Biological psychology

Question 1

Describe the role of the central nervous system in human behaviour.

Answer 1

• Composed of the brain and spinal cord
• Spinal cord- recieves information from the skin, joints and muscles
• Brain- processes and interprets the sensory information from the spinal cord and then sends it to the muscles
• Neurons- motor, inter and sensory that all pass messages using electrical impulses

Question 2

Describe the parts of a neuron and how neurotransmitters have a role in human behaviour

Answer 2

• Dendrites- collects information from other cells and recieves messages in order to trigger an action potential
• Nucleus- site of aerobic respiration
• Axon Hillock- where the impulses are triggered from
• Myelin Sheath- layers of fatty deposit that provide an insulating layer and help to speed up the rate of message transmission
• Axon- transmits information away from the cell body towards other neurons
• Schwann’s cells- the cells that make up the long cell chain
• Terminal buttons- contains the vesicles that store neurotransmitters ready for the next stage of neurotransmission
• Axon terminals- transmitters
• Action potential- inside is negatively charged, when stimulated positive particles enter, some of these then get pushed out and the neurone goes back to negative
• Chemical transmission accross a synapse

Question 3

Describe the effect of recreational drugs on the central nervous system.

Answer 3

Nicotine- a toxic, colourless liquid that is found in tobacco and is highly addictive. The short term effects of the drug include increased blood pressure, increased pulse and a release of dopamine. Nicotine imitates the action of acetylcholine and binds to the acetylcholine receptors. An action potential is triggered and it stimulates the release of dopamine. Once tolerance is built up, it is required to maintain normal levels of dopamine.

Alcohol- short term effects include aggression, slowed reflexes and thought processes and personality changes. Alcohol affects GABA which increases serotonin and dopamine. It lowers the frequenc of action potentials which causes slowed reactions. Withdrawal symptoms include agitation, fever and hallucinations.

Heroin- gets broken down in to morphine in the body which binds to receptors causing a reduction in neurological activity and releases dopamine. The effect of the drug include slowed breathing, drowsiness, dry mouth and vomiting. If a high level of tolerance is built up and then the drug is stopped, there could be serious side effects.

Question 4

Evaluate the effect of drugs on the central nervous system in terms of generalisability.

Answer 4

Lots of the research is done on animals as it would be too unethical to complete on humans. To an extent, animals have a very similar brain structure to humans however humans are far more complex and capable of higher order thinking and reasoning. Therefore, the research can be seen to lack generalisability.

Question 5

Evaluate the effect of drugs on the central nervous system in terms of reliability.

Answer 5

High in reliability as most research is carried out in the laboratory using highly scientific medical testing or scans. This means that high levels of control can be obtained and so the research will follow a standardised procedure. This means that the research is replicable and so supports findings.

Question 6

Evaluate the effect of drugs on the central nervous system in terms of validity.

Answer 6

High level of validity due to the highly scientific and objective measures used. PET scans are a scientific and objective way to study the brain. This allows for high control over extraneous variables and so a cause and effect relationship can be established.

Question 7

Evaluate the effect of drugs on the central nervous system in terms of supporting studies.

Answer 7

Support comes from withdrawral symptoms. They demonstrate the fact that the brain relies on the drugs once youve started to take it. Everytime the drug is taken, tolerance to it is built up and failing to take it results in the physical symptoms.

Further support can be seen by Li et al who looked at heroin addicts.

Question 8

Describe the role of evolution and natural selection to explain human behaviour.

Answer 8

• Males produce thousands of sperm at relatively little physiological cost; as such, their best strategy is to mate with as many females as possible as this will result in the maximum number of offspring to perpetuate their genetic line
• Female investment in her offspring is greater than male investment partly as a result of the physical and emotional efforts of pregnancy. Therefore females might be more discriminatory in their choice of partner.
• The purpose of relationships and attraction is to reproduce and ensure our genes are passed on. Men and Women should seek partners who will produce healthy offspring who can be cared for. This explains why men prefer young women and women prefer wealthy men.
• Women can only bear a limited number of children and they can invest in each very heavily during pregnancy and the years after. Therefore this explains why women are picky about who they mate with.
• Females might be attracted to males with features that have survived as it makes it more likely that her offspring will survive.

Question 9

Describe the role of evolution and natural selection to explain aggression.

