Psychology SAQ Prep

Describe one study of neuroplasticity/ Explain one study of neuroplasticty making use of one study.

Maguire

1) Neuroplasticity - Neuroplasticity is the ability of the brain to rearrange the connections between its neurons. High levels of stimulation and numerous learning opportunities lead to dendritic branching that results to an increased neural density of neural connections and this is called dendritic and synaptic connection which is referred to as dendritic arborization. On the other hand, when one stops using a certain skill or applying certain knowledge for a considerable amount of time, the dendritic connections that had been made begin to die and this is referred to as neural pruning.

2) Aim- To see whether the brains of London taxi drivers would somehow be different as a result of the exceptional training, "the knowledge", they had to have in order to be certified.

Participants- 16 right-handed male London taxi drivers (experimental group).- They should have had a license for at least 1.5 years.

50 right-handed males who did not drive taxis were the control.

Range of ages.

Procedure-

MRI of the controls was taken from an MRI database.

The data from the MRI was measured using (VBM- Voxel-based Morphometry) and pixel counting.

VBM was used to measure the density of grey matter in the brain and pixel counting was used to calculate the area of the hippocampus.

3) Pixel counting revealed that the posterior hippocampus of taxi drivers was significantly larger relative to those of the control groups and the anterior hippocampus was significantly smaller. * Focus on this more VBM showed that the volume of the right posterior hippocampi correlated with the amount of time one spent as a taxi driver.

The hippocampus changes in response to environmental changes, and since it is involved when previous spacial information is used, the drivers with more experience had larger hippocampus.

Explain one study of localization of function of the brain

(Correlational )Maguire- Neuroplasticity, localization.

1. Brain localization is the theory that different parts of the brain are responsible for specific behaviors or certain functions. The main parts of the brain being the brain stem, cerebellum, cerebrum and the limivic system that comprises of the hippocampus, amygdala, hypothalamus e.t.c. which all have specific functions.

2) Aim- To see whether the brains of London taxi drivers would somehow be different as a result of the exceptional training, "the knowledge", they had to have in order to be certified.

Participants- 16 right - handed male London taxi drivers (experimental group).- They should have had a license for at least 1.5 years.

50 right - handed males who did not drive taxis were the control.

Range of ages.

Procedure-

MRI of the controls was taken from an MRI database.

The data from the MRI was measured using (VBM- Voxel- based Morphometry) and pixel counting.

VBM was used to measure the density of grey matter in the brain and pixel counting was used to calculate the area of the hippocampus.

3) Pixel counting revealed that the posterior hippocampus of taxi drivers was significantly larger relative to those of the control groups and the anterior hippocampus was significantly smaller. * Focus on this more VBM showed that the volume of the right posterior hippocampi correlated with the amount of time one spent as a taxi driver.

The posterior hippocampus is involved when previously learned spatial information is used and this is why the posterior hippocampus of the taxi drivers is greater than that of the control group.

Explain neuropruning using one study

Study Draganski.

1) Neural pruning refers to the process by which neurons and synaptic connections that are not frequently used are eliminated in order to increase efficiency of neural transmissions that are still in use. Neural pruning results from the lack of long term potentiation in the brain which is the process by which synapses are strengthened resulting to dendritic arborization which is an increase in neural density. Both neural pruning and dendritic arborization result to brain neuroplasticity, which is the ability of the brain to change its structure as the individual interacts with their environment.

2) Neural pruning is best illustrated by Draganski's study which involved

Participants

24 volunteer participants, 21 females and 3 males, between the ages of 20 and 24. All the participants were non - jugglers at the start of the

Procedure

study and Draganski took a base MRI of their grey matter and brain structure. He then divided them into a control group and experimental group. The experimental group was taught a juggling routine and they were asked to practice this routine and notify the researcher after they had mastered it. After mastering the routine, another MRI scan was taken of all the participants.

To analyse the scans, the researchers used voxel - based morphometry and found that the amount of grey matter in the mid - temporal area in both brain hemispheres of the jugglers was significantly greater than that of the non - jugglers. This area is associated with visual memory, indicating that juggling relies on visual memory hence dendritic arborization had occurred in the mid temporal area as the jugglers practiced their routine.

The participants were then asked to stop juggling and after three months, another MRI scan was taken. The researchers observed that the amount of grey matter in the experimental group had decreased but there was no change over time in the amount of grey matter observed in the control group.

3) This shows that after the jugglers stopped practicing their routine, the synaptic connections that had taken place in their mid - temporal area were eliminated as they were not used anymore and neural pruning had occurred.

Explain the role of one neurotransmitter in human behaviour, making use of one study.

