Sensory Perception

Question 1

What visual cues allow humans to perceptually organize information?

Answer 1

Depth, form, motion, and constancy

Question 2

How can humans sense the depth of an object?

Answer 2

Binocular cues give people a sense of depth

Retinal disparity: the distance between the two eyes gives a slightly difference image projected onto each retina

Convergence: the degree to which the eyes are turned gives humans a sense of how far away something is

Question 3

How can humans sense the form of an object?

Answer 3

Monocular cues give people a sense of form

These cues allow people to determine the relative size and height of an object, interposition (overlap) of two objects, and shading/contour of an object

Question 4

How can humans sense motion?

Answer 4

Monocular cues give people a sense of motion

Question 5

Motion parallax

Answer 5

Objects that are further away appear to move slower, while those that are closer appear to move faster

Question 6

What is constancy and how to humans sense it?

Answer 6

Constancy is refers to how the perception of an object’s size, shape, and color does not change even if the image projected on the retina changes

Monocular cues give people a sense of constancy

Question 7

What is sensory adaptation and what are some ways that our senses adapt over time?

Answer 7

Sensory adaptation is the ability of our senses to change their sensitivity to stimuli

The eyes adjust to bright stimuli by constricting the pupils and desensitizing the rods and cones. Temperature receptors become less sensitive to cold over time. The inner ear muscle contracts due to loud noises

Question 8

Weber’s Law

Answer 8

The threshold at which you can notice a change in a sensation is the just noticeable difference (JND), also called the difference threshold

ΔI= IK

ΔI= JND

I= initial intensity

As the initial intensity increases, the JND increases (directly proportional)

Question 9

Absolute Threshold of Sensation

Answer 9

Minimum intensity of stimulus required for a subject to reliably detect the stimulus 50% of the time

Many psychological factors influence absolute threshold (motivations, expectations, alertness)

Question 10

Subliminal stimuli

Answer 10

Those that are below the absolute threshold of sensation

Question 11

What are the four types of somatosensation?

Answer 11

1. Proprioception: position
2. Thermoception: temperature
3. Mechanoception: pressure
4. Nociception: pain

Question 12

How is the intensity of a stimulus coded for?

Answer 12

The rate of firing of action potentials

Question 13

What are the three ways a neuron can encode the timing of a stimulus?

Answer 13

1. Nonadapting: the neuron fires at a consistent rate
2. Slow adapting: the neuron fires quickly a the begininning of a stimulus then slows down
3. Fast adapting: the neuron fires quickly at first then stops, then fires again

Question 14

How is the location of a stimulus coded for?

Answer 14

Location-specific stimuli are sent by nerves to the brain, relies on dermatomes

Question 15

What is the vestibular system and what organs are involved?

Answer 15

The vestibular system is a sensory system controlling balance and spatial orientation

It is controlled by the semicircular canals of the inner ear, which detect rotation, and the otolithic organs which detect linear acceleration

Question 17

Signal Detection Theory

Answer 17

Looks at how people make decisions under conditions of uncertainty

Question 18

d’ strength

Answer 18

When a stimulus is strong, people will make more hits than misses

When a stimulus is weak, people will make more misses than hits

Question 19

c: strategy

Answer 19

2 types of signal detection strategies:

1. Conservative: always say no unless 100% sure the signal is present
2. Liberal: always say yes, even if it gets false alarms

Question 21

Bottom up processing

Answer 21

Begins with the stimulus, which influences what we perceive.

This is inductive reasoning and is always correct

Question 22

Top down processing

Answer 22

Background knowledge influences what we perceive

This is deductive reasoning and is influenced by our expectations

Question 23

Gestalt principles

Answer 23

Set of theories that explain why we perceive things the way that we do

Question 25

Law of Similarity

Answer 25

Things that are similar to one another are grouped together by the brain

Question 26

Law of Pragnanz

Answer 26

Reality is reduced to the simplest form

Question 27

Law of proximity

Answer 27

Objects that are close to one another are grouped together

Question 28

Law of continuity

Answer 28

Lines are seen as following the smoothest patj

Question 29

Law of Closure

Answer 29

Objects close together are seen as a whole, the mind fills in the missing information

Question 31

Law of symmetry

Answer 31

the mind perceives objects as being symmetrical and forming around a center point.