Cog Psych: Studies Flashcards
Murdock
1962
Aim: To see how the recall of lists of words related to the serial position curve:
Method: 16 particiapnts were presented with a list of 20 words at the rate of 1 word per second. Once they had heard all 20 words, they were asked to recall as many words from the list as they could remember, in any order. This is called free-recall. They were given 90 seconds to recall the words. The test was repeated with the same particiapnts 80 times over a few days. A different list was used each time.
Results: THe words at the end of the list were recalled first and very well. Words from the beginning were recalled next and quite well. Words from the middle of the list were not recalled very well at all. Murdock displayed these results in a graph called te serial position curve.
Conclusion: Primary effect. Recency effect. Middle words not good because in neither long term or short term store.
These results have been used to support the idea that there are 3 separate stores for information.
Branford and Johnson
1972
Aim: To investigate the role of schemas in our understanding and recall of information
Method: Bransford and Johnson made participants listen to quite a long speech under three different experimental conditions as follows:
1. No title condition – just hear paragraph itself
2. Title before condition – then hear paragraph
3. Title after – told title after hearing paragraph
Participants were then asked to indicate how easy it was to understand and to recall as much from it as possible. If they could not recall it word for word they should recall as many of the main ideas as possible.
Results: Of the 18 ideas the paragraph contained, participants recalled on average:
• No title condition – just heard paragraph itself (2.8 ideas)
• Title before condition – then heard paragraph (5.8 ideas)
• Title after – told title after heard paragraph (2.6 ideas)
Conclusions
The what-the-paragraph-is–about information given in the ‘title before’ condition seems to have activated the schematic knowledge about what is involved in washing clothes during the encoding stage. This information helped to disambiguate the paragraph so when hearing the first sentence (the procedure is quite simple….) participants had instantly began to start forming in their mind a mental image of what was happening and so schemas helped their understanding and recall. If they heard the title after, they had already forgotten all the information and so were less likely to recall the information. Obviously the ‘no title condition’ they had no clue! In conclusion, schemas improve comprehension and memory.
Evans
2003
Aim: To investigate the evidence for dual-process accounts of reasoning
Method: They investigated this with three examples chosen as illustrations. One of these was the wason card selection task, which provides evidence for dual-process accounts of reasoning because the task is so sensitive to the content of the task and the context in which it is presented. Many researchers investigating dual-processing have used it.
Wason developed this task to demonstrate the difficulties when heuristics interfere with abstract reasoning. Participants were presented with 4 cards, showing one side only (A,D,3,7). They were told that every card had a letter on one side and a number on the other side. Then they were given 2 conditions.
Condition 1= “If there is an A on one side of the card then there is a 3 on the other side”. They were asked which of the cards they needed to turn over in order to find out whether this rule was true or false. The answer was A and 7
Condition 2= “If there is an A on one side of the card then there is not a 3 on the other side of the card”. They were asked now which of they cards they needed to turn over to find out whether the rule was true or false. The answer was now A and 3.
Results: Most participants replied ‘A and 3’ or ‘only A’. They ignored the important of not finding an A on the back of the 7 and showed a matching bias (choosing cards mentioned in the statement). Participants sometimes chose an irrelevant card, such as 3 because they simply chose cards that patched the propositions or they may have interpreted the rule as an example of “if and only if”. In many studies only between 10-20% of participants got the right answer. In condition 2: Participants found this much easier, and most got it correct.
Thematic Task (Griggs and Cox, 1982)
Griggs and Cox investigated if context and content would reduce the number of errors made, In a realistic version of the first task, the information is given context and so becomes thematic rather than abstract.
Again the task had 4 cards (drinking beer, drinking coke, 22 years of age, 16 years of age)
Participants were told that they were police officers observing people drinking in a bar, and ‘if a person is drinking beer, then that person must be over 18 years of age’. They were then asked which of the asked which of the cards they needed to turn over to ensure that all beer drinkers were 18 or older (the correct answer was drinking beer, and 18 years of age)
Results: Most participants got the correct answer.
Conclusion. Performance on the abstract task is strongly affected by a system 1 heuristic, the matching bias. This can be demonstrated by introducing negative r components into the conditional statement. There is a strong tendency to choose matching cards mentioned in the statement, regardless of their logical status. Here, system 1 overrides system 2.
Landry and Bartling
2011
Aim: To investigate if articulatory suppression would influence recall of a written list of phonologically dissimilar letters in serial recall
Procedure. The participants consisted of 34 undergraduate psych students. The researchers used independent measures design. The participants were tested individually. In the experimental group, participants first saw a list of letters that they had to recall while saying the numbers 1 and 2 at a rate of two number per second (this is an articulatory suppression task). The control group saw the list of letters but did not carry out the articulatory suppression task.
