Neuro Wk 9

Match the UMN & LMN cell bodies and axons with where they are located.

UMN Axons

Form the ventral root for the nerve at the specific segment

LMN Cell Body

Above the ventral/anterior horn in spinal cord

LMN Axons

Ventral horn of all spinal segments and motor nuclei in the brainstem

UMN Cell Body

White matter tracts in the cortex

Denervation of muscles, hyporeflexia, paresis/paralysis, atrophy, loss of muscle tone, and fibrillations are symptoms of what?

UMN lesions

LMN lesions

For both UMN and LMN lesions, the distribution is below level of the lesion.

True

False

Match the medial motor tract to its function

Medial + lateral vestibulospinal tracts

Receive info about head movement/position from vestibular apparatus and responds to gravity info from vestibular apparatus

Reticulospinal tract

Facilitates LMNs innervation postural and gross limb movement muscles throughout the body

Medial corticospinal tract

Direct connection from cerebral cortex to spinal cord (neck, shoulder, trunk mm.)

Describe the order of the corticospinal pathway starting with where the first order neuron originates.

Internal capsule

Cerebral peduncles (midbrain)

Anterior pons

Pyramids (medulla)

Pyramidal deccusation occurs for about 88% of axons

Synapse with lower motor neurons in spinal cord

LMN travel to muscles of the limbs

If there were a lesion at the X, what would be affected?

Left upper limb

Right upper limb

Left upper and lower limb

Right upper and lower limb

Bilateral destruction of UMNs and LMNs is the definition of what disease?

Multiple Sclerosis

Babinskis

Amyotrophic Lateral Sclerosis

Postpolio Syndrome

Muscle weakness, joint and muscle pain, fatigue, and breathing problems are all signs of what?

Multiple Sclerosis

Babinskis

Amyotrophic Lateral Sclerosis

Postpolio Syndrome

Select all of the primary functions of the peripheral nervous system.

Connect CNS to organs, limbs, and skin

Carry sensory and motor information to/from the CNS

Allow the brain and SC to send or receive information

Regulate involuntary body functions

What most accurately describes sensory neurons?

Afferent fibers with long dendrites that transmit information to the cell bodies in dorsal root ganglion

Efferent fibers with long axons that transmit information in the ventral horn

Afferent fibers with long axons that transmit information to cell bodies in dorsal root ganglion

Efferent fibers with long dendrites that transmit information in the ventral horn

Dermatome involvement indicates what?

A peripheral nerve is damaged

A spinal nerve root is damaged

A group of muscles has become denervated

Mechanoreceptors, thermoception, proprioceptors, nociception are all somatosensory receptors.

True

False

Match each type of mechanoreceptor to its primary function.

Fast-adapting receptors continue responding to constant stimulus; detects size and shape of objects.

True

False

A receptive field is an area where sensory stimuli can modulate firing of sensory neurons.

True

False

How does receptive field relate to mechanoreceptors?

If the RF is smaller, there is higher resolution or more precise information for receptors.

If the RF is larger, there is higher resolution or more precise information for receptors.

There is no relation.

Meissners Corpuscle and Merkel's Discs use smaller RFs than Pacinian Corpuscles and Ruffinis ending.

True

False

Somatosensory system pathways are always what?

Single order neuron pathways

Two order neuron pathways

Three order neuron pathways

Four order neuron pathways

Match the order of neuron to its general start and end point for somatosensory systems.

Two-point discrimination, graphaesthesia, and stereognosis are carried out by which pathway?

Anterolateral spinothalamic tract pathway

Dorsal column medial lemniscus pathway

Corticospinal tract

The anterolateral spinothalamic tract pathway is responsible for what?

Sharp pain and temperature

Proprioception

Fine touch

Motor control

The image describes which pathway?

Somatosensory tract

Medial lemniscus pathway

Lateral corticospinal tract

Spinothalamic tract

Neuro Wk 9

More Surveys