Paper 1 Psychology the Biological Approach (ERQ)

Question 1

Maguire

Answer 1

Aim: To investigate whether the brains of London taxi drivers would somehow differ due to their extensive knowledge of the city and their many years behind the wheel
Participants: 16 right-handed male London taxi drivers, all of whom had passed the ‘knowledge test’ and had their licence for at least 1.5 years. **50 right-handed male non-taxi drivers **

Procedure:
- The study compared the MRI scans of the taxi drivers, non-taxi drivers, and a database of MRI scans (for control) using voxel based morphometric and pixel counting in order **to measure both the neural density and the area of regions of the brain **
- The experiment was a single-blind study where the researcher would be blind to what MRI scans they were analysing
- The researchers were also looking **to see whether the amount of years spent as a London-taxi driver had a correlation with the anatomy of the brain **

Results:
- Pixel counting revealed that the area of the posterior hippocampi of the taxi drivers was significantly larger than that of the non-taxi drivers, however, the anterior hippocampi was significantly smaller
- Voxel Based Morphometry then also revealed that there was a **correlation between the amount of years spent as a long taxi driver and the neural density of the posterior hippocampi **

Note:
- The posteriur hippocampus is associated with spatial memory and navigation such as the formation and recalling of cognitive maps, and storing spatial information (explains its growth)
- The anterior hippocampus is involved in emotional memory (the reduction in the anterior hippocampus points towards a trade-off where the enhancement of spatial capabilities leads to a decrease in other areas of the brain)

Conclusion: The researchers had argued that the results of the study revealed that the hippocampus may be able to respond to environmental stimuli

Evaluation:
1. Strengths:
- Single-blind study reduced researcher bias
- No variables were manipulated
- Control group of MRI scan database was used

2. Weaknesses:
   - Correlational study only
   - Low sample size
   - Sampling bias with the majority of taxi drivers being male, reducing applicability/generalisation of the results

Question 2

H.M

Answer 2

Aim: To investigate the effects of brain surgery on the patient H.M
Participants: H.M

Procedure:
- IQ tests performed on H.M
- Interviews with family members and H.M
- Cognitive tasks such as memory recall and learning tasks were performed
- Observations on H.M
- MRI scan of H.M’s brain

Results:
- H.M could no longer acquire new** episodic (memory of events) **or semantic memories (general knowledge). This suggests that H.M was incapable of transferring short-term memory to long-term memory
- H.M was able to draw a floor plan of his house and still recognise his home, which suggests that his ability for cognitive mapping was still intact, and that this form of memory is encoded separately from episodic and semantic memory
- H.M still had **working memory **as he was able to maintain conversations which require knowledge of things recently said, and was able to recall values of numbers with repeated and extensive rehearsal. It should be noted that when H.M stopped rehearsing the number values, he would forget it.
- H.M still had procedural memory as he could mow the lawn and even improve in tasks he had never performed prior to his surgery such as reverse mirror drawing. But though he could improve in new skills, he would not remember learning or practicing them.
- Through an MRI scan, it was revealed that H.M’s temporal lobe and his **hippocampus **were destroyed as a result of the surgery

Conclusion: The hippocampus is responsible for the transfer of short-term memory to long-term memory as seen through H.M’s capabilities after having his hippocampus removed. Short-term memory however is believed to be stored separately from the hippocampus as H.M was still able to hold information in his short-term memory with rehearsal

Evaluation:
1. Strengths:
- Highly detailed case study
- Longitudinal study (over 50 years)
- Method triangulation
- High ecological validity as no variables were manipulated

2. Weaknesses:
   - Low replicability
   - Low generalisability

Question 3

Mcguagh and Cahill

Answer 3

Aim: To investigate the role of emotion in the formation of memory

Procedure:
- The participants were split into 2 groups.
- Each group would view 12 slides, which were accompanied by a story, however, in one group, the story would be** highly emotionally arousing**, and in the other, be a mundane story.
- After viewing the slides, the participants were asked to rate how emotional the story was from 1-10.
- After 2 weeks, the participants were then re-invited, where their memory on the details of both the slides and the story was tested.

