PYCHOLOGY - BRAIN AND NEUROPSYCHOLOGY

A study on how prisoners responded to traumatic situations used a systematic sample of 50 prisoners from a prison population of 500. They had their heart rate measured whilst being shown a film of someone being murdered. They were also interviewed afterwards about how stressful they found the film.

1. Explain how the researcher would have recruited a systematic sample for this study. [2 marks]

He could have obtained a list of all 500 prisoners and then selected every 10th person from the list.

A study on how prisoners responded to traumatic situations used a systematic sample of 50 prisoners from a prison population of 500. They had their heart rate measured whilst being shown a film of someone being murdered. They were also interviewed afterwards about how stressful they found the film.

Explain the difference between qualitative and quantitative methods in psychology. Refer to the above study in your answer. [3 marks]

They differ in terms of the type of data they use. Quantitative methods use data that can be counted such as the prisoner’s heart rate. Qualitative methods, on the other hand, use non-numerical data that can be expressed in words such as the participants’ responses to how stressful they found the film.

What is meant by the term ‘somatic nervous system’? [1 mark]

The somatic nervous system transmits information from sense organs to the central nervous system (CNS). It also receives information from the CNS that directs muscles to act.

Explain the function of the peripheral nervous system. [3 marks]

The peripheral nervous system (PNS) sends information to the central nervous system (CNS) from the outside world and transmits messages from the CNS to muscles and glands. The PNS is sub-divided into the autonomic nervous system (ANS) and the somatic nervous system (SNS).

Draw a diagram showing how the nervous system is structured. Include the following in your diagram: central nervous system, peripheral nervous system, somatic nervous system, autonomic nervous system. [4 marks]

Holly sees herself as a bit of a practical joker and decides to surprise her friend Tom by jumping out from behind the door when he walks into the room. Tom’s reaction makes Holly feel bad as his face goes red and he starts breathing more heavily.

Use your knowledge of the autonomic nervous system and the fight or flight response to explain Tom’s reaction to Holly’s surprise. [4 marks]

Tom’s reaction to Holly’s surprise relates to the sympathetic branch of the autonomic nervous system being triggered. This causes his adrenal glands to release adrenaline, which makes his heart beat faster, his face goes red and his breathing to become heavier.

This produces a fight or flight response to make an animal ready to stand and fight or to flee away from danger. The surprise has been interpreted as a threat and so causes these increases in physiological arousal which prepare him to fight or run away.

Identify three bodily changes that occur during the fight or flight response. [3 marks]

Pupils dilate, increased heart rate, increased breathing.

Explain what happens in the fight or flight response. [5 marks]

The fight or flight response is the immediate physiological response of an animal when confronted with a threatening or stressful situation. The actions of the sympathetic division of the autonomic nervous system cause the body to become physiologically aroused because of the effects of the hormone adrenaline. This prepares the body to be able to fight the threat or run away by increasing heart rate and breathing, which causes the person to sweat more. All of these changes happen almost immediately after a threat is perceived. When the threat has passed, the parasympathetic division returns the body to a resting state. This reduces the activities of the body that were increased during fight or flight response. The person may feel hungry or thirsty having used up so much energy and because digestion is then stimulated.

Explain the function of the autonomic nervous system. [2 marks]

The autonomic nervous system transmits information to and from internal bodily organs. It is ‘autonomic’ as the system operates involuntarily (i.e. it is automatic). It has two main divisions: the sympathetic and parasympathetic nervous systems.

A study investigated how physiological arousal affects judgements of attractiveness. One group of participants were asked to run on the spot (high arousal condition) as they rated 10 photos for attractiveness (on a scale of 1 to 5). A second group were asked to rate attractiveness while swaying gently (low arousal condition).

Explain why the second group had to sway gently while completing the task. [3 marks]

If they didn’t do something while doing the rating task this might have acted as an extraneous variable because both groups have to be doing something – one is high arousal and one is low arousal.

A study investigated how physiological arousal affects judgements of attractiveness. One group of participants were asked to run on the spot (high arousal condition) as they rated 10 photos for attractiveness (on a scale of 1 to 5). A second group were asked to rate attractiveness while swaying gently (low arousal condition).

