Psych Unit 1, Cognitive processes, Case Studies

Atkinson and Shiffrin

Atkinson and Shiffrin

Atkinson and Shiffrin's (1968) multistore model case study aimed to investigate memory processes. Employing rehearsal tasks and reaction time measurements, they identified three memory stores: sensory, short-term, and long-term. Findings emphasized the sequential flow of information through these stores.

Key terms: sensory memory, short-term memory, long-term memory and rehearsal

Sperling

Topic: Cognitive processing

Content: Multi-store model

Trigger: iconic memory of a tachistoscopic image

Aim: Investigate duration and capacity of iconic memory within the multistore model.

Procedure:

• Participants view a brief (50 ms) grid of alphanumeric characters in a tachistoscopic image.

• Tone signals played 50 ms after the image appeared prompted recall of either the whole grid or a specific row.

• Partial report resulted in the remembering of a single row, entire meaning the entire grid

Findings:

• Higher-than-expected recall in partial report conditions.

• Suggests existence of fleeting iconic memory.

Key Terms:

• Iconic memory: Brief visual sensory memory.

• Sensory memory: Initial stage in memory process.

• Partial vs. whole report: Varying recall amount in experiments.

• Multistore model: Framework with distinct memory stores.

Glanzer and Cunitz

Topic: Cognitive processing

Content: Multi-store model

Trigger: Serial positioning effect w delayed recall

Aim: Investigate the impact of position in a list on recall within the multistore model.

Procedure:

• Participants (240 enlisted army men) were presented with a list of 20 words consisting of common one syllable nouns.

• Immediate and delayed (30 seconds counting backwards) recall tasks employed.

• Primacy and recency effects observed, for participants with delayed recall condition, recency effect was lost.

Findings:

• Better recall for words at the beginning (primacy effect) and end (recency effect) of lists.

• Middle items less recalled.

Key Terms:

• Serial Position Effect: Varied recall based on item position within a list.

• Primacy Effect: Better recall for items at the list beginning.

• Recency Effect: Enhanced recall for items at the list end.

• Multistore Model: Framework proposing distinct memory stores.

HM (Scoville and Milner)

Topic: Cognitive processing

Content: Working memory model

Trigger: Bilateral medial temporal lobe, memory formation

Aim: Investigate the effects of bilateral medial temporal lobe resection on memory and identify brain regions crucial for memory formation.

Procedure:

• H.M. underwent bilateral removal of medial temporal lobes to alleviate severe epilepsy.

• Extensive memory assessments conducted over several decades.

• Longitudinal neuropsychological examinations tracked changes in memory function.

Findings:

• Profound anterograde amnesia: inability to form new long-term memories.

• Intact short-term memory and preserved preoperative memories.

• Revealed that muscle memory and the MSM model are different lobes of the brain, due to HM’s ability to learn mobility exercises through repetition, star test.

Key Terms:

• Anterograde Amnesia: Inability to form new memories post-incident.

• Medial Temporal Lobe: Brain region crucial for memory consolidation.

• Longitudinal Study: Examination over an extended period to observe changes.

• Memory Consolidation: Process of stabilizing and storing memories.

Baddely and Hitch

Topic: Cognitive processing

Content: Working memory model

Trigger: Dual-task activities (verbal and visual-spatial)

Aim: Investigate the components and processes of working memory, challenging the existing unitary and one directional model of short-term memory.

Procedure:

• Participants performed various dual-task activities to explore simultaneous processing demands.

• Tasks involved verbal and visual-spatial information.

• Observations made on the impact of concurrent tasks on performance.

Findings:

• Working memory involves multiple components: Central Executive, Phonological Loop, and Visuo-spatial Sketchpad.

• Dual-task performance differed based on the nature of the tasks.

• Established a more comprehensive model beyond the simplistic short-term memory model.

Key Terms:

• Working Memory: System for temporarily holding and manipulating information.

• Central Executive: Component controlling attention and coordinating other subsystems.

• Phonological Loop: Handles verbal and auditory information.

• Visuo-spatial Sketchpad: Manages visual and spatial information.

• Episodic Buffer: integrates information from other systems in order to link them, same with linking LTM and STM

Landry and Bartley

Topic: Cognitive processing

Content: Working memory model

Trigger: articulatory suppression

Aim: Explore the impact of articulatory suppression on memory performance to understand the role of verbal rehearsal in memory tasks.

