Sensation vs Perception 2.1

Question 1

How does sensation start ?

Answer 1

raw signal & unprocessed till enters CNS

Question 2

What is perception?

Answer 2

processing this information within the central nervous system in order to make sense of the information’s
significance.

Question 3

Distal vs Proximal stimuli?

Answer 3

Physical objects outside of the body (Distal stimulus) (directly interact/affect sensory receptors) and produce proximal stimuli like photons, sound waves, heat, pressure, they directly interact with sensory receptors

*Study of this is psychophysics

Question 4

What’re Ganglia?

Answer 4

• collections of neuron cell bodies found outside the CNS
• Transmitted through sensory ganglia

Question 5

What’re Photoreceptors?

Answer 5

Respond to EM waves in the visible spectrum (sight)

Question 6

What’re Mechanoreceptors?

Answer 6

respond to pressure or movement

Question 7

What’re Nociceptors?

Answer 7

respond to painful or noxious stimuli

Question 8

What’re Osmoreceptors?

Answer 8

respond to the osmolarity of the blood

Question 9

Absolute Threshold

Answer 9

• minimum of stimulus energy that is needed to activate a sensory system (converted to action potentials)
• how bright, loud, or intense a stimulus must be before it is sensed.

Question 10

What causes lack of conscious perception?

Answer 10

the stimulus is too subtle to demand our attention, or may last for too brief a duration for the brain to fully process
the information

Question 11

What’s threshold of conscious
perception?

Answer 11

level of intensity that a stimulus must pass in order to be consciously perceived by the brain

Question 12

What’s subliminal perception?

Answer 12

• Information that’s received by the CNS but doesn’t cross threshold
• arrives at CNS, but doesn’t reach the higher-order brain regions that control attention and consciousness

Question 13

What’s difference threshold?

Answer 13

• minimum change in magnitude required for an observer to perceive that two different stimuli are, in fact, different
• If below threshold then will be the same

Question 14

What’s discrimination testing?

Answer 14

The stimulus is then varied slightly and researchers ask the participant to report whether they perceive a change

Question 15

What is Weber’s Law?

Answer 15

• the observation that difference thresholds are proportional and must be computed as percentages
• (New - Original) Difference/ Original

Question 16

What’s Signal detection theory?

Answer 16

studies how internal (psychological) and external (environmental) factors influence thresholds of sensation and perception

Question 17

How do signal detection experiments work?

Answer 17

Noise Trials - Trials in which the
signal is presented
Catch Trials - the signal
is not presented
Hit - trial in which the signal is presented and the subject correctly perceives the signal
Miss - trial in which the subject fails to perceive the presented signal
False Alarm - trial in which the subject indicates perceiving the signal,
even though the signal was not presented
Correct Negative - trial in
which the subject correctly identifies that no signal was presented