1. Memory Recognition cont.
PSY 368 Human Memory
Memory
Recognition cont.

2. Experiment 2 Signal Detection (Download details from BB)
Like last time, find 3 participants
You’ll need index cards for the words (write one word per card)
Read instructions to participants, the IV is manipulated with different instructions for each condition, so make sure that you read the correct instructions. You’ll need to print out 3 copies of the “memory test” (1 for each participant)
Fill out the datasheet and bring it to class on Monday (March 5th, date in assignment is old Fall date). I will compile data for whole class and bring it on Wednesday March 7th
Reports will be due the Wednesday after Spring Break (March 21st),

3. Experiment 1 results Overall (N = 18) General report comments
Immediate 7.6 items
Delayed 6.0
Distraction 3.5
General report comments
Don’t identify your participants
Stick to APA style as much as you can
Include your datasheet
Primacy effect in all three conditions
Recency effect strongest in immediate condition

4. How does Recognition work?
Two classes of theories
Single process theories - retrieval is one process regardless of task
Tagging Model (Yntema & Trask, 1963)
Strength Theory (Wickelgren & Norman, 1966)
Dual process theories - two processes needed for retrieval - can be task dependent
Generate-recognize model (G-R)
e.g., Anderson & Bower (1972)’s HAM
Remember/Know processes model (R/K)
Processes differ by theory for dual process theory
Several versions of each type of theory

5. Dual-process theories
Generate-recognize model (G-R)
Recall is made up of two processes
First, generate a set of plausible candidates for recall (Generation stage)
Second, confirm whether each word is worthy of being recalled (Recognition stage – not the same as the recognition test)
Recognition is made up of only one process
Because the experimenter provides a candidate, recognition does not need the generation stage
Generation of possible item, recognition of studied items
This model can predict interactions of effects for recall and recog:
Incidental learning means fewer inter-item associations - hurts generation
- better encoding of individual item info - helps recognition - Intentional opposite
Low frequency items also result in fewer inter-item associations
- hurts generation and lowers recall - high frequency items encoded better

6. Dual-process theories
Remember versus Know Process Model
(Tulving, 1985; Gardiner, 1988)
Relatively recent change in recognition methodology
When you recognize something, do you:
Specifically remember (linked to Episodic memory)
Conscious recollection of the information’s occurrence at study
Just somehow know (linked to Semantic memory)
Knowing that it was on the list, but not having the conscious recollection, just a “feeling of knowing”

7. Dual-process theories
Remember versus Know Process Model
Tulving (1985)
Present subjects with 27 category-member pairs (FRUIT– pear)
Recall tests:
Free recall test
Cued recall test (category) FRUIT
Cued recall test (category + first letter of target) FRUIT- p
Results
The proportion of remember judgments decreased over the three kinds of tests
Prob(remember)
0.88
0.75
0.48

8. Dual-process theories
Remember versus Know Process Model
Gardiner et al (1990, 1991, 1993)
Remember/Know processes
Make R/K judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of presentation
Used to further investigate two possible processes involved in recognition
Recognition - Old/New response + Remember/Know judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of
Presentation
R/K responses for correct “Old” items have been shown to differ for the
following effects:
Typically studied pics are better remembered than words (picture superiority
effect) R: Pics > words and K: words > pics
Generate similar or related word
Hot - ?
Cat - ?
vs. reading hot-cold and cat-dog
R/K differ by:
Picture superiority effect
R: P > W
K: W > P
Word frequency effect
R: L > H
K: H = L
Generation effect
R: G > R
K: R = G

9. Remember Versus Know Remember versus Know Process Model
Gardiner et al (1990, 1991, 1993) gives an explanation:
Remember judgments are influenced by conceptual and attentional factors
Know judgments are based on a procedural memory system
This is similar to a distinction between explicit and implicit memory (more on this next week)

10. Techniques used to distinguish dual processes
Signal Detection Theory
A technique for separating discrimination (“true” detection) from response bias
Process Dissociation (next week)
A technique for separating intentional (effortful) retrieval processes from incidental (automatic) retrieval processes
May want to go back and review pages

