The importance of Biology within the field of psychology has been and continues to be widely debated. Some scientists such as Francis Crick, believe that explanations for psychological differences can only be found by the means of studying the biology of the brain and genes, this belief is known as reductionism. However most psychologists now believe that biology and psychology go hand in hand and that both need to be considered; the biology and the social context, to be able to come to a more accurate explanation.
In this essay I will look at how biology contributes to understanding behaviour and look at examples of this. Depression is a key example of how biology and psychology inter-linked can be the cause of changes in mood and behaviour. Depression is an illness that makes a person feel very ‘low’ in mood and often tired, irritable, anxious and antisocial. It causes a change in their behaviour; they isolate themselves from other people and it can cause behaviours such as self harm, obsessive behaviours and suicidal behaviours. Biology seems to show that depression is caused by abnormalities in neurotransmission at synapses.
Neurotransmitters are specific chemicals released from a neuron, which travel across neuron synapses to specific receptor sites. Low levels of neurotransmitters at synapses, have been found to cause low mood and depression. The re- uptake of the neurotransmitter into the synapse causes the neurotransmitter to become inactive. This means the level of the chemical messenger at the synapse is lowered, causing low mood. Anti- depressants such as Prozac act as re-uptake inhibitors; blocking re-uptake and so increasing the amount of neurotransmitter at the synapse.
It is also believed by biologists that depression may be an inherited condition passed down in the genes. However traumatic events are also known to affect the nervous system and can cause these biological differences. In some cases it may be to do with inheritance/biology, but it can also be to do with people being exposed to certain levels of stress, traumatic events and differing life experiences. Biology doesn’t explain why anti- depressants work for some people and not others.
Treatment often involves dealing with biology and psychology through means of anti- depressants and therapy. Pleasure drugs such as alcohol, heroin and nicotine can also affect mood and behaviour. They all affect the nervous system and activity levels at the synapses which is known to affect mood. Alcoholics tend to have lower levels of the neurotransmitter serotonin in their central nervous system and alcohol temporarily increases these levels, which can cause risk taking behaviour, make the person more confident and also cause over anxiety. The low level of serotonin in alcoholics and the ‘high’ they then experience may be why they become addicted to this drug-like substance.
This is very similar to drugs such as cocaine. Cocaine “blocks the re-uptake of dopamine and thereby increases the amount of dopamine at synapses. ” (Mapping Psychology 1, p258). After taking the drug; users describe a period of euphoria, reflecting the increase in levels of the neurotransmitter at the synapses. When the levels of neurotransmitter at the synapse decreases rapidly it then creates a feeling of dysphoria in the user causing low mood. This shows how certain drugs can in effect alter the biology of our bodies, to affect mood and behaviour.