localisation of function Flashcards
what is localisation of function
o Localisation of function, or cortical specialisation, is the idea that different parts of the brain perform different tasks and are involved with different parts of the body
o Therefore, if a certain area of the brain is damaged through illness or injury, the function associated with that area will also be affected
what is hemispheric lateralisation
- The brain is divided into two symmetrical halves called the left and right hemispheres.
- Some of our physical and psychological functions are controlled by a particular hemisphere- this is called lateralisation.
- Activity on the right-hand side of the body is controlled by the left-hand side of the brain and vice versa e.g. language is linked to the left hemisphere
what is the cerebral cortex
- The outer layer of both hemispheres is the cerebral cortex.
- About 3mm thick, the cortex appears grey due to the appearance of cell bodies and dendrites; it is often referred to as ‘grey matter.
- The cortex is divided into four lobes: the frontal lobe, the parietal lobe, the occipital lobe and the temporal lobe
outline the motor area
® At the back of the frontal lobe is the motor area
® 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
outline somatosensory area
® At the front of both parietal lobes is the somatosensory area
® Sensory information from the skin e.g. touch, heat, pressure, is represented
outline visual area
® In the occipital lobe at the back of the brain is the visual area
® Responsible for sight
® Damage to the left hemisphere can produce blindness in part of the right visual field of both eyes
outline auditory area
® Located in the temporal lobes
® Analyses speech-based information
® Damage may produce partial hearing loss and damage to a specific area (Wernicke’s area) may affect the ability to comprehend language
outline broca’s area
- An area of the frontal lobe of the brain in the left hemisphere responsible for speech production.
- Identified by Paul Broca- a surgeon- in the 1880s.
- Damage to Broca’s area causes Broca’s aphasia which is characterised by speech that is slow, laborious and lacking in fluency.
- Does not affect understanding
- Difficulty with prepositions and junctions
outline wernicke’s area
- An area of the temporal lobe in the left hemisphere, responsible for language comprehension.
- Wernicke’s aphasia occurs due to damage to this area and results in fluent, but meaningless language - have no problem producing language, but understanding it
- People with Wernicke’s aphasia will often produce nonsense words (neologisms) as part of the content of their speech.