(AQA A) AS Psychology
Unit 1: PSYA1 – Cognitive Psychology, Developmental Psychology and Research Methods
Key Study Title Relates to:
Miller (1956) Capacity of STM
Baddeley (1966) Semantic Encoding in LTM
Conrad (1964) Acoustic Encoding in STM
Peterson & Peterson (1959) Duration of STM
Bahrick (1975) Duration of LTM
Loftus et al (1978) Misleading information
List (1986) Factors affecting accuracy of Eyewitness testimony (EWT)
Poole and Lindsay (2001) Factors affecting accuracy of Eyewitness testimony (EWT) – Age of witness
Fisher et al (1989) The use of the cognitive interview
Key study Title Relates to:
Ainsworth and Bell (1970) Types of attachment
Schaffer and Emerson (1964) Development of attachment
Harlow (1959) Learning theory of attachment
Bowlby (1944) Disruption of attachment
Hodges and Tizard (1989) Failure to form attachment and the effects of institutionalisation.
Rutter et al (2007) Failure to form attachment and the effects of institutionalisation.
Takahashi (1990) Cultural variations in attachment
Van Ijzendoorn and Kroonenberg (1988) Cultural variations in attachment
Andersson (1992) Implications of research into attachment and day care for child care practices.
Belsky and Rovine (1988)
Violata and Russell (1994)
NICHD report (2001)
The negative impact of day care on children’s social development (including peer relations and aggression).
Schweinhart et al (1993)
Creps and Vernon-Feagans (1999)
Vandell et al (1988)
The positive impact of day care on children’s social development (including peer relations and aggression).
Capacity in STM
Miller (1956)
Why are there so many things that come in sevens – such as seven wonders of the world, seven deadly sins, seven primary colours, seven notes of the musical scale, and seven days of the week?
Miller (1956) reviewed psychological research to see what had been discovered. Investigations into
various cognitive abilities have found that people can easily distinguish three musical tones, but when they asked to distinguish between five or more tones they become progressively more confused. If research participants are shown an arrangement of dots, flashed onto a screen, they
can count five or six of them easily. More than that number and accuracy deteriorates. Such findings suggest that our span of absolute judgement (e.g. distinguishing musical tones) and of immediate memory (e.g. counting dots) is for about five or six items. This would lead us to expect that, if you
have to remember a string of letters, seven letters might be the maximum that could be held in short‐term memory. But what if the letters were C‐A‐T‐W‐A‐L‐L? In this case the seven letters make two chunks of data (“CAT” and “WALL”). All words consist of bits of information – in the case of
“catwall” there are seven bits altogether, but there are only two chunks of information. If memory was limited by “bits” of information it could handle, then we can predict that it would be possible to remember twice as many five‐letter words as ten‐letter ones. Miller found that this wasn’t true.
Research has demonstrated that people can remember about seven words, no matter how many bits of information are in the word. It is the chunks of data that limit memory. Miller called chunking “the very lifeblood of the thought processes”. It improves the capacity of memory, although it may
reduce accuracy.
Evaluation of Miller (1956)
This research has useful applications. For example, phone numbers are chunked to make them easier to remember when making a phone call.
However, later research didn’t completely confirm Miller’s conclusion. For example, Simon (1974)
found that the number of bits in a chunk did have an effect on memory. Participants in his study had a shorter span for larger chunks such as eight‐word phrases, than for smaller chunks such as one‐syllable words. Therefore, immediate memory span is related to chunking but the number of chunks
remembered depends how big the chunks are!
Some psychologists, such as Case (1974), have used the idea of chunking to explain how children become capable of more complex mental tasks as they get
older. Case suggests that M‐space (which is roughly equivalent to STM) is used to hold information required while you are thinking. The restricted size of
this space acts as a limit to cognitive processing. As one gets older the space increases a little, but more importantly we also become more efficient at using it.
