Neuro Exam 1 Integrative

Which best defines nociception

Neural encoding and processing of noxious stimuli

What best describes nociceptors

Free nerve endings found in skin muscle joints bone and viscera

Which fiber type mediates first fast sharp pain

A delta fibers

Which does NOT directly activate TRPV1 channels

Prostaglandins

Which axon type has the slowest conduction velocity

C fibers

Which mechanoreceptor is rapidly adapting and detects vibration

Pacinian corpuscle

How is the dorsal root ganglion neuron classified

Pseudounipolar

Which receptor primarily signals muscle tension

Golgi tendon organ

Which pathway carries discriminative touch

Dorsal column medial lemniscal system

The VPM nucleus of the thalamus relays sensory input from where

Face

Type II A delta nociceptors respond best to what

Thermal heat stimulation

Which Rexed laminae receive primary nociceptive input

Laminae I II and V

Where do second order neurons cross in the anterolateral system

Level of the spinal cord

What is hyperalgesia

Increased sensitivity to painful stimuli

What is wind up

Increased excitability of dorsal horn neurons

Which tract contributes to affective motivational aspects of pain

Spinoreticular tract

What causes allodynia

Central sensitization allowing innocuous stimuli to activate pain pathways

Which photoreceptor mediates scotopic vision

Rods

What mediates the dark current in photoreceptors

cGMP gated sodium calcium channels

What effect does light have on photoreceptors

Hyperpolarization

Which fibers travel in Lissauer tract

Pain and temperature afferents

A unilateral spinal cord lesion causes what pattern

Contralateral pain loss ipsilateral touch loss

What does the fasciculus gracilis carry sensory information from

Lower body

How are Group Ia afferents best described

Rapidly adapting large myelinated fibers

Which receptor is slowly adapting and encodes sustained pressure

Ruffini ending

The medial lemniscus forms after synapse in which structure

Medulla

Which structure lacks photoreceptors and creates the blind spot

Optic disc

What is the fovea specialized for

High visual acuity

Which retinal cells provide lateral inhibition

Horizontal cells

ON center ganglion cells increase firing when what occurs

Light increases in the center

Which cone type is absent from the foveola

S cones

What causes deuteranopia

Loss of medium wavelength cones

Which retinal cells fire action potentials

Ganglion cells

Myopia occurs when the focal point falls where

In front of the retina

Accommodation for near vision requires the lens to do what

Become more curved

Capsaicin produces analgesia through what mechanism

TRPV1 desensitization

Which pathway orients the eyes and head toward painful stimuli

Spinotectal tract

Rapidly adapting mechanoreceptors primarily encode what

Changes in stimulation

Which neurons control intrafusal muscle fiber tension

Gamma motor neurons

What is unique about visceral nociceptors

They include silent nociceptors

Paleospinothalamic pathways are associated with what type of pain

Dull burning pain

Which thalamic nucleus relays body touch information

VPL

How is the visual image formed on the retina

Inverted and curved

Cataracts impair vision by affecting which structure

Lens

How do rods differ from cones

Rods are extremely light sensitive

Central sensitization allows what phenomenon

Innocuous stimuli to produce pain

Which structure contains sensory neuron cell bodies

Dorsal root ganglion

What type of potential is characteristic of sensory receptors

Graded

What does plasticity in primary somatosensory cortex refer to

Functional expansion after repeated stimulation

How is the primary somatosensory cortex organized

Columns as functional module