• The researchers then did a follow-up study where the same procedure was followed except, this time, the participants would either be injected with propranolol or a placebo solution before viewing the slides
  Note: Propranolol is an antagonist which blocks the hormone adrenalin from binding to receptors on the amygdala which therefore prevents/inhibits the activation of the amygdala.

Results:
- In the original study, the participants in the condition with the emotionally arousing story had demonstrated a better memory recall than the group with the boring and mundane story
- Contrary, in the follow-up study, there were no observed differences seen amongst the two groups

Conclusion: The results of this study imply that the amygdala and the hormone adrenalin play a role in the formation of memory linked to emotional arousal

Evaluation:
1. Strengths:
- Cause-effect relationship (was an experiment)
- Standardised procedure = replicability

2. Weaknesses:
   - Low ecological validity
   - Reductionist approach, where the formation of memory linked to emotions is attributed to only to a biological process, disregarding the possibility of cognitive or social factors

Question 4

Draginski

Answer 4

Aim: To investigate whether learning a new skill would affect the brains of the participants
Participants: 24 participants aged 20-24, 21 females, 3 males

Procedure:
- Initially, an MRI scan was performed on all participants to generate scans which would serve as a baseline for grey matter density and brain structures **
- The participants were then allocated to one of two groups, the jugglers and the non-jugglers **
- The jugglers were told to practice a 3 ball cascading routine until they mastered it, at which point, they would notify the researchers and would undergo a **2nd MRI scan
- After the 2nd MRI scan, the participants were then told to completely stop practicing juggling for 3 months. At the end of that period they would have a 3rd MRI scan **
- Throughout the study, the non-jugglers served as a control group
- Using Voxel Based Morphometry (VBM) the researchers analysed the MRI scans of the participants to analyse for diffrences in grey-matter desnity

results:
- In the** baseline scans, there were no significant differences** seen in the brain structures and grey matter density amongst the jugglers and the non-jugglers
- In the 2nd scan however, it was seen that the **jugglers had a significantly larger increase in grey matter density in the mid temporal area of both hemispheres of the brain **(an area associated with visual memory) than compared to the non-jugglers
- It was then also revealed that after a 3-month period of not juggling any more for the non-jugglers, that the grey matter density for these areas of the brain would significantly decrease

Conclusion: This study provided evidence that the introduction and reduction of stimulus to the brain can cause neuralplacity and neural pruning

Evaluation:
1. Strengths:
- Pre-test/Post-test design to establish differences in neural density differences over time
- Control group
- Cause-effect relationship

2. Weaknesses:
   - As the study was a field experiment, it had low internal validity
   - Small participant size of 24
   - Sample was predominantly women

Question 5

Caspi et al.

Answer 5

Aim: To investigate whether there is a gene-environment interaction for the mutation of the serotonin transporter gene 5-HTT
Participants: 847 New Zealand 26-year-old whom have been previously assessed for mental health every other year until the age of 21

Procedure:
- Initially, the participants were split into 3 groups based on their serotonin transporter gene 5-HTT alleles
- Group 1: 2 short alleles, Group 2: 1 short and 1 long allele,
Group 3: 2 long alleles
- The participants were then asked to fill out a ‘stressful life-event’ questionnaire, which asked them on the frequency of different stressful events which had occurred between the age of 21 and 26.
- These events included topics such as relationships and finance
- The participants were also assessed for depression

Results:
- Participants with one or more short alleles of the serotonin transporter gene 5-HTT would display more symptoms of depression and suicidal idealisation in response to stressful life events when compared to participants with 2 long alleles
- This trend was more apparent with the more stressful life events

Conclusion: The inheritance of a short allele for the serotonin transporter gene 5-HTT in itself was not enough to warrant depression, however, would make an individual more dispositioned to displaying depressive symptoms when interacting with stressful life events

Evaluation:
1. Strengths
- No variables were manipulated
- Large sample of 847 participants
- Standardised questionnaire used

2. Weaknesses
   - Application limited only to 26 New Zealanders
   - correlational only
   - Self reporting bias
   - Questionnaires only give a limited scope of stressful life events experienced

