Memory Errors Flashcards
1
Q
A classification of memory errors (schacter, 1999, 2021)
A
- Transience: Forgetting of memories (iconic memory, echoic memory, forgetting from working memory, forgetting from long-term memory)
- Absent-mindedness: Memory errors due to attentional failures at encoding or retrieval (not learned at all or at a level where they can be recalled).
- Blocking: Inability to retrieve information although it has been encoded deep (Tip of the tongue feeling- e.g. know a specific name but cannot remember it until later on)
- Bias: Memory distortion of previous experiences due to influences of present knowledge, beliefs, and feelings.
- Misattribution: Accurate memories assigned to the wrong source (when we remember something but might not be entirely accurate e.g. who said it)
- Suggestibility: Memories which incorporate inaccurate information from an external source e.g. something you have read
- Persistence: Inability to avoid unwanted, intrusive memories of traumatic or arousing events.
These are the 7 types of memory errors
2
Q
transcience- incidental forgetting
A
- How we commonly think about forgetting- a typical idea of what it looks like e.g. when we lose our keys (forget where we put them)
- Tend to forget a lot of information as soon as we learn it- the other things we remember we remember for a long time
- Rate of forgetting is non-linear with maximum loss shortly after learning and little additional loss of information at longer delays.
- Forgetting curves for different types of information and different degrees of learning are comparable.
- Forgetting has been linked to interference between current and past information.
- Proactive interference: Older memories affect newer memories.
Retroactive interference: New memories affect past memories.
3
Q
ebbinghaus curve
A
- Ebbinghaus curve is generally accepted as how we forget and how fast it happens
- 2 theories of why we forget:
- Decay: neural basis of these memories fade away. This has to be true as they are stord on neurons and neurons die. So we will lose memories as their storage does not stand the test of time. Very difficult to investigate decay in humans- cannot put them in a scenario where there is no additional distractions
Interference: lots of information we encounter and process somehow affects learning that has occurred before (proactive and retroactive interference)
- Decay: neural basis of these memories fade away. This has to be true as they are stord on neurons and neurons die. So we will lose memories as their storage does not stand the test of time. Very difficult to investigate decay in humans- cannot put them in a scenario where there is no additional distractions
4
Q
suppression of memories
A
- Do we choose which memories to retain and which to forget?
- Basic tenant of psychoanalysis- we experience pathological conditions so we behaviour in certain ways due to trauma from our past that we try to suppress
- The idea of painful memories and how we try to avoid and suppress these is a basic idea that comes from Freud
- One of the basic elements of Freudian theory is the notion of “repression” or “suppression”.
- Undesirable or painful feelings, images and thoughts are pushed out of memory to stop them interfering with our everyday lives.
- According to Freud this banishment of unwanted memories can be either a conscious or an unconscious process.
- Sometimes repression is used for unconscious and suppression for conscious forgetting
Can we find experimental evidence of memory suppression?
- Sometimes repression is used for unconscious and suppression for conscious forgetting
5
Q
directed forgetting- the item method- Anderson & Hanslmayr, 2014
A
- In the item-method, after each item is presented at encoding, participants are asked to either remember or forget the preceding item
- At tests they are asked to retrieve all items and participants retrieve more remember than forget items
- Not because they are trying to comply with the forget cue but because they do not have memory of these items and their recognition is poor
- The effect is found for both pictures and words and in both recall and recognition tests suggesting deficits at encoding than difficulties at retrieval
- Perhaps, the memory was not created at the first place
- What is behind the item-method forgetting?
- The Selective Rehearsal hypothesis suggests that people restrict elaborative processing of the Forget items
- There is more cognitive effort in Remember than Forget trials
- They only do the additional elaboration for items that receive the remember cue
- This makes sense intuitively as you are told not to remember certain words- prediction that we have from this is that there is more cognitive effort in remember than forget trials
- The Encoding Suppression hypothesis suggests that forgetting is an active process
- There is more cognitive effort in Forget than Remember trials
- Try t inhibit the formation in memory- more cognitive effort
- There is evidence that reaction times to a secondary task is slower after Forget than Remember items (Fawcett & Taylor, 2008)
- One possibility is that there are fewer resources available in Forget trials because Forget trials involve additional processing
- Suggests much greater processing happen in forget trials- more in line with the encoding suppression hypothesis
Active memory suppression mechanism
6
Q
directed forgetting- the list method Anderson & Hanslmayr, 2014
A
- Another way to induce forgetting is to interfere with retrieval processes
- In the list-method, two lists are presented. At the end of one list and without expecting it, participants are asked to forget the preceding items.