Neurotransmitters- Troster and Beatty

1) The nerve cells, neurons, send electrochemical messages to the brain so that people can respond to stimuli, either from the environment or from internal changes in the body. The process by which the electrical message is sent is referred to as neurotransmission and the electrical impulse that travels along the body of the neuron is called an action potential. When an action potential travels down the body of the neuron, it releases neurotransmitters that are stored in the neuron's terminal buttons. The neurotransmitters are then released into the synapse. After crossing the synapse, the neurotransmitters fit into receptor sites. Neurotransmitters range from acetylcholine to dopamine, serotonin etc.

2) Study- Troster and Beatty

Aim - To investigate the role of acetylcholine in the formation and retrieval of memory.

Participants- 13 men between the ages of 31 to 59 with the mean age being 39.2. They were tested for both physical and mental health. They were also informed of the potential side effects of scopolamine and reminded throughout the study that they could withdraw whenever they felt like.

Procedure

all the participants underwent the three conditions: a placebo group who were injected with saline solution or the other groups which were 0.5 mg and 0.8 mg of scopolamine. There was a 48-hour pause between each condition and the conditions were counterbalanced. The participants also took three tests in each conditions. The tests were:

1) the free recall tests where the participants were read 14 words, 7 words were high imagery and 7 words of low imagery and the participants were asked to recall the words immediately. The list was then reread to them in a different order 5 times for a potential score of 70 points. The participants were asked to recall the words after a 40 min delay.

The second test was the new map test where participants were asked to memorize the cities of a fictitious state. After 60 seconds they were given a blank map with a list of cities. They were asked to place the cities on the map. This was repeated 4 times.

The third test was the remote memory battery where the participants were shown 150 famous faces and events and were asked to recognize them. This task was different since it involved the retrieval of Long term memory rather than the conversion of short term memory to long term memory.

3) The results showed that scopolamine played a role in inhibiting the formation of new memories but did not have a significant effect on the retrieval of long term memory. This showed that acetylcholine played a role in the encoding of both semantic and spatial memory.

Explain the formation of neural networks using one study.

Maguire

The process by which neural networks are formed is called neuroplasticity. When a neuron is stimulated, an action potential (an electrical charge) travels down the axon. Neural networks are created when a neuron or set of neurons are repeatedly stimulated. This repeated firing of the neurons, called long term potentiation, results in gene expression which causes the neurons to sprout new dendrites - known as dendritic branching. This increases the number of synapses available for the behaviour. The branching of neurons in the brain is called grey matter. Dendritic branching as a result of stimulation in the environment is seen in a study by Maguire.

Maguire carried out a study to see if neuroplasticity would be seen in the brain of London taxi drivers due to the amount of time that they had been driving the streets of London. The hypothesis was that since they were required to pass a test called "the knowledge" which required them to memorize the location of key places and routes in the city and they spent a lot of time driving around the streets of London, repeated use of the brain for spatial memory would result in neuroplasticity and a denser hippocampus.

MacGuire used 16 healthy right-handed males who were licensed taxi drivers. She compared the taxi drivers to 50 healthy right-handed males who were not taxi drivers. An MRI was used to detect changes in the structure of the brain as a result of their experience. The results showed that the taxi drivers had larger posterior hippocampi compared to the controls and that the controls had larger anterior hippocampi compared to the taxi drivers. Also, there was a positive correlation between the number of years the participants had been taxi drivers and the size of the posterior hippocampus, but a negative correlation with the size of the anterior hippocampus.

Maguire argued that this demonstrates the plasticity of the hippocampus in response to environmental demands. She argued that the posterior hippocampus stores a spatial representation of the environment and that in the London taxi drivers the volume of the posterior hippocampus expanded because of their high reliance on navigation skills and spatial memories. By repeatedly firing the neurons required to remember the spatial layout of the city of London, the number of synapses was increased, creating a greater neural network

Explain the role of one antagonist, making use of one study.

an antagonist is a drug or chemical that binds to a receptor on a neuron and inhibits the agonist from attaching to the receptor and causing a response. A receptor is a site on the neuron that receives and reads chemical signals. One antagonist is scopolamine that inhibits the acetylcholine from attaching to the receptor and allowing the formation of new memories as well as the conversion of short term memories to long term memories.

2) Study- Troster and Beatty

Aim - To investigate the role of acetylcholine in the formation and retrieval of memory.

Participants- 13 men between the ages of 31 to 59 with the mean age being 39.2. They were tested for both physical and mental health. They were also informed of the potential side effects of scopolamine and reminded throughout the study that they could withdraw whenever they felt like.