Explain how the researcher could have standardised the procedures. [3 marks]

He could have ensured that:

• All of the participants were tested by the same investigator.

• The same rating scale was used when assessing the attractiveness of each participant.

A study investigated how physiological arousal affects judgements of attractiveness. One group of participants were asked to run on the spot (high arousal condition) as they rated 10 photos for attractiveness (on a scale of 1 to 5). A second group were asked to rate attractiveness while swaying gently (low arousal condition).

Explain one weakness of measuring attractiveness using a questionnaire. [2 marks]

It may lack validity as it is reducing human behaviour (e.g. attractiveness) down to a score

Explain the role of the autonomic nervous system in the James–Lange theory of emotion. [3 marks]

The James–Lange theory says it’s the physical changes that occur first. The sympathetic division of the ANS is activated and this, in turn, leads to the release of adrenaline, creating physiological arousal experienced as an increase in bodily activity such as a rise in our heart rate and blood pressure (the fight or flight response).

The labelling of the emotion comes afterwards. The brain interprets the physiological activity and decides whether the arousal is, for example, fear or love.

Explain one criticism of the James–Lange theory of emotion. [4 marks]

One weakness of the theory is that it has been challenged by the Cannon–Bard theory which argues that we experience emotions at the same time as physiological arousal (they are simultaneous) and not one after the other. For example, we feel embarrassed (emotion) at the same time as we blush (physical reaction). Walter Cannon also argued that some physiological changes (for example, during exercise) do not necessarily lead to an emotion as the James–Lange theory would predict. Therefore, the Cannon–Bard theory draws attention to emotional situations that the James–Lange theory would struggle to explain.

Outline and evaluate the James–Lange theory of emotion. [9 marks]

The theory states physiological arousal comes first and emotion after. An event causes physiological arousal in the following way: The hypothalamus activates the sympathetic division of the autonomic nervous system (ANS). Adrenaline is then released which creates physiological arousal. This is experienced as an increase in bodily activity such as a rise in our heart rate and blood pressure (the fight or flight response). The brain interprets the physiological activity which causes emotions. If there are no physiological changes then emotions are not experienced. For example, if you stand in front of your class and your heart rate doesn’t increase, then you do not feel scared because there are no physiological changes.

One strength of the theory is there are real-life examples of emotions following physiological arousal. Emotional states seem to follow physiological arousal in cases such as phobias or panic disorders. This suggests that the emotion and avoidance occur as a result of the physiological reaction, as predicted by the theory.

A weakness is that it is challenged by the Cannon–Bard theory. We experience some emotions (e.g. embarrassment) at the same time as physiological arousal and not one after the other. Therefore, this theory can explain emotional situations that the James–Lange theory cannot.

Another weakness is that the theory is challenged by the two-factor theory. We need arousal plus social cues to correctly label the emotion we are feeling (Schachter and Singer). This means the James–Lange theory does not explain how a person ‘decides’ the emotion they are experiencing.

Use your knowledge of synaptic transmission to explain how SSRI drugs work. Refer to the release and reuptake of neurotransmitters in your answer. [4 marks]

• An electrical impulse travelling along a neuron causes serotonin molecules to be released from the vesicles in the presynaptic neuron.

• The molecules cross the synaptic cleft and attach to the receptors on the postsynaptic neuron.

• SSRIs prevent any remaining serotonin being absorbed back into the presynaptic neuron, plus more serotonin may be released.

• This leads to more serotonin being available at the synaptic cleft, so more will attach to postsynaptic receptors and the postsynaptic neuron is more likely to fire and pass on messages that will increase mood.

Explain the function of a motor and a relay neuron. [2 marks]

Motor neurons carry messages from the central nervous system to effectors in our body, such as muscles and glands. They have short dendrites and long axons.

Relay neurons connect sensory neurons to motor neurons as the neurons do not connect directly. Relay neurons also connect to other relay neurons. They have short dendrites and short axons.

Outline how excitation and inhibition work together. [3 marks]

Excitation is where some neurotransmitters generally increase the positive charge of the next neuron, making it more likely to fire. Inhibition is where some neurotransmitters generally increase the negative charge of the next neuron, making it less likely to fire.

The summation of the two processes results in an overall negative or positive charge at the postsynaptic neuron and determines whether a message is sent or not.