Procedure:

• Participants engaged in memory tasks while simultaneously performing repetitive verbal articulation (saying 1 2 1 2 1 2 at a rate of 2 numbers per second).

• Participants were given 10 lists of 7 letters which were phonologically dissimilar

• Given 1 list at a time, participants were made to recall the list on a blank paper

• Comparisons made between conditions with and without articulatory suppression.

Findings:

• Articulatory suppression negatively influenced memory performance, particularly for verbal tasks

• there was a accuracy of 78% for the control group, and a score of 45% in the experimental group

• Verbal rehearsal plays a significant role in memory encoding, meaning that overload causes decrease in accuracy during recall

• Supported the idea that articulatory control affects cognitive processes.

Key Terms:

• Articulatory Suppression: Disrupting memory by engaging verbal articulation.

• Verbal Rehearsal: Repetitive verbal processing aiding memory encoding.

• Memory Tasks: Activities assessing the ability to recall information.

• Cognitive Processes: Mental activities involved in acquiring and processing information.

Bartlett

Topic: Cognitive processing

Content: Schema theory

Trigger: Native American folktales, reproducing the story from memory

Aim: Investigate how cultural schemas influence memory recall and reconstruction, challenging the traditional view of memory as a passive storage system.

Procedure:

• Participants read and recalled unfamiliar Native American folktales.

• Memory recall was assessed over time, with participants reproducing the stories from memory.

• Bartlett observed how participants altered the details to fit their cultural schemas.

Findings:

• Memory recall is influenced by cultural schemas and prior knowledge.

• Participants tended to transform and simplify information to align with their cultural expectations.

• Introduced the concept of "schema" as a cognitive framework shaping memory.

Key Terms:

• Schema Theory: Cognitive framework influencing the encoding and retrieval of information.

• Memory Recall: The process of remembering previously learned information.

• Reconstruction: Altering and reshaping memories during recall.

• Cultural Schemas: Shared beliefs and expectations influencing cognitive processes.

Bransford and Johnson

Topic: Cognitive processing

Content: Schema Theory

Trigger: no title, before and after, contextual information (schemas)

Aim: Investigate how the use of contextual information (schemas) affects memory encoding and retrieval processes.

Procedure:

• Participants exposed to passages with ambiguous content.

• Varied presentations with or without a relevant title to establish or disrupt a schema, conditions of ; No title, Title before and Title after.

• Memory recall and comprehension assessed through questions about the passages.

Findings:

• The presence of a schema (relevant title) significantly improved memory recall and comprehension.

• Schemas aid in organizing and encoding information, enhancing retrieval.

• Demonstrated the impact of top-down processing in memory, emphasizing the role of context.

Key Terms:

• Schemas: Cognitive frameworks that organize and interpret information.

• Memory Encoding: The process of converting information into a form suitable for storage.

• Retrieval: Recalling stored information.

• Top-Down Processing: Using pre-existing knowledge to interpret and make sense of new information.

Brewer and Treyens

Topic: Cognitive processing

Content: Schema theory

Trigger: Office schema consistent and inconsistent objects, deception.

Aim: Investigate the influence of schema on memory by examining participants' recall of objects in an office setting.

Procedure:

• Participants waited in an experimenter's office, later asked to recall its contents.

• The office contained both schema-consistent and schema-inconsistent items (e.g., skull and picnic basket).

• Memory recall and recognition tasks assessed participants' ability to remember office items.

Findings:

• Participants tended to recall items that were schema-consistent, even if those items were not present.

• Schemas shape memory, leading to the incorporation of expected but absent elements.

• Highlighted the role of schemata in guiding perception and influencing memory.

Key Terms:

• Schema: Cognitive framework influencing perception and memory.

• Recall: Retrieving information from memory.

• Schema-Consistent: Items aligning with participants' expectations.

• Schema-Inconsistent: Items conflicting with participants' expectations.

Loftus and Palmer #1

Topic: Reliability of cognitive processes

Content: Reconstructive memory

Trigger: speed of car based on priming word

Aim: Investigate the impact of phrasing questions on eyewitness memory and the potential for leading questions to influence recall.

Procedure:

• Participants watched a film depicting a car crash.

• Different groups were asked about the crash using varied verbs (e.g., hit, smashed, collided).

• Participants later recalled details of the event.

Findings:

• Different verb choices influenced participants' estimates of the speed of the cars.

• The verb "smashed" led to higher speed estimates than "contacted."

• Demonstrated the malleability of memory and the susceptibility of eyewitnesses to suggestion.