Procedure

all the participants underwent the three conditions: a placebo group who were injected with saline solution or the other groups which were 0.5 mg and 0.8 mg of scopolamine. There was a 48-hour pause between each condition and the conditions were counterbalanced. The participants also took three tests in each condition. The tests were:

1) the free recall tests where the participants were read 14 words, 7 words were high imagery and 7 words of low imagery and the participants were asked to recall the words immediately. The list was then reread to them in a different order 5 times for a potential score of 70 points. The participants were asked to recall the words after a 40 min delay.

The second test was the new map test where participants were asked to memorize the cities of a fictitious state. After 60 seconds they were given a blank map with a list of cities. They were asked to place the cities on the map. This was repeated 4 times.

The third test was the remote memory battery where the participants were shown 150 famous faces and events and were asked to recognize them. This task was different since it involved the retrieval of Long term memory rather than the conversion of short term memory to long term memory.

3) The results showed that scopolamine played a role in inhibiting the formation of new memories but did not have a significant effect on the retrieval of long term memory. This showed that acetylcholine played a role in the encoding of both semantic and spatial memory.

Explain the role of one agonist, making use of one study

An agonist is a drug or chemical that binds to the receptors in a neuron and causes a response. Receptors are sites on the neuron that receive and read chemical signals. The signals then transport information through the brain in the form of electrical signals which are called action potential. The consistent firing if these signals are known as long term potentiation which activates a gene that causes a sprout in dendritic connections increasing the neural density of the brain a process known as dendritic arborization.

Acetylcholine, a neurotransmitter, binds to a neuron receptor causing the encoding of new memory. 2) Study- Troster and Beatty

Aim - To investigate the role of acetylcholine in the formation and retrieval of memory.

Participants- 13 men between the ages of 31 to 59 with the mean age being 39.2. They were tested for both physical and mental health. They were also informed of the potential side effects of scopolamine and reminded throughout the study that they could withdraw whenever they felt like.

Procedure

all the participants underwent the three conditions: a placebo group who were injected with saline solution or the other groups which were 0.5 mg and 0.8 mg of scopolamine. There was a 48-hour pause between each condition and the conditions were counterbalanced. The participants also took three tests in each condition. The tests were:

1) the free recall tests where the participants were read 14 words, 7 words were high imagery and 7 words of low imagery and the participants were asked to recall the words immediately. The list was then reread to them in a different order 5 times for a potential score of 70 points. The participants were asked to recall the words after a 40 min delay.

The second test was the new map test where participants were asked to memorize the cities of a fictitious state. After 60 seconds they were given a blank map with a list of cities. They were asked to place the cities on the map. This was repeated 4 times.

The third test was the remote memory battery where the participants were shown 150 famous faces and events and were asked to recognize them. This task was different since it involved the retrieval of Long term memory rather than the conversion of short term memory to long term memory.

3) The results showed that scopolamine played a role in inhibiting the formation of new memories but did not have a significant effect on the retrieval of long term memory. This showed that acetylcholine played a role in the encoding of both semantic and spatial memory.

Describe one technique used to study the brain in relation to behaviour.

Use of fMRI (Sharot et al )

1. The aim of this study was ro determine the potential of biological factors on flashbulb memories

Participants-

24 Participants who were in New York when the events on 9/11 took place.

Procedure

They were placed in an fMRI and while in the scanner, they were presented with word cues on a screen. In addition, the word summer and September were projected along each word in order to have the participants link the word to either summer holidays or the events of 9/11. Their brain activities were then observed and their memories from the summer served as a baseline of brain activity for evaluating the nature of 9/11 memories.

2) After the scans, Sharot and her team found that the activation of the amygdala for the participants who were downtown was higher when they recalled memories of the terrorist attack than when they recalled events from the preceding summer, whereas those participants who were further away from the event had equal levels of response in the amygdala when recalling both events. The strength of amygdala activation at retrieval was shown to correlate with flashbulb memories. The use of fMRI in this study was crucial because fMRIs not only show the structure of the brain, but also the function. The researches were therefore able to see when and how the amygdala was stimulated as the participants recalled emotional memories of their summers which aided in their conclusion.

Explain the use of one research method in one study using the biological approach to understanding human behavior.

There are two main methods of research used in psychology: quantitative research and qualitative research. Quantitative research ranges from laboratory experiments that are highly controlled and artificial to field experiments that are carried out in the real world which manipulating the independent variable. There also quasi-experiments that do not show causality and also correlational studies which only indicate either a negative or positive correlation. Quantitative methods of research vary from naturalistic observations to case studies, surveys, and interviews.

2) Study- Troster and Beatty

Aim - To investigate the role of acetylcholine in the formation and retrieval of memory.