11. Signal Detection Theory
A model for explaining recognition memory
Based on auditory perception experiments:
Typical Task:
Ask participants to detect a faint tone (signal) presented against a background of noise
The tone’s loudness against the background noise is manipulated
Volume
Background Noise
Used to further investigate two possible processes involved in recognition
Recognition - Old/New response + Remember/Know judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of
Presentation
R/K responses for correct “Old” items have been shown to differ for the
following effects:
Typically studied pics are better remembered than words (picture superiority
effect) R: Pics > words and K: words > pics
Generate similar or related word
Hot - ?
Cat - ?
vs. reading hot-cold and cat-dog
Hard-to-Detect Signal
Easy-to-Detect Signal

12. Signal Detection Theory
Brief History
In World War II radar waves were used to detect enemy aircraft.
The soldiers had to determine if the little spots of light are enemies, or simple noise (I.e. birds).
There was no clearly defined criteria for making these kinds of decisions.
SIGNAL: Are the spots on the screen enemies?
Consequences:
If an enemy went undetected, people could be killed.
If noise was interpreted as an enemy, time and money would be lost and people would be put in harm’s way
yes no
DECISION:
Should you scramble the jets?
Used to further investigate two possible processes involved in recognition
Recognition - Old/New response + Remember/Know judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of
Presentation
R/K responses for correct “Old” items have been shown to differ for the
following effects:
Typically studied pics are better remembered than words (picture superiority
effect) R: Pics > words and K: words > pics
Generate similar or related word
Hot - ?
Cat - ?
vs. reading hot-cold and cat-dog
Hit
False alarm
Miss
Correct reject
yes no

13. Signal Detection Theory
Response bias is based on a participant’s preference for a particular outcome.
Preferences are based on costs & rewards
For example,
People will die because I failed to detect enemy, that is a very high cost.
If congress yells at me for spending money, that is not a very high cost.
SIGNAL: Are the spots on the screen enemies?
yes no
DECISION:
Should you scramble the jets?
Used to further investigate two possible processes involved in recognition
Recognition - Old/New response + Remember/Know judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of
Presentation
R/K responses for correct “Old” items have been shown to differ for the
following effects:
Typically studied pics are better remembered than words (picture superiority
effect) R: Pics > words and K: words > pics
Generate similar or related word
Hot - ?
Cat - ?
vs. reading hot-cold and cat-dog
Hit
False alarm
Miss
Correct reject
yes no

14. Signal Detection Theory
Criterion level (C or β) is set based on outcome preferences.
Criterion level: The intensity at which a signal will be reported as being present (Not the intensity at which it is perceived).
High Criterion: less hits but also less false alarms
Low criterion: more hits but also more false alarms
SIGNAL: Are the spots on the screen enemies?
yes no
DECISION:
Should you scramble the jets?
Used to further investigate two possible processes involved in recognition
Recognition - Old/New response + Remember/Know judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of
Presentation
R/K responses for correct “Old” items have been shown to differ for the
following effects:
Typically studied pics are better remembered than words (picture superiority
effect) R: Pics > words and K: words > pics
Generate similar or related word
Hot - ?
Cat - ?
vs. reading hot-cold and cat-dog
Hit
False alarm
Miss
Correct reject
yes no

15. Signal Detection Theory
Criterion level (C or β) is set based on outcome preferences.
Criterion level: The intensity at which a signal will be reported as being present (Not the intensity at which it is perceived).
High Criterion: less hits but also less false alarms
Low criterion: more hits but also more false alarms
- Criterion +
No alert
Call for
jets
stimulus intensity
probability
Noise
Signal
(enemy)
Used to further investigate two possible processes involved in recognition
Recognition - Old/New response + Remember/Know judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of
Presentation
R/K responses for correct “Old” items have been shown to differ for the
following effects:
Typically studied pics are better remembered than words (picture superiority
effect) R: Pics > words and K: words > pics
Generate similar or related word
Hot - ?
Cat - ?
vs. reading hot-cold and cat-dog

