Human Sensory Physiology

Question 1

stimulus

Answer 1

something that triggers a reaction in organ or tissue

Question 2

modality

Answer 2

nature of type of stimulus (light, sound), indicated by type of sensory neuron activated

Question 3

quality

Answer 3

differences in modality (diff freq. of sound, sweet and sour taste)

Question 4

intensity

Answer 4

number of receptors activated, frequency of action potentials generated

Question 5

duration

Answer 5

coded by pattern of action potential generation. some neurons generate action potentials for duration of stimulus, some generated ap at on-offset of stimulus

Question 6

location

Answer 6

which group of neurons is active, ear and nose neurons have no location sensor. uses timing to compute location

Question 7

receptor

Answer 7

organ or cell responding to stimuli

Question 8

characteristics of stimulus

Answer 8

modality, intensity, duration, location

Question 9

characteristics of receptors

Answer 9

sensitivity, threshold, density

Question 10

sensitivity

Answer 10

varies with type of receptor

Question 11

5 main types of receptors

Answer 11

chemoreceptor-respond to chemical ligans binding to receptor
mechnaoreceptors- mechnical energy-vibration, sound, pressure
thermoreceptors-temp
electromagnetic receptors- electromagnetic energy, eg light
nociceptors-noxious stimuli (tissue damage interpreted as pain)

Question 12

threshold

Answer 12

min stimulus strength that receptor responds, depends on circumstances

Question 13

density

Answer 13

how many receptors in a given area

Question 14

non-neural receptors

Answer 14

lens, cornea of eye, hairs on arm, tastebuds

Question 15

sensory pathway characteristics

Answer 15

receptive field, specificity of the pathway

Question 16

receptive fields

Answer 16

all the sensory receptors that influence neuron’s activity

Question 17

specificity of the pathway

Answer 17

intensity of stimulus, duration are coded in pattern of action potentials reaching cns
stimulus location and modality coded according to receptors that are activated or timing of activation
each pathway projected to region of cerebral cortex dedicated to a particular receptive field

Question 18

other factors influencing the integration of info and perception

Answer 18

alertness, muscle fatigue, age, experience, adaptation and habituation