Ch 15

Question 1

3 sensory receptor types

Answer 1

Exteroceptors - monitor external enviro (touch, pressure, pain, balance)
Interreceptors - monitor visceral organs
Proprioceptors - monitor position of skeletal muscles & joints (body position in space)

Question 2

visceral sensory info goes to

Answer 2

diencephalon

Question 3

sensory receptors

Answer 3

structures that monitor changes in specific variables inside & outside the body

Question 4

Receptor Specificity

Answer 4

each receptor responds to specific type of stimulus (pressure recept. are stim. by pressure)

usually specific receptors are at end of an afferent neuron

Question 5

2 types of senses

Answer 5

general and special

Question 6

General Senses

Answer 6

temp, pain, touch, pressure, vibration, proprioception (muscle stretch)

Question 7

General Sense Receptors are at

Answer 7

are usually at the dendrite ends of an afferent (sensory) neuron

Question 8

Free nerve endings sense…

Free nerve endings feel free to detect anything: ouch! that’s hot

Answer 8

pain, touch, pressure, temp

all over epidermis and dermis (close to surface of skin)

Question 9

root hair plexus sense…

the root of a hair’s story is in its wiggle

Answer 9

movement in hair

wrapped around the base of hair follicles

Question 10

merkel cells and tactile discs sense…

merkel loves the fine details on her fingertips

Answer 10

fine touch, pressure

fingertips, lips, external genitalia

Question 11

ruffini corpuscle (bulbous) sense…

ruffini stretches to reach the roof on his fingers

Answer 11

distortion, skin stretch and sustained pressure

deep in the dermis and around joints and fingers

Question 12

lamellated corpuscle (pacinian) sense…

pac-man likes to feel the deep vibration of his power pellets

Answer 12

deep pressure, and high freq vibrations

deep in the dermis, often in palms, soles, and joints

Question 13

tactile corpuscle (meissner’s) sense…

meissner massages with soft fingers on hairless skin

Answer 13

light touch, and low freq vibrations

hairless areas like fingertips, palms, soles, lips, and nipples

Question 14

Special Senses

Answer 14

olfaction (smell), vision, gustation (taste), equilibrium (balance), hearing
receptors are more complex; located in sense organs (eg. eye, ear, tongue, etc)

Question 15

Detection of the stimulus

Answer 15

an adequate stimulus acting on a sensory receptor causes a change in the membrane’s permeability, which leads to the generation of the receptor cell’s graded depolarization/hyperpolarization = Receptor Potential

Question 16

Generator Potential

Answer 16

a depolarization of the sensory neuron

Question 17

Transduction

Answer 17

process of translating stimulus into an action potential
eg. picking up touch and converting to electrical impulse

Question 18

Receptive field

Answer 18

are of body monitored by one particular afferent neuron and all its receptors

Question 19

Range of Detection

Answer 19

the # and type of sensory receptors we have limit what we can sense and become aware of

Question 20

to generate conscious sensation, sensory info must be transmitted to

Answer 20

the cortex

Question 21

Sensation

Answer 21

raw experience; may be unconscious
- activity in any/all sensory neurons

Question 22

Perception

Answer 22

SNS (somatic nervous sys) interpretation (1% of all sensation), meaning given to sensation, conscious awareness of sensation
- activity in cerebral cortex and not just spinal cord/brain stem

Question 23

Not Perceived:

Answer 23

visceral sensory info delivered to diencephalon, spinal cord & brain stem only

Question 24

Labelled Line:

Answer 24

pathway that conducts sensory info from a receptor to specific neurons in cortex

Modality (type) of stimulus (eg. touch, pressure, temp, sound) is interpreted here

Question 25

Information about type, strength, duration, and variation of stimuli is coded by:

Answer 25

a) **Type of sensory receptor** cell activated b) **The rate of action potentials generated

Question 26

The ______/________ the stimulus, the ____ action potentials generated (APs more _______)

Answer 26

**harder/stronger** the stimuli, the **more** AP generated (APs more **frequent**)

Question 27

Sensory coding begins at the

Answer 27

sensory receptors

Question 28

Tonic Receptors

Answer 28

always active provide information about: - background lvl stimulation - changes indicated by frequency of APs generated - called **slow-adapting receptors** b/c they show **little peripheral adaption**

Question 29

Phasic Receptors

Answer 29

**not always active**, fire only when stimulated provide info about: - intensity/rate of change by stimuli - called **fast-adapting receptors** b/c they respond strongly at first and then show decline in activity = **peripheral adaptation**

Question 30

Central Adaptation eg.

Answer 30

smell

Question 31

Peripheral Adaptation eg.

Answer 31

thermoreceptors

Question 32

Tonic Receptors Examples

Answer 32

- ruffini corpuscle - merkel tactile receptors - nociceptors - joint capsule proprioceptor - muscle spindle

Question 33

Phasic Receptors Examples

Answer 33

- pacinian corpusles - meissner's corpuscles - thermoreceptors - root hair plexuses