The biological approach Flashcards
What does this approach see behaviour being rooted in?
The physiology and biology of the body, including the processes that occur
What are the three core assumptions of the biological approach?
Behaviour is affected by:
- Genetics
- The central nervous system
- The chemistry of the body
What is a genotype?
The genetic make-up of an individual, which occurs at conception
How many genes is each individual thought to have?
Around 10,000
Give an example of a characteristic that a genotype affects
Hair and eye colour
What is a phenotype?
The characteristics that are shown by an individual that occur through genes interacting with environment
Give an example of a phenotype
Height: The genotype relates to genetic instructions, such as having the potential to be tall, but if the environment does not provide the optimum conditions then the individual will not fulfil this potential, making the height they actually become their phenotype
How many pairs of chromosomes is an individual typically born with?
23
What type of twins are used in studies of genetics and why?
Monozygotic because they share 100% of their genes, so a concordance rate can be established
How much genetic material do dizygotic twins share?
50%
When do twin studies argue that there is a genetic component?
If the MZ twins show a higher likelihood of sharing behaviours/disorders than DZ twins
What does concordance rate mean in twin studies?
The amount of shared behaviour
How does evolution shape human behaviour?
- A random mutation in the genetic make-up of an individual occurs that changes behaviour or characteristics of that individual
- If that change means that the chances of survival/reproduction are reduced the gene is not passed on, but if it increases these chances the mutation is passed to the individual’s offspring (adaptive value)
- The gene becomes common within the species,although this occurs over many generations
Why do biological psychologists believe that examination of non-human behaviours is useful?
The behaviour in animals occurs in a similar evolutionary process as humans
Give an example of an animal behaviour that is widespread and adaptive, and can also be found in humans?
Aggression: Increases access to resources, protects territory and aids finding a mate
What genetic basis of aggression have biological psychologists found and how common is it?
MAOA (warrior gene), found in one third of men (Lea et al.)
What are the three key biological structures that are useful in explaining human behaviour?
- The nervous system
- The neuron
- The endocrine system
What is the nervous system divided into?
The central and peripheral nervous systems
What is the central nervous system?
The brain and spinal cord; transfers messages to and from the environment and acts as the centre from which all physiology of the body is controlled, and most actions and reactions are generated from the CNS
What is the peripheral nervous system?
Sends and receives information to and from the central nervous system and collects information from the environment. The autonomic nervous system is important for survival and affects reaction to the threat. The somatic system comprises the muscles attached to the skeleton and is therefore important for movement
What is a neuron?
A nerve cell which transfers information between the nervous systems. There are billions within the human body and their structure varies depending on their function
What is the endocrine system’s job?
To maintain hormone levels in the blood and other bodily fluid by using glands within the body, the most important of which is the pituitary
Why is the pituitary gland nicknamed the “master gland”?
It instructs the other glands to secrete hormones when necessary
What is neurochemistry?
The biochemistry of the central nervous system; the chemicals that travel around the brain are called neurotransmitters, and are thought to affect behaviour
Give an example of neurochemistry affecting behaviour?
High levels of a neurotransmitter called dopamine is linked to schizophrenia
How can the biological approach be criticised?
- Too simplistic and do not do the complexity of human behaviour justice
- Supports the nature side of the nature-nurture debate
What are the strengths of the biological approach?
- It uses scientific and objective methods of investigation, e.g. brain scans and biochemical levels
- Practical applications such as drugs that help symptoms
What is the difference between the central and peripheral nervous systems?
- Different functions - One controls response, the other provides information
- Different areas of control - Brain and spinal cord, muscles and sensory neurones
What is the genome project?
An assessment of behaviour is made and then your geneology is cross-referenced with everyone else in the database to compare your behaviour with other people who contain the same gene to find similarities in behaviour. This has allowed biologists to pinpoint genes responsible for behaviour