Key Terms:

• Eyewitness Memory: Recollection of events observed by an individual.

• Leading Questions: Questions that subtly suggest a desired answer.

• Verb Choice Effect: The influence of wording on memory recall.

• Malleability of Memory: Memory's susceptibility to distortion and suggestion.

Loftus and Palmer #2

Topic: Reliability of cognitive processes

Content: Reconstructive memory

Trigger: Memory change of glass due to primer word.

Aim:

to investigate if participants who had a high-speed estimate in the first part of an experiment would say that they had seen broken glass in the second part of the experiment. The researchers hypothesized that this would happen.

Procedure:

150 students participated in this experiment. They were randomly allocated to conditions. They were shown a 1-minute film depicting a multiple-car accident lasting around 4 seconds. After seeing the film the participants answered a questionnaire. First, they described the accident in their own words, and then they had to answer a number of other questions. Fifty participants were asked:” About how fast were the cars going when they smashed into each other?” Fifty participants were asked:” About how fast were the cars going when they hit each other?” The remaining fifty participants were not asked to estimate speed.

After one week the participants came back to the laboratory to answer some questions about the accident. There was one critical question this time in a list of a total of 10 questions and it was placed randomly in the list in the questionnaire. The critical question was:” Did you see any broken glass?” The participants simply had to answer “yes” or “no”. In fact, there was no broken glass in the accident the participants had seen but the researchers assumed that broken glass was associated with high speed.

Findings:

The mean estimate of speed by the participants who had the critical question: "About how fast were the cars going when they smashed into each other?” was 10.46 mph. The mean estimate of speed by participants who had the critical question:” About how fast were the cars going when they hit each other?” was 8.00 mph.

In the ‘smashed’ condition 16 participants said yes to having seen broken glass compared to 7 in the ‘hit’ condition. 6 participants in the control condition answered ‘yes’ to the question. 34 participants in the ‘smashed’ condition answered ‘no’ to the question compared to 43 in the ‘hit’ condition. Although most of the participants accurately reported no broken glass, more of the participants in the ‘smashed’ condition said they saw broken glass.

The researchers argued that the results of the second experiment provided further support for the theory of reconstructive memory and schema processing. The wording of the critical question led to higher speed estimates in the first part of the experiment and this also had consequences for how participants answered in the second part of the experiment. Loftus and Palmer suggest that participants are influenced by the perception of the event but also by the post-event information provided by the critical question. The researchers argue that this information may be integrated in such a way that it is difficult to say where it came from when the participants try to recall the event. The verb used in the critical question provides further information to the participant about the accident. The word ‘smashed’ gives the participant the idea of an accident that is severe and therefore he or she is more likely to think that there was broken glass.

Loftus Miller and Burns

Topic: Reliability of cognitive processes

Content: Reconstructive memory

Trigger: yield and stop sign, question with confirming (consistent) or contradicting (inconsistent) object

Aim: To investigate the effect post event information has on the recall of event specific iconic/visual memories.

Procedure:

In their 1978 study, Loftus and her co-authors showed participants a series of slides. In the sequence, a car stopped at an intersection and proceeded to turn and hit a pedestrian. Half of the participants saw a slide with a yield sign while the other half saw a slide with a stop sign. Twenty minutes to a week after the slides were presented, participants answered questions regarding the details of the accident. The questions consisted of ones that were consistent with the original slides, questions that were misleading and questions that were neutral.

Findings:

Loftus and her co-authors found that people who saw inconsistent information were much less accurate than people in the other two conditions. They also found that the longer the period of delay between when slides had been shown and when participants were tested, the less the percentage of answers subjects got right.

Yuille and Cutshall

Topic: Reliability of cognitive processes

Content: Reconstructive memory

Trigger: robbery, yellow car panel, broken taillight, high reliability of memory, leading questions

Aim: Investigate the accuracy and reliability of eyewitness testimony in a real-life, high-stress situation, challenging the notion that stress negatively impacts memory recall.

Procedure:

• Interviewed witnesses of an actual shooting incident in a gun shop.

• Compared police interviews with those conducted by researchers four to five months later.

• Assessed the consistency and accuracy of details provided by witnesses.

Findings:

• Witnesses showed high accuracy in their recall, even after several months.

• Stress did not significantly impair memory; in fact, it seemed to enhance it.

• Emphasized the importance of real-world context in understanding eyewitness testimony.

Key Terms:

• Eyewitness Testimony: An account provided by individuals who witnessed an event.