Participants- 13 men between the ages of 31 to 59 with the mean age being 39.2. They were tested for both physical and mental health. They were also informed of the potential side effects of scopolamine and reminded throughout the study that they could withdraw whenever they felt like.

Procedure

all the participants underwent the three conditions: a placebo group who were injected with saline solution or the other groups which were 0.5 mg and 0.8 mg of scopolamine. There was a 48-hour pause between each condition and the conditions were counterbalanced. The participants also took three tests in each condition. The tests were:

1) the free recall tests where the participants were read 14 words, 7 words were high imagery and 7 words of low imagery and the participants were asked to recall the words immediately. The list was then reread to them in a different order 5 times for a potential score of 70 points. The participants were asked to recall the words after a 40 min delay.

The second test was the new map test where participants were asked to memorize the cities of a fictitious state. After 60 seconds they were given a blank map with a list of cities. They were asked to place the cities on the map. This was repeated 4 times.

The third test was the remote memory battery where the participants were shown 150 famous faces and events and were asked to recognize them. This task was different since it involved the retrieval of Long term memory rather than the conversion of short term memory to long term memory.

3) The results showed that scopolamine played a role in inhibiting the formation of new memories but did not have a significant effect on the retrieval of long term memory. This showed that acetylcholine played a role in the encoding of both semantic and spatial memory.

Explain the use of one research method in one study of the brain and behaviour.

There are two main methods of research used in psychology: quantitative research and qualitative research. Quantitative research ranges from laboratory experiments that are highly controlled and artificial to field experiments that are carried out in the real world which manipulating the independent variable. There also quasi-experiments that do not show causality and also correlational studies which only indicate either a negative or positive correlation. Quantitative methods of research vary from naturalistic observations to case studies, surveys, and interviews.

Sharot et al conducted a quasi-experiment to determine how potential biological factors affect flashbulb memories. 24 Participants who were in New York when the events of 9/11 took place.

Procedure

They were placed in an fMRI and while in the scanner, they were presented with word cues on a screen. In addition, the word summer and September were projected along with each word in order to have the participants link the word to either summer holidays or the events of 9/11. Their brain activities were then observed and their memories from the summer served as a baseline of brain activity for evaluating the nature of 9/11 memories.

2) After the scans, Sharot and her team found that the activation of the amygdala for the participants who were downtown was higher when they recalled memories of the terrorist attack than when they recalled events from the preceding summer, whereas those participants who were further away from the event had equal levels of response in the amygdala when recalling both events. The strength of amygdala activation at retrieval was shown to correlate with flashbulb memories. The use of fMRI in this study was crucial because fMRIs not only show the structure of the brain, but also the functionality. The researches were, therefore, able to see when and how the amygdala was stimulated as the participants recalled emotional memories of their summers which aided in their conclusion.

Explain one ethical consideration relevant to one study using a biological approach

to understanding human behaviour.

Ethical considerations are a set of rules that guide the science community on how to carry out an experiment or study mostly in order to minimize harm. One important ethical consideration is that participants should have a right to withdraw from a study at any point during the study.

One study that follows this ethical consideration is the Troster and Beatty study that aimed to investigate how acetylcholine influenced the formation and retrieval of memories. The researchers were going to use an antagonist, scopolamine, to block the acetylcholine receptor site in order to see that effect when the participants carry out different tasks that included 1) the free recall tests where the participants were read 14 words, 7 words were high imagery and 7 words of low imagery and the participants were asked to recall the words immediately. The list was then reread to them in a different order 5 times for a potential score of 70 points. The participants were asked to recall the words after a 40 min delay.

The second test was the new map test where participants were asked to memorize the cities of a fictitious state. After 60 seconds they were given a blank map with a list of cities. They were asked to place the cities on the map. This was repeated 4 times.

The third test was the remote memory battery where the participants were shown 150 famous faces and events and were asked to recognize them. This task was different since it involved the retrieval of Long term memory rather than the conversion of short term memory to long term memory.

The participants were informed of the side effects of scopolamine which included dry mouth, forgetfulness, sedation, and hallucinations. However, the participants were not forced to take part in the study but were constantly reminded that they could stop taking part in the study whenever they felt like it.

Explain one ethical consideration relevant to one study of the brain and behaviour.

Ethical considerations are a set of rules that guide the science community on how to carry out an experiment or study mostly in order to minimize harm. One important ethical consideration is that participants should have a right to withdraw from a study at any point during the study.

