks at the page in the phone book Perceptual information enters sensory memory.
(b) She pays attention to the relevant phone number. The number is stored in short-term memory (STM).
(c) She dials the phone number while main taining the number in STM (rehearsal).
Example Continued
UW Psych 355, Miyamoto, Spr '18

7. What happens as Rachel looks up a phone number?
(d) She memorizes the phone number (stores the number in long term memory or LTM). This process is called encoding.
(e) Days later, she retrieves the number from LTM.
Return to the Modal Memory Model
UW Psych 355, Miyamoto, Spr '18

8. The Modal Memory Model (Atkinson & Shiffrin, 1968)
Goldstein Figure 5.2
Sensory Memory
Short-Term Memory
Long-Term Memory
Input
Control Processes, e.g., rehearsal
Output: Speech & Actions
The Modal Model of Memory (Atkinson & Shiffrin, 1968)
Sensory Memory – brief storage of current perceptual inputs.
STM – short-term storage of current mental activity
STM or Working Memory (WM) has multiple components
LTM – long-term storage of experiences, thoughts, facts
LTM also has multiple components
Psych 355, Miyamoto, Spr '18
Distinction Between STM and LTM

9. Distinction Between STM & LTM
Standard STM example: Remember the following words:
We will wait, perhaps, 15 seconds. Then I’ll ask you to tell me the words that you read in the order that they were written.
Another STM example: You know where you are right now and what you are doing there. You are actively processing this information (along with other thoughts).
LTM refers to a variety of memory processes that allow retrieval of memories that are not currently preserved in STM.
hand, chair, reed, bottle
UW: Psych 355, Miyamoto, Spr '18
Illustration of LTM vs STM Distinction from Goldstein Textbook

10. Figure 6.1: Example of the STM/LTM Distinction
List of Functions That Are Included in LTM
UW: Psych 355, Miyamoto, Spr '18

11. LTM Includes .....
Important information about the self and events in the world, but also, ...
Trivial information about what has happened in the recent past,
e.g., what was the picture at the beginning of the lecture), and also, ....
“Semantic” knowledge, e.g., what is an apple, a pencil; which is bigger, a mouse or a moose; etc.
How to do things: Tie your shoes, drive a car, dial a phone number, cook a meal, ....
Learned associations that are not explicit, e.g., the atmosphere of a dentist’s office makes you feel apprehensive.
UW: Psych 355, Miyamoto, Spr '18
Diagram of Modal Memory Model – Next Topic = Sensory Memory

12. The Modal Memory Model (Atkinson & Shiffrin, 1968)
Sensory Memory
Short-Term Memory
Long-Term Memory
Input
Control Processes, e.g., rehearsal
Output: Speech & Actions
Next
Sensory Memory – brief storage of current perceptual inputs.
STM – short-term storage of current mental activity
STM or Working Memory (WM) has multiple components
LTM – long-term storage of experiences, thoughts, facts
LTM also has multiple components
Definition of Sensory Memory
UW Psych 355, Miyamoto, Spr '18

13. Sensory Memory Example: Sparkler trail or flash image in a dark room.
Sensory memory is the retention of the effects of sensory stimulation. Very brief – less then 1 second.
Sensory memory is partly due to processes that are close to level of the receptors, but it has a major component that is central.
"Central" means at the level of the cortex, i.e., at the level of the visual cortex for visual stimuli; at the level of the auditory cortex for auditory stimuli, etc.
What are the capacity limits for visual sensory memory? How much information is stored? How long can it be stored?
UW Psych 355, Miyamoto, Spr '18
Diagram: Where Is the Capacity Limit in the Memory System?

14. Evidence for a Capacity Limit on Sensory or Short-Term Memory
Suppose a letter array is flashed on the screen to the right.
Can you name all of the letters in a specific row, e.g., in Row 3?
E R U P W I N Q M X T V Y S O K
Psych 355, Miyamoto, Spr '18
Continue with Slide with Example of Pre-Cueing

15. Evidence for a Capacity Limit on Sensory or Short-Term Memory
Suppose a letter array is flashed on the screen to the right.
Can you name all of the letters in a specific row, e.g., in Row 3?
The task is easy if I tell you the row to remember before I flash the letter array. (See letter array to the right.)
Pay attention to Row 2.
Answer: P E C Z
E R U P W I N Q M X T V Y S O K
O A W N P E C Z H X M U V F B I
O A W N P E C Z H X M U V F B I
Psych 355, Miyamoto, Spr '18
Same Problem is Hard If You Must Remember All 16 Letters