- At test, they are asked to retrieve all items and participants retrieve more from the remember than the forget list.
- The effect is found only in recall (recognition memory is not impaired) suggesting the deficit affects locating the memory (i.e. retrieval).
- What is behind the list-method forgetting?
- The Retrieval Inhibition hypothesis assumes that the forget cue starts an active inhibition control process that reduces recall of List 1 items
- The Context Change hypothesis suggests that a forget cue introduces a new mental learning context for List 2 words. List 1 words do no longer match the new context and recall is impaired.
- Results similar to list method when participants were asked (instead of receiving a forget cue) to imagine what their life would be like if they were invisible.
Evidence shows that list method forgetting but not context change effects are present at long delays supporting the Retrieval Inhibition account (Abel & Bauml, 2019).
- Results similar to list method when participants were asked (instead of receiving a forget cue) to imagine what their life would be like if they were invisible.
7
Q
intentional retrieval suppression: the think no think paradigm Anderson et al., 2004- methods
A
- Based on the idea of the go-no go studues about how we control action s
- To what extent do we have control over our memories
- Involves 3 phases
- Phase 1-Training
- Ss learn a series of unrelated word-pairs
- …pen-cherry, table-crane, glass-fur…
- Phase 2-Experimental session (multiple presentation of cues)
- Some pairs (pen-cherry) are tagged as respond (Think):
- “when you see the cue pen think of its pair”
- Some pairs (table-crane) are tagged as suppress (No Think):
- “when you see the cue table do not think of its pair”
- Some pairs (glass-fur) are not repeated (Baseline)
- Phase 3-Test
- All pairs are tested and participants are asked to try hard to remember
“….try to remember the word that was paired with pen”
- All pairs are tested and participants are asked to try hard to remember
8
Q
intentional retrieval suppression- the think no think paradigm behavioural results
A
- Recall for No Think pairs worse than the baseline (but no difference for Think pairs).
- Forgetting increases (recall drops) with successive suppression attempts.
- Forgetting under strategic, executive control
- People are actually forgetting this information
Active inhibition of retrieval.
9
Q
intentional retrieval suppression- the think no think paradigm brain activity
A
- No Think-Think contrast.
- In blue (circled) are areas showing reduced activity during suppression (Forget!) trials.
- Bilateral anterior hippocampi
- In yellow/red (squared) are areas showing increased activity during suppression (Forget!) trials.
- Ventrolateral prefrontal cortex (VLPFC)
- Dorsolateral prefrontal cortex (DLPFC)
- Anterior cingulate cortex (ACC)
- Intraparietal sulcus (IPS)
- Increased activation in DLPFC & left VLPFC predicted increased memory inhibition in the behavioural task.
- More activity we see- greater inhibition
- Same areas that are also involved in action control- brain recruits similar areas in both task
- Other non-memory but similar tasks that also require subjects to override strong responses also activate the DLPFC, the VLPFC and the ACC.
- The hippocampal reductions are in agreement with the well known role of the hippocampus in memory processes and in memory encoding in particular. Suppressed activity of the hippocampus may explain the fact that these items were subsequently less likely to be remembered.
In addition, the study provided some evidence of executive control over the hippocampus. Increases in DLPFC correlated with increased suppression for SF items in the right hippocampus.
10
Q
transcience- motivated forgetting
A
- There is strong evidence that we can explicitly and to a certain extent control what information we will remember or forget.
- Can do that not just by manipulating whether process items or not but we can actually engage a mechanism that can allow us to erase memories from our past
- Significant evidence to suggest a network of structures in the brain that can accomplish this
- This can be accomplished not just by controlling encoding (i.e. pay more attention) to the information we wish to remember but by actively suppressing unwanted memories.
- Studies using the think/no think paradigm have also revealed a network of brain structures which interact to suppress memories.