Question 6

Antanova

Answer 6

Aim: To see if scopolamine effected hippocampal activity in the creation of spatial memory
Participants: 20 healthy adult males with a mean age of 28

Procedure:
- The experiment was a double-blind experiment, and the patients were** randomly assigned to one of two conditions**. The patients were either injected with scopolamine, or a placebo solution 70–90 minutes during the experiment
- In conducting the experiment, all participants were placed in an f-MRI machine which would scan the participant’s brain while they played a **virtual ‘Arena’ task **
- **The virtual ‘Arena’ task was designed to observe how well participants could create spatial memories **
- In the task, initially, the participants were shown the location of a ‘pole’ in a virtual arena. The screen would then go black for 30 seconds, where the participants were then asked to rehearse how to navigate to the pole in the arena.
- After the 30 seconds, the participants would then use their spatial memory to get to the pole
- This procedure was repeated 6 times, and before the experiment, the researchers accustomed the participants to navigating the virtual task with a joystick

• This experiment was a repeated measures design, having the same participants repeat the exact same experiment 3–4 weeks after the original experiment, however this time, given the opposite treatment they were administered in the original experiment

Results:
- Participants, when allocated to the group injected with scopolamine, would demonstrate significantly less hippocampal activity when compared to the placebo group
- Participants when allocated to the scopolamine condition also took longer time to navigate towards the pole

Conclusion: It appears that acetylcholine plays an important role in the formation of spatial memories

Evaluation:
1. Strengths:
- Repeated measured design eliminates individual differences affecting results
- Double-blind method procedure reduces researcher bias
- Standardised Procedure
- Controlled environment
- High internal validity

2. Weaknesses
   - Low sample size
   - Low generalisability with only male adults
   - Low ecological validity

Question 7

Zhou et al

Answer 7

Aim: To investigate the effects of AND and EST on heterosexual and homosexual men and women
Participants: **24 heterosexual men, 24 heterosexual women, 24 homosexual men, 24 homosexual women **

Procedure:
- All participants were presented with a point light motion task, where a series of dots moved in a manner to represent human motion
- The participants were tasked to observe the motion of the point light motion stick figure, and to identify its sex

• This task performed for 3 consecutive days at roughly the same time.
• Each day however, the participants would be continuously exposed to either a scent of AND mixed with cloves, a scent of EST mixed with cloves, or a scent of a controlled solution mixed with cloves
• The scents would be counterbalanced each day to minimize order effects

Results:
- Heterosexual females, and homosexual males, when exposed to AND, were found to more consistently identify the stick figure as masculine when compared to the control group. There was no effect of AND on heterosexual men, and homosexual females
- In contrast, when heterosexual males were exposed to EST, they would be more likely to identify the stick figure as feminine. There was no effect of EST however on homosexual females

Conclusions: It appears that the pheromones AND and EST may influence the sexual behaviour of humans

Evaluation:
1. Strengths
- Cause and effect relationship
- Counterbalanced, minimizes order effects such as systematic bias
- Lab experiment, controls environment
- Repeated measures control for participant variability

2. Weaknesses
   - Low ecological validity
   - Low sample size
   - Could still have order effects such as the fatigue effect or habituation effect

Question 8

Wedekind

Answer 8

Aim: To investigate whether one’s MHC type could influence mate choice
Participants: 44 males and 49 females who were students at one university in Switzerland. The males and females were chosen from separate courses to reduce the likelihood of already knowing each other

Procedure:
- Before the experiment had begun it was noted whether the women were taking oral contraceptives, and the MHC type of all participants was taken
- Men were asked to wear a shirt for 2 nights in a row, where during the day the shirt would be kept in an open plastic bag
- During this time period, the men were give perfume free detergent to wash their clothes and sheets, and perfume free soap for showering
- Men were also asked to refrain from activities such as smoking, drinking, eating spicy foods or engage in sexual activity.
- During this period, and leading up to the experiment, the women were asked to reduce the risk of activities which could result in sickness, and to use a nasal spray. This was done to attempt to improve their sense of odour.
- When the women would start their menstrual cycle after men had worn the shirts is when the test began
- Women were placed in a room with 7 boxes, with one t-shirt per box. The women had to smell the shirts through a ‘smelling hole’ and then rate the smell on a rank of pleasantness and sexiness
- 3 of the shirts would be from men of same MHC type, and 3 of the shirts would be from men of different MHC type. 1 shirt would be a control and would not have been worn by anyone.