Answer 9

• ‘Aggression is an innate response’ suggests that humans are aggressive because of the process of natural selection. It is suggesed that our ancestors passed on their aggressive traits to their offspring through their genes.
• Aggression is often associated with males. Males are motivated to acquire status as this allows them to have access to mates and resources for survival. Not engaging in conflict with other males may therefore be costly as they will not be able to reproduce.
• Females are generally seen as less aggressive since for them, the costs of such behaviour outweighs the benefits. It is more important for the mother to survive as she helps the offspring to survive

Question 10

Describe how different brain areas can be an explanation for aggression

Answer 10

• The prefrontal cortex is involved in planning, control and organisation. It regulates the amygdala and so also regulates the aggressive thoughts and actions. It plays a part in assessing any potential threats and helps to determine a rational response.
• The amygdala has a functional role in memory, emotion and fear. Damage to the amygdala causes a reduction in automatic arousal which leads to reduced emotional responses and fearlessness. Strong links with the fight or flight response.
• The hypothalamus releases seratonin in order to communicate with the pituitory glands. It does this to stop too much testosterone from being released.
• The hippocampus is associated with aggression and plays a role in forming episodic memories. This suggests that whilst we are able to make and learn from our memoies ordinarily, if this part of the brain is damaged we still can make new memories but are no longer able to learn from them.

Question 11

Evaluate the role of brain areas in aggression in terms of supporting research.

Answer 11

• Prefrontal cortex- Phineas Gage suffered from damage to this area. He suffered personality changes and went from being a calm and kind person to someone who was aggressive and short tempered. This demonstrates the importance of this area
• Amygdala- Raine et al found that murderers who pleaded not guilty by reason of insanity had lower glucose metabolism in the left side of the amygdala and higher metabolism in the right which deals with emmotions. This suggests a higher emotional response which is shown as aggression.
• A study by Alpars found that an individual who had a tumour growing on this part of the brain had a personality change to become aggressive

Question 12

Evaluate the role of brain areas in aggression in terms of criticisms of the supporting research.

Answer 12

• Research in to brain structure and functioning happens in the laboratory. This is a highly objective research method and the use of scans is highly scientific. Therefore it is possible to gain control over extraneous variables and maintain a cause and effect relationship.

Question 13

Evaluate the role of brain areas in aggression in terms of criticisms of the research method.

Answer 13

• Lots of the research is animal research as this allows us to overcome ethical and practical issues. It can be argued that the limbic system in animals functions similarly to humans. Therefore it can be argued to have some generalisability. On the other hand, humans are much more complex and have more complex brain structures, this may limit the generalisability and usefulness of the research.

Question 14

Evaluate the role of brain areas in aggression in terms of other points.

Answer 14

• Can be seen to be reductionist as it fails to take in to consideration social factors that could impact upon aggression such as the specific situation that an individual finds themself in. Therefore the theory lacks validity.

Question 15

Describe the role of the psychodynamic approach on aggression.

Answer 15

• id- the part of the subconscious that is concerned with things that ensures the survival of a person and with the things that gives us pleasure. These demands need to be satisfied by all instincts immediately and at all costs.
• superego- develops to help us to know what is right from wrong and what we should/shouldn’t do to help us to fit in to society. A weak superego may develop if you have low expectations of yourself as a child.
• ego- aims to satify the demands of the id without conflicting the superego.
• In aggression, the id is the most dominant and it makes selfish demands that are hard to please.
• A harsh superego can lead to strong feelings of guilt and obsession whenever the id attempts any kind of satisfaction. Dealing with the overiding feelings of guilt can lead to aggression. If the urges are overwhelming aggressive behaviour may be displaced on to others.
• Catharsis- an emotional release of unconscious conflict

Question 16

Evaluate the role of the psychodynamic approach on aggression in terms supporting research.

Answer 16

Support comes from everyday experiences as they support the idea of defence mechanisms. They effectively explain how we make ourselves feel better when we experience potentially psychologically damaging situations such as failing an exam.

Question 17

Evaluate the role of the psychodynamic approach on aggression in terms criticisms of the research.

Answer 17

• Freud’s concepts were not measurable because he looked at the unconscious. This is unreachable by normal means and as a result the concepts studied lack scientific credibility as a cause and effect relationship can’t be established.
• The research method most commonly used by Freus was case studies. This is a disadvantage because the data is completely qualitative. This means that the data is subjective and lacks scientific credibility as it is impossibe to establish a cause and effect relationship
• Freud drew his conclusions from a small sample of case studies mainly of middle class Viennese women. His sample was bias in terms of both gender and class. This makes it very hard to generalise the results as it can’t be said taht they are representative of the whole population.

Question 18

Describe the role of hormones on human behaviour.

Answer 18

• Hormones regulate sexdrive, body regualation mechanisms including temperature and can affect our body either directly or indirectly
• Hormones and neurotransmitters are very similar but have a few key differences in terms of the speed at which they can take effect and the length of time that the change happens for.
• Testosterone is found in both males and females but in highr levels in males. It is generally accepted that men are more aggressive than women. Testosterone is thought to have links to language, aggression and cognitive abilities.
• Cortisol is a steroidal hormone responsible for blood glucose regulation, immune functions and anti-stress responses. It is released under stressful conditions and is responsible for the fight or flight response. Low cortisol means high aggression

Question 19

Evaluate the role of hormones in explaining aggression in terms of generalisablity.