Not all studies have replicated the results of the think/no think paradigm; the neural correlates of conscious and unconscious suppression mechanisms are still under investigation.
11
Q
absent mindedness- encoding errors
A
- Very often, we fail to remember because the memory was never encoded properly.
- The memory and information that we are trying to retrieved was not properly created or stored
- E.g. not paying attention to what we are doing or we encode information in a way that is not useful for what the retrieval task is wanting us
- We tend to encode more efficiently when we focus our attention and process information at a semantic level, or when the encoding operations are best suited to future retrieval demands.
- So, most of the failures will be either due to slips of attention or inefficient/inappropriate information processing.
- As an example, we can look at how the use of technology can cause memory problems.
12
Q
use of GPS and spatial memory
A
- Global Positioning System (GPS) is a satellite-based system that provides spatial navigation guidance in real time and tends to be pretty accurate.
- Includes both visual and voice instructions. It has replaced the need for maps.
- Can be part of multiple devices (phones, smart watches, computers)
- No need to remember where to go as we have the satnavs to listen to to guide us
May affect our memory for routes for different locations
13
Q
does gps use affect spatial memory- Gardony et al., 2015
A
- In Gardony et al. (2015) participants were asked to navigate different virtual environments in four conditions: With and without GPS, both with attention divided and undivided.
- They first saw an overhead view of the environment and then navigated across 10 landmarks (city hall, hotel, library, garden, etc.).
- Receiving GPS-type instructions made it much easier for participants to navigate through the unknown environment, in particular in the undivided condition.
- After completing the navigation task, spatial memory was tested in a variety of ways including:
- Landmark recall
- Map organisation
- Pointing
- The aid (GPS-like instructions) affected memory only in the undivided attention condition. It did not have any impact in the divided attention condition.
- The presence of navigational Aids such as GPS affect the creation of new spatial memories by reducing people’s attention to spatial information.
GPS does not enhance memory or benefit you
14
Q
emotional bias
A
- Bias is the preferential treatment of specific types of information or in this case memories
- Emotional control over our memories
- Studies suggests that if we were to look back over our life and try to remember the prominent memories that define our life we tend to choose positive memories- much fewer negative ones
- They way we see our past tends to be much more of a happy place overall
- When asked to note (autobiographical) memories that come to their mind effortlessly, people show a tendency to retrieve more pleasant than unpleasant memories.
- In one study, 49% were pleasant and only 19% unpleasant (Bernsten, 1996).
- We also tend to remember the positive more than the negative feedback that we receive (Sedikides & Green, 2000).
- This does not extend to all negative information.
- We remember negative feedback directed towards others especially those we do not personally know!
- We do not do the same to ourselves or the people we like- bias as we control the way we see our past in order to produce a rosier look
Put into a model- inconsistency negativity neglect model
15
Q
emotional bias- the inconsistency negativity neglect model sedikides and green, 2000)
A
- The Inconsistency-Negativity Neglect Model (Sedikides & Green, 2000)
- Way we see our past is not primarily concerned with accuracy- mould our memories in a way that does not interfere with our self conception
- Drop the memories that go against the essence of who we are
- Individuals are “motivated to neglect the processing of information that challenges their positive self-conceptions […] The more challenging the information is, the more likely the individual will be to neglect it.” (p. 909)
- Feedback inconsistent with self image and which targets central self-conceptions is seen as particularly threatening because it affects the stability of the self-concept.
- Ignoring negative feedback ensures stability of self-concept.
- Primary aim is not to have an accurate account of what happened- we do not want our past to interfere with our emotional stability
If there is information that goes against it it is dropped
16
Q
emotional bias in the elderly
A
- Older adults show a positive affect bias in their learning and memory.
- Cognitive decline with age- also change in emotional control
- Much bigger emotional control or put much more emphasis in emotional goals
- Although overall memory performance drops with age, older people remember a greater proportion of positive than negative stimuli compared to the young.
- This relates to both the encoding of new information and retrieval of autobiographical memories.
