Ex Phys Chapter 3 Neural Control of Exercising Muscle

grey matter

The portions of the central nervous system that are abundant in cell bodies. Unmyelinated.

white matter

myelinated axons

frontal lobe function

general intellect, motor control

temporal lobe function

auditory input, interpretation

parietal lobe function

general sensory input, interpretation

occipital lobe function

visual input, interpretation

insular lobe function

emotion, self-perception

basal ganglia function

initiation of sustained or repetitive movements like walking, running, or posture

thalamus function

serves that sensory relay center, determines what we are consciously aware of, "filter"

hypothalamus function

maintain homeostasis and regulate internal environment such as BP, HR, breathing, and body temp

function of the cerebellum

find tune of our movements by controlling rapid, complex movements and coordinating timing and sequence of movements

damage to the cerebellum...?

ataxia, poor muscle control that causes clumsy movements

what makes up the brain stem

midbrain, pons, medulla

function of the brain stem

info relay between brain and spinal cord

reticular formation function

coordinates skeletal muscle function and tone... adjusts muscle tone. controls cardiovascular and respiratory function

analgesia (pain control) system

releases of beta-endorphin with exercise

vagus nerve function

responsible for movement, sensation and abdominal organs

there are ____ pairs of spinal nerves

31

joint kinesthetic receptors

proprioceptors that monitor joint position and motion

how does the autonomic nervous relate to exercise?

when our sympathetic cardiac nerve fires and we enter fight or flight, heart rate, blood pressure, and vessel diameter are effected

how does the vagus nerve impact parasympathetic nervous system?

but inserting the vagal one on the SA/AV node while slows down depolarization (ie lowering HR)

what is the definition of sensory-motor integration

the communication and interaction between sensory and motor systems

describe the 5 sequential steps of sensory-motor integration

1.Stimulus sensed by sensory receptor.

2.Sensory AP sent on sensory neurons to CNS.

3.CNS interprets sensory information, sends out response.

4.Motor AP sent out on a-motor neurons.

5.Arrives at skeletal muscle and

response occurs

-what type of response occurs when the spinal cord is the integration site?

-Give example

-and the key idea

-simple, automatic motor reflexes.

-knee-jerk reflex,

-fastest response, no conscious involvement

-what type of response occurs when the lower brainstem is the integration site

-Give example

-and the key idea

-subconscious motor reactions

-sitting upright, standing balance

-more complex than spinal but still unconcious

-what type of response occurs when the cerebellum is the integration site

-give example

-and the key idea

-Subconscious coordination of movement

-smooth walking, precise hand movements

-without cerebellar control, the movement will become uncoordinated

-what type of response occurs when the thalamus/spinothalamic tract is the integration site

-give example

-and the key idea

-entry into consciousness

-awareness of touch, pressure, temperature

-sensations are recognized but not precisely localized

-what type of response occurs when the cerebral cortex is the integration site

-give example

-and the key idea

-conscious perception, voluntary motor control

-knowing exactly where you were touched, deliberate movement

-highest level of control, precise localization, complex thought

motor reflex

-Instant, preprogrammed response to stimulus

-Response to stimulus identical each time

-Before conscious awareness

what are the five lobes of the cerebrum and their general function

Frontal lobe: general intellect and motor control

Temporal lobe: auditory input and interpretation

Parietal lobe: general sensory input and interpretation

Occipital lobe: visual input and interpretation

Insular lobe: diverse functions usually linked to emotion and self-

perception

primary motor cortex

response for the control of fine and discrete muscle movements. the part of the brain where decisions about what movement one want to make are made

the neurons within the primary motor cortex are ______

pyramidal cells

cerebrum

the conscious brain that allows people to think, be aware of sensory stimuli, and voluntarily control their movements

How does the cerebellum integrate intended motor commands with sensory feedback related to body position and muscle status to coordinate movement?

by. comparing the programmed or intended activity with the actual changes occuring in the body and then inititating corrective adjustments through the motor system.

reticular formation

a specialized collection of neurons in the brain stem that help:

-coordinate skeletal muscle function,

-maintain muscle tone,

-control cardiovascular and respiratory functions, and

-determine state of consciousness (arousal and sleep).

how do the brain and spinal cord differ in their roles in sensory processing, motor control, and integration

the brain is more responsible for the integration of information whereas the spinal cord can be thought of as the track where sensory and motor information go up and down

what do free nerve endings detect?

crude touch, pressure, pain, heat, and cold

what are the 3 levels where a motor response can originate?

-the spinal cord

-the lower regions of the brain

-the motor area of the cerebral cortex

muscle spindles have an abundant amount of actin and myosin filament (T/F)

false

what motor neuron innervates the muscle spindle

gamma- motor

how do muscle spindles contribute to fine motor control and protection against excessive muscle lengthening

by sending continuous feedback on the exact length of the muscle and the rate at which the length is changing

what are the 2 type of muscle afferent nerves that activated with the onset of exercise and what are their distinctions

group III - thinly myelinated and mostly sensitive to mechanical stimuli

group IV - unmyelinated and chemosensitive

how do muscle afferent nerves influence cardiovascular regulation, motor neuron output, fatigue, and injury prevention?

by signaling to the CNS to facilitate oxygen and, therefore, ATP delivery to the muscle. Also, can modulate motor neuron output which can prevent central fatigue and muscle injuyr

what are the motor neuron to muscle fiber ratio of the eye? Gastroc?

1:15, 1:2000

muscle fibers in a specific motor unit are _____ with respect to fiber type

homogenous

motor unit

A motor neuron and all of the muscle fibers it innervates

It is possible to find a motor unit with both type 1 and type 2 muscle fibers (T/F)

false