Lateralisation and Split Brain

• Lateralisation

  Division of functions between two hempheres
• What are clear structures in the brain?

  Gyri, sulci and fissures
• Left side is specialised for language
• Corpus Callosum

  fibre bundle that connects areas within the two hemispheres
• What other areas exchange info?

  Anterior commissure, hippocampal commissures and other small commissures.
• Why do young children have difficulty comparing or integrating actions between right and left hands?

  As corpus callosum matures between 3 to 5 years.
• Human vision:

  The left half of each retina connects to the left hemisphere, i.e. sees the right visual field

  The right half of each retina connects to the right hemisphere, i.e. sees the left visual field

  Half of the axons from each eye cross to the opposite side of the brain at the optic chiasm
• Two systems that are lateralised?

  Somatosensory and motor
• What cognitive functions are examples of lateralisation as suggested by neuropsychological disorders?

  Language, handedness and attention
• Damage to what area causes Broca's aphasia?

  Broca's area = BA 44 & 45
• What area of the brain if damaged can cause Wernicke's' aphasia?

  Wernicke's area = Part of BA 39 & 40
• Most left-handers have a left hemisphere dominance for speech
• Spatial perception: When given equal choices, most right-handers prefer to turn left
• Apart from Wernicke's area what area is critical for speech comprehension?

  Planum Temporale
• Different types of attention

  • Reflexive
  • Voluntary
  • Spatial
  • Temporal
• What is reflexive attention?

  Exogenous / bottom up attention
• What is voluntary attention?

  Endogenous / top-down attention
• What can right hemisphere damage lead to?

  Spatial neglect
• Spatial Neglect

  tendency to ignore the left side of the body and its surroundings or the left side of objects
• What determines the type of neglect?

  Exact location of damage
• What causes neglect to everything to the left of one's own body?

  Inferior right parietal cortex damage
• What location causes neglect to left side of objects?

  Superior temporal cortex damage
• What test is used to assess neuropsychology of attention?

  Cancellation test

  
• Spatial neglect is also known as?

  Disorder of attention
• Enlarged ventricle shows that what has been removed?

  Corpus Callosum

  
• What did Gazzaniga 2000 find relating to split-brain research?

  The left hemisphere acts as an interpreter

  Tendency to invent and defend explanations for actions when true causes are unconscious
• What are 2 key features of human language?

  Complex form of communication

  High Productivity
• What is meant by productivity when describing the human language?

  Ability to improvise new signals to represent new ideas
• How does chimpanzee language differ from human language?

  Little new, original combinations of symbols

  Lacks productivity

  Used to request not describe
• Studies of non-human language abilities allow for insight into?

  How to teach language to those who do not easily understand like those with brain damage and autism

  Precursor to human language
• Two points outlining how language has evolved?

  Anatomical / functional predisposition

  It may have evolved from communication through gestures
• Describe anatomical functional predisposition

  Strong connection between auditory and prefrontal cortex

  Phonological loop: Ability to hear something and remember it
• What language-based symptoms do people with Williams syndrome suffer from?

  Impaired intelligence but normal language skills
• Who describes language as an acquisition device?

  Chomsky and Pinker
• Language acquisition device

  Built-in mechanism

  Ease at which children develop language
• What gland was used by Descartes to show that the mind and brain interact simultaneously?

  Pineal gland
• Name experimental paradigms of conciousness

  Stroop test, Masking, Binocular rivalry, Phi phenomenon
• Stroop test outlined?

  Much of brain activity is unconscious and can influence behaviour

  The brain attends to some things even if you are not conscious of the stimulus.
• Masking shows how unconscious stimuli can influence behaviour
• Binocular rivalry

  Slow and gradual shifts of the eye sweeping from one side to another

  Stimulus seen by each eye evokes a brain response measured by fMRI or EEG