localisation of function in brain

• Localisation of function


  The theory that different areas of the brain are responsible for specific behaviours, processes or activities
• Motor area


  • A region of the frontal lobe involved in regulating movement
• Somatosensory area


  • An area of the parietal lobe that processes sensory information such as touch
• Visual area


  • A part of the occipital lobe that receives and processes visual information
• Auditory area


  • Located in the temporal lobe and concerned with the analysis of speech-based information
• Broca's area


  • An area of the frontal lobe in the left hemisphere (in most people), responsible for speech production
• Wernicke's area

  • An area of the temporal lobe (encircling the auditory cortex) in the left hemisphere (in most people), responsible for language comprehension
• if a certain area of the brain becomes damaged through illness or injury, the function associated with that area will also be affected.
• The main part of the brain (the cerebrum) is divided into two symmetrical halves called the left and right hemisphere.
• lateralisation is when our physical and psychological functions are controlled or dominated by a particular hemisphere
• left hemisphere controls the right side of the body
• right hemisphere controls the left side of the body
• Language is linked to the left hemisphere.
• The cerebral cortex is the outer layer of both hemisphere
• The cortex of both hemispheres is subdivided into four centres - called the lobes' of the brain:

  1. the frontal lobe
  2. the parietal lobe
  3. the occipital lobe
  4. the temporal lobe
• At the back of the frontal lobe (in both hemispheres) is the motor area which controls voluntary movement in the opposite side of the body. Damage to this area of the brain may result in a loss of control over fine movements such as writing or drawing.
• At the front of both parietal lobes is the somatosensory area
• The somatosensory area is where sensory information from the skin (e.g. related to touch, heat, pressure, etc.) is represented. The amount of somatosensory area devoted to a particular body part denotes its sensitivity, for instance, receptors for our face and hands occupy over half of the somatosensory area.
• In the occipital lobe at the back of the brain is the visual area
• Each eye sends information from the right visual field to the left visual cortex and from the left visual field to the right visual cortex. This means that damage to the left hemisphere, for example, can produce blindness in part of the right visual field of both eyes.
• The temporal lobes house the auditory area, which analyses speech-based information. Damage may produce partial hearing loss.
• Damage to Broca's area causes Broca's aphasia which is characterised by speech that is slow, laborious and lacking in fluency.
• People who have Wernicke's aphasia will often produce nonsense words (neologisms) as part of the content of their speech.