Chapter 1: Foundations

Question 1

Sensation

Answer 1

initial process of turning physical features/ stimuli into electrochemical signals that are sent to brain to be processed

Question 2

Senses

Answer 2

physiological process of turning environmental stimuli into electrochemical signals

Question 3

Study of perception is highly interdisciplinary

• Psychology
• Physics and Chemistry
• Cognitive neuroscience
• Neuropsychology and neurology
• Computer science and artificial intelligence
• Biomedical engineering
• Philosophy

Answer 3

Study of perception is highly interdisciplinary

• Psychology- perception is aspect of how mind works
• Physics and Chemistry- involved the study of things that can be sensed
• Cognitive neuroscience- study of brain, cognition, and behavior
• Neuropsychology and neurology- study of brain damage and how affects perception
• Computer science and artificial intelligence- building computational devices that can be model perception and response to world
• Biomedical engineering- brain imaging and building sensory prosthetics
• Philosophy- subjective awareness, knowledge, and consciousness

Question 4

Representation

Answer 4

info in brain used to represent objects/ events to store them in memory and to support thoughts and actions

Question 5

Stimuli

Answer 5

objects and events that are perceived (distal) and the phenomena produced (proximal)

Question 6

Perception

Answer 6

initial sensory signals are used to represent objects and events

Question 7

Process of Perception

1.
2.
3.
4.
5.

Answer 7

Process of Perception

1. Distal Stimuli- perceived object/ event
   - whatever physical energy is coming from
   - furthest away from body
2. Proximal Stimuli
   - physical phenomenon evoked by distal stimuli that impinges on specialized cells
   - physical energy
3. Proximal stimuli converted to neural signals, which are sent to brain
   - Sensory Receptors- specialized neurons that convert proximal stimuli to neural signals
4. Signal processing in the brain
5. Conscious awareness

Question 8

Where perception begins:

Answer 8

Transduction: physical signal -> neural signal

Question 9

Neural Code

Answer 9

pattern of neural signals that carry info about stimulus and can be representation

Question 10

Psychophysics

Answer 10

relation between psychological phenomena and physical stimuli

Question 11

Bottom-Up Processing

Answer 11

info contained in neural signals from receptors

Question 12

Top- Down Information

Answer 12

observer’s knowledge, expectations, and goals, which can affect perception

Question 13

Gustav Fechner

Answer 13

• German experimental psychologist

- Published ‘Elements of Psychophysics’

Question 14

Absolute Threshold

Answer 14

minimum intensity of physical stimulus that can be detected by observer

Question 15

Psychometric Function

Answer 15

curve that relates measure of perceptual experience to intensity of physical stimulus

Question 16

Method of Adjustment

Answer 16

participant observes and controls stimulus to change intensity of stimulus

    - can come up with average for individual after many trials
    - ie. dot slider

Question 17

Method of Constant Stimuli

Answer 17

participant is repeatedly given fixed set of stimuli of different intensities and then indicates if stimulus was detected

    - researcher controls stimulus
    - ie. yes, no clicker

Question 18

Staircase Method

Answer 18

participant says whether or not they perceive stimulus and are presented stimulus that is one step higher or lower accordingly

Question 19

Aristotle Illusion

Answer 19

cortical mapping in different area that’s not what was previously experienced, you perceive it differently

Question 20

Difference Threshold/ Just Noticeable Difference (JND)

Answer 20

minimum difference between two stimuli that allows an observer to perceive that two stimuli are different

Question 21

Ernst Weber

Answer 21

carried out a large number of experiments to estimate the JND for different intensities if standard stimuli for different perceptual dimensions

Question 22

Psychophysical Scaling

Answer 22

process of measuring how changes in stimulus intensity relate to changes in the perceived intensity