Results:
- Women generally ranked shirts of different MHC type as being more pleasant than shirts of similar MHC type
- This trend was reversed when women would take oral contraceptives

Conclusion:
- It was concluded that one’s MHC type may indeed influence mate choice in humans

Evaluation
1. Strengths:
- High internal validity with lots of control
- The independent variable was naturally occurring and was not manipulated

2. Weaknesses:
   - High internal validity = low ecological validity
   - Low generalisability due to all participants coming from the same university and low participant number
   - Reductionist approach

Question 9

Rogers and Kesners

Answer 9

Aim: To investigate the role of acetylcholine in the formation of spatial memories
Participants: 30 Rats

Procedure:
- Before the experiment had begun, the rats were acclimated to a Hebbs-Williams maze until they were no longer scared of the new environment. This was done to reduce stress as a confounding variable in assessing the formation of spatial memories

• The rats were then randomly allocated to one of two conditions. The rats were either injected with scopolamine, or a saline solution (placebo) to the hippocampal area of the brain. (The placebo solution was used to reduce the influence of stress induced by receiving an injection as a confounding variable).
• The rats received these injections 10 minutes before running the experiment
• The rats then ran the maze and while doing so, the researchers analysed both their encoding and retrieval of spatial memories
• The encoding of spatial memories was analysed comparing the average amount of errors made on the first 5 trials of day 1, to the last 5 trials of day 1
• The retrieval of memories was analysed comparing the average amount of errors made on the first 5 trials of day 2, with the last 5 trials of day 1

Results
- The group injected with scopolamine took longer, and made more errors whilst learning the maze – that is, had a higher amount of average errors made on the last 5 trials of day 1 when compared to the saline solution group (placebo solution).
- There were no differences seen however when analysing the retrieval of spatial memories once they were formed

Conclusion: The results suggest that acetylcholine may play an important role in the formation of spatial memories

Evaluation:
1. Strengths
- Cause and effect relationship
- Reduced confounding variables

2. Weaknesses
   - Reductionist approach to what the formation of memory is (it’s not just limited to memorising the layout of a maze)
   - Though animals can serve as models for human behaviour, there are questions about the extent these findings can be genneralised to humans

Question 10

Meaney et al.

Answer 10

Aim: To investigate the effect of glucocorticoids on memory

Procedure:
- Meaney et al. was an animal study, which tested how elevated levels of the stress hormone, glucocorticoids, in rats in early life would influence their memory in the future

• To do this, the study used an independent samples design and allocated a group of newborn rats to one of two conditions
• The newborn rats would be handled by researchers for 3 weeks, from the day of their birth, to the time of their weaning
• During this time, for every day for 15 minutes, the researchers would take the newborn rats from their mothers and place them in a plastic box with a paper towl in it
• In the **experimental group, **during the time in the box, the researchers would brush the newborn rats in order to simulate the grooming performed by the mother rat. This was done to reduce glucocorticoid levels in these rats during this time of stress
• In the** control group,** the same procedure would be done however they would not be brushed/groomed during this time which would** result in an increased level of stress hormones, glucocorticoids**
• **To test the effects of the elevates stress hormones on the rats over their life times, ** the researchers would experiment the rats once more once they reached 2 years of age
• The rats would be placed into milky water with a platform, where the researchers would track both the route and duration of the rats towards the platform based off their previous memory gathered from previous trials in the solution

Results:
- It was seen that the rats in the control condition which had higher levels of adrenal glucocorticoids would take a more circuitous route towards the platform, indicating a reduction in their capabilities of memory when compared to the experimental group

• This can be explained by epigenetics. Rats in the experimental group, when brushed/groomed, would have a gene triggered which is responsible for the response to stressful events
• As glucocorticoids are associated with the reduction of neurons in the brain (specifically the hippocampus), the rats in the control condition without the gene responsible for stress response, would in turn, have higher glucocorticoids levels throughout their life, and this may have **led to the accelerated degradation of their memory ability **

Evaluation:
1. Strengths
- Cause effect relationship

2. Weaknesses
   - Can animal studies be generalised to humans?
   - Low ecological validity

Question 11

Weissman et al.

