Approaches: biological approach

Question 1

assumptions of the biological approach

Answer 1

• everything psychological was at first biological
• human are biological organism so to understand human behaviour we must look at biological structures
• ur mind lives in ur brain (all thoughts, feeling and behaviours have a biological basis)
• genes influences behaviour
• behaviour evolves the same way as physical characteristics
  > through processes of evolutionary adaption

Question 2

influence of genes on behaviour

Answer 2

def: the mechanisms of heredity

• this is the passing of characteristics from one generations to the next through genes
• genes carry the instructions for particular characteristics, but how this characteristics develops depends on the interactions of the gene with other genes (or the environment)

the extent to which psychological characteristics is determined by genes or environment is called nature

Question 3

genotype

Answer 3

the genetic code that is ‘written’ in the DNA of an individual’s cells

Question 4

phenotype

Answer 4

the physical appearance that is resulted from the inherited information

Question 5

relations between the genotype and phenotype

Answer 5

• no direct correlation
• someone inherits a recessive gene in their genotype, it may not be expressed in their phenotype
• u cannot determine the genotype by purely looking at the phenotype

Question 6

the genetic basis of behaviour

Answer 6

• Each individual possess a unique combination of genetic instructions
  ○ Hence we differ in terms of personality, intelligence, abilities etc
• The term Heritability refers to the amount of variability is a trait within a population that can be attributed to genetic differences between individuals within the population
  ○ The more the trait is influenced by genetic factors, the greater the heritability.

Eg. That the intelligence is experimented to be 60-80% affected by genes
- Seen in twins

Question 7

influence of neurochemistry

Answer 7

roles of neurotransmitters and hormones

Question 8

neurotransmitters

Answer 8

when a nerve impulse reaches the end of one neurone this is when neurotransmitters are released.

travels from one neuron, across a synapse, to another

the different types of neurotransmitters
- excitatory or inhibitory
- dopamine= excitatory (motivation)
- serotonin = inhibitory (maintenance of stable mood)

Question 9

hormones

Answer 9

• released from the endocrine glands into the bloodstream to target cells
• they influence them by stimulating receptors on the surface or inside the cell
• causing a physiological reaction

Question 10

(evolution and behaviour) Charles Darwin

Answer 10

he argues that over time, organisms become adapted to their environment through biological evolution
- the characteristics of a population changes over time

Question 11

(evolution and behaviour) natural selection

Answer 11

individuals within a species, differ from each other in terms of their physical characteristics
- survival of the fittest
- advantageous behaviour past onto offspring

Question 12

positive evaluations of the biological approach

Answer 12

1. practical application in the development of drugs
   - increased understanding of the biological processes which cause mental health diseases
   - leading to the development of psychoactive drugs ( schizophrenia and depression)
   - these target specific candidate genes to directly treat the disorder may alter neurotransmitter levels to help alleviate symptoms e.g. dopamine antagonists, such as Chlorpromazine, reduce dopamine action and so normalise neurotransmission in the hypothalamus and ventral striatum in the brains of schizophrenia sufferers
   - the require minimal effort, non- invasive and not time consuming
   - unlike CBT
2. scientific
   - use of EEG PET and fMRI scans
   - the objectively and systematically measure the biological or neural basis of behaviour
   - drugs are also developed from this basis
   - This increases the scientific credibility of Psychology, through the strict control of extraneous and confounding variables
3. supporting evidence
   - Phineas gage
   ○ Had his damaged his left frontal lobe
   ○ Behaviour very inappropriate and had a very different personality
   ○ Lacked social inhibition
   ○ Lacked a level of self control
   ○ “No longer gage”
   ○ Evidence that frontal lobe is responsible for personality and decision making.
   - Brain scanning research
   ○ Tulving et al 1994 (Pet scans)
   § Episodic memories (Personal, autobiographical and memories) and Semantic Memories (fact-based memories with no personal reference) are stored and activates in different parts of the brain.
   § Episodic in the right prefrontal cortex
   § And semantic memories on the left prefrontal context
   - Genetics and OCD
   ○ Twin study by Nestadt et al. 2010
   ○ Review in OCD and the role of genetics
   § In all the twin studies up to date, the concordance rates in monozygotic twins (same gender) were higher than dizygotic (mixed gender)
   § So should be able to conclude that the appearance of OCD is more likes to appear in both the monozygotic twins in contrast to the dizygotic twins and monozygotic twins are more genetically similar.
   § MZ has a 68% concordance rate and 31% has a concordance rate for OCD
   § Therefore gives evidence for the biological evidence for the genitic influence in behaviour.

Question 13

negative evaluations of the biological approach

Answer 13

1. Biological Determinism
   - The biological approach suggests that all behaviour is caused by internal biological forces over which we have no control i.e. the influence of genes, hormones, neurochemistry etc
   - serious implications for the judicial system and the economy
   The current judicial system expects individuals to take moral responsibility for their actions, and so such actions cannot be entirely blamed on genetic factors. However, if, for example, a criminal gene or a schizophrenia gene was discovered, this could lead to ‘diminished responsibility’ of these individuals, as well as shorter prison sentence
   * The economical impact would be that if such information about genes coding for mental health disorders or criminality were made public, then such individuals may be denied health insurance and jobs on this basis. Therefore, such biological determinism has potentially severe real-life consequences.*
2. twin studies cannot differentiate between the effects of nature and nurture
   - MZ twins usually show higher concordance rates for mental disorders and psychological characteristics compared to DZ twins.
   - F explained by how MZ twins share 100% of genes with each other, compared to only 50% for DZ twins.
   - assumption that the only differences these twins have are genetic.
   - overlooks the environmental factor of upbringing

• **MZ twins are more likely to grow up in the same household, be exposed to similar experiences and be raised using parenting styles.
• This may explain the differences in concordance rates between MZ and DZ twins, as opposed to only genetic differences.
• This may also explain why MZ twins often have higher concordance rates than ordinary siblings, despite both sharing 50% of genes.
  Therefore, this suggests that behaviour cannot and should not be explained in purely genetic terms (as suggested by the biological approach), without accounting for social contexts, through adopting an interactionist approach**