One study that followed ethical considerations was HM: Milner, which aimed to investigate the effect surgery had on the patient HM. The research, Milner, used method triangulation from IQ tests to interviews in order to examine the effect of the surgery. HM who had sustained head injuries at the age of 7 had anterograde amnesia and he could not acquire new episodic or semantic memory. However, HM still had a working memory, procedural memory, and even spatial memory as he could draw a cognitive map of his house. When an MRI scan of HM's brain was taken, it was evident that most of the damage had occurred on the hippocampus and this explains why HM could hardly form new memories as the hippocampus is involved in the transfer of short term memory to long term memory.

Milner, in all the investigations she did on HM, met high ethical consideration of consent as she asked for HMs permission before sharing any of his medical documents and also kept confidential information only to herself and HMs family.

Explain the role of one hormone in human behaviour, making use of one study.

McGaugh and Cahill

1. Hormones are chemical messengers released from endocrine glands that travel through the blood system to influence or regulate behaviors such as aggression, mating e.t.c Some hormones also have an influence on the nervous system affecting the receiving and processing of stimuli. Most hormones are produced in the pituitary glands located between the hypothalamus and the pineal gland in the brain. Hormones, unlike neurotransmitters, take a longer time to respond to stimuli but their response has a prolonged effect.

2. The aim of the study was to investigate the role of emotion in the creation of memories.

Participants were divided into two groups. Each group saw 12 slides which were accompanied by a very different story. In the first condition, the participants heard a rather boring story about a woman and her son who paid a visit to the son's father in a hospital where they witnessed the staff in a disaster preparation drill of a simulated accident victim.

In the second condition, the participant heard a story where the boy was involved in a car accident where his feet were severed. He was quickly taken to the hospital where the surgeons reattach the injured limbs. Then he stayed in the hospital for some weeks and then went home with his mother. Two weeks after participating in the experiment, the participants were asked to come back and their memory for specific details of the story were tested. The test was a recognition task that consisted of a series of questions about the slides with three options for them to choose from.

3. The researchers then did a follow-up study. In the follow-up study the above procedure was repeated, but this time the participants in the "traumatic story" condition were injected with a beta-blocker called propranolol which was used to prevent activation of the amygdala.

In the original version of the experiment, the researchers found that the participants who had heard the more emotionally arousing story demonstrated better recall of specific details of the story. They could also recall more details from the slides. In the follow-up study, they found that those that had received the beta-blocker did no better than the group that had heard the "mundane" story. Those that had heard the tragic story, produced the stress hormone, adrenaline, that is produced by the adrenal glands. When adrenaline reaches the brain it activates the amygdala to send a message that something important or dangerous has happened. The amygdala is believed to play a significant role in the creation of memories linked to emotional arousal, hence the group that saw the tragic story was able to recall the accounts better.

Describe one study of the role of pheromones in human behaviour.

Wedekind

1)Wedekind studied the Major Histocompatibility Complex (MHC), a group of genes that play an important role in the immune system.

AIM

The aim of the study was to determine whether one's MHC would affect mate choice.

Participants

49 female and 44 male students from the University of Bern, Switzerland.

Procedure

Each participant was "typed" for their MHC, and a wide variance of MHC was included in the sample. It was also noted if the women were taking oral contraceptives.

The men were asked to wear a T-shirt for two nights and to keep the T-shirt in an open plastic bag during the day. They were given perfume-free detergent to wash clothes and bed clothes and perfume-free soap for showering. They were asked not to use any deodorants or perfumes, to refrain from smoking tobacco or drinking alcohol, to avoid all spicy foods and to not engage in any sexual activity.

Two days later, the women were asked to rank the smell of 7 t-shirts, each in a cardboard box with a "smelling hole." The women were tested whenever possible in the second week after the beginning of menstruation, as women appear to be most odour-sensitive at this time.

The women were also asked to prepare themselves for the experiment by using a nose spray for the 14 days before the experiment to support regeneration of the nasal mucous membrane if necessary - as well as a preventive measure against colds or flu. Each woman was also given a copy of Süskind's novel Perfume to sensitize their smell perception.

Three of the seven boxes contained T-shirts from men with MHC similar to the woman's own; three contained T-shirts from MHC dissimilar men; and one contained an unworn T-shirt as a control. Alone in a room, every woman scored the odours of the T-shirts for intensity (range 0-10) and for pleasantness and sexiness (range 0 -10, 5 = neutral).

2) Findings

Women scored male body odours as more pleasant when they differed from their own MHC than when they were more similar. This difference in odour assessment was reversed when the women rating the odours were taking oral contraceptives. This suggests that the MHC may influence human mate choice, which is one of the effects researchers think pheromones have in human behavior.

Explain the use of one research method in one study of hormones or pheromones and behaviour.