16. Signal Detection Theory
d’ (“Dee-prime”) = Discriminability
The difference between the means
Low d’
stimulus intensity
probability
Noise
Signal
(enemy)
If d’ is low, then this means there is low discriminability.
The noise and stimulus are highly overlapping.
d’ = 0: pure chance
If d’ is high, then this means there is high discriminability.
d’ = 1: moderate performance
d’ = 4.65: “optimal” (corresponds to hit rate=0.99, false alarm rate=0.01)
high d’
Used to further investigate two possible processes involved in recognition
Recognition - Old/New response + Remember/Know judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of
Presentation
R/K responses for correct “Old” items have been shown to differ for the
following effects:
Typically studied pics are better remembered than words (picture superiority
effect) R: Pics > words and K: words > pics
Generate similar or related word
Hot - ?
Cat - ?
vs. reading hot-cold and cat-dog
stimulus intensity
probability
Noise
Signal
(enemy)

17. Signal Detection Theory
Recognition accuracy depends on:
Whether a signal (noise/target memory) was actually presented
The participant’s response
Thus, there are four possible outcomes:
Hits
Correctly reporting the presence of the signal
Correct Rejections
Correctly reporting the absence of the signal
False Alarms
Incorrectly reporting presence of the signal when it did not occur
Misses
Failing to report the presence of the signal when it occurred
CORRECT
Used to further investigate two possible processes involved in recognition
Recognition - Old/New response + Remember/Know judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of
Presentation
R/K responses for correct “Old” items have been shown to differ for the
following effects:
Typically studied pics are better remembered than words (picture superiority
effect) R: Pics > words and K: words > pics
Generate similar or related word
Hot - ?
Cat - ?
vs. reading hot-cold and cat-dog
INCORRECT

18. Signal Detection Theory
Assumptions:
Memory traces have strength values (i.e. activation levels)
Activation levels dictate how “familiar” a stimulus feels
Traces vary in terms of their familiarity, based on:
Attention paid to the stimulus during encoding
The number of repetitions
Familiarity values for “old” and “new” items are each normally distributed
On average, “new” items are less familiar than “old” items
However, some distractors are quite familiar because they appear often in other contexts or are similar to “old” items
Thus, there can be overlap between the distributions
Items that surpass a threshold (i.e. response criterion) of familiarity are judged “old”

19. Signal Detection Theory
Everything more familiar than (to the right of) the response criterion (beta or β) will be judged “old”
A centrally placed β is unbiased
Everything less familiar (i.e. to the left of β) will be judged “new.”
Hits (in green)
Misses (in red)
Above, the same distribution with the focus on the lure distribution to highlight:
Correct rejections (in green)
False alarms (in red)
D prime (d’) represents:
The distance between the distributions
The participant’s ability to discriminate the two distributions

20. Signal Detection Theory
A more liberal guesser will:
Have a response criterion shifted to the left
Accept more targets as “old” (i.e. hits)
Accept more lures as “old” (i.e. false alarms)
A more conservative guesser will:
Shift β to the right
Have fewer hits
Have fewer false alarms
Thus, the overlap in the distribution leads to:
Trade offs between hits and false alarms
Depends on the placement of the response criterion

21. Signal Detection Theory
Calculating d’ and C (or β)
Discriminability (d’):
Step 1) Look up the z-score for the average Hit and False Alarm rates.
Step 2) Apply the formula d’ = zHIT – zFA, where zFA is the z-score for FAs and zHIT is the z-score for Hits.
Criteria C (or β):
Take the negative of the average of zHIT and zFA. This is the criterion value C.
Remember that positive C values indicate a conservative response bias, while negative C values indicate a liberal response bias.
We will go over this in class again next week when we have our data for Experiment 2

22. Face Recognition
Special recognition ability

23. Face Recognition Evidence for special ability: Prosopagnosia
The inability to recognize previously seen faces, with relative sparing of other perceptual, cognitive and memory functions.
Intact ability to identify people using nonfacial features (voice)
Due to brain injury (typically to the right temporal lobe)
Broad Subtypes:
1. Apperceptive - failure to generate a sufficiently accurate percept to allow a successful match to stores of previously seen faces.
2. Associative - accurate percept, but failure to match because of loss of facial memory stores or disconnection from them.
Prosopagnosia - inability to recognize faces - due to brain injury - other
abilities left intact

24. Face Recognition Evidence for special ability: (2) Newborn preferences
Studies done by Fantz (1961, 1963) - had kids look at three kinds of figures
Morton and Johnson (1991) report that new-born babies will preferentially view faces
Prosopagnosia - inability to recognize faces - due to brain injury - other
abilities left intact
Studies done by Fantz (1961, 1963) - had kids look at three kinds of figures
Newborns prefer to look at human faces than other objects.