Describe the process involved in synaptic transmission. Refer to the release and reuptake of neurotransmitters in your answer. [4 marks]

Neurons communicate using neurotransmitters which are released from the presynaptic to the postsynaptic neuron across the synaptic cleft. Neurotransmitters are stored in vesicles at terminal buttons of the presynaptic neuron. An electrical signal releases neurotransmitters into the synaptic cleft.

Once the transmitter crosses the cleft, it is taken up by the next neuron at the postsynaptic receptor sites. These are located on the dendrites of the next neuron. If the summation of chemical signals is positive, the chemical message is turned back into an electrical impulse which sets off again down the neuron.

The chemical neurotransmitter left in the gap is broken down by enzymes and reabsorbed by the presynaptic neuron so it can be used again.

A researcher wanted to see the effect of environment on learning. One group (group 1) of rats were brought up in a stimulating environment that promoted neuronal growth whilst the other group (group 2) were brought up in an unstimulating environment. Both groups were then timed on how quickly they could escape from a maze.

1. Write a suitable alternative hypothesis for this study. [2 marks]

Rats brought up in a stimulating environment escape from the maze more quickly than rats brought up in an unstimulating environment (a possible directional hypothesis).

The time taken for rats brought up in a stimulating environment to escape from the maze is different from the time taken by rats brought up in an unstimulating environment (a possible non-directional hypothesis).

A researcher wanted to see the effect of environment on learning. One group (group 1) of rats were brought up in a stimulating environment that promoted neuronal growth whilst the other group (group 2) were brought up in an unstimulating environment. Both groups were then timed on how quickly they could escape from a maze.

Explain how the researcher might allocate rats to group 1 or group 2. [2 marks]

The researcher could use randomisation. This is done by numbering each rat and putting their numbers in a hat and then drawing half of the numbers out, which will be the rats who go in group 1.

What is meant by the term ‘neuronal growth’? [2 marks]

It is about the growing efficiency of neurons. During learning, groups of neurons called cell assemblies fire together. This leads to the neurons becoming more efficient. They change physically and grow so that they can manage the new learning more effectively, which is called neuronal growth.

Outline Hebb’s theory of learning. [4 marks]

Hebb suggested that synaptic connections in the brain become stronger the more they are used. This means that the brain is not fixed in structure, but that it is constantly changing and developing. Therefore the brain can adapt, change structure and form new connections as we learn. Hebb argued that learning leaves a trace in the brain, known as an ‘engram’. The trace that learning leaves in the brain can be made permanent if we continually practise and rehearse the thing we are learning. During learning, groups of neurons, known as cell assemblies, fire together. The more this happens, the stronger the synaptic connections between them become

Describe and evaluate Hebb’s theory of neuronal growth. [9 marks]

Hebb suggested that synaptic connections in the brain become stronger the more they are used. This means that the brain is not fixed in structure, but that it is constantly changing and developing. Therefore the brain can adapt, change structure and form new connections as we learn. Hebb argued that learning leaves a trace in the brain, known as an ‘engram’. The trace that learning leaves in the brain can be made permanent if we continually practise and rehearse the thing we are learning. During learning, groups of neurons, known as cell assemblies, fire together. The more this happens, the stronger the synaptic connections between them become.

A strength of Hebb’s theory is that it is scientific. Hebb explained learning in terms of brain function, which provided an objective basis for understanding behaviour. This shows that learning can be studied through brain processes.

A further strength of Hebb’s theory is it can be applied to education. He found that rats raised in stimulating settings were better able to find their way through mazes as adults. This could be applied to education by creating more stimulating environments to encourage learning.cA weakness with Hebb’s theory is that it reduces learning to a neuronal level. This means that other levels of understanding are ignored, such as Piaget’s ideas about how accommodation moves learning forwards. This is an issue as a more complete account of learning would discuss non-biological factors as well.

An accident meant that Fred’s brain was damaged. He struggles to think clearly at times and finds it difficult to make future plans. He also can no longer move his right arm.

Use your knowledge of psychology to identify which area of his brain Fred damaged and on which side of his brain this damage occurred. Explain your answers. [4 marks]

It looks like Fred has damaged his frontal lobe as this affects processes such as thinking and planning ahead. This could explain why he struggles to focus his thoughts or make future plans.