- Similar effects have also been found with Chinese participants suggesting cultural independence-
- Older people much more content- reciprocal connection with memory
- Build more positive memories which support their personal wellbeing and are consistent with emotional goals
Not culturally specific
- Build more positive memories which support their personal wellbeing and are consistent with emotional goals
17
Q
emotional bias in the elderly (Mather & Cartensen, 2005)
A
- Socioemotional selectivity theory suggests that the consideration of one’s “time horizon” (how much we think we have left to live) influences our goals and motivation.
- Time horizon- how much time we think we have left and that will influence what our prioroties and goals are
- Short horizon: place much more significance on emotional wellbeing whereas when you have a longer horizon they concentrate on other things such as novelty and ambition
- With a short time-horizon, greater emphasis is placed on emotional states and improving our sense of wellbeing.
- Under normal conditions, elderly have a shorter time-horizon and that explains their memory (and also attentional) bias
- When the time-horizon for younger people changes (e.g. terminal illness), a positive affect bias also emerges. Conversely, if older people believe that their lives can be extended, the positive bias reduces.
- Can experimentally manipulate this e.g. young people with terminal illness- need much more emotional support (goal shift)
- Time horizon is important because it changes the way we approach the world and determines the goals we set
18
Q
own race face bias
A
- Own race face bias (ORB) (also known as the cross race or other race face effect)
- People tend to remember faces of their own race better than faces of other races
- For example, white participants will have worse memory for black than white faces and vice versa
19
Q
false memory
A
- Can we create false memories that are indistinguishable from real memories?
- The Deese, Roediger & McDermott paradigm:
- Ps are shown a series of words which are all highly associated with a lure word that is NOT studied:
- study: thread, pin, sewing…sharp, haystack, injection
- they are all strongly associated with needle (related lure-not presented)
- On free recall and recognition memory tests the related lure was retrieved as often as any of the presented words, the true targets.
- Not only were the lures retrieved but these memories were also judged to be as vivid and rich in contextual detail as any true memory (look at remember scores at bottom graph).
- Rate of false memories is very high, comparable or slightly lower than that of true memories.
- Participants’ subjective experience does not discriminate between true & false memories.
- False memory can be more robust than true memory:
- Increasing the number of unrelated words in the list affects true but not false memories.
- Levels of processing does not affect false recognition.
- Repeated tests following a single presentation increases the false memory rate.
- Tested at longer delays false memories are better retained than true memories.
- Divided attention at either study or test impairs both true & false memories.
BUT false and true memories differ in reported sensory detail
20
Q
Theories of false memory: active associative responses- Roediger & McDermott, 1995
A
- During encoding, the processing words which are semantically linked to a target word will also activate by association the target word.
- Because the target word has been activated by a number of different words its overall activation level is high.
- At test, participants retrieve information on the basis of its activation strength making it likely that a target word will be falsely retrieved.
- …Or, because the target was activated at study by association, participants believe that they have actually experienced the item whereas in fact they have only thought about it. False memory then is similar to a source error.
21
Q
Theories of false memory: Gist memory & sensory reactivation (Schacter, 1999)
A
- Schacter (1999):
- Presentation of word lists consisting of semantically related items creates a certain theme, a well organised representation of the “gist” of the study list.
Participants then approach the task by relying on their memory for the “gist” rather than individual features and as a result they make more semantically related errors.
22
Q
False memories: evidence from functional neuroimaging: Cabeza et al., 2001
A
- In this study, participants heard lists of words (related lists) spoken by two different speakers.
- At test, while in the scanner, they were asked to recognise studied, related false and unrelated false words.
- As expected they showed high levels of related false alarms.
- Brain (haemodynamic) responses to related false items were almost identical to studied items in prefrontal and hippocampal sites. These areas were influenced by semantic similarity.
By contrast, parahippocampal cortex which is involved in perceptual processing classified related and unrelated false alarms together as neither class of item had a pre-existing perceptual record.
23
Q
False autobiographical memories (Loftus, 1975)
A
- Suggestibility through misinformation (Loftus, 1975).
- But can we implant false autobiographical memories?
- Is it possible to convince people that specific events happened during their childhood to the extent that they can then produce false memories related to the event?
- Studies have intermixed false and true events and asked people to recall their memories of these events.
- The number of people that are susceptible to false recall varies considerably among studies possibly due to a number of factors including the plausibility of the event, their emotional significance, scoring method among others.
