localisation of function

• functions such as movement, speech and memory are performed in distinct regions of the brain (localised). The opposite view is the brain acts holistically to perform functions,
• functionally specialised areas of the brain- motor, somatosensory, visual and auditory cortices are on both sides of the brain. Broca and Wernicke's area are only in the on left hemisphere (hemispherically lateralised).
• hemispheric lateralisation- each hemisphere of the brain (right/left) is specialised to perform different functions. (language centers are in the left hemisphere, visuospatial tasks are best performed by the right.
• left side- language centers, right side- visou-spatial processing
• visual, motor and somatosensory are contralateral. meaning both the sides of the brain, right and left controls the opposite side of the body, including both motor and sensory pathways and vision of the contralateral field,
• occipital lobe/visual cortex, the brains visual processing center, each hemispheres occipital lobe receives information from the contralateral visual field.
• occipital lobe- found at the back of the brain
• motor and somatosensory cortex- motor cortex is at the back of the frontal lobe and the somatosensory cortex is at the front of the parietal. they are divided by a fold called the central sulcus and are contralateral
• motor cortex- area of the brain responsible for voluntary motor movements (eg deciding to move arm). contralateral
• somatosensory cortex- area of the brain responsible for for receiving sense impressions from around the body, contralateral
• auditory cortex- receives and processes sound information from ears, located in both hemispheres, located at the top of temporal lobe
• damage to auditory cortex- can lead to deafness,
• broca's area- located in left hemisphere only, broca's area is responsible for speech production,
• wernicke's area- left hemisphere- located in top temporal lobe, wernicke's is responsible for speech comprehension, discovered after case studies of individual who could produce fluent sounding speech that made little sense.
• The Broca’s area is the main area where speech is produced. It is located in the frontal lobe of the left hemisphere.
• Damage to the Broca’s area causes Broca’s aphasia (also called expressive aphasia), a condition characterised by slow speech, lack of fluency, and an inability to find the right words. Despite difficulties producing speech, people with Broca’s aphasia often have normal language comprehension – i.e. they understand what others are saying.
• Another important (but separate) area for language is Wernicke’s area. The Wernicke’s area is primarily responsible for language comprehension (both written and spoken). It is located in the temporal lobe.
• Damage to the Wernicke’s area causes Wernicke’s aphasia (also called receptive aphasia). Patients with Wernicke’s aphasia typically have no problems producing speech – they speak in a fluent and effortless way – but the content of what they say often lacks meaning.
• left side of the body is controlled by the right hemisphere (vice versa)
• the outer layer of both the right and left hemispheres is called the cerebral cortex which separates us from animals and ours is much more developed
• the centres of the cerebral cortex- frontal lobe, parietal lobe, temporal lobe and occipital lobe
• frontal lobe- motor cortex- controls voluntary movements in the opposite sides of the body, eg your left motor cortex controls right side of the bodys voluntary movements- damage may result in loss of control. Also home to brocas area- damage may result in speech production loss eg Tan could only say Tan
• parietal lobes- somatosensory cortex location- information from the senses- skin, related to touch or heat or pressure is represented, the amount of somatosensory area devoted to a particular body part denotes its sensitivity,
• occipital lobe- location of the visual cortex, each eye sends info from right visual field to left visual cortex and vice versa,
• temporal lobe- auditory cortex- analyses speech based information, damage may impair ability to comprehend speech- Wernicke's area