Answer 11

Aim: To study the potential genetic nature of Major Depressive Disorder (MDD)
Participants: **161 grandchildren, alongside their parents, and their grandparents **

Procedure:
- The study was longitudinal, and analysed **3 generations of participants ** over 20 years
- The original sample of participants (the 1st generation) were sourced from two areas. The depressed participants were sampled from an out-patient clinic, and the non-depressed participants would be sampled from the same local community.
- During this first period, the researchers would conduct 4 interviews with both the original patients, and their children (the 2nd generation)
- After this period, the children would then grow up and have children of their own, where the researchers then studied a 3rd generation
- The 3rd generation grandchildren of the original patients were analysed by one psychologist, and a child psychiatrist, who were blind to the family history of depression. Using researcher triangulation, the 3rd generation grandchildren were assessed for psychiatric disorders.

Results:
- It was seen that grandchildren with a family history of 2 generations of depression would have high rates of psychiatric disorders. By 12 years old, 59.2% of the grandchildren would show signs of a psychiatric disorder, which was most commonly an anxiety disorder
- It was further seen that grandchildren with both depressed parents and grandparents were at a higher risk of a mood disorder when compared to grandchildren which just depressed grandparents
- In addition, the severity of a parent’s depression was correlated with an increased rate of mood disorders in the grandchildren.

• In contrast, grandchildren with non-depressed grandparents but depressed parents would display no significant effect of parental depression on the grandchildren

Evaluation:
1. Strengths:
- Longitudinal
- Researcher triangulation to increase reliability
- Single-blind study by the psychologist and psychiatrist which reduces chance of researcher bias
- Large sample size
- High ecological validity as no variables were manipulated

2. Weaknesses:
   - Low internal validity with confounding variables such as the amount of time children would spend with either parents or grandparents
   - No cause effect relationship established
   - No genome responsible for MDD or mood disorders were found
   - Low generalisability as all participants were taken from the same local community
   - Reductionist approach as the development of depression or mood disorders was simply watered down to just a potential genetic influence instead of looking at the broader scope of potential cognitive or social cultural factors

Question 12

Newcomer et al.

Answer 12

Aim: To study whether increased levels of the stress hormone cortisol interfere with **verbal declarative memory **
Participants: students and employees from the Washington university medical centre

Procedure:
- Initially, participants were analysed by a physician, where they would be excluded from the sample if they were either pregnant, had a history of a mental illness or head trauma, or had previously suffered from an illness that was treated with medications containing cortisol.

• The participants were then matched for age and gender to one of 3 conditions
• In the 1st condition, the patients were given tablets with 160mg of cortisol to be taken once a day for 4 days
• In the 2nd condition, the patients were given tablets with 40mg of cortisol to be taken once a day for 4 days
• In the 3rd condition, the patients were given placebo tablets with no substance to be taken once a day for 4 days
• All participants were first asked to listen and recall a prose paragraph before taking the tablets (baseline of verbal declarative memory)
• After which, the participants were then tested for their verbal declarative memory one day after taking their tablets, and then again 4 days later after 4 consecutive days of taking their tablet
• There was a test again 6 days later to ensure no longer-term effects

Results:
- The participants who took the cortisol tablets with the highest amount of cortisol had showcased the worst performance on the memory task

Conclusion: The evidence of this study showcases that verbal declarative memory had a clear link with cortisol amount, and that higher levels of cortisol interfere with recall of prose passages

Evaluation:
1. Strengths:
- Matched pair design reduces individual variability effecting results
- Cause effect relationship seen
- Baseline removes the possible confounding variable of individual differences between groups.

2. Weaknesses:
   - Confounding variables in participant lives may have influenced individual stressors in the lives of the participants
   - Low ecological validity