There were ten lists each consisting of a series of 8 letters randomly constructed from the letters F,K,L,M,R,X,Q. These letters were chosen because they dont sound similar. The experimenter presented one letter series at a time. The participants had an answer sheet with 7 blanks that they would have to fill in.
In the control group, the participants were shown a list for 5 seconds, before waiting 5 seconds and then writing the letters down onto the sheet. In the experimental group, participants received instructions to repeatedly say the numbers 1 and 2 at a rate of two numbers per second from the time of presentation of the list until the time they filled the answer sheet. Both groups did this 10 times. Each trial was scored for accuracy of recall. The trial was scored as correct if the letters were in the correct position. The experimenter then calculated the average percent correct recall for both groups.
Results: Results showed that the scores from the experimental group were much lower than the scores from the control group. THe mean percent of accurate recall in the control group was 76% compared to 45% in the experimental group.
The results supported the experimental hypothesis. The results were also inline with the WMM theory as articulatory suppression is preventing rehearsal in the phonological loop because of overload.
Loftus and Palmer
1974
Aim: To investigate how information provided after an event had occurred influenced the memory of a witness for that event. in this case, the information given was a change in wording of a critical question.
Method: Two laboratory experiments were used for two segments of the study, each adopting an independent measures design. The researchers used an oppurtunity sample of 45 college students and 150 participants for the second.
In experiment 1, participants were shown seven 5-30 second film clips of traffic accidents. The clips were excerpts from safety films made for driver education. After each film they filled a questionnaire about what they had seen. They were also asked some questions about the accident. The critical question was “about how fast were the cars going when they HIT eachother?” Different conditions were used where the verb was changed to smashed, collided, bumped, hit, and contacted. Participants had to estimate the speed in miles per hour.
In experiment two, 150 participants were divided into 3 groups. All participants watched a one-minute film on a multiple-car accident. They then answered some questions about the film. The critical questions was ‘how fast were the cars going when they HIT eachother?’ The verb was changed to smashed in the comparison group. The control group was not asked to estimate the speed. The particiapnts were asked to return a week later. They were not shown the film again but they were asked several questions about the accident in the film. The critical question was, ‘did you see any broken glass?’, and they had to answer yes or no. The questions was placed in a random position on each question paper. Note the video did not have any broken glass.
Results: Experiment 1 found that when the question had the word shamed or collided, speed estimates were higher than for other words used. For smashed it was 40.8mph and for collided 39.3mph, while for contacted the estime was 31.8mph.
Experiment 2 found that the words smashed which implied a more forceful impact dew more than twice as many yes réponses as when the word hut was used and as compared with the control group.
Conclusion: Experiment 1 concluded that the speed estime was moderated by the verb used to describe the intensity of the crash. The greater the intensity conveyed by the word, the higher the speed estimate to match it.
Experiment 2 concluded that the estimates of the presence of glass increased with the intensity of the verb used to describe the crash.
Branstrom
2006
Aim: To examine the association between different risk perceptions, sun-related behaviour, readiness to change and optimism bias.
Method: Structured interview. The sampling technique was oppurtunity sampling and there were a total of 722 participants who were selected as they were visitors of mobile skin cancer screening units in Sweden.
Procedure: The participants answered two questions about their sunbathing habits: ‘how often do u spend time in the sun during the summer’ and ‘how often do u sunbathe during the summer with the intention to get a tan’. The response alternatives were ‘very often’, ‘rather often’, ‘sometimes’, ‘seldom’ and ‘never’. There was also a question regarding the personal risk of developing skin cancer with 5 response alternatives. very high, rather high, neither high nor low, rather low, and very low.
Results: Showed that participants in this study underestimated skin cancer incidence in the population and the impact of skin cancer on general healthy. 90% of both men and women of all aged underestimated the incidence of skin cancer in the population. 85% of the sample did not intend to stop sunbathing. Also, men seemed to be more optimistic about their chances of not getting skin cancer even though they are more likely than women to be diagnosed with a malignant skin tumor.
Brown and Kulik
1977
Aim: To investigate the determinants of flashbulb memories about assassinations, highly newsworthy events and personally significant events.
Method: Correlational data; based on a questionnaire centered around 10 very unexpected or novel events.