Hormones are chemicals secreted by the endocrine system and affect our behavior. Unlike neurotransmitters, hormones are released directly into the bloodstream and have an extended effect. Hormones can only produce reactions in certain cells - known as target cells - that have an appropriate receptor site for the hormone. When the hormone binds to the target cell, it either increases or decreases its function.

2) Study McGaugh and Cahill

Aim- The aim of McGaugh and Cahill's study was to study the role of emotion on the creation of memories.

Participants-

Participants were divided into two groups. Each group saw 12 slides which were accompanied by a very different story. In the first condition, the participants heard a rather boring story about a woman and her son who paid a visit to the son's father in a hospital where they witnessed the staff in a disaster preparation drill of a simulated accident victim.

In the second condition, the participant heard a story where the boy was involved in a car accident where his feet were severed. He was quickly taken to the hospital where the surgeons reattach the injured limbs. Then he stayed in the hospital for some weeks and then went home with his mother. Two weeks after participating in the experiment, the participants were asked to come back and their memory for specific details of the story were tested. The test was a recognition task that consisted of a series of questions about the slides with three options for them to choose from.

The researchers then did a follow-up study. In the follow-up study the above procedure was repeated, but this time the participants in the "traumatic story" condition were injected with a beta-blocker called propranolol.

3) In the original version of the experiment, the researchers found that the participants who had heard the more emotionally arousing story demonstrated better recall of specific details of the story. They could also recall more details from the slides. In the follow-up study, they found that those that had received the beta-blocker did no better than the group that had heard the "mundane" story. This is because the beta-blocker blocked the adrenaline's receptor site. These, therefore, conclude that adrenaline plays a significant role in assisting the amygdala create memories linked to emotional arousal.

Explain one ethical consideration relevant to one study of hormones or pheromones and behaviour.

Ethical considerations are a set of rules that guide the science community on how to carry out an experiment or study mostly in order to minimize harm. One important ethical consideration is that participants should have a right to withdraw from a study at any point during the study.

McGaugh and Cahill study that aimed at Aim- The aim of McGaugh and Cahill's study was to study the role of emotion on the creation of memories.

Participants-

Participants were divided into two groups. Each group saw 12 slides which were accompanied by a very different story. In the first condition, the participants heard a rather boring story about a woman and her son who paid a visit to the son's father in a hospital where they witnessed the staff in a disaster preparation drill of a simulated accident victim.

In the second condition, the participant heard a story where the boy was involved in a car accident where his feet were severed. He was quickly taken to the hospital where the surgeons reattach the injured limbs. Then he stayed in the hospital for some weeks and then went home with his mother. Two weeks after participating in the experiment, the participants were asked to come back and their memory for specific details of the story were tested. The test was a recognition task that consisted of a series of questions about the slides with three options for them to choose from.

The researchers then did a follow-up study. In the follow-up study the above procedure was repeated, but this time the participants in the "traumatic story" condition were injected with a beta-blocker called propranolol.

3) In the original version of the experiment, the researchers found that the participants who had heard the more emotionally arousing story demonstrated better recall of specific details of the story. They could also recall more details from the slides. In the follow-up study, they found that those that had received the beta-blocker did no better than the group that had heard the "mundane" story. This study does not discuss whether the participants were protected from undue stress and harm. We are not told whether any of the participants suffering from psychological trauma by watching the traumatic slid or whether the propranolol causes any side effects that the participants were made aware of.

Describe one study of the role of genes in human behaviour.

1) Aim - the role that genetics play in major depressive disorder

Participants- The sample was made up of 15,493 complete twin pairs listed in the national Swedish Twin Registry. The twins were born between 1886 and 1958. Only twins whose zygosity could be verified were used in the study.

Procedure

The researchers used a team of trained interviewers to carry out telephone interviews. Interviews were carried out between March 1998 and January 2003. The interviewers assessed lifetime major depression by using modified DSM-IV criteria. 8056 twins met the criteria for a diagnosis of major depression at some point in their life - and 322 twins voluntarily discussed a history of antidepressant treatment.

In addition to this information, the interviewers also asked questions about the twins "shared environment" - that is, when they were living in the same household - and their "individual-specific environment" - that is, adult personal life events that may make members of the twin pair more susceptible to depression.

2) The results indicate that the heritability of major depression was significantly higher in women than men. In addition, the correlations were significantly higher in monozygotic than in dizygotic twins. The estimated heritability of major depression was 0.38, in line with previous research. They also found no correlation between the number of years that the twins had lived together and lifetime major depression.

There were also no significant differences seen in the roles of genetic and environmental factors in major depression in the three cohorts spanning birth years 1900-1958. Even when they split the entire cohort into pre and post World War II, there was no significant difference.