Question 23

Steven’s Power Equation

Answer 23

S= cI^n

n<1

• response compression
• underestimation
• ie. brightness

n>1

- response expansion
- overestimation
- electric shock

Question 24

Johannes Muller

Answer 24

• Perception based on neural activity
• “Law of specific nerve energies” states that kinds of perception are dependent on which neurons are activated, not what is activating them

Question 25

Charles Sherrington

Answer 25

- Fundamental principles of brain function, including neuronal communication and networks - Neuron Doctrine- principle that perception depends on combined activity of many specialized neurons, each of which responds to specific aspects of stimulus

Question 26

Wilder Penfield

Answer 26

- Constructed "touch map" (touch brain --> see body movement) showing how perceived location of body surfaces touched corresponded to location of brain neural activity - Neuroscientists in 1950s to 1960s found that: - Individual neurons in frog's brain respond to specific visual stimuli (vagus nerve stimulation) - Changes in physical stimuli produce corresponding quantitatively precise changes in neural activity

Question 27

Typical neuron

Answer 27

distinguished from other types of cells: - communication and information movement is different from other cells - hyperconnectivity (lots of connections across synapses)

Question 28

Ions in resting membrane potential

Answer 28

- Higher Na+ outside axon | - Higher K+ and A- inside axon

Question 29

Transmitting signals between neurons

Answer 29

- Synapses can excite or inhibit the cells they influence - Excitatory: Post-synaptic (receiving) cells depolarize (more positive) - Inhibitory: Post-synaptic cells hyperpolarize (more negative)

Question 30

Binding of NTs at excitatory synapses causes ___ ion channels to open, allowing ___ ions to enter the neuron and creating an ____

Answer 30

Na+, Na+, EPSP

Question 31

Binding of NTs at inhibitory synapses causes ___ ion channels to open, allowing ___ ions to enter the neuron and creating an ____

Answer 31

Cl-, Cl-, IPSP

Question 32

The Human Brian

Answer 32

- Size - 300 billion neurons organized into dozens of anatomically and functionally distinct regions - Number of synapses in the brain exceed 100 trillion - Brain weighs about 1.3 kg - Gray matter outside, white matter inside - Divisions and connections - Major divisions: right and left cerebral hemispheres - Major hemispheric connection: corpus callosum - Most important subcortical structure: thalamus - most neural signals originating in sensory organ pass through thalamus on the way to cortex

Question 33

Cognitive Neuropsychology

Answer 33

damage to a particular area of the brain typically causes a deficit in a specific cognitive or perceptual function - info about structures when dysfunction is occuring - depends on modularity- complex tasks require coordination among many modules - Functional modularity: each cognitive system has a module - Anatomical modularity: certain brain areas have a cognitive function

Question 34

Pierre Paul Broca

Answer 34

discovered that speech production center of brain is located in region of left frontal lobe (Broca's area)

Question 35

Dissociation

Answer 35

pattern of brain damage and impaired function in which damage to some specific brain region is associated with impairment of some specific function but not with impairment of another function

Question 36

Double Dissociation

Answer 36

pattern of brain damage and impaired function in which damage to some specific brain region is associated with impairment of some specific function (A), but not with impairment of another function (B) along with a pattern in which damage to different region is associated with impairment of function B but not with impairment of function A

Question 37

Functional Neuroimaging

Answer 37

- techniques to measure healthy brain activity - EEG- uses electric field to measure surface level activity - MEG- uses magnetic field to measure surface level activity - PET- measures changes in bloodflow and brain activity with radioactive substance - can't see changes taking place in short periods of time - fMRI- used for detecting the changes in blood oxygenation and flow that occur in response to neural activity - can be used to produces activation maps showing which parts of the brain are involved in a particular mental process

Question 38

Diffuse Optical Tomography

Answer 38

- refers to emerging type of brain imaging - senses changes in the blood oxygen level in the brain, but does so by using optical techniques - employs array of near- infrared light sources and sensors that measure changes in the light reflected by the brain, caused by changes in blood flow - has some advantages over PET and fMRI