Control Of Body Movement

Front 1

Descending Tracts

Back 1

axons carrying motor commands from the brain to the PNS majority are anterior and lateral , usually involve 2 neurons

Front 2

Upper Neuron

Back 2

extends from motor cortex or motor nuclei in the cerebrum to the anterior horn

Front 3

Lower Neuron

Back 3

lie in anterior horn and travel to the effectors in the periphery

Front 4

Spinal Cord Trauma

Back 4

Paralysis

Flaccid Paralysis

Front 5

Paralysis

Back 5

loss of motor function

Front 6

Flaccid Paralysis

Back 6

severe damage to the ventral root or anterior horn; lower motor neurons damaged and impulses don't reach, no voluntary or involuntary control of muscles

Front 7

Spastic Paralysis

Back 7

only upper motor neurons of the primary cortex are damaged; spinal neurons intact and muscles are stimulated regularly, but no voluntary control of muscles, exxgerated reflexes

Front 8

Reflexes

Back 8

rapid predictable motor responses to a stimulus

Front 9

Where do Reflexes occur?

Back 9

spinal cord or brain

Front 10

Are all reflexes innate?

Back 10

no some are learned

Front 11

What 2 types of reflexes are there?

Back 11

somatic

Visceral

Front 12

Monosynaptic

Back 12

1 Synapse sensory synapses directly with motor neuron

Front 13

Polysynaptic

Back 13

2 or more synapses; sensory synapses with interneuron which then would synapse with motor neuron

Front 14

Why are reflexes important clinically?

Back 14

exaggerated or absence of reflexes can indicate neurological problems

Front 15

Components of a Reflex Arc

Back 15

1. Receptor

2. Sensory Neuron

3. Integration

4. Motor Neuron

5. Effector

Front 16

Receptor in reflex arc does what?

Back 16

Detects stimuli

Front 17

Sensory Neuron does what in a reflex arc?

Back 17

Relays info to CNS

Front 18

Integration does what in reflex arc?

Back 18

Interprets info; may be spinal cord or brain

Front 19

Motor Neuron does what in a reflex arc?

Back 19

Carries the response form CNS to the effector

Front 20

Effector is what in a reflex arc?

Back 20

Muscle or gland

Front 21

Examples of Somatic Reflexes via Spinal Cord

Back 21

Stretch Reflex

Flexor Withdrawal Reflex

Superficial Refexes

Front 22

Stretch Reflex

Back 22

Muscle spindles are stretched and excited, afferent impulse is sent to spinal cord where it synapses DIRECTLY with motor neuron that triggers the muscle to contract (serial);

Sensory neuron also synapses with an interneuron that inhibits the motor neurons of the antagonist muscles this is called reciprocal inhibition

Front 23

Reciprocal inhibition

Back 23

Sensory neuron that is stimulated by stretch synapses with a interneuron that inhibits motor neurons of antagonist muscles

Front 24

Flexor Withdrawal (Reflex)

Back 24

initiated by painful stimulus and causes withdrawal of a body part

Front 25

Examples of Flexor (Withdrawal) Reflex

Back 25

touch of something hot , abdominal reflex

Front 26

Superficial reflexes

Back 26

initiated by cutaneous stimulation

Front 27

Example of a superficial Reflex

Back 27

Plantar Reflex

Front 28

Muscle spindle

Back 28

Sensory neuron free nerve ending wrapped around skeletal muscle

Front 29

What part of the brain always knows what muscles are stretched and what position they are in?

Back 29

Cerebellum

Front 30

Where are most autonomic (visceral) reflexes processed?

Back 30

brain stem

Front 31

Examples of autonomic or visceral reflexes

Back 31

Cardiac muscle
smooth muscle
glands

Front 32

Somatic reflexes

Back 32

effector is skeletal muscle