An example of this would be playing chess. Inexperienced players have to hold the rules in M‐space while they are playing. As one becomes more
experienced these rules become more automatic, having been incorporated in higher‐order units – a
process akin to chunking. This form of chunking leaves more space in M‐space for mental activities.
Task: With a learning partner, find a strength and a weakness of Miller’s findings. (Remember he reviewed others’ work). Does the research into capacity of STM have ecological validity? Can it be applied to real life?
Semantic Encoding in LTM
Baddeley (1966)
The aim of this study was to explore the effects of acoustic and semantic encoding in STM and LTM.
In the STM study, participants were asked, immediately after presentation, to recall, in serial order, a list of five words taken from a pool of words in the following categories:
Acoustically similar words (e.g. man, mad, map)
Acoustically dissimilar words (e.g. pen, day ,few) Semantically similar words (e.g. great, big, large) Semantically dissimilar words (e.g. hot, old, late)
In the LTM study, each list of words was extended to ten and recall was tested after an interval of
20 minutes.
The findings were that words with similar sounds were much harder to recall using STM than words with dissimilar sounds. Similarity of meaning had only a very slight detrimental effect on STM. When participants were recalling from LTM, recall was much worse for semantically similar words
than for semantically dissimilar words. Recall from LTM was the same for acoustically similar and acoustically dissimilar words.
Baddeley concluded that STM relies heavily on acoustic encoding. LTM primarily makes use of semantic encoding.
Evaluation of Baddeley (1966)
The use of the experimental method allows a causal
link to be drawn between type of coding used in STM and LTM and the accuracy of recall.
The conclusions of this study may not reflect the
complexity of encoding. Evidence from other studies shows that, in certain circumstances, both STM and
LTM can use other forms of coding.
Acoustic encoding in STM
Conrad (1964)
If you have to remember something for a short time, such as a phone number, you probably repeat it over and over. You repeat it acoustically. What is interesting is that people do this whether they
heard the information (someone told you the number) or saw it (you looked it up in a phonebook). This suggests that short‐term memory may encode information acoustically.
Conrad (1964) investigated this by comparing performance with acoustically and visually presented data. He presented participants with six letters at a time, displaying each of them for 0.75 of a
second. The participants had to recall the letters in the order that they were presented. When the letters sounded alike, even though they were visually presented, errors were made in terms of sound confusions, for example, S was recalled instead of X.
Evaluation of Conrad (1964)
Later research (Posner, 1969) demonstrated that visual codes do in fact exist in STM, at least some of the time. In Posner’s experiment participants were shown two letters, where the second letter
was either identical to the first letter (e.g. AA), or the same but a different form (e.g. Aa), or different (e.g. AB). The letters were displayed one at a time, separated by a 2‐second interval. Participants had to say whether the letters were the same or different. Reaction time was longer for Aa than AA
which suggests that participants were processing the data visually rather than acoustically (A and a sound the same but look different)
Task: As an evaluation point, how do you think that a gadget like the iphone might affect a person’s STM? How might Conrad’s memory experiments be considered to be out‐of‐date?
Duration of STM
Peterson and Peterson (1959)
The aim of the experiment was to test how long STM lasts when rehearsal is prevented.
The participants were briefly shown a consonant trigram (i.e. 3 letters such as CPW or NGV). Participants were asked to count backwards in threes from a specified number to stop them
thinking about the letters. After intervals of 3, 6, 9, 12, 15 or 18 seconds, participants were asked to recall the original trigram. The procedure was repeated several times using different trigrams.
They found that participants were able to recall 80% of trigrams
after a 3‐second interval. Progressively fewer trigrams were recalled as the time intervals lengthened. After 18 seconds, fewer than 10% of the trigrams were recalled correctly.
Peterson and Peterson concluded that if rehearsal is prevented,
information vanishes rapidly from STM. Therefore, decay is the mechanism for forgetting in STM.
Evaluation of Peterson and Peterson (1959)
Trigrams are rather
artificial things to remember and may not reflect everyday
memory.
