Exam 3 Questions Flashcards
In the somatosensory system…
Receptors on the distal end of the peripheral processes of dorsal root ganglion neurons contain stretch sensitive ion channels.
In the sensory system, the largest diameter axons convey information on…
proprioception from skeletal muscle.
Sensory receptors transduce physical stimuli into electrical signals called the _____ potential in response to skin distortion.
receptor
Which of the 4 skin receptors is defined as being fast adapting with a large receptive field?
Pacinian Corpuscle
Details related to perception and transmission of PAIN information.
Many C fibers are polymodal.
Tactile form perception?
Merkel’s Disk
Most sensitive to vibration?
Pacinian Corpuscle
Fine tactile discrimination?
Meissner Corpuscle
Detects movement over skin?
Ruffini Corpuscle
Which area is involved in modulation of painful stimuli?
Periaqueductal Gray
In the gate theory of pain, mechanosensitive afferents (Aβ) excite ______ interneurons that synapse on dorsal horn neurons giving rise to the ______ tract.
In the gate theory of pain, mechanosensitive afferents (Aβ) excite inhibitory interneurons that synapse on dorsal horn neurons giving rise to the spinothalamic tract.
Regarding the sensory cortex,
lesions of Area ___ would result in deficits in perceiving the location of a cutaneous stimulus.
Area 3
Meissner’s Corpuscles are located…..
in the SUPERFICIAL layer of the dermis
When a patient is unable to carry out movements of the face on demand, but are able to spontaneously or reflexively contract the same muscle, they are said to have ______ (be specific).
Buccofacial Apraxia
Which of the structures we studied in this unit, if damaged as the result of stroke, would result in a patient denying the contralateral side of his/her body.
Association Areas 5 and 7 of the Parietal Cortex
Which of Brodmann’s Areas of the primary somatosensory cortex (S1) receives the largest projection from the Ventral Posterior Lateral (VPL) nucleus of the thalamus?
Area 3
TRUE or FALSE?
Secondary Somatosensory Cortex receives its largest input from the VPL/VPM of the thalamus.
FALSE
TRUE or FALSE?
A person with tactile agnosia will use objects inappropriately (use a screwdriver as a pen).
FALSE
TRUE or FALSE?
Patient GL, who lost her large sensory axons in spinal nerves, could still perceive painful stimuli.
TRUE
TRUE or FALSE?
The affective component of painful stimuli is processed in the cingulate cortex.
TRUE
Give rise to form axons that form the Optic Nerve:
Retinal ganglion cells
Regarding neural transmission in the retina,
When light strikes photoreceptor cells, off-center bipolar cells are ______ .
hyperpolarized
Regarding “complex cells” in the primary visual cortex,
The receptive field is determined by the input of ____ .
multiple simple cells
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Which of the 2 types of ganglion cells has a higher sensitivity to color contrast?
P type ganglion cells
This type of cell in the primary visual cortex is primarily concerned with perceiving color:
A. Simple Cells
B. Complex Cells
C. Blobs
Blobs
A motor unit consists of what 2 structures?
An alpha motor neuron and all the fibers that it innervates.
TRUE or FALSE?
A spinal nerve contains both afferent and efferent axons.
TRUE
!!!!!!!!
TRUE or FALSE?
Motor neurons that innervate flexor muscles are located dorsal to motor neurons that innervate extensor muscles in the ventral horn of the spinal cord.
TRUE
TRUE or FALSE?
A large motor unit allows for more precise control of muscle activity.
FALSE
TRUE or FALSE?
The force of contraction of individual muscle fibers is determined by the firing rate of a motor neuron.
FALSE
!!!!!!!!???????
A sustained muscular contraction induced by high firing frequency of a motor neuron is called ____
Tetany
Muscle spindles are innervated by __ ____ axons.
Aα afferent
In the flexor reflex, ….
Flexor reflex afferents synapse on interneurons that inhibit antagonist muscles.
Gamma Motor Neurons:
Innervate INTRAFUSAL Muscle Fibers
The Corticospinal Tract arises from neurons in the …..
precentral gyrus of the frontal lobe
Axons in the Corticobulbar Tract synapse on neurons in the _____
Hypoglossal nucleus
The mast majority of the _____ is buried in the central sulcus and forms its anterior wall.
primary motor cortex
TRUE or FALSE?
Descending axons from the cerebral cortex and brainstem modulate spinal reflexes.
TRUE
!!!????
TRUE or FALSE?
Loss of Lower Motor neurons results in spastic paralysis of muscles.
FALSE
TRUE or FALSE?
Neurons in the facial motor nucleus are defined as lower motor neurons
TRUE
TRUE or FALSE?
Neurons in the Primary Motor Area (M1) are primarily active during the planning of a movement.
FALSE
The Premotor Cortex is active when _____.
Planning a movement
The Supplementary Motor Cortex is active when _____
doing activities such as playing the piano
The Lateral Corticospinal Tract Synapses ……
directly on muscles controlling digits.
The Anterior Corticospinal Tract Synapses……
on motor neurons that innervate trunk muscles
An occlusion of a branch of the anterior cerebral artery to the right precentral gyrus would result in…..
Paralysis of the muscles in the left leg and ankle.
Where are the neurons whose axons form the spinothalamic tract located?
The Dorsal HORN of the Spinal Cord
!!!!!!!!!!!!!!!
Which Trigeminal Nuclei contain neurons that relay discriminative touch and vibration information to the thalamus?
Main Sensory of V
!!!!!!!!!!!!!!!!!!
Preganglionic Sympathetic Neurons that are involved in regulating melatonin release are located in the:
Thoracic Spinal Cord