Participants: 40 white americans and 40 black americans, aged 20-60
Procedure: Participants filled out a questionnaire that was centered around 10 events. 9 of the events involved political figures (mostly assassinations) and the other event was a personal one that was unexpected and shocking. Participants were asked to write a free recall of circumstances in which they first received news of the event. They also rated each event on a five-point personal consequentiality scale and the frequency of rehearsal
Results: Black participants were more likely to have vivid, elaborate flashbulb memories about those national leaders who were most involved with US civil rights (such as MLK or Malcom X). Assassination these leaders had more personal consequentiality to black participants than to white participants. Occurrence of flashbulb memories correlated with ratings of personal consequentiality. Occurrence of flashbulb memories also correlated with frequency of overt rehearsal.
Conclusion: Results of the study match the predictions of the theory. They support the role of personal consequentiality in the formation of flashbulb memories. They also support the role of overt rehearsal in sustaining these memories.
Anderson and Pichert
1978
Aim: To investigate the influence of schemas on the retrieval of information from the long-term memory
Method: Experiment; mixed design
Participants; Introductory psychology students who were participating in order to fulfill a course requirement.
Procedure:
1. Participants were assigned either a homebuyer or a burglar perspective
2. They were then asked to read a text passage about a house where two boys were staying to skip school. The passage contained a total of 73 ideas, some of them being potentially interesting to a burglar, and some to a real estate agent.
3. Participants were given a filler task, then asked to reproduce the story in writing as accurately as possible.
4. Participants were given another filler task, then some were required to change the initial perspective (from a homebuyer to a burglar or vice versa). Other participants kept the initial perspective.
5. Participants had to reproduce the story one more time, without reading it again.
Results:
For the first recall, participants who had the burglar perspective recalled more burglar-relevant information and participants who had the homebuyer perspective recalled more homebuyer-relevant information.
Participants who had changed perspective recalled more information (an additional 7.1%) important to the second perspective but unimportant to the first. Note that they did not read the passage for the second time, so before the change of perspective this additional information had been encoded but not retrieved. Change of perspective influenced retrieval not encoding.
Conclusion:
Perspective in this situation is a type of schema. The study supports the idea that schemas influence the process of retrieval of already stored information from memory.
Yuille and Cutshall
Aim: to determine whether leading questions would affect memory of eyewitness at a real crime scene
Method: quasi experiment
Procedure: 13 eyewitnesses of an armed robbery were interviewed 4 months after the incident. Ppt’s were randomly assigned into 2 groups: leading questions or control. In the leading questions group ppt’s were asked if they saw “the” broken headlight on the getaway car whilst the control group was asked if they saw “a” broken headlight. Police reports of the incident indicated that there was in fact no broken headlight. Repeated with the question if ppt’s saw “the” yellow panel on a car or saw “a” yellow panel. The panel was blue.
Results: accuracy of witnesses compared to police reports was 79-84%, leading questions did not cause errors in memory with 10/13 ppt’s saying there was no broken headlight/did not notice the detail
Conclusion: suggests that memory is reliable, contradicts L+P’s study and suggests that a lack of emotional response to the video compared to that experienced by ppt’s in Y+C played a key role in influence of leading questions and therefore memory reliability
Peterson and Peterson
1959
Aim: To investigate the duration of short-term memory, and to test whether information which is not rehearsed is lost quickly from the short-term memory
Procedure: A lab experiment was conducted in which 24 participants had to recall trigrams (meaningless three-consonant syllables), such as ‘TGH’ or ‘CLS’. The trigrams were presented one at a time and had to be recalled after intervals of 3, 6, 9, 12, 15 or 18 seconds respectively for each trial. No two successive trigrams contained any of the same letters. After hearing a trigram, participants were asked to count backwards in threes or fours from a specified random number until they saw a red light appear (then they recalled the trigram). This is known as the brown peterson technique, and the purpose was to prevent rehearsal.
Findings: The results showed that the longer each student had to count backwards, the less well they were able to recall the trigram accurately.
— After 3 seconds, 80% of the trigrams were recalled correctly.
— After 6 seconds, this fell to 50%.
— After 18 seconds, less than 10% of the trigrams were recalled correctly.
Conclusion: Short-term memory has a limited duration (of about 18 seconds) when rehearsal is prevented.
McClure et al
2004
Aim: To use a delay-discounting experiment to examine the neural correlates of short-term and long-term preferences for monetary rewards
Hypothesis: The limbic system, which includes the hypothalamus, thalamus, hippocampus and amygdala, is involved in many of our emotions and motivations and will be activated mainly in choices involving an immediate outcome. The lateral prefrontal cortex and associated structures supporting higher cognitive functions will be activated by delayed choices.
Method: Participants made a series of choices between smaller/earlier and larger/later sums of money while their brains were scanned using fMRIs. The specific sums (ranging from 5 to 40 dollars) and times of availability (ranging from the day of the experiment to 6 weeks later) were varied across choices. Some of the decisions were more difficult to make than others.
