The Biological Approach

What is the biological approach?

A perspective that emphasises the importance of physical processes in the body such as genetic inheritance and neural function.

What does the biological approach suggest?

That everything psychological is at first biological, so to fully understand human behaviour, we must look to biological structures and processes within the body. From a biological perspective, the mind lives in the brain, so all thoughts, feelings and behaviour ultimately have a physical basis.

What is neurochemistry?

It relates to chemicals in the brain that regulate psychological functioning. Much of our thought and behaviour relies on chemical transmission in the brain, using neurotransmitters.

What has an imbalance of neurochemicals in the brain been implicated as?

A possible cause of mental disorder; low levels of serotonin in OCD and overproduction of dopamine in schizophrenia.

How are physiological characteristics, such as intelligence inherited?

In the same way as physical characteristics.

What studies are used to determine whether certain physiological characteristics have a genetic basis?

Twin studies.

How are twin studies used to determine whether certain physiological characteristics have a genetic basis?

By analysing concordance rates - the extent to which twins share the same characteristic.

If a characteristic is genetic, what would we expect?

All identical (monozygotic) to be concordant, as they share 100% of the same genes, but this would not be true for non-identical (dizygotic) twins who share about 50% of the same DNA. In both cases, the environment is assumed to be constant.

What is genotype?

The particular set of genes that a person has.

What is phenotype?

The characteristics of an individual determined by both genes and the environment.

What is the difference between genotype and phenotype?

A person’s genotype is their actual genetic make-up, while phenotype is the way that genes are expressed through physical, behavioural and psychological characteristics.

Do twins always express their genes in the same way?

Despite having the same genes, the way identical twins’ genes are expressed is different, illustrating what many biological psychologists would accept, that much of human behaviour depends upon an interaction between inherited factors (nature) and the environment (nurture).

What is evolution?

The changes in inherited characteristics in a biological population over successive generations.

What did Darwin propose to explain evolution?

The theory of natural selection. The main principle is that any genetically determined behaviour that enhances an individual’s survival and reproduction will continue in future generations (be naturally selected). This is ‘natural‘, as no one decides this.

Why does natural selection occur?

Simply because some traits give the possessor certain advantages. The possessor is more likely to survive, reproduce and pass on these traits. If the individual survives but does not reproduce. the traits do not remain in the gene pool for successive generations.

What are the strengths of the biological explanation?

• Real world application.

• Scientific methods.

How is real-world application a strength of the biological method?

Increased understanding of neurochemical processes in the brain is associated with the use of psychoactive drugs to treat serious mental disorders. For example, the biological approach has promoted the treatment of clinical depression sing antidepressant drugs that increase levels of serotonin at synapses in the brain. Such drugs have been associated with the reduction of depressive symptoms.

What does the real-world application mean for the biological approach?

That people with depression may be better able to manage their condition and live their lives in the community, rather than remain in hospital.

What is the counterpoint to the real world application?

Although antidepressant drugs are successful for many patients, they do not work for everyone. A recent study by Ciprani et al. compared 21 antidepressant drugs and found wide variation sin their effectiveness. Although most of the drugs were more effective than placebos in comparative trials, the researchers concluded that the effects of antidepressants in general were ‘mainly modest‘.

What does the counterpoint to the real-world application mean?

It challenges the value of the biological approach because it suggests that brain chemistry alone may of account for all cases of, for example, depression.

Why is scientific methods a strength of the biological approach?

In order to investigate the genetic and biological basis of behaviour, the biological approach makes use of precise and highly objective technology. These include scanning techniques such as fMRIs and EEGs. With advances in technology, it is possible to accurately measure physiological and neural processes in ways that are not open to bias.

What does the use of scientific methods mean for the biological approach?

That much of the biological approach is based on objective and reliable data.

What is the limitation of the biological approach?

Biological determinism.

How is biological determinism a limitation of the biological approach?

It is determinist; is sees human behaviour as governed by internal, genetic causes over which we have no control. However, the way in which a person’s genotype is expressed is heavily influenced by the environment. Not even identical twins who share the same genes look and think the same. A purely genetic argument also becomes problematic when we look at crime. Could a violent criminal excuse their actions by claiming their behaviour was controlled by a crime gene?

What does the biological determinism mean?

It suggests that the biological view is often too simplistic and ignores the mediating effects of the environment.