Unit 1: Intro To Perception

Question 1

What does Plato’s allegory of the cave say about our perception?

Answer 1

Our perception is limited to our experiences

Question 2

Adaption

Answer 2

a reduction in response (reduction in perception) caused by prior continuing stimulation

Question 3

Perceptual priming

Answer 3

change (improvement) in perception due to exposure to a previous stimulus

Question 4

Democritus

Answer 4

Sensations are caused by atoms leaving objects and making contact with our sense organs

Question 5

Sensory transducer

Answer 5

a receptor that converts physical energy from the environment into neural activity

Question 6

Nativism

Answer 6

the idea that the mind produces ideas that are not derived from external sources

Question 7

Mind-body dualism

Answer 7

existence of two distinct principles of being in the universe: spirit/soul and matter/body. Mind and body are two separate entities

Question 8

Monism

Answer 8

the idea that the mind and matter are formed from, or reducible to a single ultimate substance or principle of being

Question 9

Idealism

Answer 9

the idea that reality is indistinguishable and inseparable from human perception and understanding; that reality is a mental construct closely related connected to ideas

Question 10

Materialism

Answer 10

the idea that physical matter is the only reality, and everything including the mind can be explained in terms of matter and physical phenomena

Question 11

Empiricism

Answer 11

experience from the senses is the only source of knowledge

Question 12

Who is the founder of experimental psychology?

Answer 12

Fechner

Question 13

Panpsychism

Answer 13

all matter has consciousness

Question 14

Psychophysics

Answer 14

the science of defining qualitative relationships between the physical and psychological (subjective) events. If consciousness is a property of matter, then we can measure it and set laws!

Question 15

Webers law

Answer 15

JND is a constant proportion of the stimulus intensity level

Question 16

Just noticeable difference

Answer 16

the smallest detectable difference between two stimuli, or the minimum change in a stimulus that can be correctly judged as different from a reference stimulus. AKA: difference threshold
- change in intensity leads to change in sensation

Question 17

Fechner’s Law

Answer 17

S=klogI. S = psychological sensation; I = intensity; k = constant

Question 18

Absolute threshold

Answer 18

minimum amount of stimulation necessary for a person to detect a stimulus 50% of the time

Question 19

5 psychophysical methods:

Answer 19

method of constant stimuli
- Method of limits
- Method of adjustment
- Method of estimation
- Cross modality matching

Question 20

Method of constant stimuli

Answer 20

many stim ranging from rarely to almost always perceivable are presented one at a time. Participants response yes/no

Question 21

Method of limits

Answer 21

particular dimension of a stim, or the differences between two stim is varied incrementally until the participant responds differently

Question 22

Method of adjustment

Answer 22

like the method of limits but the participant is controlling the intensity of the stimulus.

Question 23

Magnitude estimation

Answer 23

participants assigns values according to perceived magnitudes of the stimuli
- on a scale of one to 10 or rank these based on…

Question 24

Steven’s Power Law

Answer 24

S =al^b
S = sens; a = constant; I= intensity; b = exponent
* Length have exponent of 1; pain has high exponent

Question 25

Cross modality matching

Answer 25

the ability to match the intensities of sensations that come from different sensory modalities. Adjusting brightness of light to the loudness of a tone

Question 26

Signal detection theory

Answer 26

quantifies the response of an observer to the presentation of a signal in the presence of a noise (randomness of perception)
- hit, miss, false alarm, correct rejection

Question 27

Sensitivity (d’)

Answer 27

signal to noise ratio; either internal or external noise = z hit - z false alarm
- perfect sensitivity = infinite
- Cannot do task = 0

Question 28

Signal detection theory considerations (2)

Answer 28

Doesn’t measure the factors
- participant with either high/low sensitivity
- Or the task is too easy/difficult
Biases: Unbiased vs biased observer
- Cost of decisions
- Probability of events (expecting phone calls)
- Personality(Liberal/risk-taking vs conservative)

Question 29

Biology and perception

Answer 29

Perception and senses are a product of natural evolution. importance of type of energy in the environment determines which senses developed

Question 30

Neuroimaging

Answer 30

Methods that generate images of the structure and/or function of the brain.

Question 31

Electroencephalography (EEG):

Answer 31

measures electrical activity through dozens of electrodes placed on the scalp

DOES NOT ALLOW to learn what individual neurons are doing/ pinpoint area of neural activity
DOES roughly localize whole populations of neurons and to measure their activities with excellent temporal accuracy
You have to average the activity across multiple trials event-related potential (ERP)

Question 32

Magnetoencephalography (MEG)

Answer 32

measures changes in magnetic activity across populations of many neurons in the brain
Where in the brain is most active
EEG is simple and cheap; MEG is expensive

Question 33

Magnetic Resonance Imaging (MRI)

Answer 33

uses responses of atoms to strong magnetic fields to form images of structures like the brain,
Looks for hydrogen

Question 34

Functional Magnetic Resonance Imaging (fMRI)

Answer 34

Functional Magnetic Resonance Imaging (fMRI): possible to measure localized patterns of activity in the brain
Activated neurons provoke increased blood flow which can be quantified by measuring changes in the response of oxygenated and deoxygenated blood to strong magnetic fields
Looks for oxygen
They are noisy and expensive

Question 35

Positron Emission Tomography (PET)

Answer 35

enables us to define locations in the brain where neurons are especially active by measuring the metabolism of brain cells using safe radioactive isotopes
Tracer is introduced into the bloodstream, and a specialized camera detects gamma rays emitted