25. Face Recognition Evidence for special ability:
(3) Face inversion effect
Yin (1969) found that whilst people are generally better at recognising upright faces than they are other objects. They are worse for inverted faces than they are for other inverted objects.
Inverted faces are much harder to identify as compared with other objects that are inverted
This suggests that the processing underlying normal face recognition is different from those underlying object recognition.

26. The ‘Thatcher Illusion’
(Thomson, 1980)

27. The ‘Thatcher Illusion’
(Thomson, 1980)

28. Why does the ‘Thatcher illusion’ occur?
Bartlett and Searcy (1993) conducted experiments to measure face ‘grotesqueness’.
Their results supported the “configural processing hypothesis”
i.e. We have a difficulty in understanding the configuration of features when faces are inverted.
We aren’t aware of the odd configuration of elements within the inverted Thatcher image.

29. Find the human face in the display as fast as you can. Ready?
Face Recognition
Evidence for special ability:
(4) Pop-out effect for faces (Herschler & Hochstein, 2005)
Find the human face in the display as fast as you can. Ready?
Inverted faces are much harder to identify as compared with other objects that are inverted

30. Find the human face in the display as fast as you can. Ready?
Face Recognition
Find the human face in the display as fast as you can. Ready?
Inverted faces are much harder to identify as compared with other objects that are inverted

31. Now find the animal face. Ready?
Face Recognition
Evidence for special ability:
(4) Pop-out effect for faces (Herschler & Hochstein, 2005)
Now find the animal face. Ready?
Inverted faces are much harder to identify as compared with other objects that are inverted

32. Face Recognition
Inverted faces are much harder to identify as compared with other objects that are inverted

33. Summary Recognition is an explicit memory test.
Single- and dual-process theories of recognition
Single-process can’t account for differences across recall and recognition
G-R theory can’t account for items that are recalled, but not recognized
Face recognition seems to be a special ability
Inverted faces are much harder to identify as compared with other objects that are inverted

34. The Mirror Effect
Observed when “The type of stimulus that is accurately recognized as old when old is also accurately recognized as new when new. The type that is poorly recognized as old when old is also poorly recognized as new when new.” (Glanzer & Adams, 1985, p.8)
Pervasive in recognition tests
High/low word frequency and hit/false alarm rates, presentation rate, age of subject, ...

35. The Mirror Effect - Example
The Mirror Effect and the Word Frequency Effect
Word Frequency
High
Low
Hits
27.84
31.00
False Alarms
10.20
7.63
Source: Human Memory, p. 214

36. The Mirror Effect
Significance: It eliminates all theories of recognition based on a unidimensional conception of strength or familiarity (single process models)
May be able to be explained by dual process models
Explanations for the mirror effect are still being formed

37. Dual-process theories
Dissociating Recollection and Familiarity
Process Dissociation Procedure (Jacoby, 1991)
Task:
Participants study two sets of items in different contexts
Two different recognition tests follow:
Inclusion Condition:
Say “yes” if they recognize an item from either context
Correct recognition = Recollection + Familiarity
Exclusion Condition:
Say “yes” only if they recognize an item from one of the two contexts
Familiarity = False alarms in exclusion condition
Recollection = Inclusion’s correct recognition minus Familiarity
Used to further investigate two possible processes involved in recognition
Recognition - Old/New response + Remember/Know judgment for “Old” items
Remember = consciously recollect details of the item’s presentation
Know = sure an item was presented, but can’t recall any of the details of
Presentation
R/K responses for correct “Old” items have been shown to differ for the
following effects:
Typically studied pics are better remembered than words (picture superiority
effect) R: Pics > words and K: words > pics
Generate similar or related word
Hot - ?
Cat - ?
vs. reading hot-cold and cat-dog