It also looks like he has damaged the left side of his brain as this controls the right side of his body, which is perhaps why he cannot move his right arm.

Identify the location and the basic function of the occipital lobe. [2 marks]

At the back of the brain is the occipital lobe which contains the visual area. Each eye sends information to the visual areas on each side of the brain (each hemisphere).

Use your knowledge of localisation of function to state what would happen if a person damaged the somatosensory area of their brain. [2 marks]

Damage to the somatosensory cortex would mean the person would be less able to feel things like pain and changes in temperature.

Explain how knowledge about localisation of function has contributed to our understanding of behaviour. [6 marks]

Localisation means that particular areas of the brain have particular functions and do particular jobs. This means that if a certain brain area becomes damaged – through illness or injury – then the function it controls may be affected or lost altogether.

This has contributed to our understanding of behaviour because we now understand that damage to the motor area in the left hemisphere affects the right side of the body. Damage to the visual area such as the left visual cortex may cause blindness in the right visual field of both eyes and damage to the auditory area may cause partial or total hearing loss.

In most people, the areas controlling language are in the left hemisphere only. This means that damage to the right side of the brain may not affect a person’s language abilities all that much whereas damage to the left side may affect language quite significantly. Damage to the left temporal lobe may produce Wernicke’s aphasia, which is difficulty understanding and producing language.

When I smell bacon, it triggers a memory of having breakfast at home as a child.

Use your knowledge of Penfield’s study of the interpretive cortex to explain this experience. [3 marks]

Penfield electrically stimulated different areas of the temporal lobe and found that this led to the vivid recall of specific memories. So the memory of bacon frying may stimulate an area of the temporal lobe and trigger this other memory

What is meant by the ‘interpretive cortex’? [2 marks]

The interpretive cortex is an area of the temporal lobe of the brain where interpretations of memories are stored, i.e. the emotional component of the memory.

Explain what Penfield’s study of the interpretive cortex can tell us about localisation of function. [3 marks]

Penfield concluded that the area of the temporal lobe he had stimulated must have a role in storing memories of previous events. He found that the interpretive cortex is the area that stores information on feelings. This therefore shows that different brain areas are responsible for specific functions and behaviours, i.e. the function is localised.

Describe and evaluate Penfield’s study of the interpretive cortex. [9 marks]

Penfield operated on people to treat their severe epilepsy. His technique meant that a conscious patient’s brain was exposed and areas could be electrically stimulated. Patients could then report their thoughts and sensations. With temporal lobe stimulation, patients recalled experiences or recalled feelings associated with the experiences, including experiences of déjà vu. The same memory was recalled each time the same area of the brain was stimulated. This suggests that memories of previous experiences are stored in the temporal lobe. An associated area stores the personal meaning of the experience. Penfield called this the interpretive cortex which is the area that stores information on feelings.

A strength is that Penfield used a very precise method of studying the brain. He could stimulate the exact same area of the brain repeatedly and patients could report their experiences. This enabled him to produce an accurate ‘map’ of brain function.

A weakness is that the participants in the study made up an unusual sample. Participants were all patients suffering from severe epilepsy so It may be that the experience of epilepsy had changed the structure and function of their brains in some way. This could mean that any findings produced were unusual and not reflective of people with nonepileptic brains.

Another weakness is that Penfield’s later research did not always support his original findings. Only 40 of the 520 patients he studied reported vivid memories when their temporal lobe was stimulated. This suggests that the interpretive cortex does not always respond in the same way.

A man fell off a ladder, landing on his head. Afterwards, he experienced memory difficulties and was studied in depth by a psychologist.

1. Explain why a case study would have been suitable to investigate this person’s brain. [2 marks]

People who have memory problems caused by brain damage are rare and so it would be difficult to do an experiment on them as you would struggle to recruit the number of people you needed. Therefore a case study is better.

A man fell off a ladder, landing on his head. Afterwards, he experienced memory difficulties and was studied in depth by a psychologist.

Explain one weakness of using case studies like this one to study topics such as memory. [2 marks]

It is an in-depth study of just one individual. We don’t know what his memory was like before the accident. So the study may not tell us about how all people’s memories work. There are issues with generalising the findings of the study to the rest of the population.