At the end of the experiment, one of each participant’s choices was randomly selected to count and they received one of the rewards they had selected at the designated time of delivery.
Results: Parts of the limbic system associated with the midbrain dopamine system were more activated by decisions involving immediately available rewards. In contrast, regions of the lateral prefrontal cortex and posterior parietal cortex were activated more by the longer-tears options. The later and larger rewards resulted in the most activation of these regions.
Conclusion: The results suggest that human behaviour is often characterized by a competition between lower level impulsive and automatic processes and abstract reasoning and future planning.
Sharot et al
2007
Aim: To investigate the neural mechanism of flashbulb memory by comparing brain response to recollecting the 9/11 attack as compared to control events
Method: Quasi experiment.
Procedure: The study had 24 participants who had witnessed the 9/11 terrorist attacks in NYC, 2001. Three years after the attacks, the participants were asked to retrieve memories of that day as well as memories of personally selected control events from 2001. Participants were split in two groups, the Downtown group (they had been in Downtown Manhattan, close to the World Trade Centre at the time of the attack). The midtown group (they were a few miles away from the place of attack). The participants were places in an fMRI scanner, and saw a series of 60 cue words, either “summer” or “September”. On seeing the word “September” they had to provide a memory related to the terrorist attack. On seeing the word “summer” they had to provide an autobiographical memory from the preceding summer of 2001.
Results:
- Selective activation of the left amygdala occurred when participants were recalling events from 9/11, but not control events.
- The rates of this selective activation was different between the two groups. 83% of the downtown group displayed it but only 40% of participants from the midtown group displayed it.
- During 9/11 trials, the downtown group showed high amygdala activation than the midtown group, but there was no difference across groups for summer trials.
- Selective activation of the left amygdala correlated with the proximity of the participant to the WTC during the attacks (r=0.45)
Conclusion: It was concluded that selective activation of the left amygdala may be the neural mechanism of FBM. The pattern of results confirms that activation is higher when the participant was closer to the place of the attack (the event is more personally consequential).
Rosser et al
Sanchez
2012
Aim: To investigate how transferable the effects of playing video games are to to wider domains such as science learning.
Method: Lab experiment, independent measures design
Participants: 60 university students
Procedure: Participants were randomly divided into two groups:
— The spatial training group played a first-person shooter game (Halo)
— The non-spatial training group played a verbal game involving combining letters to form words (Word Whomp)
After playing their allocated game, participants read a complex text about plate tectonics that contained 3,500 word with no illustrations. It described a theoretical model of volcanic eruptions. After reading, participants were required to write an essay. Independent scorers read the essay and assessed the extent to which it demonstrated understand of the important concepts of plate tectonics.
Results: Participants who played a FPS achieved higher scores on the essay- these participants showed better understanding of plate tectonics.
Conclusion: Reading about a model of plate tectonics without illustrations requires one to encode verbal information and translate it into abstract spatial representations. Although this is somewhat different from what is required when playing a FPS, this research demonstrates that the skills acquired in the game are to some extent, generalizable to wider domains.
Gerardi et al
2008
Aim: To evaluate the effectiveness of virtual reality exposure using a virtual Iraq programme for treatment of PTSD in an Iraq war veteran.
Procedure: The participant was a 29 year old male who had seen 10 years’ service that included a year in Iraq. 6 months after his return he reported the symptoms of PTSD: intrusive traumatic memories, poor concentration, difficulty driving, mood irritability, and sleep disturbance with ‘cold sweats’. These met the DSM-IV requirements for PTSD. He completed a series of self-report questionnaires and scales regarding his mood, including anxiety and depression inventories. The memory of one particularly traumatic occurrence was identified as the primary trauma memory which was most distressing and intrusive.
During the weekly 90-minute VRE sessions (total of 4) the participant was exposed to 2 repetitions of his trauma memory, increasing in intensity with each session, and he reported his feelings and reactions after each sessions, including his Subjective Units of Distress ratings, between 1 and 100.
Results: The Clinician Administered PTSD scale (CAPS) score decreased significantly, by 56%, from a total score of 106 (extreme range) to a total score of 45 (moderate range). The PTSD Symptom Scale Self-Report score decreased significantly from a total of 35 to 10, which corresponded to the participant reporting a substantial decrease in the symptoms of his PTSD.
Conclusion: The veteran demonstrated improvement in PTSD symptoms as indicated by changes in scores on the CAPS and the PSS-R between before and after the treatment. Therefore, the VRE reduced his anxiety by reducing his distressing symptoms of PTSD.
