4 - Sensory Systems

Question 1

signal transduction

Answer 1

how the physical world turns into electricity & chemical signals in the brain

Question 2

receptive field

Answer 2

area from which a stimulus can activate a sensory receptor

Question 3

rapidly adapting receptors

slowly adapting receptors

Answer 3

• respond at the onset of a stimulus
• respond for the duration of a stimulus

Question 4

rods

Answer 4

• type of receptor cell in the eye
• rapidly adapting
• sensitive to dim light
• low response threshold

Question 5

cones

Answer 5

• type of receptor cell in the eye
• slowly adapting
• sensitive to color & position
• high response threshold

Question 6

exteroceptive receptors vs. interoceptive receptors

Answer 6

respond to external stimuli vs. internal stimuli

Question 7

suprachiasmatic nucleus

Answer 7

• in the hypothalamus
• controls circadian rhythms of feeding & sleeping in response to light

Question 8

pineal gland

Answer 8

controls long-term circadian rhythms through the release of melatonin

Question 9

geniculostriate pathway

Answer 9

• pathway from retina to visual cortex
• pattern, color, & motion recognition

Question 10

tectopulvinar pathway

Answer 10

• 2nd main visual pathway
• helps detect & orient visual stimulation

Question 11

visual-form agnosia

Answer 11

• inability to recognize objects
• caused by damage to the geniculostriate pathway

Question 12

visual ataxia

Answer 12

• inability to recognize where objects are located
• caused by damage to the tectopulvinar pathway

Question 13

nociception

Answer 13

• perception of pain, temperature, & itch
• pain is perceived in the CNS

Question 14

haptic receptors

Answer 14

• enable fine touch & pressure
• located in both superficial & deep skin layers

Question 15

proprioception

Answer 15

• perception of body location & movement
• encapsulated nerve endings sensitive to stretch of muscles & tendons, & to joint movements

Question 16

posterior spinothalamic tract

Answer 16

• one of 2 major somatosensory pathways
• for hapsis & proprioception
• fibers of somatosensory neurons are large, heavily myelinated, & rapidly adapting

Question 17

anterior spinothalamic tract

Answer 17

• one of 2 major somatosensory pathways
• for nociception
• fibers of somatosensory neurons are small, less myelinated, & slowly adapting

Question 18

Brown-Séquard Syndrome

Answer 18

• occurs when a unilateral spinal cord injury cuts somatosensory pathways in that 1/2 of the spinal cord
• causes loss of hapsis & proprioception unilaterally, & loss of nociception contralaterally

Question 19

homunculus

Answer 19

a topographic map that represents the body surface on the primary somatosensory cortex

Question 20

sensation

Answer 20

the registration of the sensory systems of physical/chemical energy from the environment & its transduction into nervous-system activity

Question 21

perception

Answer 21

the subjective interpretation of sensation by the brain

Question 22

synesthesia

Answer 22

• ability to perceive a stimulus of one sense as the sensation of a different sense
• can be either projectors or associators