Biological approach

• 5 genes

  MAOA Warrior gene (violence)

  CDH13 Cadherin 13 (violence)

  DISC1 schizophrenia

  DAOA/G72 Schizophrenia

  5HTT depression

  Gene creates predisposition for behaviour
• Assumption: behaviour shaped by evolutionary influences

  Inheriting certain genes increases likelihood of behaviours

  If trait promote survival or reproduction, it will pass onto the next generation ( natural selection)

  EEA (environment of evolutionary adaptiveness) The environment to which any species is adapted and selective pressures at the time-> explains the size of the human brain because of our complex social organisation
• Neurotransmitters and relationships

  Impact emotions. Dopamine links to pleasure seeking behaviour so the goal of finding a partner and drive to achieve this gives a natural high

  Oxytocin links to human bonding and high levels link to romantic attachment. Lack of physical contact can lower. We have a natural chemical drive to bond
• Assumption: neurotransmitters

  Neurons form basis of nervous system connecting to each other with dendrites. They communicate across dendrites with neurotransmitters (chemical messengers). Neurotransmitters released from presynaptic vesicles in a neuron and either stimulate or inhibit receptors in other neuron. Serotonin influences mood, appetite and sleep, low levels associate with depression.
• Evolutionary influences and relationships

  Men look for features in a female partner that indicate fertility ( young, hourglass figure, smooth skin etc)

  Females seek partner who can provide ( older and wealth)

  Parental investment theory: as female mammals invest more in offspring they must be choosier in a partner to find male with the most resources
• Broca’s area

  In frontal lobe-> speech production and language processing

  discovered by Paul Broca who studied 8 patients with long term problems post-mortem and saw damage in this area
• Assumption: localisation of brain function

  Frontal lobe: thinking,creativity and personality

  Parietal. sensory; touch temperature and pain

  Temporal: memory processing and processing auditory info

  Occipital: visual processing and information from eyes
• Purple: frontal lobe

  Yellow: Parietal lobe

  Orange: temporal lobe

  Blue occipital lobe

  
• Weakness nomothetic

  Doesn’t account for individual differences so is a superficial and impersonal view of behaviour

  Assumes all biological systems are the same

  Male bias in research as female hormone may interfere - men have fight or flight instinct but women show tend or befriend where they nurture young or seek social support

  Women release oxytocin when stressed
• Weakness: nature

  Ignores nurture including life experience and physiological factors like thoughts and feelings

  may ignore development of behaviour
• Weakness: reductionist

  Simplified explanations- stress only due to adrenaline ignoring feelings of distress that come with mental illness an incomplete explanation

  Cannot reach a true understanding of the behaviour
• Strength: application

  Benefits those who receive therapy and there is a lot of evidence for success

  relationships between abnormal neurotransmitter levels and criminal behaviour has implications of offering pharmacological treatment - safer society

  67% recovery from cingulotomy to treat ocd
• Strength: determinist

  easier to develop treatment as we know what determines behaviour.

  EG predict effect of neurotransmitters on behaviour (high dopamine link to schizophrenia)

  EG OCD increases activity in certain areas so treat with cingulotomy
• Strength: scientific

  Biological explanations have clear variable that are measured and examined

  Raine et al used PET scans to compare brain differences in murderers and non murderers

  Psychosurgery functionally removes parts of brain

  As it is scientific people are more likely to believe principles