Chap 1 Flashcards
(25 cards)
What are upper motor neurons?
Upper motor neurons are nerve cells that originate in the motor cortex of the brain and send signals to lower motor neurons.
What are lower motor neurons?
Lower motor neurons are nerve cells located in the spinal cord and brainstem that directly innervate skeletal muscles.
True or False: Upper motor neurons can directly stimulate muscle contraction.
False
Fill in the blank: The cell bodies of upper motor neurons are located in the ________ of the brain.
motor cortex
What is the primary function of upper motor neurons?
The primary function of upper motor neurons is to convey impulses from the brain to lower motor neurons.
What type of motor neuron is affected in amyotrophic lateral sclerosis (ALS)?
Both upper motor neurons and lower motor neurons are affected in ALS.
Multiple Choice: Which of the following is a characteristic of lower motor neuron lesions? A) Spasticity B) Flaccid paralysis C) Hyperreflexia
B) Flaccid paralysis
What is the role of lower motor neurons in the reflex arc?
Lower motor neurons are responsible for transmitting signals that result in muscle contraction during reflex actions.
True or False: Upper motor neuron lesions typically result in muscle atrophy.
False
What is the effect of upper motor neuron damage on muscle tone?
Upper motor neuron damage results in increased muscle tone or spasticity.
Fill in the blank: The axons of lower motor neurons exit the spinal cord via the ________ roots.
ventral
What are the two main types of upper motor neuron pathways?
The corticospinal tract and the corticobulbar tract.
Multiple Choice: Which condition is characterized by upper motor neuron signs? A) Guillain-Barré syndrome B) Stroke C) Myasthenia gravis
B) Stroke
What is the primary neurotransmitter used by lower motor neurons to stimulate muscle contraction?
Acetylcholine
True or False: Lower motor neuron lesions will result in increased reflexes.
False
What type of paralysis is associated with lower motor neuron damage?
Flaccid paralysis
Fill in the blank: Upper motor neurons synapse with lower motor neurons in the ________.
spinal cord
What is Babinski’s sign, and what does it indicate?
Babinski’s sign is an upward response of the big toe when the sole is stimulated, indicating upper motor neuron damage.
Multiple Choice: Which of the following is NOT a sign of upper motor neuron damage? A) Weakness B) Atrophy C) Hyperreflexia
B) Atrophy
What is the difference between voluntary and involuntary movements in relation to upper and lower motor neurons?
Voluntary movements are primarily controlled by upper motor neurons, while involuntary movements are mediated by lower motor neurons.
True or False: Upper motor neurons originate in the spinal cord.
False
What is the clinical significance of distinguishing between upper and lower motor neuron lesions?
It helps in diagnosing the location and type of neurological disorder.
Fill in the blank: The ________ tract is primarily responsible for voluntary motor control from the cortex to the spinal cord.
corticospinal
What happens to reflexes in the case of lower motor neuron damage?
Reflexes are diminished or absent.
