Exam 1 (Ch 1-3)

Question 1

Overview

Question 2

What is sensation?

Answer 2

The ability to detect a stimulus and turn it into something our brain knows

Question 3

What is perception?

Answer 3

Giving meaning to the sensation

Question 4

What is transduction?

Answer 4

Physical energy –> electrical energy

Question 5

Top-down processing

Answer 5

Perceiving things based on prior experiences and/or knowledge

Question 6

Bottom-up processing

Answer 6

Perceiving things based on sensory stimuli pieced together using data from our senses

Question 7

Methods

Question 8

History

Answer 8

• Fechner and Weber
• Psychology of what was happening
• Psychophysics - science of defining quantitative relations between the physical and psychological

Question 9

Psychophysics

Question 10

Just Noticable Difference

Answer 10

The smallest detectable difference between teo stimuli

Question 11

Absolute Threshold

Answer 11

• The minimum intensity of a stimulis that can be detected 50% of the time
• The second something goes from nothing to something it has crossed your absolute threshold (radio example)

Question 12

Weber’s Law

Answer 12

Describes the relationship between stimulus and resulting sensations - says that the JND is a constant ratio of the original stimulus

Question 13

Fechner’s Law

Answer 13

• Made Weber’s law more universal
• Says that the magnitude of subjective sensation increases proportionally to the logarithm of the stimulus intensity

Question 14

Threshold methods

Question 16

Method of Constant Stimuli

Answer 16

• Hearing test
• a range of stimuli are randomly presented one at a time and participants respond yes/no if they perceive it

Question 17

Method of Limits

Answer 17

• Playing sound at full volume and turning it down until it is no longer heard (vise versa)
• A stimulus is presented and either increased or decreased until the participant perceives it

Question 18

Method of Adjustment

Answer 18

• Same as method of limits but participant controls the change

Question 19

Scaling

Question 20

Magnitiude Estimation

Answer 20

• Doctor pain scale (1-10)
• Asking participants to rate the perceived magnitude of a stimulus

Question 21

Cross-Modality Matching

Answer 21

• Strongest pain, loudest sound, brightest light, brightness of the sun, heat of scalding water scale
• Asking participants to match the intensities of sensations that come from different sensory modalities

Question 22

Signals and Signal Detection Theory

Question 23

Signal Detection Theory

Answer 23

Measures the ability to differentiate between a signal (a stimulus) and surrounding noise
- Hit (it is cancer), miss (miss the cancer), false alarm (say its cancer and its not), correct rejection (not cancer and say its not)

Question 24

Fourier Analysis

Answer 24

A mathematical way of breaking down signals into their respective component sine waves