biological psychology

• Central nervous system


  Consists of the brain and spinal cord
• Nerves


  Connecting the nervous system
• Neuron


  Role is to pass messages between neurons using neurotransmitters to enable behaviour
• Electrical impulses


  Travel down axon to trigger release of neurotransmitters
• Neurotransmitters


  Carry messages from 1 neurone to another
• Neurotransmitters


  • Dopamine (the pleasure feeling)
  • Noradrenaline (prepares fight or flight)
  • Serotonin (happiness)
• Synaptic transmission


  How information goes over a 'synaptic gap' from 1 neuron to another
• Synaptic reuptake


  When the neurotransmitter is absorbed back into presynaptic neuron
• SSRI's


  Blocking drugs that fill the receptor so the natural neurotransmitter cannot pass message on - prescribed for depression - they block the reuptake of serotonin- leaves more serotonin at synapse to be taken by receptor
• Recreational drugs


  Alter brain activity and functioning which can change an individual's mood and perception
• Reward pathway


  What the brain contains and releases a rewarding feeling
• Dopamine release


  Occurs after pleasurable experience
• Cerebral cortex


  Left hemisphere associated with verbal processing, right hemisphere associated with non verbal processing
• Thalamus


  Sorts and relays incoming information to different parts of the forebrain
• Occipital damage


  May cause cross-eyeing, makes sense of visual info
• Corpus callosum


  Responsible for transmitting neural messages between both right and left hemispheres
• Limbic system


  A group of structures in the brain associated with emotions, made up of the amygdala and the hippocampus
• Amygdala


  Controls the way we react to certain stimuli and see potential danger
• Temporal lobe


  Leads to failure to store new information and problems in understanding what others are saying to us
• Parietal lobe


  Involved with attention and motor control and receiving pain, touch and temperature
• Frontal lobe


  In control of voluntary muscles, intelligence, personality and carry out planning
• Neurotransmitters affecting aggression


  Low serotonin may make people less able to resist being aggressive, high levels of dopamine cause high levels of aggression
• Studies on aggression


  • Downer 1961 - used monkeys and showed amygdala was involved in aggression
• Amygdala


  Seen as an area of aggression, responsible for our instinct emotional response
• Prefrontal cortex


  Deals with complex planning, cognitive behaviour and decision making, with low levels of serotonin the brain will find it difficult to manage decision making
• Hippocampus


  Important role in taking short term memories and converting them to long term memories, inability to do this then will spark aggression
• Hypothalamus


  Part of the midbrain which maintains stability of human body, maintains hormones e.g. sexual function, testosterone causes aggression due to serotonin levels
• Natural selection


  Made by Charles Darwin, believes only the fittest will survive and will reproduce 'survival of fittest'
• Evolution


  We collect 50% of genes from mum and 50% from dad, the theory suggests that we have evolved through time and have survived the fittest
• Aggression


  Can be evolved through genes from mum or dad being seen as stronger, humans who were aggressive and seen as stronger in social group are likely to survive limited resources
• Freud's psychodynamic explanation


  Conscious mind - what we are aware of, preconscious mind - holds thoughts that are ready to be known but not conscious, unconscious mind - active thoughts that are finding meaning of expression
• Id


  What we are born with, unconscious as demands are not satisfied
• Ego


  Works on reality principles trying to obtain what Id wants
• Superego


  Made up of conscience knowing right from wrong
• Catharsis


  An emotional release linked to a need to relieve unconscious conflict
• Defence mechanism


  Protects the ego from temporary threat or trauma and cope with issues
• Testosterone


  An androgen which develops and maintains male characteristics, so is more dominant in males, appears to be related to aggressive behaviour
• Studies on hormones and aggression

  • Dabbs et al (1987) - measured testosterone in the saliva of 89 male prisoners involved in violent crime, 10/11 of prisoners who committed crime had high levels of testosterone

  Barzman et al - looked at 17 boys in psychiatric hospital aged 7-9, found aggression correlated with amount of testosterone

  Chang et al (2011) - carried out study looking at fish, found aggression, boldness and exploration all correlated with amount of testosterone and cortisol
• Raine et al (1997)


  Investigated brain patterns in murderers compared to non-murderers using PET scans, also wanted to see differences in prefrontal cortex of murderers pleading not guilty compared to non-murderers
• Li et al (2013)


  Investigated the relationship between chronic heroin use and effect on brain, also to see if heroin is associated with craving-related changes in the posterior cingulate cortex