Sensory Physiology

Front 1

-receptors spread throughout entire body
-taste, smell, hearing, vision

Back 1

general senses

Front 2

-detect stimulus (often neurons)
-convert chemical or physical stimulus ino nerve signal
-some are neurons and some stimulate neurons

Back 2

sensory receptors

Front 3

neurons+ other tissues (CT, muscle) that enhance response
ex: ear, eye

Back 3

sense organs

Front 4

1. type of stimulus
-ex: vision via labeled line code

2. stimulus detected w/in receptive field

Back 4

1. modality

2. location

Front 5

1. determined by # nerve fibers activated and how fast they fire

2. how long stimulus lasts

Back 5

1. intensity

2. duration

Front 6

-area of body that leads to activity in a particular neuron
-stimulation anywhere in receptive field activates neuron
ex: back touched twice 6cm apart (only sense 1 touch)
-fingers: 2 touches 2mm apart (sense 2 touches)--2 point discrimination

Back 6

stimulus location

Front 7

-have larger receptive field
-hard to pinpoint stimulus

Back 7

visceral organs

Front 8

as pressure increases, the number of nerve fibers attached increases

Back 8

stimulus intensity

Front 9

1. -smell, hair, movement, clothes on skin

2. proprioceptors (sense body position)

Back 9

1. phasic receptors

2. tonic receptors

Front 10

-firing of nerves fibers gets slower over time
-become less aware of stimulus
-related to stimulus duration
ex: hot bath, elastic on socks, perfume

Back 10

sensory adapation

Front 11

1) touch, pressure, stretch, temp., pain
-skin, muscle, viscera

2) vision, hearing, equilibrium, taste, smell
-head, innervated by CNS

Back 11

1) general senses

2) special senses

Front 12

1) temperature

2) light

Back 12

1) thermoreceptors

2) photoreceptors

Front 13

1) pain

2) chemicals

Back 13

1) nociceptors

2) chemoreceptors

Front 14

-physical deformation
-vibration, touch, pressure, stretch

Back 14

mechanoreceptors

Front 15

1) external

2) internal organs

3) muscle, tendons, joints, sense body position and movement

Back 15

1) exteroceptors

2) interoceptors

3) proprioceptors

Front 16

-skin
-free nerve endings, tactile disc, hair receptor

Back 16

unencapsulated nerve endings

Front 17

-pain
-temp
-type of unencapsulated nerve endings

Back 17

free nerve endings

Front 18

-unencapsulated nerve ending
-light tough, pressure (tonic)

Back 18

tactile disc

Front 19

-type of unencapsulate nerve ending
-light tough
-hair movement
-phasic
-ex: dont feel clothing but feel bug crawling across skin

Back 19

hair receptor

Front 20

-touch, pressure, proprioception
-neurons wrapped in glia or CT
-tactile corpuscle, end bulb, bulbous corpuscle, lamellar corpuscle, muscle spindle, tendon organ

Back 20

encapsulated nerve endings

Front 21

type of encapuslated nerve endings for light touch
1) in skin and especially in sensitive hairless areas such as fingertips, palms, eyelids, lips, nipples, and genitals

2) found in mucus membranes of the lips and tongues, eye, and endoneurium of large nerves

Back 21

1. tactile corpuscle
2. end bulb

Front 22

type of encapsulated nerve endings
1) deep pressure, stretch, vibration
-in periosteum of bones, hands, feet, breasts, genitals

2) heavy touch, pressure, stretch
-dermis, subcutaneous tissue, joint capsules

Back 22

1) lamellar corpuscle

2) bulbous corpuscle

Front 23

type of encapsulated nerve endings involved with proprioception
1) stretch

2) tension

Back 23

1) muscle spindle
2) tendon organ

Front 24

-discomfort caused by inury or noxious stimulus
-leads to evasive action
-injured tissues release bradyin and prostaglandins that active norciceptors

Back 24

pain

Front 25

1) -info passes thru myelinated fibers 12-30 m/sec
-sharp pain

2) -via unmyelinated fibers 0.5-2m/sec
-dull pain

Back 25

1) fast pain

2) slow pain

Front 26

-pain in viscera thought to cme from elsewhere
-neural pathways converge on same interneurons in CNS
-brain cannot distinguish source so assumes most likely source
ex: T1-T5 receives input from heart, chest, arm

Back 26

referred pain

Front 27

ascending
pain on right side sensed on left side of the brain

Back 27

contralateral

Front 28

1) pain info transferred to limbic system (fear) and to where in brain

2) proprioception to where in brain

3) visceral info to where in brain

Back 28

1) hypothalamus

2) cerebellum

3) medulla oblongata

Front 29

-block pain transmission in SC so dont receive pain
ex: runners high, wounded soldier, women in child birth

Back 29

endogenous opioids

Front 30

-chemicals stimulate taste cells within taste buds
-salty, sweet, sour, bitter, umami
-perceived taste is combo of 5 tastes + smell + sight + texture

Back 30

gustation

Front 31

1) no taste buds; sense texture

2) only 7-12 total taste buds but about 250 taste buds each

Back 31

1) filiform papillae

2) vallate papillae

Front 32

-stem cells that multiply and replace taste cells that have died
-replace taste buds every 7-10 days

Back 32

basal cells

Front 33

-about 4,000 of them
-mainly on tongue but also inside the cheeks and on the soft palate, pharynx, and epiglottis

Back 33

taste buds

Front 34

-epithelial cell
-have a tuft of apical microvilli called taste hairs
-synapse with sensory nerve fibers at their base and have synaptic vesicles for the release of NT's
-lives only 7-10 days

Back 34

taste cells

Front 35

3 nerves that the taste cell innervates when NT released onto sensory nerve fibers

Back 35

1. Facial VII
2. glossopharyngeal IX
3. Vagus X

Front 36

1. anterior 2/3 of tongue

2. posterior 2/3 of tongue

3. palate, pharynx, epiglottis

Back 36

1. Facial VII

2. Glossopharyngeal IX

3. Vagus X

Front 37

5 taste sensations

Back 37

1. salty
2. sweet
3. sour
4. bitter
5. umami

Front 38

1. Na+, K+

2. sugars

3. acids

Back 38

1. Salty

2. Sweet

3. Sour

Front 39

1. alkaloids

2. amino acids; meaty/savory

Back 39

1. Bitter

2. Umami

Front 40

-neuron
-each cell has 1 of of about 350 kinds of chemoreceptors that bind odorant molecules

Back 40

Olefactory Cell

Front 41

-replace olefactory cells every about 60 days

Back 41

basal cells

Front 42

-epithelium
-in the roof of the nasal cavity
-places the olefactory cells close to the brain
-covers superior concha, cribriform plate, and nasal septum of nasal fossa

Back 42

olefactory mucosa

Front 43

1) -reflexes
-"hunger"

2) emotion

3) emotion

Back 43

1. hypothalamus

2. amygdala

3. hippocampus