The Brain Structure

• Thalmus


  passes on information from senses
• Cortex


  stores information and is involved in problem solving and decision making
• Striatum


  Important role in controlling movement and in motivation
• Hippocampus


  involved in passing short term memories into long term memory
• Venticles


  Production of cerebrospinal fluid, which helps to cushion the brain from blows and can provide nutrients
• Amygdala

  emotions and agression.

  Right links to negative emotions like fear and sadness

  Left links to a reward system and both positive and negative
• Ferret


  stores memory/ learning of practical skills
• corpus callosum

  bridge between the 2 hemispheres and transmits messages between 2 halves
• Medial temporal lobe

  encodes and transfers new explicit memories to long-term memory.

  Includes hippocampus
• prefrontal cortex


  involved with aggression

  Involves various parts incl. orbitofrontal cortex, lateral prefrontal cortex, lateral prefrontal cortex and ventromedial cortex.
• Prefrontal cortex role in emotions

  implicated depression.

  Depression links to the orbitofrontal, ventromedial, lateral prefrontal cortex.

  Lower the activity in prefrontal, means more likely there will be depression.

  Lots of connections with parts of brain relating to dopamine, serotonin, and norepinephrine which relate to emotions.

  left hemisphere = positive emotions

  right hemisphere = negative
• orbitofrontal cortex role in emotions

  linked to our accepting delayed gratification and deferring rewards
• ventromedial cortex role in emotions


  linked with experience of emotions and lateral prefrontal cortex involved in making choices in behaviour letting us see options
• prefrontal cortex role in aggression

  -Bechara and Van der Linden (2005) reviewed studies that looked at prefrontal cortex and confirmed the cortex regulates behaviour.

  - Bechara and van der linden link decision making with the ventromedial cortex

  - damage to the prefrontal cortex means someone might focus on the present and not be able to plan long term, would mean wanting immediate rewards too

  - has links to amygdala that are inhibitory and damage can mean not inhibiting such messages.
• Limbic system

  Emotions and memories.

  Includes the hippocampus, hypothalamus and amygdala

  has a role in self preservation

  structures in the limbic system control our temperature

  Linked to out autonomic system, which responds 'automatically' to danger rather than planned way.
• Hypothalamus


  regulating eating and drinking and motivated behaviours

  puts the body back into balance, like a thermostat regulating temperature.

  Regulates autonomic part of nervous system, meaning regulating body pressure pulse, breathing and arousal levels

  Detects levels of leptin, released if we overheat.
• Limbic system and aggression - studies using animals

  - Andy and Velamati (1978) carried out a study using cats. When stimulating the hypothalamus and basal ganglia of cats, the animals had aggressive seizures. Blocking catecholamine increased aggression; the opposite limited aggression.

  
  

  - Downer (1961) studied monkeys, who has one amygdala removed and the optic nerve cut. The monkey could have visual signals that went to an intact amygdala and visual signals that went to ablated amygdala. If visual input that connected to the intact amygdala, they reacted in an aggressive way.
• Strengths that brain structure relates to aggression

  - There's a lot of evidence from both animal and human studies that certain areas of the brain link to aggression such as the prefrontal cortex and limbic system.

  
  

  - Advent of scanning, such as PET and fMRI scanning which has more precision than earlier scanning techniques, more can be measured and studied
• Weaknesses of brain structure relates to aggression

  - Animal studies might have findings that cannot be generalised to humans because of differences between humans and animals. Animals don't have the same prefrontal cortex as humans

  - Scanning is said to be reliable, however, validity is in question because the scan has to take place while someone is processing is likely to be an artificial task . People don't function normally in brain scanners
• Gorka et al (2013)


  asked people to look at happy, angry or fearful faces and tested their prefrontal cortex to amygdala connectivity under the influence of alcohol. Concluded that alcohol affected the connection between amygdala and prefrontal cortex