It is possible,
however, that interference from the counting task (not
merely decay) caused the poor recall.
The experimental method used in this study allows us to see
the (causal) effect of time passing (independent
variable) on recall (dependent variable).
Duration of LTM
Bahrick (1975)
The aim of this study was to establish the existence of a very long‐term memory (VLTM), and to see
whether there was any difference between recognition and recall.
For the procedures the investigators tracked down the graduates from a particular high school in America over a 50‐year period. 392 graduates were shown photographs from their high‐school yearbook. For each photo, participants were given a group of names and asked to select the name
that matched the person in the photo (recognition group). Another group of participants were simply asked to name the people in the photos without being given a list of possible names (recall group).
Bahrick found that in the name matching condition, participants were 90% correct even 14 years
after graduation. After 25 years, these participants were 80% accurate; after 34 years, 75% accurate and, even after 47 years, 60% accurate. The 2nd group who had to identify the photos without any name cues were not quite as successful. They were 60% accurate after 7 years, but the level of
accuracy had dropped to less than 20% after 47 years.
Bahrick concluded that people can remember certain types of information for almost a lifetime. The accuracy of VLTM is better when measured by recognition tests than by recall tests.
Leading Questions in Eyewitness Testimony (EWT)
Loftus and Palmer (1974)
The study’s general aim was to investigate the accuracy of memory after witnessing a car accident. In particular it was to see if leading questions distort the accuracy of an eyewitness’s immediate recall. People are notoriously poor at estimating speed of moving cars and therefore they might be
particularly receptive to any hints (leading questions). This experiment aimed to see if this is true.
Evaluation of Bahrick (1975) Unlike many memory experiments, this study used meaningful stimulus material (high‐school yearbooks) and tested people for memories from their own lives. It is unclear whether the drop‐off in accuracy after 47 years reflects the limits of duration or a more general decline in memory with age. TASK: With a learning partner, attempt to assess the methods of this study so that you can find two more evaluation points. Remember to explain and apply each point.
Many studies have been conducted on EWT, a number of them by Elizabeth Loftus. Here she worked with John Palmer to look at some of the ways that memory can be distorted. Elizabeth Loftus is a prolific researcher in EWT and carrying out some research by yourself may help to improve your skills on your examination. Current information on Loftus can be found on wikipedia: http://en.wikipedia.org/wiki/Elizabeth_Loftus
The procedures involved 45 students being shown 7 films of different traffic accidents. After each film the participants were given a questionnaire which asked them to describe the accident and
then answer a series of specific questions about it. There was one critical question: “About how fast were the cars going when they hit each other?”. One group of participants was given this question. The other four groups were given the verbs ‘smashed’, ‘collided’, ‘bumped’ or ‘contacted’ in place
of the word ‘hit’.
The mean speed estimate was calculated for each group, as shown in the table. The group given the word ‘smashed’ estimated a higher speed than the other groups (about 41mph). The group given the word ‘contacted’ estimated the lowest speed (about 32mph).
Loftus and Palmer concluded that the form of question can have a significant effect on a witness’s
answer. In other words, leading questions can affect the accuracy of memory. Such leading questions are an example of what psychologists call post‐event information – information given after the event which may alter memory. It is possible that such post‐event information causes the
information to be altered before it is stored so that memory is permanently affected. A second possible explanation is that the form of the question actually alters the participant’s memory representation of the accident, which leads them to produce a higher or lower estimate.
Evaluation of Loftus and Palmer (1974)
A laboratory experiment may not represent real life because
people don’t take the experiment seriously and/or they are not emotionally aroused as they would be in a real accident. Foster et al (1994) found that if participants thought they were watching a
real‐life robbery and that their responses would influence the trial, their identification of the robber was more accurate.
Emotional arousal may actually enhance the accuracy of memory, as Christianson and Hubinette (1993) found when they
interviewed 110 real witnesses to bank robberies. Those witnesses who had been threatened were more accurate in their recall and remembered more details than those who had been onlookers and
less emotionally aroused. This continued to be true even 15 months later.