24
Q
Loftus 1975 procedure
A
- Technique involves:
- Participants get a description of several real and one false childhood event
- True events supplied by family acting as confederates
- Asked to remember details of the events over 2-3 interview sessions
- Wade et al. (2004) went a step further and manipulated pictures of events to involve the participants when they were children. Pictures…
- Are considered objective, reliable, undisputed evidence of a plausible event
- Provide a lot of detail that can be used to construct a memory narrative
25
Loftus 1975 results
- “At Interview 1, 1 subject reported a clear false memory, 6 reported partial false memories, 3 were trying to recall, and 10 had no memory responses.”
- “By Interview 3, the one clear false memory remained clear; two partial false memories became clear; and one trying to recall false memory developed into a clear false memory. The other four partial false memories stayed partial false memories, whereas two trying to recall memories became partial false memories.”
- “Of the 10 no memories at Interview 1, half remained so, and the other half became trying to recall memories. In short, at the end of the three interview sessions, a total of 10 (50%) subjects recalled the false event either partially or clearly—claiming to remember at least some details of a hot air balloon ride during childhood.”
True memories more confident than false
26
three stages of implantation
- An individual…
- Accepts that the event is plausible
- Generates contextual information for the event (could be a mental image, a story, etc.)
- Misattributes the created event to personal experience rather than a mental construction
I would add a precondition: Weak memory for the specific life period
27
social influence and memory errors
- Social influence is known to affect the formation of social norms, opinions attitudes and their expression in behaviour
- Is memory a process that operates in a social vacuum or can it be altered by what other people remember?
- The vast majority of studies involve individual encoding and retrieval.
- A relative small number has looked at memory in a social context
- Apart from scientific curiosity is there something else to be gained by this type of research?
28
social influence and memory
- On 19th April 1995, Tim McVeigh and an accomplish carried out a bombing attack on a federal building in Oklahoma City, USA.
- The bomb killed 168 people and injured more than 680 others.
- McVeigh was arrested, sentenced to death and executed by lethal injection.
- The Oklahoma city bombing represents the deadliest domestic terrorism attack in the USA.
29
social influence and eyewitness testimony
- As part of their investigation into the Oklahoma city bombing, the FBI were looking for an additional accomplice who together with the main perpetrator (T. McVeigh) had rented the car that was used in the attack.
- Although McVeigh had accomplishes, they were not with him when he rented the car.
- The misleading information was due to eyewitness testimony:
- Witness 1 claimed to have seen a second man
- Witness 2 initially denied the man’s existence but later changed his testimony.
- It later emerged that witness 2 changed his testimony after discussing the incident with witness 1. Is it possible that the discussion made witness 2 accept a memory that was not his own?
- How accurate and independent can eyewitness testimony be if witnesses discuss the event?
30
informational influence
- Motivated by the need to be accurate. Subject adopts the opinions of others as evidence about reality
- Sensitive to degree of uncertainty
- Proposed to explain the formation and change of social norms
- Informational influence likely to result in both public conformity & private change
- Present when S is tested individually
- Can persist for a long time (permanent change)
Information influence affects both behaviour and memory.
31
normative influence
- Motivated by the need to be accepted and considered part of the group.
- The subject conforms to the opinions of the majority even when there is little doubt that the majority view is incorrect
- Sensitive to size of majority, attractiveness of the group, interdependence between individual and group
- Reduced when dissenter is present
- Proposed to explain the influence of the group even to matters of undisputed fact
- Normative influence likely to result in public conformity BUT NOT private change
- Likely eliminated when S is tested individually
Normative influence affects behaviour but not memory.
32
social contagion- Roediger et al., 2001
- Social transmission of false memories
- Participants and a confederate viewed six photos of house scenes and then took turns to recall as many items as they can from each.
- For two of the scenes the confederate made a false recall (mentioned an item not in the scene). These were the critical items.
