539 Test from my notes

primitive reflexes

-based on survival

-simple motor response to a stimulus ( you do a, b happens)

-present in utero or at birth

-initial reflexive movements gets replaced by voluntary movements

-transitions head to feet, proximal to distal

reflexes

-original purpose is survival, seeking food, startling in case of danger

-lays the groundwork for gross motor movements

• these are out of your control

reactions

-Protective: important to check bilaterally (ie, moro)

-equilibrium: how body moves through space, maintains center of gravity (helps you stay in place)

-Balance/righting: gets us into/out of motion while keeping the body upright

• you chose to do these

tonic responses

-critical for stability

-muscle tone and holding a position

phasic responses

-develops our movement patterns

-segmental/clunky at first, then becomes more fluid—> how we get somewhere

obligatory/retained responses

when reflexive reactions are still present

purpose for Labrinthine/optical (head) righting

-visual acuity, orientation, postural stability

What plays into our stability so we can move our extremities?

-abs/core muscles, good posture

what helps us know where our extremities are?

-proprioception, vision, tactile, interoception

fine motor development in the hand

-starts ulnar and moves radially (thumb side)

-starts inefficient and becomes more precise with time and practice

• palmar grasp to pincer grasp

• we often compensate with poor manipulation skills by using both hands

which writing grasps are considered mature?

-static tripod grasp (3-4 years)

-static quadrupod grasp (3-4 years)

what grade would you typically stop trying to correct someones grasp pattern as long as it was functional?

2nd

in hand manipulation - shift

moving an object from one hand to another

in hand manipulation- rotation

turning object in hand

in hand manipulation- simple rotation

slight rotation

in hand manipulation- complex rotation

end over end rotation

development of hand prefernce

-by age 3 or 4 we typically see a hand preference

-if not by age 7, they fall into ambidextrious category and we are now concerned about low tone

-we can also see a preference as early as 2 but that has concerns

gross motor skills

-large muscle groups

-develops first and recovers faster than fine motor

fine motor skills

-small muscle groups

stability comes ____ mobility

before

motor control theory

“the ability to regulate or direct the mechanisms essential to movement”

• x leads to y

motor learning theory

“ a set of processes associated with practice or experience leading to relatively permanent changes in the capability for skilled movement”

• trial and error

reflex theory

complex patterns of movement are the result of combining individual reflexes, movements are the response to a stimulus

early learning new skills

-focus is on strategies that will gain you success

-not usually the most effective strategy

-a sort of pruning occurs where less effective strategies are discarded for more effective ways

later learning new skills

-focus begins on adjusting how skills are performed

-goals are consistently achieved

-more precise, efficient results are expected

development of anti-gravity movement

-development of movement against gravity

-develops in prone (on stomach) and supine (on back), before strengthening in sitting and standing postures

-starts medially then moves distally (close then moves out)

rehab following injury

-many gross motor develops (power), then fine motor development follows (precision)

-stages of new learning will still apply

• new learning (will still be less efficient, more trial and error)

• refined learning (focuses on efficiency, will refine skills and preferences)

alpha motor neurons (lower motor neurons)

-innervate extrafusal skeletal muscle fibers

-cell bodies located in the ventral horn of the spinal cord or the motor nuclei of cranial nerves

• axons travel in ventral roots and out through spinal/cranial nerves

innervation

-one alpha motor neuron innervates multiple muscle fibers

-BUT, one muscle fiber is innervated by only one alpha motor neuron

-forms a function unit called a motor unit which is one nerve and all the fibers it innervates

motor units

-muscles that control fine movements have small motor units

-large weight-bearing muscles have large motor units

fast twitch glycolitic

-contain muscle fibers capable of rapidly attaining full contraction

-fatigue quickly

-produces greatest force of contraction

-fastest response w/greatest force

fast twitch oxidative

-contain muscle fibers capable of rapidly attaining full tension

-fatigue less quickly

-maximal force of contraction is ½ of fast fatigable units

slow twitch oxidative

-contain muscle fibers that attain full tension more slowly

-fatigue very slowly

-maximal force of contraction is much less

-most minimal output

neuromuscular junction

-synapse between single axon terminal with single muscle fiber

• Acetycholine (ACh) receptors

• Nicotinic ACh receptors (skeletal muscles)

end-plate potentials

when ACH binds nicotinic-ACh receptors in sub-synaptic sarcolemma and it it makes this exitatory synapse

Voltage gated (Na+ and K+) channels support APs in muscle

that travel away from the end plate

acetylcholinesterase

prevents continued muscle fiber contraction in the absence of additional stimuli

recruitment

adding more motor units

Brodmanns Area 4

Primary motor cortex (M1, aka. 4, precentral gyrus)

Brodmann’s area 6

-premotor area (PMA)

-supplemental motor area (SMA)

M1

-serves as principle motor output to lower motor neurons and local circuit interneurons of brain/cord

• Brodmann’s area 4

Inputs to M1

1. SMA

2. PMA

3. thalamus

4. S1 (sensory)

5. posterior parietal cortex

Inputs into PMA and SMA

-basal ganglia via thalamus

-cerebellum via thalamus

-prefrontal cortex (association area)

-posterior parietal cortex (association area)

• functions to make meaningful perceptual experiences

• abstract thought, language

basal ganglia composed of:

-caudate nucleus

-putamen

-globus pallidus

-substantia nigra

-subthalamic nucleus

caudate nucleus

-heavily involved in higher motor control

-learning and memory

-language comprehension and articulation

putamen

• is a control freak lol

• controls movements via interaction with other basal ganglia structures

substantia nigra

-roles in:

• reward

• learning

• addiction

• MOVEMENT

• MOTOR PLANNING

general rules of basal ganglia (VERY IMPORTANT)

-increased BG output leads to slow/controlled movements

-decreased (no) BG ouput leads to involuntary movements during rest

cerebellum

-”little brain”

-sensory perception into movements

-coordination/motor control

• “fine-tuning”

-corregated cortex in two hemispheres seperated by vermis

cerebellar inputs

from the:

-parietal cortex

• sensory and association areas

-motor cortex

-prefrontal cortex

cerebellar outputs

-output from the vermis communicates with structures in the brainstem

• helps control axial movements

-output from hemispheres

• adjustment controls output of M1

• M1 by itself makes big movements and w/o cerebellum they would NOT be precise

cerebellar functions

1. motor memory

2. Integration of information as motor activity is progressing

which brain structures are important in motor processing?

basal ganglia, thalamus, cerebellum, parietal cortex, primary sensory cortex, and motor cortex

vestibulospinal tract

allows for maintenance of head position relative to gravity as body changes

• ex. when you go on rollercoasters or do headstands, your head tries to right itself

tectospinal tract

-head and eyes oriented toward visual stimulus

pontine reticulospinal pathway

coordination of anti-gravity reflexes

medullar reticulospinal pathway

• liberates anti-gravity muscles from reflex control of pontine reticulospinal pathway

• aka makes you do what you are not supposed to be doing (reflex wise)

lateral pathways

voluntary muscle controls

ventromedial pathways

-head orientation relative to gravity or visual stimulus

-anti-gravity reflex

-overcoming anti-gravity reflexes

skeletal muscle functional factors

1.number of fibers involved

-the more the greater the strength

2.firing rate of a-motor neurons

-the higher the rate (frequency of signaling), the greater the strength output

3.number of motor units utilized

-the more the greater the strength

4.types of motor units present

5. sequence of motor unit activation