brain Flashcards
why is the brain remarkable?
- bigger than average for our size of body
how heavy is an average human brain?
- 1.5kg
is there a relationship between brain size and intelligence?
no- cows have the same size brain as a chimp
what happens in most animals when brains get bigger? what animal does this not include
neurons get bigger but in primates neuron size remains the same= more neurons can fit in
how many neurons are in the brain?
- 86 billion ; 80% in cerebellum
- each neuron connected directly w/ around 10,000 others
how much of cardiac output is directed to the brain?
- 15-20 %
- cells consume large amounts of glucose
what is the advantage of having a big brain ?
- allows for more complex motor behaviours
what makes up the brainstem?
- medulla
- pons
- cerebellum
what does medulla control?
- cardiac function, respiration and reflexes
what do pons contain and describe its role
- contains nuclei that relay signals from forebrain to cerebellum
what is cerebellum responsible for?
balance and helps with coordination
what is cerebrum involved in?
- volitional movements
what makes up the midbrain?
- tectum
- substance nigra
what is tectum involving?
- movement in response to external stimuli
- rapid orientation of head and neck
what does substancia nigra produce?
- dopamine
what may result if substancia nigra is damaged?
- parkinsons
what is the spinal cord responsible for?
- automatic movements
where are the two parts of dienchaphelon found and what are they?
- found at bottom of forebrain
- thalamus
- hypothalamus
what does the thalamus do?
- takes info from periphery and passes it to cortex
what do hypothalamus regulate?
- hormones
what is the series of interconnected nuclei?
- basal ganglia
- found in cerebrum
what is the cerebral cortex?
- found outside of the cerebrum
- highly folded containing 6 layers of cells
what is the cerebral cortex important for ? (7)
- movement
- attention
- perception
- consciousness
- thought
- language
- memory
what are the folds in the brain called?
- gyri
what are the grooves in the brain called?
- sulci
what is the cortical control of movement?
- consists of 4 lobes; frontal, parietal, temporal and occipital
what is found in the frontal lobe ?
- primary motor cortex, premotor cortex and prefrontal cortex
what does the primary motor cortex code for ?
basic parameters of movement e.g. force, speed
how long before movement does primary motor cortex fire?
5 to 100ms before
what does pre- motor cortex code for ? give examples
- more complex aspects of movement
- planning movement, spatial guidance
what does supplementary motor area code for ? give example
- other complex movements
- coordination sequence of actions
what is found in parietal lobe?
- somatosensory cortex
what does sensory cortex code for?
- touch, vibration, heat, pain and pressure
what is the ability to recognise position of joint?
- joint position sense
what is the ability to recognise joint movement?
- kinaesthesia
what is the ability to appreciate and recognise force generated?
- sensation of resistance
what is found in temporal lobe?
- auditory cortex
what is found in occipital lobe?
- visual cortex
