exam 1 Flashcards
Ventromedial Pathways
reactive + balance tracts
Tectospinal tract
ventromedial tract responsible for coordinating audiovisual information
reticulospinal tract
ventromedial pathway responsible for voluntary and involuntary movements, muscle tone, and spinal reflexes
vestibulospinal tract
ventromedial pathway responsible for facilitating VOR and limb extensor muscles in response to otolith organs
Antero lateral pathway
voluntary movements
Rubrospinal tract
antero lateral pathway responsible for gross motor movements + motor coordination
corticospinal tract
anterolateral pathway important for fine motor movements
spinocerebellar tract
sensory tract responsible for relaying non conscious, proprioceptive information
spinothalamic tract
sensory tract responsible for relaying information about touch, pain, and temperature
Dorsal column medial lemniscus tract
sensory tract responsible for relaying conscious, refined touch, proprioception, and vibration
alpha motor neurons
innervate extrafusal muscle fibers to cause muscular contraction
encapsulated endings
primarily mechanoreceptors that inform about object movement and frictions
free endings
primarily act as nociceptors
proprioceptors
low grade mechanoreceptors that inform the CNS about movement and position by detecting stretch
muscle spindles
detect muscle stretch
golgi tendon organs
detect applied force
joint receptors (type 1-4)
act as limit detectors
gamma motor neurons
innervate intrafusal muscle fiber to cause contraction of the spindle to allow it to stay taut
type Ia afferents
faster, sensitive to speed and length of stretch
Type II afferents
slower, sensitive to length of stretch
Type 1 receptor
ruffini-like receptor (static joint position, joint movement, direction, and speed)
type 2 receptor
paciniform receptor (joint movement and movement velocity)
type 4 receptor
free nerve endings
photoreceptors
responsive to light
mechanoreceptors
responsive to mechanical energy (touch, vestibular receptors)
chemoreceptors
responsive to certain chemical substances (taste and smell)
thermoreceptors
responsive to thermal energy (hot/cold)
exteroreceptors
sense information from outside the body
interoreceptors
sense information from inside the body
proprioceptors
sense information from the body itself (movement)
intensity coding
receptors can detect and code strength or magnitude of stimulus
graded response
the greater the stimulus, the greater the response
spatial summation
the larger the number of receptors that are stimulated, the stronger the perceived stimulus
temporal summation
a strong stimulus causes receptors to fire at a higher frequency than a weak stimulus
adequate stimulus
most receptors are built to respond only to one kind of stimulus energy
modality
when a specific receptor is stimulated to cause a consciously perceived sensation, you get the same modality of sensory experienced
adaptation
response slows with sustained stimulation
slow adapting stimulus
info about the size and shape
fast adapting stimulus
info about direction of movement
receptive field
the region of a sensory surface that, when stimulated, modulates the activity of a neuron
Weber’s Law
the minimum amount that the strength or intensity of a stimuli must be to produce a perceived difference in the sensory experience (JND=K(I))
two point discrimination
our ability to discern points as being distinct (especially for sensation of touch)
vestibular system functions
perception of self motion, perception of head position, spacial orientation
x + y axis
anterior and posterior canals
z axis
horizontal canal
endolymph
fluid within semicircular canal
capula
hair cells within the canals
head rotation
deformation of capula in opposing directions (head turns right, increase in firing on left side, decrease in firing on left side)
otolith organs
utricle and saccule
utricle
responsible for detecting linear accelerations and horizontal head-tilt
saccule
responsible for detecting linear accelerations and vertical head-tilt
structure of otolith organs
contain heair cells within jelly like substance with otoconia on top
acceleration forwards
firing rate increases as otoconia are thrusted backwards
acceleration backwards
firing rate decreases as otoconia are thrusted forwards
tilting head back
increases firing rate as otoconia slide backwards
tilting head forwards
firing rate decreases as otoconia slide forward
VOR
coordinate eye movements that maintain a stable image on the retina
Dorsal horn
incoming afferent sensory informatino
ventral horn
outgoing efferent motor information
frontal lobe
executive functions, cognition, decision making for. motor control
temporal lobe
hearing, olfaction, object recofnition
parietal lobe
sensory information, vestibular information, and the integration of sensory and motor information
occipital lobe
visual information
M1
primary motor cortex, movement execution