- Manipulated memory strength
- One group looked at each scene for 15s the other for 60s
- Manipulated semantic relatedness of false memories
- High and Low probability (semantic relation of item to the scene-likely to be in that photo)
- Individual recall
- Probability of false recall of critical item vs. baseline & quality of memory
- Strong effects of social influence (greater than baseline)
- Greater conformity when memory was weaker
- Memory strength correlates negatively with conformity
- Greater conformity for high vs. low probability items
- If a false memory “belongs more” to the scene, conformity is greater
- Effect appears greater for know responses
Related more to familiarity than recollection
33
social influence effects on memory- possible mechanisms
- Explanation for the social influence effect have mainly tried to discuss implantation of false memories
- Social influence errors are source memory errors
- Item information recalled but source is lost (misattribution)
- False memory is greater if similar to the schema of the episode (gist memory)
- Efforts to reduce source memory errors reduce conformity
- Drawing attention to the source of information
Distinctiveness of false memory (dissimilar to episode)
34
Meissner and brighams 2001 meta analysis
- People are more likely to correctly recognise a face of their own race (greater number of true positive identifications) and incorrectly recognise a face of another race (greater number of false positive identifications).
- People are more cautious to say that they have seen own race faces (more conservative criterion) than other race faces (more liberal criterion).
- Shorter exposures and longer retention intervals increase the other race effect (own>other) suggesting a link between weak encoding and face effect.
- Research has a clear and important applied focus in relation to eyewitness testimony.
- The ORE can be found across racial groups.
* Caucasians show good discrimination for Caucasian faces, Black for Black, Chinese for Chinese but a relative impairment for others
- Some early evidence that white participants show greater other race effect than (at least) black participants.
- Amount of interracial contact is a significant but weak predictor of the ORE
* Racial attitudes do not appear relevant (but difficult to measure reliably and meaningfully)
35
does other race contact matter?
- Meissner & Brigham’s (2001) meta-analysis found significant but weak correlations (r= -.13) with amount of contact.
- A more recent meta-analysis (Singh et al. 2021) replicated the earlier findings (r= -.15) and identified additional moderators:
* If we experimentally manipulate contact (i.e. train participants), effects are higher than if we simply measure individual differences in other race contact.
* Contact early in life (infancy and childhood) reduces the ORE more than later contact (adolescence and adulthood) suggesting the need for hard-wired changes in the brain.
BUT, quantity and quality of ORE contact is difficult to measure accurately and studies vary widely in the instruments they use making any firm conclusions difficult.
36
developmental evidence- Kelly et al., 2007
- Infant studies rely on indirect measures of memory. Memory is inferred by measuring how long infants spent looking at novel faces in pairs consisting of a novel and a studied face.
- Infants show habituation to studied faces. These faces have become familiar and therefore there is no need to explore them as much as novel faces.
Looking to the novel face for longer suggests memory for the studied face in the pair. No difference in looking times suggests lack of memory.
37
Developmental evidence- early and gradual development of memory effect (Kelly et al., 2007)
- Early and gradual development of memory effect.
- No effect at 3 months but it appears fully developed by 9 months.
- There was also some evidence that at 6 months, infants were more likely to look at novel Chinese and Caucasian faces than expected by chance-see dotted baseline at 50%.
Although the mean looking times for African and Middle-Eastern faces at 6 months were similar to Chinese and Caucasian faces, infant responses were more varied.
38
developmental evidence- Sangrioli et al., 2005
- Although other race effects can appear quite early, do they remain fixed or can they be reversed?
- Korean adults who between the ages of 3-9 years were adopted and raised by Caucasian families in Europe showed a memory effect for Caucasian and not Asian faces.
- It appears that the system or processes responsible for other race effects are plastic (i.e. subject to change). Theories of the effects should include mechanisms to account for such plasticity.
Recent evidence suggests that this “other race face plasticity” ends by the age of 12 (McKone et al ., 2019).
39
face processing resources
- If processing own race faces is more resource demanding, then reducing our available resources should eliminate the other race effect.
* Reduced other race effect
- If processing of other race faces is more laborious (resource intensive), then reducing available resources should increase the other race effect.
Greater other race effect
40
the role of attention on the other race effect (Zhou et al., 2015)
- Zhou et al. manipulated attention to examine the effects of resource availability and allocation in the ORE.
- One group studied own and other race faces under full attention conditions. A second group had their attention divided between face processing and another task (tone detection).
- The results showed that under full attention there was a clear other race effect (own>other). With divided attention the effect disappeared (own=other).