This study suggests both that the heritability of major depression is higher in women than in men and that some genetic risk factors for major depression are sex-specific. In addition, the study confirms the level of heritability of major depression found in other studies, strengthening the reliability of European twin studies.

Explain the use of one research method in one study of genetics and behaviour.

Kendel et al

1. Genetic research in humans is to a large extent based on correlational studies. This means that a researcher establishes that there is a relationship between variables, but the researcher does not manipulate an independent variable as in an experiment. Therefore, no cause and effect can be determined. One of the ways to study the possible correlation of genetic inheritance and behaviour is through twin research. Researchers study twins because they share common genetic material. Since the completion of the Human Genome Project, we have seen a change in how genetic research is carried out.

Aim - the role that genetics play in major depressive disorder

Participants- The sample was made up of 15,493 complete twin pairs listed in the national Swedish Twin Registry. The twins were born between 1886 and 1958. Only twins whose zygosity could be verified were used in the study.

Procedure

The researchers used a team of trained interviewers to carry out telephone interviews. Interviews were carried out between March 1998 and January 2003. The interviewers assessed lifetime major depression by using modified DSM-IV criteria. 8056 twins met the criteria for a diagnosis of major depression at some point in their life - and 322 twins voluntarily discussed a history of antidepressant treatment.

In addition to this information, the interviewers also asked questions about the twins "shared environment" - that is, when they were living in the same household - and their "individual-specific environment" - that is, adult personal life events that may make members of the twin pair more susceptible to depression.

The results indicate that the heritability of major depression was significantly higher in women than men. In addition, the correlations were significantly higher in monozygotic than in dizygotic twins. The estimated heritability of major depression was 0.38, in line with previous research. They also found no correlation between the number of years that the twins had lived together and lifetime major depression.

3) The use of a correlational methodology to conduct this study indicates that this is not a true experiment since no cause and effect relationship can be determined. The interviewers did not manipulate any independent variable by officially diagnosing the twins and they accepted the diagnoses made by clinicians when it was reported by the interviewee; as we know, clinical diagnoses are not highly reliable and making such a diagnosis by telephone may be considered of questionable validity. Therefore, although correlation was the best method of research to conduct this study as the researchers had a large population with limited data, the method was not effective enough to illustrate causation but rather strengthen data from previous researches.

Explain one ethical consideration relevant to one study of genetics and behaviour.

Ethical considerations are a set of rules that guide the science community on how to carry out an experiment or study mostly in order to minimize harm. One important ethical consideration is that participants should have a right to withdraw from a study at any point during the study.

Aim - the role that genetics play in major depressive disorder

Participants- The sample was made up of 15,493 complete twin pairs listed in the national Swedish Twin Registry. The twins were born between 1886 and 1958. Only twins whose zygosity could be verified were used in the study.

Procedure

The researchers used a team of trained interviewers to carry out telephone interviews. Interviews were carried out between March 1998 and January 2003. The interviewers assessed lifetime major depression by using modified DSM-IV criteria. 8056 twins met the criteria for a diagnosis of major depression at some point in their life - and 322 twins voluntarily discussed a history of antidepressant treatment.

In addition to this information, the interviewers also asked questions about the twins "shared environment" - that is, when they were living in the same household - and their "individual-specific environment" - that is, adult personal life events that may make members of the twin pair more susceptible to depression.

The results indicate that the heritability of major depression was significantly higher in women than men. In addition, the correlations were significantly higher in monozygotic than in dizygotic twins. The estimated heritability of major depression was 0.38, in line with previous research. They also found no correlation between the number of years that the twins had lived together and lifetime major depression.

Explain one evolutionary explanation of one behaviour.

Evolutionary psychology uses evolutionary theory to explain similarities in psychological characteristics. According to evolutionary psychologists, patterns of behavior have evolved through natural selection, in the same way that physical characteristics have evolved. Because of natural selection, Adaptive Behaviors, or behaviors that increase reproductive success, are kept and passed on from one generation to the next.

Ronay and von Hippel (2010) carried out a study to determine if men would take greater risks in the presence of an attractive female, than in the presence of a male. In addition, they wanted to see if testosterone played a role in this behaviour.

They hypothesized that they would take greater risks as a result of intrasexual selection - that is, he who makes the greatest impression, gets the girl.

The sample was made up of 96 young adult Australian male skateboarders with a mean age of 21.58. Participants were recruited at skateboard parks. 43 were assigned to the male-researcher condition and 53 were assigned to the female-researcher condition. Tests were conducted between 2 and 6 pm.

Skateboarders were asked to do one "easy trick" and one difficult trick which they could successfully complete approximately 50% of the time. They were asked to do each trick 10 times.