A man fell off a ladder, landing on his head. Afterwards, he experienced memory difficulties and was studied in depth by a psychologist.

Explain how qualitative data could have been collected in this study. [2 marks]

The man’s relatives and friends could have been interviewed as well in order to discover what they observed about his memory before and after the accident.

What is meant by the term ‘cognitive neuroscience’? [2 marks]

Cognitive neuroscience is the scientific study of how biological structures, such as areas of the brain, influence or control mental processes. For instance, research has shown how the hippocampus is linked to the formation of memories in the brain.

Briefly outline how stroke or injury can affect motor abilities and behaviour. [4 marks]

Damage to the motor area through stroke or injury in the left hemisphere will affect movement on the right side of the body, and vice versa. A person with such damage may struggle with fine movements, such as picking up a pen, or more complex movements, such as walking.

Another example of a behaviour that can be damaged by stroke or other injury is language. In most people, the language centres are in the left hemisphere. Damage to these language areas affects the ability to use language. This is called ‘aphasia’ which means an inability to understand or use language.

Describe how the structure and function of the brain relates to behaviour and cognition. [6 marks]

Different structures within the brain control different behaviours. For instance, the frontal lobe includes the motor area which controls and coordinates movement.

The amygdala is an area located deep within the temporal lobe. It plays a key role in processing emotions, such as fear and pleasure in humans and other animals. The amygdala has also been linked to aggressive behaviour.

There is lots of evidence to show that different aspects of memory are located in particular parts of the brain. For example, Tulving’s study suggests that episodic and semantic memories are separate forms of long-term memory. It also seems likely that these types of memory are located in different parts of the brain. When participants thought about semantic memories, there was greater concentration of blood flow towards the back of the brain (the posterior cortex).

Misha is discussing which type of brain scan would be best to investigate the cause of her 5-year-old son’s learning difficulties. Ultimately, she wants a technique that is safe but one that will also give her the most precise images of her son’s brain. She is a wealthy woman who is happy to fund her son’s treatment.

Identify a brain scanning technique to use with Misha’s son and explain the strengths and weaknesses of using it to investigate the cause of her son’s learning difficulties. [5 marks]

An fMRi scan would provide clear images of the brain, which is important as she wants them to be precise.

Images also show the brain in action, which would be important when studying learning processes.

She is a wealthy woman so would be able to afford such an expensive technique.

However, the person having the scan would have to sit very still and a 5-year-old boy may struggle to do this.

In addition, there is a time lag between brain activity and the image appearing on the brain scan, which makes any images lack a little accuracy as they are not produced in real time.

Outline one difference between a PET and an fMRI scan. [3 marks]

One difference is that PET scans use a radioactive substance whereas fMRI scans involve no radioactivity because they measure blood oxygen levels using radio signals.

Explain what is involved in taking an fMRI scan and how it has been used to identify brain functioning. [4 marks]

A person is placed in a scanner and fMRI measures changes in blood oxygen levels in the brain. These are picked up using radio signals and these signals produce 3-D images on a computer screen.

The images produced by fMRI are extremely clear and can show brain activity to the millimetre. This is very useful for seeing in detail what areas of the brain are active whilst a person engages in a certain task

Describe and evaluate CT and PET scans as techniques used to identify brain functioning. [9 marks]

In a CT scan, the brain is examined by taking a large number of X-rays of it. During the scan, the person lies inside a large doughnut-shaped scanner. The scanner is slowly rotated around them so images are taken from many different angles. The images are put together to build up a detailed picture.

CT scans are useful for revealing abnormal structures in the brain such as tumours or structural damage. The quality of the images provided by the CT scan is much higher than that of traditional X-rays.

However, a weakness is that CT scans require more radiation than traditional X-rays, and the more detailed and complex the CT scan is, the more radiation exposure the patient receives. This means that CT scans cannot be used often.

PET scans work by measuring metabolic activity within the brain, so they record which parts are most active. The person is injected with radioactive glucose called a radiotracer. When taken up by the brain, the areas that are most active will absorb more of it and this is sent to a computer.

A strength of PET scans is they show localisation of function. For instance, the person can be asked to look at a picture, solve a jigsaw puzzle, or think about family holidays they went on as a child, and the linked brain area can be identified.