- Own race processing is more attention and resource intensive. We engage same processes more or use additional processes when dealing with own race faces.
In agreement with findings of slower race classification of own compared with other race faces which suggests that own race faces receive additional processing.
41
expertise based theories on the other race effect
- Expertise theories: Lack of contact between races (racial segregation) responsible for developing greater expertise in processing and/or remembering members of the same race better than those of other races.
- Does effective racial segregation exist
- Developmental evidence discussed earlier is in line with the predictions of expertise theories.
* No initial differentiation but effect develops quickly.
* Effect can be reversed at least at a young age.
Two main expertise-based theories: differential processing mechanisms theory; representational theory.
42
configural processing
- Faces are processed configurally: Configural processing involves the extraction of the relationships between permanent facial features (e.g. eyes, nose, mouth) and enables the processing of the face as a whole rather than a collection of individual features.
* Face-specific processing detected early in brain potentials (differences in ERPs visible by 200ms).
- Evidence of configural processing can be seen in studies that present inverted (upside down) faces.
Inversion disturbs the relationship between features (e.g. eyes no longer above nose and nose no longer above mouth). Recognition accuracy drops significantly for all inverted faces.
43
configural processing and the other race effect (Rhodes et al., 1989)
- Configural processing is related to expertise. We are more likely to process something as a whole if we have a lot of experience with the particular item.
- Reduced contact with other race faces will make them less likely to be processed configurally.
- If same race faces are processed configurally but other race faces are not, then face inversion will affect same races faces more than other race faces.
Rhodes et al. (1989-see next slide) found exactly this. Viewed inverted, other race faces were recognised equally well to same race faces.
44
representational models- the face space model
- Representational models explain the face race effect with regards to memory representations.
* No difference in how faces are processed initially
- The face-space model (Valentine, 1991) assumes that each facial feature and inter feature relationships are normally distributed in a population and represented as dimensions of the face’s memory representation.
* Multiple dimensions define face space
- Each face is encoded on each dimension and represented in memory space by its coordinates. Most faces will be close to the average with few outliers
* Typical and atypical faces
- The number of dimensions is defined by and evolves with the number of exemplars. Same race faces are more frequent and will be responsible for shaping the dimensions. The more dimensions, the greater the spread of exemplars in face-space (more distinctive).
- Other race faces may not conform fully to the established dimensions and will be seen as atypical and will be represented by fewer dimensions. As a result they will be represented in a smaller, denser face-space.
- It will be more difficult to distinguish between other race faces than for same race faces and recognition will suffer.
More false alarms for other race faces
45
critique to the experience based models- Meissner and brighams 2001 meta analysis
* There is only weak evidence that amount of contact with other race faces is responsible for the other race effect in adults.
* But that may be due to the fact that measures of contact rely on self-report and are not particularly sensitive.
- But quality of interracial contact may be a better measure
* Will consider individuation studies later.
- Not all studies have found evidence that disruption of configural processes eliminates the other race effect.
- In the face-space model, the actual dimensions are not specified. Training to improve discrimination has short-term effects. We look into some findings that experience-based models cannot easily explain.
46
angry faces
- Angry facial expressions capture our attention (more resources allocated) because:
* Signify threatening intent and potential danger. Should be detected!
* It is also important to encode individuating characteristics of angry persons to make sure you remember them even when angry expression disappears (as the threatening intent may still be present).
* Anger expressed by out groups may be perceived more threatening than in groups.
Angry faces- Ackerman at al., 2006
- An other race effect was only seen with neutral faces.
- Angry faces were recognised equally well across races.
- This finding is difficult for processing and representational theories to explain.
- It is not clear how people overcome fundamental processing and representational shortcomings without extensive training.
47
The ambiguous race face effect (McLin & Malpass, 2001; 2003)
- What happens when the faces are racially ambiguous?
- Faces (on the right) are identical apart from a single, race specifying characteristic (hair).
- According to experience-based models there should be no memory differences between the Hispanic and Black looking faces.
- Yet, Hispanic participants were more likely to remember the Hispanic looking faces than the Black looking faces.