After a break, they were asked to make 10 more attempts of each trick but this time in front of the same male researcher or an attractive 18-year-old female researcher who was blind to the hypothesis. The attractiveness of the researcher was established by having 20 male raters view photos of potential female experimenters. The skateboarders' attempts were coded for one of three outcomes: success, crash landing or aborted attempt. High levels of aborted attempts would be seen as an indicator of low-risk taking.

Saliva samples were also collected at the conclusion of the experiment to measure for testosterone. Heart rate was measured by having participants wear a Nordic sports watch. Measurements were taken immediately prior to the test and then measured throughout the task.

As expected, participants took greater risks on the difficult tricks in the presence of the female researcher - that is, they aborted the trick fewer times. In addition, testosterone levels were higher in the men that skateboarded in front of the female researcher than in front of the male researcher. There was no significant difference in the measure of heart rate between the two groups.

The study showed that young men take great physical risks when in the presence of an attractive woman and that testosterone may account for this behaviour.

According to evolutionary theory, this makes sense. The increased risk-taking is a sign to potential mates that the male is healthy, strong and dominant - that is, would be able to intimidate any potential rival.

Explain the use of twin studies using one study.

Researchers study twins because they share common genetic material and it is important to see how people with similar genetic material will have different behaviors if exposed to different environments. The vice versa is also true as people twins brough up in different environments might end up having similar or comparable behaviors. However, genetic research in humans is to a large extent based on correlational studies. This means that a researcher establishes that there is a relationship between variables, but the researcher does not manipulate an independent variable as in an experiment. Therefore, no cause and effect can be determined.

Aim - the role that genetics play in major depressive disorder

Participants- The sample was made up of 15,493 complete twin pairs listed in the national Swedish Twin Registry. The twins were born between 1886 and 1958. Only twins whose zygosity could be verified were used in the study.

Procedure

The researchers used a team of trained interviewers to carry out telephone interviews. Interviews were carried out between March 1998 and January 2003. The interviewers assessed lifetime major depression by using modified DSM-IV criteria. 8056 twins met the criteria for a diagnosis of major depression at some point in their life - and 322 twins voluntarily discussed a history of antidepressant treatment.

In addition to this information, the interviewers also asked questions about the twins "shared environment" - that is, when they were living in the same household - and their "individual-specific environment" - that is, adult personal life events that may make members of the twin pair more susceptible to depression.

The results indicate that the heritability of major depression was significantly higher in women than men. In addition, the correlations were significantly higher in monozygotic than in dizygotic twins. The estimated heritability of major depression was 0.38, in line with previous research. They also found no correlation between the number of years that the twins had lived together and lifetime major depression.

3) The use of a correlational methodology to conduct this study indicates that this is not a true experiment since no cause and effect relationship can be determined. The interviewers did not manipulate any independent variable by officially diagnosing the twins and they accepted the diagnoses made by clinicians when it was reported by the interviewee; as we know, clinical diagnoses are not highly reliable and making such a diagnosis by telephone may be considered of questionable validity. Therefore, although the correlation was the best method of research to conduct this study as the researchers had a large population with limited data, the method was not effective enough to illustrate causation but rather strengthen data from previous researches.

Explain the use of family studies (kinship studies) using one study.

Weissman et al

1) In family studies, researchers look at the incidence of behavior over generations and this is usually limited to 3 generations.

2) Weissman et al (2005) carried out a longitudinal family study with a sample of 161 grandchildren and their parents and grandparents to study the potential genetic nature of Major Depressive Disorder.

The study took place over a twenty-year period, looking at families at high and low risk for depression. The original sample of depressed patients (now, the grandparents) was selected from an outpatient clinic with a specialization in the treatment of mood disorders. The non-depressed participants were selected from the same local community. The original sample of parents and children were interviewed four times during this period. The children are now adults and have children of their own - allowing for the study of the third generation.

Data was collected from clinicians, blind to the past diagnosis of depression or to data collected in previous interviews. Children were evaluated by two experienced clinicians - with one being a child psychiatrist and the other a psychologist. The inter-rater reliability of their diagnoses was 0.82 for MDD, 0.65 for anxiety disorders and 0.94 for alcohol dependency.

3) The researchers found high rates of psychiatric disorders in the grandchildren with two generations of major depression. By 12-years-old, 59.2% of the grandchildren were already showing signs of a psychiatric disorder - most commonly anxiety disorders. Children had an increased risk of any disorder if depression was observed in both the grandparents and the parents, compared to children where their parents were not depressed. In addition, the severity of a parent's depression was correlated with an increased rate of a mood disorder in the children.

On the other hand, if a parent was depressed but there was no history of depression in the grandparents, there was no significant effect of parental depression on the grandchildren.