What makes humans different from animals? How can we explain the individual differences in our species? Although biological psychologists argue that behaviour may be explained by evolution, development, genetics and physiology, social psychologists have commented upon the influence of social, emotional, cognitive and psychological changes when interpreting behaviour. Therefore, with the use of examples, this essay will attempt to show that while much of the understanding human behaviour may stem from a biological perspective; other psychological influences are also responsible for modifying human behaviour patterns.Further, this essay will attempt to highlight that biology is not a deterministic process and that an interaction between biology and psychology results in behaviour patterns. Psychologists have theorised explanations for a variety of mental illnesses including depression.
A biological explanation has been proposed that imbalances in synaptic neurotransmitters such as serotonin may manifest with depressive symptoms. This proposal has been supported by the beneficial effect of anti-depressant drugs which act by increasing the level of serotonin at synaptic clefts (Toates, 2002, p. 251).However, while these antidepressants are said to take 2-5 weeks on average to achieve a therapeutic level, they do not seem to work for everyone. Indeed, patients using these drugs have reported changes in their moods far earlier (Holsboer, F.
& Barden, N. , 1996). These findings suggest that there may be additional elements besides a purely biological viewpoint contributing to the causes and relief of depression. This is supported by suggestions that although a person may be genetically susceptible for depression, environmental and lifestyle changes may cushion him against developing such an illness (Toates, 2002, p. 76).
This view conflicts with the determinist view and highlights the interaction of biology and psychology. In contrast, extreme stress events such as trauma may lead to this illness in the absence of an overt genetic component (Toates, 2002, p. 276).Thus while eminent figures such as Crick (Toates, 2002, p. 228) have used the reductionist viewpoint by suggesting that psychological events and experiences may be explained by a neuronal/biochemical basis, the value of psychological counselling acting synergistically with formal anti-depressant medication to improve depression (Toates, 2002, p. 84) further emphasises the interaction of biological and psychological processes.
In this way, levels of analysis from both viewpoints are used. Of interest is that while most would fail to see the benefit of a depressive illness, the biological perspective proposes that an evolutionary advantage is gained by attracting sympathy and therefore assistance or by deflecting potential conflict. Biological processes attempt to achieve homeostasis.While drugs such as anti-depressants attempt to return chemical imbalances to normal levels, others such as cocaine have been used for recreational purposes to achieve states of euphoria by creating chemical imbalances. While this is a purely biological explanation, the initial taking of the drug often belies psychological influences arising from environmental factors such as peer group pressure or concomitant work stresses. Once an individual has experienced a 'high', this is subsequently followed by a 'down' which is the body's 'displeasure response' to a deviation from the homeostatic norm that cocaine had reset to (Toates, 2002, p.
58).In turn, an evolutionary survival response is then triggered for an individual to negate the 'down' feeling by replacing cocaine levels. While individuals adapt to environments in order to achieve a biological homeostasis, in the case of drug-abuse this is often manifest in maladaptive behaviour which results in psychological changes in behaviour e. g. an addict may lose concentration abilities and lose a job and may subsequently be drawn into crime to obtain further supplies.
This in turn by altering their environment may reciprocally affect their behaviour further. The examples above of drug addiction and depression have concentrated upon the physiological mechanisms involved in respect of a biological perspective. However, while the genetic contribution is poorly understood when compared with conditions such as Schizophrenia (Gottesman and Moldin, 1998), further research, perhaps using data from the Human Genome project, is required to assess a genetic link with the susceptibility of individuals to these mental illnesses.This research will of course be limited ethically as epidemiological data may only be collected as individuals may not be e. g. randomised into drug and non-drug taking groups.
Cerebral lesions arising from trauma or other physiological processes such as a stroke have been noted to alter behaviour in humans. For example, the literature reports the case of Phineas Gage who suffered trauma to his left frontal lobe resulting in an alteration in his behaviour with no change in his linguistic or intellectual abilities. Toates, 2002, p. 266).These types of abnormalities in the brain cause dysfunction and by understanding the limitations in physical, cognitive, psychological or social behaviour the damaged area may be located.
By using techniques such as PET (positron emission tomography) scanning, psychologists have been able to analyse areas of brain activity or inactivity (Toates, 2002, p. 268). Thus, they have used inductive thinking to associate a behaviour pattern with an area of brain inactivity and link this to the biology.However, while PET scanning is a revolutionary tool for brain imaging, the inferences made are not free of scientific scrutiny. For example, brain injuries are often unique and therefore a case series may not be arrived at. Further, injuries are not likely to occupy one clear functional segment of the brain and the effect of damaging adjacent brain areas may confuse any subsequent interpretations and also restorative neuronal growth may occur.
Contrastingly, such injury rather than damaging a functional brain element may be actually disrupting brain connections (Toates, 2002, p. 67). While such outsider evidence exists, complimentary insider findings are harder to arrive at. Although, PET scanning may be used while participants are asked questions, ethical considerations mitigate against replicating many animal experiments. With time, the advent of future investigative technologies may improve researcher's abilities to facilitate such insider scenarios.
In conclusion, behaviours may have a genetic basis to alter physiology and the functioning at the synapses of the brain.Although, impairments between the links of these synapses may be crucial for human behaviour it cannot exclude the psychological and social factors completely. As highlighted above, stressful life events have been shown to exacerbate mental illnesses such as depression and drugs used to treat depression are not universally efficacious. Many of these behaviours require a social context for altered behaviours.
Thus, while a biological perspective is important in interpreting aspects of behaviour, it appears that interactions involving psychological and social factors such as life events and environments are also involved.