Evaluation of Loftus and Palmer (1974)
In many experiments, the experimental design leads to certain
inevitable responses from participants. They might feel uncertain about what to do and how to behave, and would look for cues about what is expected of them. They would be especially receptive to
certain features of the experiment, such as leading questions. These features almost demand a particular response and thus these demand characteristics might explain the findings of Loftus and Palmer’s study.
Loftus and Palmer conducted a second experiment to see if memory was altered by post‐event information. A new set of participants was divided into three groups and shown a film of a car accident. Group 1 was given the verb ‘smashed’, group 2 the verb ‘hit’, and group 3 (the control group) was not given any question about the speed of the vehicles. The participants returned one week later and were asked 10 questions about the accident, including another critical question: ‘Did you see any broken glass?’ There was no broken glass in the film but, presumably, those who thought the car was travelling faster might expect that there would be broken glass. The findings are shown in the table on the previous page. 17% of participants in the smashed condition said that they had seen broken glass. This compared to 7% in the hit condition. Participants gave higher speed estimates in the ‘smashed’ condition, as before. They were also more likely to think they saw broken glass. This shows a significant effect of post‐event information on later recall of events.
Factors that influence the accuracy of EWT
Loftus (1979) identified the weapon focus effect. There were two conditions in this experiment. In both conditions
participants heard a discussion in an adjoining room. In condition 1 a man emerged holding a pen and with grease on his hands. In condition 2 the discussion was
rather more heated and a man emerged holding a paper knife covered in blood. When asked to identify the man from 50 photos, participants in condition 1 were 49%
accurate compared with 33% accuracy in condition 2. This suggests that the weapon may have distracted attention from the man and might explain why eyewitnesses
sometimes have poor recall for certain details of a crime.
Yuille and Cutshall (1986) interviewed 13 people who had witnessed an armed robbery in Canada. The interviews took place more than 4 months after the crime and
included two misleading questions. Despite these questions, the witnesses provided accurate recall that matched their initial detailed reports. This suggests that
post‐event information may not affect memory in real life. This study also shows that EWT can be very reliable.
Amount of time – the
longer the time for which the event was observed
Distance – the close the
witness is to the event.
Visibility – the clearer the
visibility.
Obstructions – few
obstructions between witness and event
Known – the more familiar
the person, the better the identification
Any reason to remember –
the more novel or emotionally important the
better.
Time – the shorter the time
between the event and the
recall, the better the memory.
Errors – the more
inaccurate parts of a
witness’s testimony are sown to be, the less reliable is the rest of their testimony.
Factors affecting accuracy of EWT – age of witness
Poole and Lindsay (2001)
Poole and Lindsay engaged children aged 3 to 8 in a science demonstration. The parents of the
children then read them a story, which contained some of the elements of the science demonstration but also included novel information. The children were then questioned about the science demonstration and it was found that they had incorporated much of the new information
(i.e. from the parents’ story) into their original memory. In another phase of the experiment, the children were asked to think very carefully about where they had got their information from (this is called source monitoring) and some of the older children then revised their account of the science
demonstration and extracted the post‐event information. However, the younger children did not seem able to do this. This has important implications for measuring the accuracy of small children’s testimony since they seem very poor at source monitoring.
Methodological issues
This was an experiment but more difficult to eliminate extraneous variables than one using artificial stimuli in a highly controlled laboratory setting.
Investigators have to be particularly careful when using children, particularly those as young as 3 and
4 to make sure they understand instructions and that they are paying attention.
Ethical issues
There are particular factors to be taken into account when using young children who may not be able to give informed consent on their own behalf. Parents must give informed consent but, in this case, it was helpful that the parents were involved as well and so the children were with familiar
people and less susceptible to investigator effects.
