Cognitive Processing Flashcards
HM Aim
In 1953, Scoville performed surgery on HM to cure him of his epileptic seizures. It is important to note that it was a surgical procedure, and only became a study once memory damage was noted.
MSM studies
HM|Glanzer and Cunitz (1966)
HM bg info
HM fell off his bike which caused sever epileptic seizures
HM method
During surgery, Scoville removed brain tissues from anterior two thirds of the hippocampus.
HM results
After the surgery, the seizures reduced, but HM suffered with amnesia for the rest of his life. HM lost ability to form new memories (anterograde amnesia) and also had partial retrograde amnesia - the inability to recall memories formed before the amnesia-inducing event. However, HM’s early childhood memories stayed intact and his IQ remained the same.
HM Conclusion
Thus, this study acts as evidence for STM and LTM being in different stores as HM demonstrated an inability to transfer information into LTM, although he could partially make short-term memories. Also maintained procedural memory. Suggests that hippocampus must be integral in transfer of memories from STM to LTM
HM strengths
- Case study - allows for the triangulation of
researcher, data and method - Longitudinal study- over 50 years
- Allows for the deeper, more detailed
research compared to the amount that
would have been able to be found had it
been a shorter snapshot study
- Allows for the deeper, more detailed
- Theoretical generalisability
- Can be used as a counter to lack off
generalisability - E.g. Creating a counter:
○ HM was quite “normal” and
“healthy.” Since all humans have
hippocampus, can theorise that if
all humans had their hippocampus
removed, they would experience
the same symptoms (not being able
to transfer from short to long term
memory)
- Can be used as a counter to lack off
- Qualitative data- rich, detailed
- Ecological validity - the situation occurred
naturally
HM weaknesses
- Possible researcher bias
- Retrospective study: Type of longitudinal case
study design in which all data are collected
after the fact (i.e. After HM’s operation)- Researchers had no knowledge of HM’s
abilities prior to operation
- Researchers had no knowledge of HM’s
- Case study –> population validity –> lowered
generalisability
HM EC
- Informed consent
- Deception
- Protection from harm
- Vulnerable patient
G&C aim
The aim of the study was to investigate serial position effect.
GC method
The study used a repeated measures design in which participants, 240 army-enlisted men, were required to memorise lists of words followed by a free-recall task. In the first condition, participants presented with recordings of 20-word lists consisting of common one-syllable nouns. Immediately after hearing the words they were required to do a free-recall task for two minutes. In the second condition, researchers introduced a delay between the end of the list and the start of recall. During the delay, participants engaged in a filler task: counting backwards from a given number for 30 seconds. The filler task was meant to prevent rehearsal.
GC results
The results of the trials in condition 1 clearly demonstrated serial position effect in both its aspects: participants were better at remembering words at the start of the list (primacy effect) and at the end of the list (recency effect), and this was not dependent on the number of repetitions of each word
In condition 2, the resulting data indicated that participants were still successful at recalling the words from the start of the list (primacy effect observed), but were no longer able to recall the words from the end of the list (recency effect disappeared)
GC conclusion
The researchers concluded that the first items on the list tend to get rehearsed more, moving to LTM which is unaffected by delay. Additionally, the last words on the list are not rehearsed as much, which is why they disappeared from the STM in the second condition. This shows that STM and LTM have separate mechanisms behind them.
GC strengths
Lab experiment
* High internal validity
○ Control
○ Replicable
○ Able to establish cause and effect
* Therefore generalisability
GC limitations
Low ecological validity and demand characteristics
The experiment was done in a lab which is an artificial environment, which may have caused the participants to show demand characteristics.
Sample bias
* All men in the sample were from the army - career may have affected their ability to memorise.
* Androcentric - only males were used for the experiment, meaning thee results are not generalizable to females
* Beta bias - assumes that the results can be directly applied to females as well, minimising the differences between them.
WMM studies
Landry and Bartling (2011)|KF - Shallice and Warrington (1970)
LB aim
To investigate if articulatory suppression would influence recall of a written list of phonologically dissimilar letters in serial recall.
LB method
The participants were psychology students who were randomly assigned to one of two conditions. In the experimental group, participants saw a list of letters, then had to recall them while speaking aloud (articulatory suppression task). In the control groups, the participants saw a list of letters, but had to recall without speaking aloud.
LB results
The results showed that the scores from the experimental group were much lower than those of the control group, meaning that the participants had a more difficult time recalling information.
LB conclusion
The data seems to support the prediction of the WMM that disruption of the phonological loop through the use of articulatory suppression results in less accurate working memory.
LB strengths
Lab experiment
* High internal validity
○ Control
○ Replicable
○ Able to establish cause and effect
○ reliable
LB limitations
Sample bias
Psychology students were used for the study and are not representative of the population
Low ecological validity
The study was an experiment conducted in a lab where the variables were highly controlled, meaning it does not model a realistic situation
Demand characteristics and social desirability effect
The psychology students may have predicted what the aim of the study was and behaved a certain way to achieve certain results. Furthermore, they may have wanted to be liked by the experimenters, thus showing SDE by demonstrating demand characteristics
Cultural bias
The experiment was done in the USA, meaning that the findings may not be applicable to other cultures
KF aim
To investigate the impact of brain damage on short-term memory.
KF method
A series of tests were done on patient KF who had suffered from brain damage due to a motorcycle accident. He was presented with information orally and then visually which he had to recall.
KF results
KF was able to remember visual information much better than verbal, and could still transfer information from STM to LTM.
KF conclusion
This supports the WMM because it shows that there are different stores for different kind of information. KF’s ability to recognise visual and auditory information, but not verbal supports the existence of different components for information.
