sensory + motor Flashcards
2 types of muscle receptor
muscle spindle and golgi tendon organ
golgi tendon organ sends ______ to _____ and consists of ____ and _____
muscle tension info / CNS / collagen fibers / 1b afferentnhow to activelky
how to actively contract and passively stretch muscle?
when muscle streetch, 1a & 1b afferent has to increase AP firing rate
when extrafusal muscle fiber contract, 1a > & 1b <
how is primary motor cortex organized?
musculature requireing fine motor control (i.e palm) copu greater space in motor cortext than one w/ les sprecise (stomach)
goal of brain machine interfaces and how do they do it?
restore motor function for patient w. spinal cord damage w/ implanted microelectrodes & use population coding algorithm to control prosthetic devices
without cerebellum, you couldn’t….
- evaluates differences btw intended action & actual one while movmnt is progressing
bcs cerebellum receives input frm cerebral cortext, brain steam & spinal cord
+ sends it back to them. a loop.
which inputs prject FROM cerebellum?
cerebellar cortext oi dee cerebellar nuclei -> motor cortex via thalamus
direct sensory inputs of the cerebelum include ___ ___, ____ ____ and other mechanoreceptor
other brain stem inputs include ____ olive & locus ____
vestibular nuclei / nmuscle spindle
inferior / coerulus
mossy fiber vs climbing fiber
mossy: synapse from granule cells, forming parallel fibers to purkinje cells
synapse directly on purkinje cells
symptoms of parkinson’s disease and how to treat it
tremor at rest, rigti gaint, minimal facial expression, slow movement
oral L-dopa/lero dopa, deep brian surgery of STN and GPI
describe the anatomy of a muscle spindle
extra muscle fibre
- alpha motor neuron innervates it
golgi tendon organ below
inside, intrafusal fiber and 1b afferent
gamma motor neuron innversaves intrafusal fibre
compare the effect when a-motor neuron is activates vs when both alpha & gamma motor neuron coactivated?
alpha only: extrafusal musle contract
no AP created
slack muscle spindle & cant signal length change
alpha & gamma motor neuron: tension is maintained and can signal length change
if you put a load muscle, how to prevent overstretching?
- load added to muscle
- muscle spindle streches as arm extends downward
- 1a afferent fires AP
- synpase directly w/ alpha motor neuron to extrafusal muscle fibre of same muscle
- reflec contraction initated (arm extends upward_)
lateral vs ventral corticospinal tract?
lateral; cross in medulla
involved in fine mvment & distal/extremity muscle
ventral: cross in spinal cord
involved in gross mvment & axial/ trunk muscle
explain what is reciprocal innervation in the pattelar tendeon reflex?
QUAD contracts: muscle spindle stretche
-> 1a afferent fire AP
synapse directly to alpha motor neuron and quad femoris
quad contracts + lef springs forward
HAMSTRING relaxes: collateral (1a afferent also synapses to inhibitoryt interneuron in spinal cord
, which inhibits alpha motor neuron to hamstring muscle
-> it relaxes and lefg stend forward
compare cerebellum vs basal ganglia: function and loop?
function: evaluates differences btw intended actions and actual ones irl. for motor adaptioan & learning VS planning mvment
loop: receives input from cerebal cortext -> brain stem-> spinal cord project it back VS …cortext then project it back via thalamus
output from the cerebellum?
cerebrallar cortex -> deep cerebrallar nuclei -> motor contex
input of basal ganglia?
hint: all cortical areas project to ____, excluding ____/ _____
input: caudate & putamen
all cortical areas project to them excluding primary visual/ auditoyr cortext
caudate & ___ send output through ___ ___ & _____ ___ ___ ___
further to ___ ____-> ____ & back to _____ cortext
=> output of basal ganglia
putamen / globus pallidus & substantia nigra par compact
subthalamic nucleus /thalamus / cerebrel cortex
compare the indirect vs direct pathway in basal ganglia
(+) motor cortext excites putamen
(-): indirect STOPS mvment: …inhibits G.P external -> blocked GP e cant inhibit subthalamic nucleus -> activat4es GP internal -> inhibits thalamus -> cant activate motor cortex
direct PROMOTES mvmnt: inhibits GP internal -> blocked GP internal cant inhibit the thalamus _. acticates motor conrtex
distinct 2 classes of sensory receptors
complete neural receptor & special sense receptor
(+): myelinated axon and cell bodoy
(-) specialized nerve ending VS specialized cell receptor
for olfaction & somatory senses VS vision, hearing, taste & balance
compare the way complete neural receptor vs special sense receptor transduce a stimulus
all similiar: stimuli acts on receptor
alters its membrane
local flow within (recep potential -> graded potential)
complete neural: changes in AP frequency and opens more channels -> AP propagation to CNS
special senses: releases neurotransmitter -> changes in post-synaptic membrane potential + aP frequency
->AP propagation to CNS
how can we distinguish odour?