Misleading information and the use of the cognitive interview
Fisher et al (1989)
The aim of this study was to further test the validity of the cognitive interview technique using a
field experiment. Precious research had mainly used laboratory experiments and the cognitive interview seemed highly effective in such studies.
16 experienced police inspectors from Miami, Florida, conducted two interviews on 47 witnesses or victims of shoplifting or mugging. Between the two interviews, 7 of the police officers were
trained in using the cognitive interview technique. The other 9 officers formed the control group (they received no further training). The researchers measured both the increase in facts elicited in the 2nd interview compared to the 1st, and the number of facts elicited by the police officers in the
cognitive interview group compared to the control group. The independent variable was the type of interview the police officers used on the 2nd interview (cognitive or standard) and the dependent variable was the number of accurately recalled facts produced by each of these techniques.
Results provided overwhelming support for the cognitive interviewing technique. The cognitive
interviewers obtained 47% more facts relating to matters already examined, whereas there was no gain from the 2nd interview for the control group.
Cognitive interviews are a useful technique for improving EWT when compared to a standard interviewing technique. This seems to occur
both in a laboratory and more realistic field experiments.
The officers in the control group were aware that they
were not being given any extra interview training and this might have affected
their motivation levels. It may have been this factor that led to the difference
in recall accuracy between the experimental and
control groups
Evaluation of Fisher et al (1989)
Practical problems involving application of cognitive interviewing: some research has
suggested problems with cognitive interviews. Memon et al (1994) failed to find an
improvement using a cognitive interview technique when used by police officers. In their
study, 38 experienced police officers were trained for 4 hours on general interviewing
techniques. Half of the police officers were then trained in cognitive interviewing
techniques. Immediately after this, the police officers were asked to interview witnesses of a
staged event (a simulated armed robbery in the parking lot of the police training school a few
hours earlier). The results showed no benefits of cognitive interviewing over standard
interviewing in terms of the number of correct answers or the number of incorrect answers
provided by the witnesses. Moreover, it appeared as though the cognitive interviewing
training had little effect on the interview procedures used by the police officers, so perhaps
the lack of any effect may have been due to either the training or a reluctance on the part of
the officers to fully implement the training.
Limited use by the police: there are concerns among the police that the use of the ‘change of
perspective’ mnemonic may mislead witnesses into thinking that they are being asked to
speculate on the event they witnessed. After all, no one can be certain what another person
saw. Due to worries such as these, this particular mnemonic is less frequently used in
practice (Memon et al, 1993).
Experimental Method Definition of a Field experiment Example of a Field experiment Strengths of a Field experiment
Weaknesses of a Field experiment
Research Methods – Methods and Techniques
Experimental Method Definition of a Laboratory experiment Example of a Laboratory experiment Strengths of a Laboratory experiment
Weaknesses of a Laboratory experiment
Experimental Method Definition of a Natural/Quasi experiment Example of a Natural/Quasi experiment Strengths of a Natural/Quasi experiment
Weaknesses of a Natural/Quasi experiment
Use this space to draw your scatter graphs:
Correlational Analysis Definition of Correlation Example of Correlation Strengths of Correlation
Weaknesses of Correlation
What is a Correlation Coefficient? For the following coefficients, explain the type (e.g. positive or negative) and strength (e.g. strong or weak) of the correlation.