• Memory Recall: The process of retrieving information from memory.

• Stress and Memory: The relationship between stress and the accuracy of memory recall.

• Real-life Context: The significance of studying memory in authentic, high-stress situations.

Brown and Kulik

Topic: Emotion and cognition

Content: Flashbulb memory

Trigger: 10 shocking events, when they had learnt of them, 9 were assasinations, 1 was a self select, black vs white

Aim: to investigate the validity of FBM compared to recall of other events, and the effect of racial identity on it.

Procedure:

80 participants, 40 were white, 40 were black

they were asked to recall when they had learned of shocking events, and recall their memory on 10 events, 9 of which which were assasinations’ , one was selected by the participants. The participants were then asked whether they had/how much they had overtly or covertly rehearsed the events

Findings:

Participants of all races could remember where they were, how they were feeling and what they were doing during the shocking events. For black participants, the vividness of the memories of civil rights leaders assasinations’ were higher than in whites.

CT points:

there is no way to confirm the accuracy of the memories recall, as the vividness does not confirm accuracy or reliability.

Sharot et al

Topic: Emotion and cognition

Content: Flashbulb

Trigger: 9/11, event proximity’s role on accuracy and vividness of FB memories.

Aim: to understand the role of proximity to events and the vividness/accuracy of participant FB memories.

Procedure:

participants were on Manhattan during the 9/11 terror attack in varying proximities. The participants were placed in fMRI scanners and asked to recall memories from the attack and from a control event with no FB memory linked.

Findings:

83% of Participants who were in close proximity to the event (downtown Manhattan) showed selective activation of the amygdala when retrieving/recalling the events of the attack. only 40% of participants in Midtown showed activation.

CT point:

There is correlation between amygdala activation and the formation of FBM, or atleast highly emotional memories. However the accuracy of the memories cannot truly be tested, and the amygdala is not the only neuro-mechanism responsible for the formation of memories, therefor without the ability to be present at the conception of the FBM, there would be no way of knowing the precise mechanisms behind FBM formation.

Neisser and Harsch

Topic: Emotion and cognition

Content: Flashbulb memory

Trigger: Challenger mission, reliability of FB memories over time, 3 years later

Aim: to understand the reliability of FB memories over time.

Procedure: participants were given questionnaires the day of the challenger mission disaster, asking where they were, what they were doing, how they felt and how they heard of the event. The same participants were asked 3 years later the same questions.

Findings: participants answered the second questionnaire correct only 42% of the time. Despite this, participants were very confident in their accuracy of their memory and were unable to explain their low scores.

CT Point: The accuracy of the memories was low while still showing high vividness for participants. Due to the semantic nature of the memory and its highly emotionally derived origins, the emotive portions of the memory add the vividness and confidence in the reliability of the memory, despite change to the memory being clearly shown.

Kivetz and Simonson

Topic: Thinking & Decision making

Content: Thinking and decision making

Trigger: how T&D could be predictably flawed, wine bottle 50$ vs 55$ cash

Aim: to investigate how thinking and decision making could be predictably flawed/illogical in a realistic scenario.

Procedure: researchers asked 95 Americans, ranging in age from 18-80 years old whether they would prefer a lottery prize of 55$ or a 50$ bottle of wine.

Findings: Researchers found that 24% of the participants chose the wine rather than the cash (S1 engagement).

CT point: Researchers found that when participants slowed down the decision and engaged system 2, they would find that taking the wine would be illogical as they could buy the same bottle and still have 5$ left over. The choice of the wine bottle is illogical.

Tversky and Kahnmann

Topic: Biases in Thinking & Decision Making:

Content: Anchoring bias

Trigger: 600 people health programs, same fatality ration, anchoring bias.

Aim: to understand the impact of thinking and decision making by the phrasing of a choice, framing. Framing refers to the way a statement is presented, for example if a scenario is presented positively or negatively.

Procedure:

Researchers had participants choose between two health programs which 600 people would undergo for a potentially fatal disease. Treatment A (negatively framed); expected to result in 400 deaths

Treatment A (positively framed); expected to result in 200 lives saved

Treatment B; had a 33% probability of no death and a 66% probability of death.

Findings: 72% of participants chose treatment A when it was framed postively, but only 22% chose the same treatment when framed negatively

CT point: This shows the illogical nature of which framing impacts our decisions. Framing acts by presenting one of two different ways of presenting a decision, where one sounds better than the other, despite the fact that the outcome is the same.