16. Evidence for a Capacity Limit on Sensory or Short-Term Memory
Suppose a letter array is flashed on the screen to the right.
Can you name all 16 letters in the array?
The task is hard if I ask you to remember all 16 letters in the letter array. (See letter array to the right.)
What were the 16 letters in the array?
# # # # # # # # # # # # # # # #
U R V X Y Z Q M I C D W L T J N
U R V X Y Z Q M I C D W L T J N
Is the Capacity Limit on Sensory Memory or STM?
Psych 355, Miyamoto, Spr '18

17. Controversy: Is the capacity limit a limit on sensory memory, or short-term memory?
Transfer too slow?
Limit here?
Limit here?
Sensory Memory
Short-Term Memory
Long-Term Memory
Input
We have evidence that a capacity limit exists: You can accurately report a pre-selected 4 letters from a 12 letter array, but you can't accurately report all 12 letters.
Is there a limit on the capacity of sensory memory?
Sperling's Partial Report Paradigm
UW Psych 355, Miyamoto, Spr '18

18. Sperling’s Partial Report Procedure (Paradigm)
Digression on Terminology: An "experimental paradigm" is a type of experiment. Often there will be many experiments that all use the same paradigm.
Purpose of Sperling's partial report paradigm: To determine what are the limits on the capacity of sensory memory.
To save lecture time, I may cut short the following explanation of Sperling's partial report paradigm. (To discuss, or not to discuss?)
Students will be responsible for knowing its purpose and its conclusions.
Notice use of timing of stimulus to explore the way the information is processed.
Sperling’s partial report paradigm is important for perceptual psychology. Not so important for higher cognitive processes.
UW Psych 355, Miyamoto, Spr '18
Sperling's Partial Report Paradigm

19. Measuring the Capacity & Duration of Sensory Memory
Sperling's Partial Report Paradigm
3 x 4 array of letters displayed for 50 ms (0.05 seconds)
The image of the array persists in sensory memory even after it is physically gone.
 How much information is stored in sensory memory?
 How long does the information last in sensory memory?
Psych 355,, Miyamoto, Spr '18
More-Or-Less Unlimited Capacity of Sensory Memory

20. What is the Capacity of Sensory Memory?
 How much information is stored in sensory memory? Capacity is very large, but there is no known way to quantify how large. Remainder of this discussion addresses the question:  How long does the information last in sensory memory?
Psych 355,, Miyamoto, Spr '18
Sperling's Paradigm: Whole Report Condition

21. Whole Report Condition: No Cues Are Given
3 x 4 array of letters displayed for 50 ms (0.05 seconds)
Subject must try to report all 12 letters in the array.
Result:
4.5 letters correctly reported out of 12 possible (average result)
Psych 355,, Miyamoto, Spr '18
Partial Report Condition: 0.0 Delay in Tone Cue

22. Partial Report Condition: 0.0 Sec. Delay in Tone Cue
3 x 4 array of letters displayed for 50 ms (0.05 seconds)
Simultaneous with disappearance of array, subject hears a tone
High tone  Report Row 1 Medium tone  Report Row Low tone  Report Row 3
Result:
3.3 letters correctly reported out of 4 possible (average result)
Psych 355,, Miyamoto, Spr '18
Partial Report Condition: 1.0 Delay in Tone Cue

23. Condition 3: Partial Report, 1 Sec. Delay in Tone Cue
3 x 4 array of letters displayed for 50 ms (0.05 seconds)
1 second after disappearance of array, subject hears a tone
High tone  Report Row 1 Medium tone  Report Row Low tone  Report Row 3
Result:
1.0 letters correctly reported out of 4 possible (average result)
Psych 355,, Miyamoto, Spr '18
Summary of Results for Duration of Sensory Memory

24. Summary of Results for Duration of Sensory Memory
Amount of information in sensory memory decreases over time.
By a little more than 1.0 seconds it is gone.
(How do we know that the capacity of sensory memory is very large? With 0 delay, you can cue any position in the array and get accurate memory of what is at that position.)
Psych 355,, Miyamoto, Spr '18
Diagram of Standard Model: Conclusion re Capacity of Sensory Memory

25. Conclusion of Partial Report Experiment
Very large, possibly unlimited capacity.
Information decays to 0 in about 1 second.
Control Processes
Input
Sensory Memory
Short-Term Memory
Long-Term Memory
Output: Speech/Actions
UW Psych 355, Miyamoto, Spr '18
What Is Meant By Capacity Limits on Memory?

26. What Is Meant by Limits on Memory Capacity?
Limit on memory capacity refers to a limit on the amount of information that can be held in memory.
Not the amount of information that can be input to memory (encoding), and not the amount of information that can be retrieved from memory (retrieval).
Sensory memory – very large, approximately unlimited Short-Term memory – ? Long-Term memory – very large, approximately unlimited
Next: Introduction to Short-Term Memory & Working Memory
UW Psych 355, Miyamoto, Spr '18
Overview of Short-Term Memory & Working Memory