+0.88 ‐0.35 ‐0.99 +0.55 +0.21 ‐0.65
Illustrate all 6 correlation coefficients using scatter graphs
Questionnaires Opinion Surveys Definition of an opinion survey Example of an opinion survey Strengths of an opinion survey
Weaknesses of an opinion survey
Psychological Tests
Definition of a Psychological test
Example of a Psychological test
Strengths of a Psychological test
Weaknesses of a Psychological test
Case Studies Definition of a Case Study Example of a Case Study Strengths of a Case Study
Weaknesses of a Case Study
Interviews Definition of a Structured Interview Example of a Structured Interview Strengths of a Structured Interview
Weaknesses of a Structured Interview
Definition of a Semi‐Structured Interview Example of a Semi‐Structured Interview Strengths of a Semi‐Structured Interview
Weaknesses of a Semi‐Structured Interview
Definition of a Clinical Interview Example of a Clinical Interview Strengths of a Clinical Interview
Weaknesses of a Clinical Interview
Definition of an Unstructured Interview Example of an Unstructured Interview Strengths of an Unstructured Interview
Weaknesses of an Unstructured Interview
Observational method Definition of Controlled Observation Example of a Controlled Observation Strengths of a Controlled Observation
Weaknesses of a Controlled Observation
Definition of a Naturalistic Observation (Obs) Example of a Naturalistic Obs Strengths of a Naturalistic Obs
Weaknesses of a Naturalistic Obs
Definition of a Participant Observation Strengths of a Participant Observation
Example of a Participant Observation
Weaknesses of a Participant Observation
Research Methods – Investigation Design
What is a Variable? What is an Operationalised Variable? What is an Independent Variable? What is a Dependent Variable?
What is a Hypothesis? What is a Directional (1‐tailed) hypothesis? What is a Non‐Directional (2‐tailed) hypothesis? What is a Correlational hypothesis? What is a Null hypothesis?
What is an Aim? Give an example of an Aim
What is an extraneous (confounding) variable?
Task: Write an example of: 1. A directional hypothesis 2. A non‐directional hypothesis 3. A correlational hypothesis 4. A null hypothesis Label the IV and DV in each hypothesis.
Examples of Hypotheses:
What is a Repeated Measures design? What is an Independent Measures design? What is a Matched Pairs design?
Strengths of Repeated Measures design
Weaknesses of Repeated Measures design
Strengths of Independent Measures design
Weaknesses of Independent Measures design
Strengths of Matched Pairs design
Weaknesses of Matched Pairs design
What is Sampling? What is Random Sampling? What is Opportunity Sampling? What is Self‐Selecting Sampling? What is Stratified Sampling?
Strength of Random Sampling
Weakness of Random Sampling
Strength of Opportunity Sampling
Weakness of Opportunity Sampling
Strength of Self‐Selecting Sampling
Weakness of Self‐Selecting Sampling
Strength of Stratified Sampling
Weakness of Stratified Sampling
Definition of Face validity Definition of Concurrent validity Definition of Predictive validity
What is a situational variable? How can you control a situational variable? What is a participant variable? How can you control a participant variable?
What is reliability? What is validity? Definition of internal validity Definition of external validity
British Psychological Society (BPS) guidelines for research with human participants http://www.bps.org.uk/the‐society/code‐of‐conduct/ethical‐principles‐for‐conducting‐research‐with‐human‐participants.cfm#principles Consent Deception Debriefing Withdrawal from investigation Confidentiality Protection of participants Observational research Giving advice Colleagues Colleagues
Dealing with deception Debriefing: Retrospective informed consent:
Dealing with protection of participants Right to withdraw: Terminating research: Debriefing:
Dealing with informed consent Prior general consent: Presumptive consent: Children as participants:
What is qualitative data? Give an example of qualitative data: What is quantitative data? Give an example of quantitative data
Measure of central tendency What is the mean? What is the median? What is the mode?
Strength of the mean:
Weakness of the mean:
Strength of the median:
Weakness of the median:
Strength of the mode:
Weakness of the mode:
Research Methods – Data analysis and presentation
Measures of dispersion What is the range? When should it be used? Strength of the range:
Weakness of the range:
Measures of dispersion What is the standard deviation? When should it be used? Strength of the standard deviation:
Weakness of the standard deviation:
What is content analysis? Give an example of content analysis
What is pure qualitative analysis? Give an example of pure qualitative analysis
What are the features of a histogram? Draw an example of a histogram:
What are the features of a bar chart? Draw an example of a bar chart:
What are the features of scattergram? Draw an example of a scattergram: