Sensation And Perception Unit 1

Front 1

Sensation

Back 1

the chain of biochemical and neurological events that begins with the impinging of a stimulus upon the receptor cells of a sensory organ.

Front 2

perception

Back 2

the mental state that entails symbolic representation of the external world

Front 3

qualia

Back 3

basic perceptual symbols such as 'red', 'hot', 'smooth', 'loud'.

Front 4

the law of specific nerve energies

Back 4

this term expresses the fact that we are aware only of the activity of our nervous systems. For this reason, what matters is which nerves are stimulated, not how they are stimulated.

Front 5

mind-body problem

Back 5

the nature of perception

Front 6

dualism

Back 6

idea that mental states are non-physical substances interacting with the physical brain

Front 7

materialism

Back 7

idea that mental states are physical, emerging from the brain activity as a whole.

Front 8

Finding neural correlates of perception is hard, but...

Back 8

...understanding why we need perception at all is even harder,

Front 9

the two basic schemes of information processing

Back 9

the basic schemes of <this> are bottom up and top down (knowledge based)

Front 10

All the senses (9)

Back 10

sight, hearing, touch, taste, smell, temperature, pain, balance, body sense

Front 11

sensory receptor

Back 11

a structure that recognizes a stimulus in the internal or external environment of an organism

Front 12

sensory transduction

Back 12

initiated by sensory receptor in response to stimuli, creates action potentials in the same cell or an adjacent one

Front 13

G protein-coupled receptors

Back 13

a family or protein receptors that transduce and extracellular signal into an intracellular signal by means of G protein activation

Front 14

neuron

Back 14

main cells in the nervous system, they process and transmit information

Front 15

soma

Back 15

cell body of a neuron

Front 16

axon

Back 16

transport output lane of a neuron

Front 17

denritic tree (dendrites)

Back 17

where a neuron receives inputs

Front 18

action potential

Back 18

electrical signal spike generated and propagated by neurons

Front 19

graded potential

Back 19

smooth sloped electric signal generated by neurons

Front 20

nerve impulses

Back 20

electrochemical; voltages change along axon as electrically charged ions (sodium and potassium) pass in and out of the membranes of nerve cells

Front 21

neurotransmitters

Back 21

molecules that cross the synapse from the axon of one neuron to the dendrite of the next.

Front 22

human brain

Back 22

main part of central nervous system, controls lower (heart) and higher (thought) activities.

Front 23

cerebrum

Back 23

contains cerebral cortex, lots of the forebrain. Does movement, sensory processing, learning, memory, language.

Front 24

cerebral cortex

Back 24

outermost layer of cerebral cortex, contains sensory processing area (among others)

Front 25

cerebellum

Back 25

small circle brain thing in the back, mostly motor control

Front 26

thalamus

Back 26

relays sensation, spatial sense, and motor signals to cerebral cortext

Front 27

brain stem

Back 27

all information going to brain passes through brain stem. contains sensation carrying pathways.

Front 28

corpos callosum

Back 28

connects the two brain cortexes

Front 29

gray matter

Back 29

neurons (10%) and supporting glia cells (90%)

Front 30

white matter

Back 30

neuronal projections (axons) which interconnect neurons

Front 31

cranial nerves

Back 31

12 pairs of paths(left &right) which transmit sensory information

Front 32

PET

Back 32

positron emission tomography

Front 33

MRI

Back 33

functional magnetic resonance imaging

Front 34

EEG/MEG

Back 34

elelectro/magnetic encephalogram

Front 35

Fechner

Back 35

founder of psychophysics. discovered relationship of psychological sensation and the physical intensity of a stimulus via the formula: "S = K Log I". also developed threshold measurements, reaction time measurements, and magnitude estimation

Front 36

threshold measurement

Back 36

measuring the minimum detectable stimulus change.

Front 37

magnitude estimation

Back 37

people are asked to assign numbers in proportion to the magnitude of the stimulus

Front 38

somatosensory system

Back 38

the neural system connected to skin receptors that senses touch, temperature, pain, proprioception

Front 39

Meissner Corpuscle

Back 39

transient local stimulation

Front 40

Pacinian corpuscle

Back 40

transient global stimulation

Front 41

merkel disks

Back 41

sense steady pressure of a small object

Front 42

ruffini endings

Back 42

sense steady pressure and stretching

Front 43

somatosensory cortex

Back 43

receives different signals from receptors via nerves (different nerves for different receptors). Located in parietal lobe

Hands, face, and lips have the most material dedicated to them in the somato-cortex

Front 44

homunculus

Back 44

little representation of human (can be used to demonstrate how much of the brain is dedicated to sensing stimuli on different areas)

Front 45

receptive field

Back 45

the area of skin that excites a touch receptor.Neurons in the somatosensory cortex have center-surround receptive fields: excitatory center, inhibitory surround, or vice versa.

Front 46

vibrotactile stimulation

Back 46

measures sensitivity for touch, which is highest for lips, and lowest for soles of feet

Front 47

touch spacial acuity

Back 47

can be measured by two point threshold test(highest for index fingers, lowest for calves)

Front 48

phantom limb pain

Back 48

50-80% of amputees suffer from it, which demonstrates the perceptual nature of touch. Explained by an incomplete cortical reorganization following amputation

Front 49

anticipatory inhibition mechanism

Back 49

explains how we distinguish events in the environment from self-induced events. tickling sensation occurs when the touch simulation was not anticipated

Front 50

olfaction

Back 50

smelling, one of the two chemical senses (other is tatste)

Front 51

olfactory epithelium

Back 51

specialized tissue inside nasal cavity containing 10 million olfactory sensory neurons

Front 52

olfactory sensory neuron

Back 52

cell inside nose regenerated every 40 days from basal stem cells. Contain olfactory receptors. Sends signal to olfactory bulb

Front 53

olfactory receptor

Back 53

g protein-coupled receptor, there are as many as a 1000 different olfactory receptors.

Front 54

theories of olfaction:

Back 54

molecular shape theory: (lock and key)
molecular vibrations theory: vibration of an oderant determines smell

Front 55

olfactory bulb

Back 55

receives signal from OSN (olfactory sensory neuron). Enhances sensitivity and discrimination of odor detection. Projects to olfactory cortex.

Front 56

distributed coding (olfaction)

Back 56

belief that neurons in the olfactory cortex identify odors as activity patterns distributed across many OSNs.

Front 57

olfactory sensitivity

Back 57

varies from odor to odor, some are easily discriminated, others are hard to recognize even if they are familiar odors.

Front 58

odors become associated with...

Back 58

...events and can serve as potent memory cues. They also affect emotional state.

Front 59

familiar odors also seem more...

Back 59

...pleasant. Pleasant odors seem more familiar.

Front 60

n cordon

Back 60

A cordon is a line or ring of police, soldiers, or vehicles preventing people from entering or leaving an area.
Police formed a cordon between the two crowds.

Front 61

the last line of defense for preventing unwanted chemicals from entering the body.

Back 61

taste

Front 62

papillae

Back 62

bumpy structures on tongue

Front 63

taste buds

Back 63

found on the papillae and roof of the mouth which contain taste receptor cells.

Front 64

fungiform papillae

Back 64

front of the tongue

Front 65

foliate papillae

Back 65

rear edges of the tongue

Front 66

circumvallate papillae

Back 66

rear center of the tongue

Front 67

supertaster

Back 67

person with more than normal number of fungiform papillae, very sensitive to bitter foods.

Front 68

taste receptor cell

Back 68

contains microvilli studded with taste receptors, supporting cells, and basal stem cells, which regenerate every 10 days.

Front 69

where do taste signals go?

Back 69

ipsilateral (no crossover) - brainstem, thalamas, gustatory cortex

Front 70

what taste are humans most sensitive to?

Back 70

bitter (poisons are bitter)

Front 71

emotional response to taste is wired...

Back 71

at a subcortical level (low level)

Front 72

adaptation

Back 72

pleasure reversal effect occurs.

in tasting, sweet/salty foods create a sour/bitter aftertaste.