“…other race faces are encoded categorically and …categorization drives the perceptual process” (MacLin & Malpass, 2001, p.112)
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Race is not the only issue (Wiese et al., 2013)
- Several studies (e.g. Rhodes & Anastasi, 2012; Wiese et al. 2013) show other age effects where young and old participants tend to remember faces of their respective age groups better.
Others report differences in face recognition based on sex (Herlitz & Loven, 2013) with women more likely to remember female than male faces. No sex bias is seen in men.
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Social bias: the ingroup face effect (Bernstein et al., 2007)
- Bernstein et al. (2007) tested Miami University students’ memory for faces they believed depicted members of either the same or a different University
- A control group saw the same faces but without affiliation information.
In a second experiment, participants were told that one group (e.g. red) matched their own personality group (in-group) whereas faces on green background did not (out group).
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socio cognitive models
- Explain other race effects as a result of social factors:
* Own Race=in group
* Other Race(s)=out group
- As we have seen previously, group membership of a real or artificial group can have powerful effects on face processing and face recognition.
- Socio-cognitive models can also explain other face effect phenomena: Other age effect, other sex effect, etc.
- If true, other race effects can be susceptible to change of social dynamics and thus reversible.
But they still consider expertise with other race faces to play a role.
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In group/out group model- Sporer, 2001
- Social perception is the first step in face processing
- In-group faces follow a series of default, automatic processing steps
* Automatic in this model does not mean effortless
* Configural coding due to expertise with faces
* Level of memory performance and response criterion will depend on test conditions
- Out-group faces have an extra initial step: categorisation as an outgroup. This may be triggered by an obvious visual characteristic (skin colour, hair, nose, etc.).
- Depending on contextual factors different processes may follow outgroup faces
* Cognitive disregard stops encoding and redirects attention.
* Superficial processing and stereotyping leads to inferences (“dark eyes go with darker skin”).
* Lack of expertise leads to adoption of incorrect dimensions and criteria (e.g. hair may not be a differentiating characteristic for a specific race)
* Verbal processing leads to replacement of visual with verbal coding which is not useful when face similarity is high
All factors make discrimination between targets and distractors difficult leading to reduced recognition and more false memories
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Categorisation- individuation
- Categorisation focuses on shared characteristics of a group of exemplars.
- Aim is to confirm/reject category inclusion
- Quick, effortless, spontaneous process
- Individuation focuses on facial characteristics unique to the individual exemplar’s identity.
- Aim is to process what makes the individual unique
Effortful and resource intensive (effects of attention discussed earlier)
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Individuation motivation
- Motivation to individuate required for process to take place. Motivation modulates attention and deeper processing.
- Categorisation appears as the default form of processing in many everyday contexts.
- Do you remember the face of the bus driver?
- Change blindness
Other race effects emerge partly because we lack motivation to individuate other race faces. Same applies for age and more complex for sex effect.
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Motivation interacts with perceptual experience
- Motivation to individuate is likely to vary depending on pre-existing social differences as well as current demands and needs.
- Perceptual experience with other race faces is not sufficient for individuating processing; it has to be coupled with motivation to do so.
On the other hand, motivation in the absence of perceptual experience will result in limited improvements in performance.
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Eliminating race effect- individuation
- Individuating processing
- Can we eliminate the other race effect by encouraging participants to engage in the processing of individual characteristics of other race faces?
- Studies provide instructions that inform participants of the other race effect and ask them to:
- “…pay close attention to what differentiates one particular face from another face, especially when that face is not of the same race as you ... Remember, pay very close attention to the faces, especially when they are of a different race than you in order to try to avoid this Cross Race Effect.'‘ (Hugenberg et al 2007, p. 336-337)
Some studies find an effect, some don’t.
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Eliminating race effect
- If the other race effect is due to in-group effect (i.e. social categorisation) can we eliminate it by manipulating social categorisation? An earlier study did not support this (Shriver et al. 2008) as race categorisation is considered automatic.
- Hehman et al. (2010) suggested that the ORE can be eliminated when (same) group affiliation is reinforced by spatially grouping together Caucasian and black faces during encoding.
- But Kloth et al. (2014) failed to replicate these findings. In their study, the ORE was present irrespective of the way faces were grouped on the screen.
- One reason for the discrepancy might be the value placed on in-group identity by different participants across studies.