Answer 19

• The hypothalamus and limbic systems in humans in humans and rodents are similar enough to allow for generalisations to be made. There are also shared genes between animals and humans that make generalisations more valid.
• Although mice and humans share more than 90% of their genes, there are sufficient differences between them to suggest that findings about aggression in mice can’t be generalised to humans

Question 20

Evaluate the role of hormones in explaining aggression in terms of criticisms of the research.

Answer 20

In humans the data tends to be correlational data meaning that cause and effect conclusions can’t be established. There are links found between cortisol and aggression but what is not known is whether there is another variable involved.

Question 21

Describe the role of evolution and hormones in human development.

Answer 21

• Ethologists see behaviours such as aggession as being biologically programmed because it is needed. Human behaviours exist today because they aided our survival.
• Infidelity and jealousy may lead to aggression. A women may become jealous if the man is with another women because she feels that his role is to protect feed and shelter any of her children.
• We compete in life to pass on our genetic information. Females will always pass on their genes however males do not.
• Hormones are also important for regulating sexual function. Testosterone is particularly important.

Question 22

Describe the role of brain functioning as an explanation for aggression

Answer 22

• Seratonin is an important chemical neurotransmitter in the human body. It is commonly regarded as a chemical that is responsible for maintaining mood balance .
• Serotonin reduces aggression by preventing stimulation of the amygdala. This increases aggressive behaviour but seratonin prevents stimulation thereby reducing aggression
• If someone is suffering from low levels of seratonin in the brain there is less inhibition of the amygdala. As a result it becomes more active when stimulated by eternal events causing a person to act on their impulses and therefore making aggression more likekly. Therefore low levels of seratonin have been associated with an increased susceptibility to impulsive and aggressive behaviour.
• Dopamine is another neurotransmitter, one associated with the feelings of pleasure and motivation. Increased dopamine levels have been found to increase levels of aggressive behaviour. As dopamine levels increase, seratonin decreases

Question 23

Evaluate brain functioning in aggression in terms of supporting research.

Answer 23

Ferrari et al (2003) provides support for the dopamine hypothesis. He studied the link between neurotransmitters and aggression in rats. They allowed rats to fight everyday for ten days before introducing an intruder rat on the eleventh day. Researchers measured the levels of seratonin and dopamine. As dopamine increased, seratonin decreased.

There is support for the role of seratonin from Mann et al. They gave participants the drug dexfenfluramine which depletes levels of seratonin in the brain. The researchers then used a questionnaire to assess hostility and aggression levels. This was found to be raised after taking the drug. Therefore this provides support for decreased seratonin leading to aggression.

Question 24

Evaluate brain functioning in aggression in terms of criticisms of the supporting research.

Answer 24

Scanning is a highly reliable research method. By using PET, CAT and fMRI scans, more precision can be gained in comparison to earliertechniques. A great depth and a high level of detail can be obtained and studied. Brain structures can be isolated and measured which therefore increases the validity of the results.

Question 25

Evaluate brain functioning in aggression in terms of generalisability.

Answer 25

Although neutral mechanisms are similar between animals and humans, humans exhibit much more executive functioning and higher order thought processes than animals. Animals do not have to abide by moral and criminal laws. In animals, aggressive behaviours might be necessary for survival and reproduction. Therefore there are issues with generalisability.

Question 26

Describe individual differences in biological psychology.

Answer 26

• Studies in to brain damaged patients seem to assume that prior to the brain damage, everyone’s brains were much the same- the differences seen during the collecting of data during the study period are as a result of the brain damage and were not there previously. With very few exceptions the mental conditions of the patients prior to brain damge is not known so we therefore tend to assume that any abnormal behaviour is as a result of the brain damage
• Individuals may also respond differently in terms of brain damage. The damage caused to an individual for exampleby a stroke, will affect people in different ways.
• Alpers had a localised tumour. He found that a tumour on the hypothalamus which affected the transmission of communications with the pituitory gland. This meantthat a large amount of testosterone was released.
• Phineas Gage suffered damage to his prefrontal cortex. Before his injury he was happy, helpful and a nice person. He was involved in an accident where a metal accident shot through his head. This caused damage to his prefrontal cortex and caused him to become angry, aggressive and grumpy.
• According to Freud, individual differences exist due to the parts of the personality. The id is the primitive biological partof the mind and this part of the personality is present from birth as it relates to our basic needs. The ego aims to satisfy the desires in line with what is realistically possible. The superego is the part of the brain that judges if actions are right or wrong. This part of the personality develops as we learn moral rights and wrongs as we develop.
• Some people might be more aggressive than others as they have an overpowering id and a weak superego. A weak superego maybe a result of an absent parent.