Tversky and Kahnmann

Topic:

Content: Anchoring Bias

Trigger: 1×2…x7×8 and reverse, ascending and descending condition

Aim: To understand the effect of different anchors on estimation under conditions with high mental load

Procedure: In this study, high school students were used as participants.  Participants in the “ascending condition” were asked to quickly estimate the value of 1 X 2 X 3 X 4 X 5 X 6 X 7 X 8 in five seconds.

Those in the “descending condition” were asked to quickly estimate the value of 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1.

Since we read from left to right, the researchers assumed that group 1 would use "1" as an anchor and predict a lower value that the group that started with "8" as the anchor.  The expectation was that the first number seen would bias the estimate of the value by the participant.

Findings: The researchers found that the median for the ascending group was 512; the median for the descending group was 2250. The actual value is 40320.

CT point: High control, high replicability, high reliability, external validity, low EV.

Englich and Mussweiler

Topic: Biases in Thinking & Decision Making:

Content: Anchoring bias

Trigger: Length of a prison sentence based on time request, judge, prosecutor.

Aim: To know if the simple request for a certain length of a prison sentence would unduly influence the decision made by a judge.

Procedure: To test their hypothesis that the recommended sentence proposed by a prosecutor would unduly influence a judge’s decision, the researchers used an independent samples design.  This allowed the researchers to use the same case study for both conditions – the high anchor and the low anchor.

In order to control for the level of courtroom experience, the sample was made up of 19 young trial judges (15 male and 4 female) – with an average age of 29.37 and with an average of 9.34 months of experience.

The participants were given a case of alleged rape.  The prosecutor in one condition demanded a sentence of 2 months vs. 34 months.

To develop the case materials, advice was sought from highly experienced trial judges.  Then the case materials were tested on a group of 24 senior law students – this served as a pilot study.  The average recommended prison term suggested by the law students was 17.21 months.   This was then used as a basis for determining the anchors.

Participants were given the case materials along with copies of the penal code. They were asked to read through the materials and form an opinion about the case.  After they had formed an opinion about the case (about 15 minutes), they were given a questionnaire.  Half of the participants were told that the prosecutor demanded a 34-month sentence; while the other half were told that he demanded a 2-month sentence.

They were then asked the following questions:

• Do you think that the sentence was too low, adequate, or too high?

• What sentence would you recommend?

• How certain are you about your sentencing decision? (a scale of 1 – 9)

• How realistic do you think this case is? (a scale of 1 – 9)

Findings: The average rating for the realistic nature of the case was 7.17, with a standard deviation of 1.3.  The judges' certainty about their responses, however, was not as strong, with an average rating of 4.53 and a standard deviation of 2.29.

When presented with a low anchor of two months, the average sentence was 18.78 months, with a standard deviation of 9.11.  in the high anchor condition of 34 months, the average sentence was 28.70 months, with a standard deviation of 6.53.

CT point: True experiment, cause and effect relationship able to be drawn, small sample size, lack of generalizability.

Bechara

Topic: Biases in Thinking & Decision Making:

Content: Dual processing model/thinking and decision making

Trigger: Gambling card game, ventro-medial prefrontal cortex damage, learn from our mistakes, long term advantages

Aim: The researchers compared the decisions made by 17 healthy controls and 8 patients with lesions in their vmPFCs during the Iowa Gambling Task.

Procedure: To summarize the paradigm, there are four decks and participants select a card from one of the four decks. They do this for 100 trials. They win or lose money based on their decisions. What they don’t know from the start is that two of the decks have a high initial reward but high long-term risk factor (Decks B and D in the diagram below), whereas two decks have low initial risk and low reward. But actually, in the long run, the low risk and low reward decks are more advantageous because they will result in winning more money because they will lose less in the long-run.

It usually takes participants about 20 or 30 trials before they can realize the pattern and healthy controls typically opt for the “safe” desks, using Deck A and C. In other words, they are able to resist the initial temptation of going for the high reward decks, because they can see that in the long-term this is a bad choice; they are using system two processing of the information to make this decision because they can think through the consequences of that decision.

Findings: the results of this study showed the same trend: healthy participants were able to slowly move away from the disadvantageous decks (B and D) and chose more from the advantageous decks that had low initial reward but higher long-term gains (A and C).

The vmPFC lesion participants, however, did not demonstrate this same shift in behaviour. They continued to choose from the disadvantageous decks, regardless of the negative consequences.

CT point: