Chapter 1

Question 1

Perceptron

Answer 1

• Created by pschologist Frank Rosenblatt (1958)
• A room-sized, five-ton computer that could teach itself to distinguish between basic images, like cards with writings on the left. vs right side.
• it took 50 trials to learn this simple task, and it was unable to carry out more complex tasks
• it’s a precursor to modern AI

Question 2

Computers as perceivers today

Answer 2

• computers still can’t perceive as well as humans
• if a computer has never seen a toothbrush, it identifies it as something with a similar shape

Question 3

Perception

Answer 3

Conscious sensory experience, it is done very easily. It is identified with complex processes that involve higher-order mechanisms such as interpretation and memory that involve activity in the brain

Question 4

Is perception direct?

Answer 4

We don’t only perceive what is in our environment as it is. Everything we perceive is the result of the activity in your nervous system and your knowledge gained from past experience. Perception depends on the properties of your body, such as your sensory receptors and brain.

Question 5

Sensation

Answer 5

Often identified as involving simple “elementary” processes that occur right at the beginning of a sensory system.

Question 6

Is sensation vs. perception an important distinction?

Answer 6

Even a simple stimulus can be interpreted in different ways: calling some processes sensation and others perception doesn’t add anything to our understanding of how our sensory experiences are created. Recent research tends to argue that everything that involves understanding how we experience the world through our senses comes under the heading of perception.

Question 7

The perceptual process

Answer 7

A sequence of 7 steps leading from the environment to perception of a stimulus, and action with regard to the stimulus. Steps in the perceptual process do not always unfold in a one-follows-the-other order (it can turn into a cycle in which the action taken can change the person’s perception of the stimulus).

Question 8

Steps of the perceptual process

Answer 8

• Stimulus in the environment
• Stimulus hits receptor
• Receptor processes
• Neural processing
• Perception
• Recognition
• Action

Question 9

Distal stimuli

Answer 9

The stimuli coming from the external environment

Question 10

Proximal stimuli

Answer 10

The stimuli on the receptors (ex. the image on the retina for vision).

Question 11

Principle of transformation

Answer 11

Stimuli and responses created by stimuli are transformed, or changed, between the distal stimulus and perception. The distal stimulus is transformed into the proximal stimulus.

Question 12

Principle of representation

Answer 12

Everything a person perceives is based not on direct contact with stimuli but on representations of stimuli that are formed on the receptors and the resulting activity in the person’s nervous system. The proximal stimulus represents the distal stimulus in the person’s mind/receptor.

Question 13

Sensory receptors

Answer 13

Cells specialized to respond to environmental energy, with each sensory system’s receptors specialized to respond to a specific type of energy. They act as bridges between the external sensory world and the internal (neural) representation of that world.

Question 14

Sensory receptor actions

Answer 14

(1) They transform environmental energy into electrical energy;
(2) They shape perception by the way they respond to different properties of the stimuli.

Question 15

Transduction

Answer 15

In the senses, the transformation of environmental energy into electrical energy. For example, the retinal receptors transduce light energy into electrical energy.

Question 16

Functions of neurons

Answer 16

1) transmit signals from the receptors to the brain and then within the brain
(2) change (or process) these signals as they are transmitted. These changes occur because of itneractions between neurons as the signals travel from the receptors to the brain. Some signals are reduced and others are amplified.

Question 17

Neural processing

Answer 17

Operations that transform electrical signals within a network of neurons or that transform the response of individual neurons.

Question 18

Primary receiving area

Answer 18

Area of the cerebral cortex that first receives most of the signals initiated by a sense’s receptors. For example, the occipital cortex is the site of the primary receiving area for vision, and the temporal lobe is the site of the primary receiving area for hearing.

Question 19

Cerebral cortex

Answer 19

The 2-mm-thick layer that covers the surface of the brain and contains the machinery for creating perception, as well as for other functions, such as language, memory, and thinking.

Question 20

Occipital lobe

Answer 20

Lobe at the back of the cortex that is the site of the cortical receiving area for vision.

Question 21

Temporal lobe

Answer 21

A lobe on the side of the cortex that is the site of the cortical receiving area for hearing and the termination point for the ventral, or what, stream for visual processing. A number of areas in the temporal lobe, such as the fusiform face area and the extrastriate body area, serve functions related to perceiving and recognizing objects.

Question 22

Parietal lobe

Answer 22

A lobe at the top of the cortex that is the site of the cortical receiving area for touch and is the termination point of the dorsal (where or how) stream for visual processing.

Question 23

Frontal lobe

Answer 23

Receiving signals from all of the senses, the frontal lobe plays an important role in perceptions that involve the coordination of information received through two or more senses. It also serves functions such as language, thought, memory, and motor functioning.

Question 24

Recognition

Answer 24

The ability to place an object in a category that gives it meaning—for example, recognizing a particular red object as a tomato.

Question 25

Visual object agnosia

Answer 25

The inability to recognize objects. It isn’t due to an eye problem, but a brain one (like a brain tumor). For example, the patient could perceive parts of objects but can’t identify the whole object

Question 26

Action

Answer 26

• Motor activity in response to a stimulus
• Step 7 of the perceptual process
• It is an important outcome of the perceptual process because of its importance for survival (evolutionarily, the major goal of visual processing was not to create a conscious perception or “picture” of the environment but to help the animal control navigation, catch prey, detec predators, etc.)

Question 27

Knowledge

Answer 27

Any information that the perceiver brings to a situation, like prior experiences (either recent or ancient), or expectations. Knowledge can influence our ability to categorize.

Question 28

The rat-man demonstration

Answer 28

The demonstration in which presentation of a “ratlike” or “manlike” picture influences an observer’s perception of a second picture, which can be interpreted either as a rat or as a man. This demonstration illustrates an effect of top-down processing on perception.

Question 29

Bottom-up processing

Answer 29

Processing that is based on the information on the receptors. Also called data-based processing.

Question 30

Top-down processing

Answer 30

Processing that starts with the analysis of high-level information, such as the knowledge a person brings to a situation. Also called knowledge-based processing. It is often used: the more complex the stimulus, the more needed top-down processing is.

Question 31

The 3 major components of the perceptual process

Answer 31

• Stimulus (distal and proximal; Steps 1–2)
• Physiology (receptors and neural processing; Steps 3–4)
• Behavior (perception, recognition, action; Steps 5–7)
  The goal of perceptual research is to understand the relationships between these 3 components. Each one of the 3 relationships provides information about different aspects of the perceptual process.

Question 32

Oblique effect

Answer 32

Enhanced sensitivity to vertically and horizontally oriented visual stimuli compared to obliquely oriented (slanted) stimuli. This effect has been demonstrated by measuring both perception and neural responding.

Question 33

Stimulus–behavior relationship

Answer 33

The relationship between stimuli and behavioral responses, where behavioral responses can be perception, recognition, or action.

Question 34

Psychophysics

Answer 34

Traditionally, the term psychophysics refers to quantitative methods for measuring the relationship between properties of the stimulus and the subject’s experience. In this book, all methods that are used to determine the relationship between stimuli and perception will be broadly referred to as psychophysical methods.

Question 35

Grating acuity

Answer 35

The narrowest spacing of a grooved surface on the skin for which orientation can be accurately judged. When grating acuity is assessed at different orientations, the results show that acuity is best for gratings oriented vertically or horizontally, rather than obliquely.

Question 36

Stimulus–physiology relationship

Answer 36

The relationship between stimuli and physiological responses. Often studied by measuring brain activity.

Question 37

Physiology–behavior relationship

Answer 37

Relationship between physiological responses and behavioral responses.

Question 38

Absolute threshold

Answer 38

The smallest stimulus level that can just be detected. In the grating acuity example, this threshold was the smallest line width that can be detected. Thresholds measured the limits (minimums) of sensory systems.

Question 39

Fechner’s influence on psychology

Answer 39

He was a professor of physics that introduced ways of measuring thresholds of human perception. He believed that the mind and body should not be thought of as totally separate from one another but as two sides of a signle reality. He proposed that the mind could be studied by measuring the relationship between changes in physical stimulation and a person’s experience.

Question 40

Classical psychophysical methods

Answer 40

The methods of limits, adjustment, and constant stimuli, described by Fechner, that are used for measuring thresholds. What method to use is determined by the degree of accuracy needed and the amount of time available.

Question 41

Method of limits

Answer 41

The experimenter presents stimuli in either ascending or descending order. The change from being able to perceive it to not being able to is called a crossover point. Because the crossover points may vary slightly, this procedure is repeated a number of times, starting above the threshold half the time and starting below the threshold half the time (the threshold is then determined by calculating the average of the crossover points).

Question 42

Method of constant stimuli

Answer 42

Different stimulus intensities are presented one at a time at random, and the participant must respond whether they perceive it or not on each trial. The threshold is usually defined as the intensity that results in detection on 50 percent of trials. This is the most accurate, but most time-consuming method.

Question 43

Method of adjustment

Answer 43

The participant adjusts the stimulus intensity continuously until they can just barely detect it. This just barely audible intensity is taken as the threshold. The procedure is repeated numerous times, and the threshold is determined by taking the average setting.

Question 44

Difference threshold

Answer 44

The minimum difference that must exist between two stimuli before we can tell the difference between them. They were first measured by physiologist Ernst Weber in the 1800s.

Question 45

Magnitude estimation

Answer 45

A psychophysical method in which the subject assigns numbers to a stimulus that are proportional to the subjective magnitude of the stimulus. The experimenter first presents a “standard” stimulus to the participant and assigns it a value. The participant then hears sounds of different intensities, and is asked to assign a number to each of these sounds that is proportional to the loudness of the original sound. This number for “loudness” is the perceived magnitude of the stimulus.

Question 46

Recognition testing

Answer 46

The recognition ability of people with brain damage is tested by asking them to name objects or pictures of objects. Recognition is also used to assess the perceptual abilities of healthy people (ex. an experiment showed that people can rapidly identify pictures but seeing small details requires more time). Because recognizing objects is so crucial for our survival, many perception researchers have shifted their emphasis from asking “What do you see?” (perception) to asking “What is that called?” (recognition).

Question 47

Reaction time

Answer 47

The time between presentation of a stimulus and an observer’s or listener’s response to the stimulus. Reaction time is often used in experiments as a measure of speed of processing.

Question 48

Phenomenological report

Answer 48

Method of determining the relationship between stimuli and perception in which the observer describes what they perceive. Phenomenological reports are important because they define the perceptual phenomena we want to explain, and once a phenomenon is identified, we can then study it using other methods.

Question 49

Five questions about the perceptual world

Answer 49

• What is the perceptual magnitude of a stimulus?
• What is the identity of the stimulus (recognition)?
• How quickly can I react to it?
• How can I describe what is out there?
• How can I interact with it?

Question 50

Physical vs. perceptual

Answer 50

If changes in physical stimuli always resulted in similar changes in perception of those stimuli … there would be no need for psychology; human perception could be wholly explained by the laws of the discipline of physics. Perceptual responses are not necessarily the same as the responses of physical measuring devices.

Question 51

Electromagnetic spectrum

Answer 51

Continuum of electromagnetic energy that extends from very-short-wavelength gamma rays to long-wavelength radio waves. Visible light is a narrow band within this spectrum.