KF strengths
Case study:
Since the research method was a case study, it was also longitudinal, which allowed researchers to be more precise in their investigation and findings. This also allowed the researchers to find patterns over time in the patient’s memory.
KF limitations
Case study
Since the research was only on one patient, it was difficult to generalise to the wider population.
Researcher bias
The researchers developed a relationship with KF due to the study being longitudinal, which may have influenced the results and gotten too involved because they had become emotionally attached.
KF EC
Since KF suffered from brain damage, it is difficult to know how well-informed he was about this study. He may not have completely understood what he was getting into, which is important as it is hard to be certain about whether or not he gave consent to the experiment.
schema theory studies
Brewer and Treyens|Loftus and Palmer
BT aim
To investigate the role of schema in encoding and retrieval of episodic memory.
BT method
The sample consisted of university psychology students. The participants had to sit in a room made to look life and office, in which there were typical objects as well as sever strange objects placed inside. Then the participants were taken out of the office and asked to recall the objects inside it.
BT results
When participants had to recall through writing or drawing, they were more likely to recall items which were congruent with their schemas, even if they weren’t actually in the office. Participants had a tendency to change the nature of the object to match their schema. Some participants also remembered certain objects incongruent with their schemas.
BT conclusion
The researchers concluded that schemas affect the reconstruction of memory shown by how the participants recalled objects that were typically in an office even if they weren’t present. Also, we have a tendency tor recall objects that don’t fit into our schemas because they stand out from what we expect to see.
BT strengths
High reliability
Due to its low ecological validity, the experiment is reliable because it is easily replicated due to standardised instructions and controlled variables.
BT weaknesses
Low ecological validity
The experiment was done in an artificial environment. This behaviour may not be applicable to other situations.
Demand characteristics
Psychology students were used. They may have shown demand characteristics because they knew what to expect from a psychology experiment.
Sample bias
Only university students were used for the experiment, meaning the sample was not representative of the population.
LPa aim
To investigate whether the use of leading questions would affect an eyewitness’s estimation of speed.
LPa method
45 students were divided into 5 groups. They were shown film recordings of traffic accidents after which they had to answer a questionnaire about it. There was one critical question in which the students were asked how fat the car was going during the accident. The word “accident” was changed to varying degrees of intensity i.e. “hit”, “collided”, “smashed”. The different words were used because they have different connotations which in turn triggers different schemas.
LPa results
The mean estimates of speed were highest in the ‘smashed’ condition (40.8 mph) and lowest in the ‘contacted’ group (31.8 mph),meaning the critical question where the words had a more intense connotation had a higher estimate of speed.
LPa conclusion
The researchers concluded that there were two interpretations of the findings. The first was response bias, wherein using a verb with higher intensity such as “smashed” biases the response to a higher estimate. The second in memory change, where the question may have cause the participant’s memory representation to change. For example, a verb of higher intensity such as “smashed” may have caused the subject to remember the memory as being more severe than it really was.
LPa strengths
Practical applications: adds to credibility of theory
* Proved that memory is not reliable
* In the court, while eye-witnesses can be brought in, their word alone can not be used as a means to persecute someone.
* Police should avoid asking leading questions
* High replicability * Control of variables * Standardisation of method
LPa weaknesses
- Artificial setting - lack of ecological validity
- Specific to loftus: they were her students
- Could have been demand characteristics
‘screw you’ effect - extraneous variable that could have happened if the student didn’t like her and hence wanted to ruin her experiment
- Could have been demand characteristics
TDM studies
Kahneman and Tversky|Alter et al
KT aim
To test people’s mental shortcuts and biases when making decisions.
KT method
The sample groups of 95 participants were given the following scenario: a certain town is served by either a larger hospital where about 45 babies are born each day, or a smaller hospital about 15 babies are born each day. While 50% of all babies are boys, the exact percentage varies from day to day. For one year, each hospital recorded the days on which more than 60 percent of the babies were boys. Which hospital do you think recorded more such days: the larger hospital, the smaller hospital, or both about the same (within 5% of each other). The researchers then recorded the participants responses.
KT results
The correct answer in the smaller hospital. However, most participants got this wrong and chose option three, presumably assuming that since the birth-rate is 50/50, the probability in this scenario would be too.
KT conclusion
Overall, Kahneman & Tversky clearly demonstrated how people will tend to use System One to come to a quick decision/conclusion, whilst simultaneously ignoring other important information that could be used by System Two thinking, to come to a more logical and rational decision. This study demonstrated how people tend to employ System One’s more intuitive and automatic thinking from the Dual Processing model when faced with probability scenarios, or situations where there’s potential for an information overload. `
KT strengths
- simplicity of the study allows for it to replicated easily, which helps to establish the reliability of the study’s results
- highly controlled true experiment which increases internal validity allowing results to be generalized
HOWEVER (heuristics point) this provides evidence for System 1
KT weaknesses
- demonstrate usage of heuristics in participants, offering a question that was cognitively undemanding
- Internal validity - participant variables should be considered it was not checked prior to the experiment if any participants had a prior background in statistics
Alter aim
To investigate how font affects thinking.
Alter method
40 Princeton students completed Cognitive Reflections Test (CRT). This test is made up of 3 questions, and measures whether people use fast thinking to answer the question (and get it wrong) or use slow thinking (and get it right). Half the students were given the CRT in an easy-to-read font, while the other half were given the CRT in a difficult-to-read font.
Alter results
Among students given the CRT easy font, only 10% of participants answered all three questions correctly, while among the students given the CRT in difficult font, 65% of participants were fully correct.
