Sensory system pt1

Question 1

What is the job of the sensory system?

Answer 1

provide the brain with correct information

Question 2

What are general senses?

Answer 2

-receptors that are widely distributed throughout the body (skin, various organs, and joints)

Question 3

What are special senses?

Answer 3

-specialized receptors confined to structures in the head (eyes, ears, nose, and mouth)

Question 4

Large vs. small receptive fields: convergence

Answer 4

LARGE RECEPTIVE FIELD
-convergence creates large receptive fields
-many neurons converge together to one
-advantage: save a lot of neurons
-disadvantage: low resolution
SMALL RECEPTIVE FIELD
-disadvantage: need a lot of neurons to cover a small receptor
-advantage: high resolution
-low convergence

Question 5

CNS must distinguish 4 properties of a stimulus

Answer 5

1. nature/modality: what is it “sound, touch, light”
2. Location: where does the signal come from
3. Intensity: how big is the stimulus
4. Duration: when stimulus is on or off

Question 6

Lateral inhibition

Answer 6

to increase the contrast and help identify the location

Question 7

Sensory comes from neuronal response

Answer 7

ex: getting used to a smell and not being able to smell it anymore
no neuronal response
brain is too busy to pay attention to stimulus that don’t change

Question 8

Somatotopic organization

Answer 8

topographic map of body surface

Question 9

Pain receptors

Answer 9

-Mechanical nociceptors: crushing, cutting, pinching
-Thermal nociceptors: temperature extremes
-Polymodal nociceptors: all damaging stimuli