However, a weakness is there are ethical issues to do with the injection of radioactive glucose. Therefore, the technique can only be used a few times.

A psychologist used brain scans to investigate the location of different types of long-term memories in the brain. He interviewed his participants about the terrorist attack on the World Trade Centre in America in 2001. He measured their brain activity in relation to two types of questions: those that related to what they were doing when they heard about the event (episodic memory) and also facts about the event (semantic memory).

1. Write a suitable question that could provide the researcher with quantitative data about episodic memory. Explain why it would produce this type of data. [3 marks]

Do you remember what you were doing when the terrorist attack on the World Trade Centre occurred? Please circle the appropriate response Yes/ No

This would produce quantitative data because it can be counted so you could easily see how many participants remembered what they were doing when the terrorist attack occurred.

A psychologist used brain scans to investigate the location of different types of long-term memories in the brain. He interviewed his participants about the terrorist attack on the World Trade Centre in America in 2001. He measured their brain activity in relation to two types of questions: those that related to what they were doing when they heard about the event (episodic memory) and also facts about the event (semantic memory).

Explain one strength and one weakness of using an interview for this investigation. [2 marks + 2 marks]

A strength is that the researcher can clarify any questions that the participant does not understand. This means that their responses are more likely to accurately reflect their recollection of the events and facts about the attack on the World Trade Centre.

A weakness is that participants may not be truthful as they may say they remember more about what they were doing at the time they heard the news about the terrorist attack than they actually did. This means their answers could be affected by social desirability bias.

A psychologist used brain scans to investigate the location of different types of long-term memories in the brain. He interviewed his participants about the terrorist attack on the World Trade Centre in America in 2001. He measured their brain activity in relation to two types of questions: those that related to what they were doing when they heard about the event (episodic memory) and also facts about the event (semantic memory).

In total 20 questions were asked about episodic memories and on 17 of these there was greater blood flow in the frontal lobe than in the posterior cortex. Express this as a percentage. Show your workings. [2 marks

17/20 × 100 = 85%

Outline the results of Tulving’s ‘gold’ memory study. [3 marks]

Tulving found clear differences in blood flow patterns for three of the six participants.

When participants thought about semantic memories, there was greater concentration of blood flow towards the back of the brain (the posterior cortex). When participants thought about episodic memories, there was greater concentration of blood flow towards the front of the brain (the frontal lobe).

Describe what Tulving’s ‘gold’ study of can tell us about neuroscience. [3 marks]

Tulving’s study is related to neuroscience because it relates brain activity to behaviour. Tulving investigated episodic and semantic memories as separate forms of long-term memory. It also seems likely that these types of memory are located in different parts of the brain – the anterior cortex and posterior cortex. This is related to neuroscience because it supports the idea that memory has a biological basis, and that different types of memory are localised in different areas of the brain.

Describe and evaluate Tulving's 'gold' memory study. [9 marks]

Tulving wanted to see whether episodic and sematic memories were located in different areas of the brain. Six participants were injected with radioactive gold. A repeated measures design was used. Each participant took part in four episodic trials (thought of personal experiences) and four semantic trials (thought of facts). The blood flow in the brain was monitored on a PET scan. It was found that different blood flow patterns were found in three out of six participants. Semantic memories created a greater concentration of blood flow in the posterior cortex. Episodic memories created greater flow in the anterior cortex. This shows that episodic and semantic memories are localised in different parts of the brain and memory has a biological basis.

A strength is that the study produced scientific evidence. This is because it used evidence from brain scans that is difficult to fake, unlike other psychological investigations where you can be less sure that participants are behaving genuinely. This means that Tulving produced unbiased research.

On the other hand, a weakness of the study was that the sample was restricted. There were only six participants in the experiment, including Tulving himself. The differences in blood flow for episodic and semantic memories were seen in only three participants. This means the results were inconclusive as few people showed the same pattern of blood flow, so it is difficult to generalise these findings to all people.

An additional weakness is that episodic and semantic memories are often very similar. Memories for personal events also contain facts and knowledge about the world so it is difficult to work out which type of memory is being studied. This may explain why the evidence from Tulving’s study was inconclusive.