| what are tastebuds? | grouped in papillae on tongue
no. of fungiform papillae affects peoples sensitivity to all tastes
many > high sensitivity = super tasters |
| how many and what are receptors cells on a taste bud? | 50 receptor cells
behave like neurons
release neurotransmitter to excite nearby neuron |
| 4 types of primary taste | sweet
salty
sour
bitter |
| how does the brain encode taste? | 1. taste nerves
2. medulla
3. insula |
| what are the 2 functions of the tongue? | taste
touch |
| what is olfaction? | sense of smell |
| what are the olfactory receptor cells? | in nasal cavity
hundreds of types- for many different chemicals |
| what is the olfactory bulb? | processes the info |
| what is vomeronasal sensation? | in non humans
detects odourless chemicals- affects beh.
receptors at olfactory bulb |
| what is sounds? | sound waves
frequency
amplitude |
| what are sound waves? | periodic compressions, causing vibrations |
| what is frequency? | no. of compressions per time
relates to perceived pitch |
| what is amplitude? | intensity of sound waves
related to perceived loudness |
| how are sound waves detected? | 1. pinna
2. tympanic membrane (eardrum)
3. cochlea (3 fluid filled tunnels)
4. vibrations displace hair cells in cochlea
5. auditory nerve (nerve bundle) |
| where is sound processed in the brain? | 1. ear
2. cochlear nucleus
CROSS OVER
3. primary auditory cortex |
| why can we distinguish between frequencies? | basilar membrane of cochlea
primary auditory cortex |
| what is the place theory? | each area of basilar membrane refers to specific pitch
areas too tightly linked to resonate |
| what is the frequency theory? | vibrations of basilar membrane sync with sound waves
neurons can't fire quick enough |
| what is conductive deafness? | damage of bones of middle ear |
| what is nerve deafness? | damage to cochlea, hair cells, auditory nerve |
| what is the human hearing range? | 20Hz to 20kHz |
| what is an vestibular organ? | detects position & movement of the head |
| what does the vestibular organ do? | crucial for balance
3 semi-circular canals
next to inner ear
filled with jelly like substance
lined with hair cells |
| what is huntingtins disease? | motor disorders- arm jerks, facial twitches
psychological disorders- depression, anxiety
gradual brain damage
first basal ganglia
cerebellum, cerebral cortex
strong genetic influence |
| what is Parkinson's disease? | motor disease- temper, slowness
cog. disorders- difficulty imagining movements & events
gradual death of neurons
decreased dopamine activity
reduced stimulation of motor cortex |
| what causes Parkinson's disease? | genetics- 20 genes that increase risk
exposure to toxins |
| how do we move? | 1. brain
2. spine
3. skeletal muscle |
| what does the cerebral cortex do? | control of complex movements
stimulation at each spot causes specific movements |
| what is the posterior parietal cortex? | planning & initiation of movement, monitoring position of body in space |
| what do the supplementary motor cortex & prefrontal cortex do? | planning a rapid sequence of movement |
| what does the cerebellum do? | precise timing associated with movement, attention, balancing |
| what does the basal ganglia do? | spontaneous self initiated actions |
| what do skeletal muscles do? | control movement of body in relation to environment
long cylindrical with stripe |
| what is the neuromuscular junction? | synapse of muscle fibre & motor neuron axon
each axon fibre is innervated by 1 motor neuron axon |
