Biological Approach

This section explores The Biological Approach in Psychology. The Biological Approach in psychology examines how our biology: specifically our genes, brain structures, and neurochemical processes; influences behaviour. This approach assumes that behaviour and mental processes have a physical basis and are influenced by our genetic makeup, neural structures, and evolutionary history.

Key Concepts in the Biological Approach

The Influence of Genes on Behaviour

Genes are units of heredity, made of DNA, that are passed down from one generation to the next. They carry the instructions for the development of both physical and psychological traits.

According to the biological approach, much of our behaviour, personality, and cognitive abilities are inherited from our parents, influenced by specific genes.

Genetic Basis of Behaviour:

Psychologists study how certain genes may predispose individuals to certain behaviours or mental health conditions, such as schizophrenia, depression, or anxiety.

Twin studies and family studies are commonly used to investigate the genetic basis of behaviour by comparing concordance rates (the likelihood that both twins will exhibit a particular trait). Higher concordance rates in monozygotic (identical) twins compared to dizygotic (non-identical) twins suggest a genetic influence.

Example:

Schizophrenia: Studies have shown higher concordance rates for schizophrenia among identical twins than fraternal twins, indicating a genetic component to this disorder.

Biological Structures and Behaviour

The brain, as the central organ of the nervous system, plays a critical role in behaviour and mental processes. Different areas of the brain are associated with specific functions.

Key Brain Structures:

• Cerebral Cortex: Responsible for higher-order functions like thinking, planning, and problem-solving.
• Limbic System: Involved in emotions and memory, with structures like the hippocampus (memory) and amygdala (emotion).
• Hypothalamus: Regulates essential bodily functions, including hunger, thirst, and stress responses.

Damage to specific brain areas can lead to changes in behaviour and personality. For example, damage to the frontal lobes can impair decision-making and impulse control, while damage to the hippocampus can affect memory.

Neurochemistry and Behaviour

Neurochemistry refers to the chemicals within the brain that influence how neurons communicate and, consequently, affect behaviour.

Neurotransmitters: Chemical messengers that transmit signals between neurons. Different neurotransmitters are associated with different effects on mood, behaviour, and mental health.

Serotonin: Linked to mood regulation. Low levels are associated with depression.

Dopamine: Associated with reward and pleasure. Imbalances are linked to conditions such as schizophrenia (excess dopamine) and Parkinson's disease (deficient dopamine).

GABA (Gamma-Aminobutyric Acid): Acts as an inhibitory neurotransmitter, helping to calm neural activity. Low GABA levels are linked to anxiety disorders.

Hormones: Chemical messengers released into the bloodstream by glands in the endocrine system that also influence behaviour. For example:

Adrenaline: Prepares the body for a 'fight or flight' response during stressful situations.

Cortisol: Released in response to stress; chronic high levels can negatively affect health and mood.

Genotype and Phenotype

Genotype: Refers to an individual's genetic makeup—the specific set of genes they inherit from their parents. This genetic blueprint provides the potential for certain traits, behaviours, and characteristics.

Phenotype: Refers to the observable characteristics or behaviours that result from the interaction between an individual’s genotype and their environment. While genotype provides the potential, phenotype is how those genes are expressed in real life.

Example:

Height: A person may have a genotype that codes for tall stature, but if they grow up in an environment with poor nutrition, their phenotype (actual height) may be shorter than the genetic potential.

Similarly, someone may have a genetic predisposition for high intelligence (genotype), but environmental factors, like access to education, will affect the actualisation of that potential (phenotype).

This distinction highlights that while genetic predispositions play a significant role, the environment also has a powerful influence on how these predispositions are expressed.

Evolution and Behaviour

The biological approach also draws on evolutionary theory to explain how certain behaviours may have developed over time to enhance survival and reproduction. This aspect of the approach is based on Charles Darwin’s theory of natural selection, which posits that traits enhancing an organism’s survival and reproductive success are more likely to be passed down to future generations.

Natural Selection and Adaptive Behaviours

According to evolutionary psychologists, behaviours that offered advantages in the survival and reproduction of our ancestors became ingrained in the human species.

For example, behaviours associated with mate selection (like males displaying dominance or females being selective in choosing partners) may be seen as evolutionarily adaptive.

Examples of Evolutionary Behaviours

Attachment: Bowlby suggested that infants are biologically predisposed to form attachments with caregivers as a survival mechanism, increasing their chances of protection and sustenance.

Aggression: Some psychologists propose that aggression may be an evolutionary behaviour for securing resources and defending territory or mates, increasing survival and reproductive success.

Phobias: Evolutionary theory suggests that phobias (e.g., fear of heights, snakes) may stem from ancient threats that posed risks to human ancestors, helping them to avoid potentially dangerous situations.

By considering evolutionary factors, the biological approach provides insight into why certain universal behaviours exist across cultures and persist despite changes in modern society.

Evaluation of the Biological Approach

The biological approach has contributed significantly to our understanding of human behaviour, offering valuable insights into the links between biology and psychology. However, it has its strengths and limitations.

Strengths

• Scientific and Objective: The approach uses rigorous scientific methods, such as brain scans, genetic testing, and biochemical analysis, providing reliable and objective data.
• Applications: Findings from the biological approach have led to practical applications in medicine, such as drug treatments for mental health conditions like depression, schizophrenia, and anxiety.
• Strong Support from Empirical Evidence: Studies on genetics, neuroanatomy, and neurochemistry offer robust evidence supporting the influence of biology on behaviour.

Limitations

• Reductionist: The approach may be criticised for oversimplifying complex behaviours by reducing them to biological factors, potentially overlooking the role of social and environmental influences.
• Deterministic: The biological approach suggests that behaviour is largely predetermined by genetics and biology, implying a lack of free will, which may not account for the full range of human experience.
• Ethical Issues in Research: Genetic research, in particular, raises ethical concerns, especially concerning genetic predispositions to certain behaviours and the potential for misuse of this information.

Summary

The Biological Approach in psychology emphasises the influence of genetics, brain structures, and neurochemistry on behaviour, recognising the role of evolutionary history in shaping behaviour. By exploring the interaction between genotype and phenotype, the biological approach provides valuable insights into the complexities of human behaviour and mental processes. Despite criticisms of reductionism and determinism, this approach has offered considerable advancements in the understanding and treatment of psychological disorders and remains a foundational perspective in psychology.