Chapter 2

Question 1

cells that convey sensory information into the brain, carry out operations, and transmit commands to the body

Answer 1

neurons

Question 2

specialized neurons that respond to specific kinds of energy

Answer 2

Sensory receptors

Question 3

a state in which there is a difference in electrical charge between the inside and outside of the neuron

Answer 3

Polarization

Question 4

measure of the difference in electrical charge between two points

Answer 4

Voltage

Question 5

difference in charge between inside & outside of membrane of a neuron at rest

Answer 5

Resting potential

Question 6

abrupt depolarization of membrane that allows neuron to communicate, Lasts about 1 millisecond
When neurons are “firing,”-Axon hillocks

Answer 6

Action potential

Question 7

What do we use to Record Electrical Signals in Neurons

Answer 7

Small electrodes are used to record from single neurons

Question 8

Recording electrode

Answer 8

Inside the nerve fiber

Question 9

Reference electrode

Answer 9

Outside the nerve fiber

Question 10

Meter

Answer 10

Records the difference in charge between the tips of the two electrodes

Question 11

Properties of Action Potentials

Answer 11

Show propagated response
Remain the same size regardless of stimulus intensity
Increase in rate to increase in stimulus intensity
Show spontaneous activity that occurs without stimulation, baseline, detect an increase or decrease- check the baseline

Question 12

Properties of Action Potentials- Show propagated response

Answer 12

Once the response is triggered, it travels down the full length of the axon without changing in size

Question 13

Properties of Action Potentials-Increase in rate to increase in stimulus intensity

Answer 13

Have a refractory period of 1 ms – upper firing rate is 500 to 800 impulses per second

Question 14

All or none law

Answer 14

once the action potential it’s going to occur at its full strength or not at all (not partial)

Question 15

Non decremental use

Answer 15

when the action potential travels, they don’t decrease in size as they go

Question 16

What Moves the Ions?

Answer 16

1- Force of diffusion
2-Electrostatic pressure
3- Sodium potassium pump

Question 17

Force of diffusion

Answer 17

tendency of ions to move through high concentrated membrane to less concentrated side

Question 18

Electrostatic pressure

Answer 18

force where ions are repelled from similarly charged, attracted to oppositely charged

Question 19

Sodium potassium pump

Answer 19

large protein molecules that move sodium ions through cell membrane to outside, potassium ions back inside

Question 20

Ion channels

Answer 20

gated pores in the membrane formed by proteins; limit the flow of ions into and out of the cell

Question 21

Ion Channels Can be _____ or ____

Answer 21

chemically gated, electrically gated

Question 22

Chemically gated

Answer 22

neurotransmitters or hormones

Question 23

Electrically

Answer 23

change in electrical potential of the membrane

Question 24

Where are the neurotransmitters stored at

Answer 24

synaptic vesicles

Question 25

Synapse

Answer 25

the connection between two neurons

Question 26

Synaptic cleft:

Answer 26

the small gap which separates neurons so they are not in direct physical contact at the synapse

Question 27

Presynaptic is the_____ neuron

Answer 27

transmitting neuron

Question 28

Postsynaptic is the ___ neuron

Answer 28

receiving neuron

Question 29

Two types of responses can occur at the receptor sites

Answer 29

1- excitatory 2- inhibitory

Question 30

Excitatory transmitters

Answer 30

cause depolarization Neuron becomes more positive Increases the likelihood of an action potential

Question 31

Inhibitory transmitters

Answer 31

cause hyperpolarization Neuron becomes more negative Decreases the likelihood of an action potential

Question 32

Specificity coding

Answer 32

A specialized neuron that responds only to one concept or stimulus

Question 33

Sparse coding

Answer 33

occurs when a particular stimulus is represented by a pattern of firing of only a small group of neurons, with the majority of neurons remaining

Question 34

Population coding

Answer 34

proposes that our experiences are represented by the pattern of firing across a large number of neurons A large number of stimuli can be represented, because large groups of neurons can create a huge number of different patterns

Question 35

Modularity:

Answer 35

the idea that specific brain areas are specialized to respond to specific types of stimuli or functions Each specific area is called a module

Question 36

Phrenology

Answer 36

is a process that involves observing and/or feeling the skull to determine an individual's psychological attributes

Question 37

speech production area

Answer 37

Broca’s area

Question 38

area in the temporal lobe which was involved in understanding speech

Answer 38

Wernicke’s area

Question 39

Distributed representation:

Answer 39

idea that the brain represents information in patterns distributed across the cortex, not just one brain area The distributed approach to representation focuses on the activity in multiple brain areas and the connections between those areas

Question 40

Structural connectivity is the

Answer 40

“road map” of fibers connecting different areas of the brain

Question 41

Functional connectivity

Answer 41

is the neural activity associated with a particular function that is flowing through this structural network

Question 42

Electroencephalography (EEG)

Answer 42

Measures electrical activity via electrodes Can be Inter- or Intra-cranial Electrodes either on or in the skull Very good time resolution Milliseconds

Question 43

Computerized Tomography (CT or CAT)

Answer 43

Builds a picture of the brain based on the differential absorption of X-rays Reveals gross features of the brain Does not resolve brain structure well

Question 44

Functional Magnetic Resonance Imaging (fMRI)

Answer 44

Detects changes in blood oxygenation, blood flow Tied to neural activity High activity = high oxygen use and high blood flow

Question 45

Diffusion Tensor Imaging (DTI)

Answer 45

Builds a picture of water movement in the brain using an MRI scanner Observe blood flow along specific neural tracts High spatial resolution and directionality

Question 46

Near Infrared Spectroscopy (NIRS)

Answer 46

Measures changes in blood oxygenation Shines near IR light through the skull Detects attenuation of reemerging light Indirect measure of brain activity

Question 47

Connections Between Brain Areas

Answer 47

1- Structural connectivity 2- Functional connectivity