Biological Approach Flashcards
Define Biological Approach to Psychology
Focuses on genetics neurochemistry, the nervous and endocrine systems and evolution of behaviour.
The Influence of genes on behaviour
Genes carry the instructions for a particular characteristic. Heredity is the passing of characteristics from one generation to the next through the genes. The argument about the relative contribution of genes and environmental influences to characteristics is called the nature-nurture debate.
Define Genotypes
The unique genetic code that comprises an individuals DNA
Define Phenotypes
The Physical expression of the genotypes
Define Heritability
is the amount of variability in a trait in a population that can be attributed to individual genotypic differences. Studies of identical twins suggest that 60% - 80% of the variability in intelligence could be genetic
The influence of biological structures on behaviour around neurons and the nervous system
Nervous systems transmit impulses via nerve cells (neurons).
They comprise:
The central Nervous System (The Brain and spinal Cord)
The Peripheral Nervous System(The somatic and autonomic nervous systems)
The influence of biological structures on behaviour around the brain
The cerebrum makes up about 85% of the brain and is divided into two hemispheres each with four lobes. Its outer surface, the cerebral cortex, is responsible for ‘higher-order’ functions such as thought and language
The Influence of neurochemistry on behaviour
Nerve impulses travel between neurons via the synapse by means of neurotransmitters. Some are excitatory (Dopamine) and others inhibitory (serotonin)
The influence of Hormones on behaviour
Hormones are chemicals produced by glands (the pituitary gland) comprising the endocrine system. The brain signals glands to release hormones directly into the bloodstream and stimulate receptors on ‘Target Cells’ to alter their activity.
Evolution and Behaviour
Darwin argued that individuals who have physical and behavioural characteristics that enable them to survive and reproduce pass them to the next generation. Through this process of evolution by natural selection, successive generations become better adapted to their environment.
Strengths: The importance of the scientific method
Scientific method allows biological psychologists to replicate research to their soundness
Strengths: Applications of the biological approach
Research into neurochemical imbalance in depression has led to effective drug treatments. Research into circadian rhythms has led to a better understanding of the psychological impact of shift work.
Limitations: The biological approach is reductionist
Neurochemical and hormonal explanations of mental disorders are reductionist and arguably ignore cognitive, emotional and cultural influences.
Limitations: The dangers of genetic explanations
Genetic Explanations of behaviour may be poorly understood and potentially abused, eg screening could identify those with a genetic predisposition for criminality but underplay the complexity of causes leading to discrimination.
