Chapter 5

Question 1

Sensation

Answer 1

the stimulus detection process by which our sense organs respond to and translate environmental stimuli into nerve impulses that are sent to the brain.

Question 2

Perception

Answer 2

making “sense” of what our senses tell us; it is the active process of organizign this stimulus input and giving in meaning.

Question 3

Sensory transduction

Answer 3

the process whereby the characteristics of a stimulus are converted into nerve impulses.

Question 4

Psychophysics

Answer 4

studies the relationship between the physical characteristics of stimuli and sensory capabilities.

Question 5

Decision criterion

Answer 5

how certain someone must be that a stimulus is present before they will say they can detect it

Question 6

Signal Detection Theory

Answer 6

an account of sensory perception that is concerned with the factors that influence humans judgements about sensory stimuli.

Question 7

Difference threshold

Answer 7

defined as the smallest difference between two stimuli that someone of some people can perceive 50% of the time. This is the same as Just Noticeable difference (JND)

Question 8

Sensory Adaption

Answer 8

The diminishing sensitivity to an unchanging stimulus.

Question 9

Sensory Transduction

Answer 9

the process whereby the characteristics of a stimulus are converted into nerve impulses

Question 10

Lens

Answer 10

an elastic structure in the eye that becomes thinner to focus on distant objects and thicker to focus on nearby objects.

Question 11

Retina

Answer 11

multilayered light-sensitive tissue at the rear of the fluid-filled eyeball.

Question 12

Rods (receptor)

Answer 12

function best in dim light, and are primarily black-and-white brightness receptors.

Question 13

Cones (receptor)

Answer 13

Colour receptor, which function best in bright illumination.

Question 14

Fovea

Answer 14

Small area in the centre of the retina that contains no rods, but many densely packed cones.

Question 15

Optic Nerve

Answer 15

Ganglion cells, whose axons are collected into a bundle to form the optic nerve

Question 16

Visual Acuity

Answer 16

ability to see fine detail

Question 17

Photo Pigments

Answer 17

rods and cones translate light waves into nerve impulses through the action of protein molecules called photo-pigments

Question 18

Dark Adaption

Answer 18

the progressive improvement in brightness that occurs over time under conditions of low illumination

Question 19

Young-Helmholtz trichromatic theory

Answer 19

states that there are three types of colour receptors in the retina

Question 20

Hearings opponent process theory

Answer 20

states that each of the three cone types respond to two different wavelength.

Question 21

Dual-process theory

Answer 21

combines the trichromatic and opponent process theories to account for the colour transduction process.

Question 22

Feature detectors

Answer 22

fire selectively in response to visual stimuli that have specific characteristics

(Neurons)

Question 23

Frequency

Answer 23

the number of sound waves, or cycles, per second.

Question 24

Hertz (Hz)

Answer 24

the measure of cycles per second: 1 Hz = 1 cycle per second

Question 25

Amplitude

Answer 25

the vertical size of the sound waves – the depth between the peaks and the troughs in the sound wave.

Question 26

Decibel (dB)

Answer 26

measure of the physical pressure that occur at the eardrum

Question 27

Cochlea

Question 28

Hyperopia

Answer 28

Farsightedness

Question 29

Myopia

Answer 29

Nearsightedness

Question 30

Visual process

Answer 30

Cornea -> pupil (iris) -> Lens (ciliary muscles) -> Retina (rods, cons, fovea) -> Rods&Cons to bipolar cells (fotopigment) -> ganglion cells -> Synsnerven -> Thalamus -> Visual Cortex

Question 31

Absolute threshold

Answer 31

the lowest intensity at which a stimulus can be detected 50 percent of the time.

Question 32

Manipulation

Answer 32

Increasing the rewards for hit or the costs for misses results in lower detection thresholds.(absolute threshold)

Question 33

Webers Law

Answer 33

states that the difference threshold, or JND, is directly proportional to the magnitude of the stimulus with which the comparison is being made.The needed for change is referred to as Webers fraction

Question 34

Two particular kinds of visual adaption

Answer 34

Light adaption & Dark adaption

Question 35

Light

Answer 35

waves of electromagnetic radiation (or energy).

Question 36

How to measure light

Answer 36

waves of electromagnetic radiation measured in nanometers (nm).

Question 37

Electromagnetic spectrum

Answer 37

We can see a tiny portion. Also includes: X-rays, television, radio signals, infrared and ultraviolet .

Radio station analogy. Theres a lot of sound, but we can only listen to the specific places it hits a station.