S1
primary somatosensory cortex, processing sensory information
SMA
supplementary motor area, learning movement sequences, bimanual motor activities
FEF
frontal eye fields, eye movements
brocas area
speech production
basal ganglia
control of voluntary movement, initiation and completion, activating and retrieving movement plans, scaling movement parameters
cerebellum
posture and balance, motor learning, motor coordination
cerebrocerebellum
premotor cortex, motor planning
spinocerebellum
motor cortex and brainstem, motor execution
vestibulocerebellum
motorneurons in spinal cord and brainstem
EEG
direct measure of the brain that records electrical patterns
MEG
direct measure of the brain that records magnetic fields produced by electrical activity of the brain
PET
indirect measure of the brain that tracks radioactive markers within the brain
fMRI
indirect measure of the brain that aligns atomic particles and measures the interaction with radiowaves
sensory neurons
detect changes in the environment (stimuli)
motor neurons
send signals to target tissues in order to elicit a response to a particular stimulus
interneurons
neither sensory or motor, serve an integrative function
dynamic polarization
information flows from the dendrites to the axon terminals and information will not back-propogate
connectional specificity
no cytoplasmic connection between neurons, they make precise connections
action potential
influx and efflux of sodium and potassium ions across the membrane
Electrical synapses
direct connections between neurons through gap junctions
chemical synapses
communication between synapses via the release of neurotransmitters
multiple sclerosis
damage to the myelination causing possible loss of vision, tingling, numbness, muscle weakness, poor corrdination
white matter
myelin surrounding axons
gray matter
soma and dendrites
skill
an action or task that has a specific goal
properties of a skill
goal directed, voluntary, acquired through experience/practice
discrete action
clearly specified beginning and end
serial movement
involve a series of discrete movements
continuous movement
have an arbitrary start and end
low cognitive demand
actions are automatic, with little thinking about the task required
high cognitive demand
the motor component is less significant than the cognitive element
closed environment
environment does not change while performing the skill
open
environment is changing during the performance of the skill
ability
stable trait or capacity of the individual that is a determinant of a person’s potential for the performance of a specific skill (thought to be hereditary)
individual differences
differences among people that contribute to differences in task performance (body type, cultural background, emotional makeup, developmental stage, abilities)
motor fit
achieving the same motor outcome despite different circumstances
adaptation/adaptability
the ability to change motor behavior depending on the circumstances
motor equivalence
equality of outcome of two or more movements, movement patterns, or muscle contractions that may be different in other respects
voluntary motor control
goal directed behavior that is performed deliberately and with the conscious intention to achieve the goal. performer is aware of having the choice whether or not to carry it out
involuntary behavior
behavior that is not voluntary. Performed without conscious intention, and the person is not aware of having a choice about whether it is produced or not
parkinson’s disease
loss of dopamine neurons in the substantia nigra (part of the basal ganglia) that may cause tremor, bradykinesia, freezing, shuffling gait, impaired posture/balance, muscular rigidity
huntington’s disease
hyperkinetic disorder that results in chorea (dance like movements), lack of coordination, emotional and cognitive impairements
goal directed characteristics
adaptability + persistence in response to failure
movement error
when what we plan and what we do, do not align
internal model
preprogrammed basis of movement contained in the brain, thought to live in the cerebellum
open loop control
comands are preset, we have to wait until the next movement to make a correction
closed loop control
uses feedback to continue to improve movement, making corrections along the way
disturbance
cause of movement error where inputs external to the control system affect the controlled variables
controller mistake
cause of movement error where the controller could make a change in the control variable when it is not needed or respond to an error with an inappropriate change of the control variable
changes to the requirements
cause of movement error where the required value of the controlled variable changes
cerebellar ataxia
genetic neurodegenerative disorder that affects one’s ability to walk (drunken gait), talk, and use fine motor skills