every taste activates different receptor to a diff degree -> interprets by CNS
small receptive field - ____ (flutter + stroking) & ____ (steady ____ & ___)
large- ruffini’s ending (___ ___) and ____ (vibration) bcs they are ______ , need to _________ hence larger receptive field
meissner’s corpuscle / merkel’s disk / pressure & texture
skin stretch pacinian’s corpuscle / located far deeper into skin
more ____ musculature (i.e ____) occupy greater spaces in the somatosenory cortex
sensitive
state 2 differences btw beta, delta and C nociceptors
1: Beta has large, myelinated fiber / delta has small myelinated / C has small unmyelinated
2: beta responds to touch /
intense mechanical or mechanothermal stimuli /
C for heat cold slow pain
what is going on when you accidentally burn yourself starting from the spinal cord?
pain reflex steps in!
starting from the spinal cord, primary neuron travels to medulla
since it’s nociceptor, cross in the spinal cord
secondary neuron travels to the thalamus
tertiary neuron travels to the somatosensory cortex
describe how light transduction occurs in photoreceptors without light and light stimulus
In darkness, Na & Ca++ channels open -> rods & cones depol
=> release neurotransmitter
=> inhibit the activation of bipolar cells
In light stimulus, Na & Ca++ channels closed -> rods & cones hyperpol
=> release less OR stop neurotransmitter
=> activated bipolar cells send signals from ganglion -» optic nerve
RODS vs CONES
highly sensitive to light vs less sensitive
vision @ low light lvl vs color vision( 3 types to repsond to RBG wavelength)
how forvea gets a higher acuity
surrounding cells are pushed aside (curved) alowing light to strike photoreceptor directly
list 5 types of eye movements; define them if necessary
- saccades: rapid, jerky eye mvment that follow line of sight
- smooth pursuits: keep img on fovea
- vestibulo-occular reflex: stabilize the eye during head mvment
- vergence = follow obj appraoching / moving away
- optokinetic reflex
describe how sound waves travel to the inner ear, or sound transduction
- sound waves strike tympanic membrane
- transfer its energy into ossicle
- via stapes, vibration of oval window creates fluid wave within cochlea duct
describe how low / high frequency is coded in the ear
fluid waves travel along basilar membrane
low frequency: wide, thin
high: short and thick
light first passes through axosn of ___ ____ -> ____ cells -> ____ cells -> photoreceptor
only cells that generate AP is ___, graded potential ___ cells
optic nerve / gangion / bipolar /
ganglion / bipolar cells
4 somatic senses:
- touch
- proprioception = how the body is located in space
- temp
- nociception
when a ____, longer stimuli and receptor potential is ___ & longer, AP frequency is ___ & longer
stronger / larger / higher
describe where the different 6 senses terminate in the CNS
vision -> visual…
hearing -> auditory
taste -> gustatory….
touch -> somatosensory cortex
balance all synpase to the thalamus and their respective cortex
balance is vestibular apparatus
only for smell, nose -> olfactory bulb -> olfactory cortex
describe the pathway for sensory neurons
spinal cord to medula: primary neuron
medulla to thalamus: secondary neuron
thalamus -> somatosensory cortex: tertiary neuron
___ touch, propriocetion & ____ cross in the _____ while ____ touch, ___ & nociceptor cross in _____
fine / vibration / medulla / coarse / temp / spinal cord
3 types of hearing loss
conductive: sound cant ____ in _____ & _____ ear
sensorineural: damage to the structure of _____ ear
central: damage to the ____ ______
transmit / outer / middle
inner
auditory pathways
