The brain Flashcards
What is the central nervous system made up of?
Brain and spinal cord
What does the left hemisphere of the brain control?
- Right side of body
- speech, language
- Analysis and calculations
- Time and sequences
- Recognition of words, letters, numbers
What does the right hemisphere of the brain control?
- Left side of body
- Creativity
- Spatial ability
- Context
- Recognition of faces, places. objects
function of frontal lobe
- processing sensory input into visual memories
- impulsivity
- emotion association
function of parietal lobe
- language processing
function of occipital lobe
- visual processing centre
function of temporal lobe
- memory making
- motivation
- attention
function of cerebellum
- motor control
Function of cerebral cortex
- stores information
- problem solving
- decision making
function of corpus callosum
- connect the two hemispheres
- communication between two hemispheres
function of thalamus
- passes information from the senses
function of hypothalamus
- regulates eating and drinking
- release of sex hormones
function of amygdala
- primary role in memory
- decision making
- emotional reactions
function of hippocampus
- spatial awareness
- navigation
What are PET scans?
- Positron emission tomography
- 3D image of functional processes
- inject radioactive traces
- see where most blood is flowing
- different levels of activity are colour coded
- scanned in two conditions: active and innactive
What are CAT scans?
- computerised axial tomography
- computer processed combinations of many x-rays from different angles to produce cross section
- digital geometry used to generate 3D image of inside of object
What are fMRI scans?
- functional magnetic resonance imaging
- using same technology as MRI, use strong magnetic field and radio waves
- looks at blood flow
- oxygen rich blood differs in colour and texture
Research using brain scanning techniques
- Raine et al
- Montag et al (used fMRI scans to see effect of violent video games on brain activity
Evaluation of brain scanning
Validity- low ecological - lab - disadvantage
individual differences - high - can identify differences between individuals - advantage
Reliability - high - controlled variables - advantage
Reductionism - social interactions influencing aggression - disadvantage
Raine et al 1997: Aim
- Participants pleading guilty for NGRI will show dysfunction in areas of the brain associated with violence
Raine et al 1997 : sample
- 41 murders (39m, 2f) pleading NGRI, mean age 31.3, free of medication two weeks prior
- 41 people (39m, 2f) matched with experimental group, mean age 31.7
Raine et al 1997 : Procedure
- consented to take part
- sequence of blurred numbers which they had to focus on for 10 minutes
- injected FDG tracer
- another 32 completing CPT task
- PET scan
Raine et al 1997: Results
- lower glucose metabolism in prefrontal cortex (responsible for self control)
- lower glucose metabolism in parietal areas ( linked to underachievement)
- assymetrical glucose metabolism in amygdala
Raine et al 1997 : conclusion
- support idea that aggression and violence may have biological cause
- limbic system including hippocampus and amygdala explain why criminals may not be able to learn from consequences of their actions
Evalutation of Raine et al
Generalisability - low - small sample - not reflective of all murders - disadvantage
Validity - low - lab conditions , task - disadvantage
controls - high - medication free - high controls - advantage
scientific - high - used PET scans - reliable - advantage
