Exam 2 - Sensation and Perception

Question 1

Sensation

Answer 1

The simple stimulation of a sense organ

Question 2

Perception

Answer 2

occurs in CNS organizes, identifies, and interprets sensation to form mental representation

Question 3

Transduction

Answer 3

Process in which body converts physical signals (sensations) into neural activities via the CNS (transition state from sensation to perception)

Question 4

Transduction w/ sight

Answer 4

light reflected of surfaces provide eyes with info about the shape, colour, and position of objects

Question 5

Transduction w/ sound

Answer 5

vibrations causes changes in air pressure that travel through space (in the form of a wave) that is registered by the eardrum

Question 6

Transduction w/ touch

Answer 6

Pressure of a surface against the skin signals shape, texture, vibration, pattern & temperature

Question 7

Transduction w/ Taste and Smell

Answer 7

Molecules dispersed in the air or dissolved in saliva real ID of substances that we may or may not want to eat.

Question 8

Psychophysics

Answer 8

methods that measure strength of stimulus and the observer’s sensitivity to that stimulus by reporting whether they felt the stimulus or not

Question 9

Dr. Gustav Fechner

Answer 9

1801-1887

Inventor of psychopysics

Question 10

Absolute threshold

Answer 10

The minimal intensity needed to just barely detect a stimulus 50% of the time

Transition between detecting and not detecting sound is gradual rather than abrupt

Question 11

Absolute threshold of vision

Answer 11

candle flame 50 km away on clear, dark night

Question 12

Absolute threshold of hearing

Answer 12

clock tick 6 meters away when everything is quiet

Question 13

Absolute threshold of touch

Answer 13

fly’s wing falling on cheek from 1 cm away

Question 14

Absolute threshold of smell

Answer 14

single drop of perfume diffused through area equivalent to 6 rooms

Question 15

Absolute threshold of taste

Answer 15

5 mg of sugar dissolved in 7.5 L of water

Question 16

Just noticeable difference (JND)

Answer 16

minimal change in a stimulus that can just barely be detected *not a fixed quantity

Question 17

Weber’s Law

Answer 17

The just noticeable difference of a stimulus is a constant proportion despite variation in intensity

Question 18

Signal Detection theory

Answer 18

The detection of a stimulus depends both the intensity of the stimulus and the physical/psychological state of the individual

Used to measure the way we make decisions under conditions of uncertainty

Question 19

Touch (Somatosenses)

Answer 19

Sensory receptors in our muscles, tendons, joints, and varieity of receptors in our skin allow us to percieve the world through touch

Question 20

How do we sense touch?

Answer 20

transduction of skin sensations to neural signals

Note that some areas of the body discriminate fine spatial detail more effectively than others (think of the homoncolus)

Question 21

Connection of touch to psychology?

Answer 21

Touch is more than just the perception of the sensation; it is also influenced by who or what we percieve to be touching us (this influences our reaction)

(recall the ticklish example)

Question 22

Pain

Answer 22

“An unplasent sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage”

Question 23

Why is pain important?

Answer 23

Essential for survival, as it tells you what is wrong

Changes your behaviour

serves as contrast to pleasurable stimuli

Absence of pain (ex. Congenital insensitivity to pain) is not good, as one cannot tell if you injured yourself

Question 24

Relationship between pain and psychology?

Answer 24

Pain is influenced by psychological and social processes

Often of great concern to people, as it usually means you should see a doctor

Question 25

Visual Acuity

Answer 25

The ability to see fine detail

Question 26

Snellen Chart

Answer 26

Chart used to measure visual acuity

Question 27

Sensing light

Answer 27

Visual system transduces visible light into neural signals in brain

Question 28

Properties of Light Wave

Answer 28

Question 29

Pupil

Answer 29

Circular hole where light enters the eye

Question 30

Iris

Answer 30

Doughnut-shaped coloured area that contains muscles that control the pupil

Question 31

Sclera

Answer 31

The white, outer surface of eye

Question 32

Cornea

Answer 32

Curved, transparent layer covering iris & pupil

Function: Bends incoming light to focus the incoming visual image at the back of the eye

Question 33

Lens

Answer 33

Also bends light, but is adjustable in curvature (controlled by cilliary body; extra info) and allows fine-tuning of curvature

Question 34

Accomodation

Answer 34