Chapter 3

Question 1

what are neurons, how many does brain contain

Answer 1

“building blocks of mind”

cells in nervous system that communicate w each other to perform information-processing tasks

86 billion in human brain

Question 2

Structures of neuron, which direction does info flow?

Answer 2

1. Dendrites: receives info from other neurons
2. Soma (cell body): coordinates info processing task
3. Axon: carries info to other neurons/muscles/glands

**info flows from dendrites to axon

Question 3

Types of neurons (based on function)

Answer 3

Sensory neurons: Carry info from body to brain (feeling something hot)
Motor neurons: Instructions from brain to body (ex moving hand away)
Interneurons: Connect sensory and motor neurons to help them communicate

Question 4

How is neuronal communication an electrochemical process

Answer 4

Conduction (electrical): movement of electrical signal WITHIN neurons

Transmission (chemical): the movement of chemical signal ACROSS neurons

Question 5

Resting vs action potential of neuronal communication during conduction

Answer 5

Resting: natural negative electric charge of neurons (bc there are more positive ions Na+ on outside)
Action: an electrical signal conducted along a neuron’s axon, neuron sends signal and Na+ ions rush inside so it becomes more pos. this electrical impulse travels down the neuron then it passes and neuron resets to resting potential

Question 6

How does a neuron regulate the neg charge while resting

Answer 6

pumps 3 Na+ out and 2 K+ in

Question 7

How does charge of neuron change when active (neuron fires)

Answer 7

1. Sodium channels open and Na+ rushes in depolarization inside becomes positive this causes the signal
2. Potassium channels open, K+ flows out repolarization and inside goes back to negative
3. After action potential… sodium potassium pump restores balance with more K+ inside more Na+ outside (even if neuron is too neg for a moment)

Question 8

Single-Unit Recordings and ex

Answer 8

method to analyze firing patterns of single neurons

og purpose of this study on monkey was neurobiology of arm movements (observing)

“mirror neurons”: same neuron fires whether monkey performs action or watches someone else perform action

Question 9

Electroencephalography (EEG)

Answer 9

neuroimaging method that records brain electrical activity via electrodes placed on scalp

Question 10

Transcranial Magnetic Stimulation (TMS)

Answer 10

neuroimaging technique that activates or deactivates regions of the brain via magnetic pulse

Question 11

Synapse gap/cleft

Answer 11

region between axon of one neuron and dendrites of another

axon (message leaves): presynaptic neuron
dendrites (message received): postsynaptic neuron

Question 12

Neurotransmitters after they bind to receptors

Answer 12

1. diffusion: neurotransmitter drift out of synapse
2. enzyme deactivation: synaptic enzymes breakdown neurotransmitters
3. reuptake: neurotransmitter absorbed back by presynaptic neuron

Question 13

agonist drugs

Answer 13

drugs that increase the action of a neurotransmitter

ex: increasing production, release, bind and activate post-synaptic receptor, blocking reuptake of neurotransmitters

Question 14

antagonist drugs

Answer 14

drugs that diminish function of neurotransmitter

ex: binding to receptor sites and blocking neurotransmitters, blocking production/release

Question 15

“all or none” event

Answer 15

action potential (neuron either fires fully or not at all)

Question 16

thalamus and what info does it receive

Answer 16

relay station in the brain, receives major sensory except for smell (vision, touch, taste, sound)

Question 17

neurons communicate (electrically/chemically) with each other at the (synapse/dendrites/axons)

Answer 17

electrical signal passes through neuron. chemical signal leaves the axon, so at the synapse (gap between axon and dendrite), it’s a chemical signal. dendrite receives that chemical signal

neurons communicate chemically with each other at the synapse