Neuropsychology

Question 1

reflex

Answer 1

an automatic movement produced as the direct result of stimulus

Question 2

First step in reflex pathway?

Answer 2

Information received from receptors in skin/muscle

Question 3

Second step in reflex pathway?

Answer 3

Information transmitted through afferent (sensory) neurons

Question 4

Third step in reflex pathway?

Answer 4

Information received by interneuron in spinal cord and sent to brain and other interconnected body parts

Question 5

Fourth step in reflex pathway?

Answer 5

Information transmitted to efferent (motor) neurons

Question 6

Fifth step in reflex pathway?

Answer 6

Muscle contraction resulting in reflexive motor output

Question 7

Approximately how many neurons does an individual have?

Answer 7

86 billion

Question 8

Approximately how many connections does each neuron have?

Answer 8

10,000

Question 9

dendrites

Answer 9

“input” branched part of neuron that receives impulses and conducts them toward cell body

Question 10

cell body (AKA “soma”)

Answer 10

part of neuron containing nucleus and metabolic functions

Question 11

axon

Answer 11

“output” part of neuron that transmits impulses to glands, muscles, or other neuron

Question 12

terminals

Answer 12

buttons along the endings of the axon like water balloons filled with neurotransmitters

Question 13

myelin sheath

Answer 13

segments of myelin that wrap around axon to provide insultation

Question 14

Nodes of Ranvier

Answer 14

gaps between myelin sheath that speed up nerve impulses along myelinated axons

Question 15

nerve impulse (AKA action potential)

Answer 15

the means through which individual neurons communicate with each other

Question 16

multiple sclerosis

Answer 16

autoimmune disease where the immune system treats myelin sheath as “foreign body” and attacks it

Question 17

MS results in…

Answer 17

demyelination of neurons which prevents action potentials from occurring properly; signal do not reach muscles (loss of movement ability)

Question 18

First step in a nerve impulse?

Answer 18

Stimulus occurs; Some Na+ ions flow in neuron

Question 19

resting potential

Answer 19

-70 mV; Cl- ions inside of neuron while Na+ ions outside

Question 20

Second step of nerve impulse?

Answer 20

If threshold (-55 mV) is reached, full depolarization occurs by allowing Na+ ions to flow into the neuron through a channel

Question 21

Third step of nerve impulse?

Answer 21

K+ ions flow out of neuron and hyperpolarize it

Question 22

Fourth step of nerve impulse?

Answer 22

Cell is hyperpolarized to -90 mV

Question 23

Fifth step of nerve impulse?

Answer 23

Na+ and K+ are moved back to their natural state (via Na+/K+ pump) so that cell is back at resting potential

Question 24

-55 mV is a…

Answer 24

threshold in which below that voltage there is no action potential.

Question 25

Firing is...

Answer 25

"all-or-nothing." The -55 mV must be met for a neuron to fire.

Question 26

More intense stimulation causes...

Answer 26

more frequent actional potential and more action potential in more neurons; not more intense action potential.

Question 27

Action potential travels...

Answer 27

down length of axon by depolarizing neighboring areas.

Question 28

Action potential travels at...

Answer 28

50-100 m/sec; not at speed of electrical current in wire.

Question 29

For action potential to occur, the inside of the cell must...

Answer 29

depolarize (become more positive).

Question 30

synapse

Answer 30

gap between two neurons consisting of presynaptic and postsynaptic neurons' membranes and space between them

Question 31

Sherrington inferred...

Answer 31

that there must be a break in communication system of neurons (synapse); proved through temporal and spatial summation

Question 32

temporal summation

Answer 32

stimulus is repeated at same place within a small period of time

Question 33

Terminal endings of presynaptic neurons...

Answer 33

replay impulse to dendrites of postsynaptic neuron.

Question 34

Terminal buttons contain...

Answer 34

vesicles of neurotransmitters that burst into synapse at action potential.

Question 35

Receptor molecules on membrane of dendrite...

Answer 35

are locks to be opened by neurotransmitters. They open the ion gates to allow Na+ into the cell.

Question 36

neurotransmitters

Answer 36

chemicals that send signals across synapses

Question 37

Neurotransmitters may open a gate to...

Answer 37

let Na+ inside because potential is getting smaller (toward -55 mV) or push K+ ions out because potential is getting larger (toward -70 mV).

Question 38

excitatory

Answer 38

more likely to fire

Question 39

An excitatory connection means...

Answer 39

the neurotransmitter make the postsynaptic cell more likely to fire by activating receptor molecules that allow more Na+ ions inside.

Question 40

inhibitory

Answer 40

less likely to fire

Question 41

Inhibition and excitation are...

Answer 41

opposite forces.

Question 42

Inhibition is a...

Answer 42

negative force.

Question 43

Excitation is a...

Answer 43

positive force.

Question 44

An excitatory connection means...

Answer 44

the neurotransmitter make the postsynaptic cell more likely to fire by activating receptor molecules that allow more Na+ ions inside.

Question 45

MS results in...

Answer 45

demyelination of neurons which prevents action potentials from occurring properly; signal do not reach muscles (loss of movement ability)

Question 46

MS results in...

Answer 46

demyelination of neurons which prevents action potentials from occurring properly; signal do not reach muscles (loss of movement ability)

Question 47

For action potential to occur, the inside of the cell must...

Answer 47

depolarize (become more positive).

Question 48

For action potential to occur, the inside of the cell must...

Answer 48

depolarize (become more positive).

Question 49

Neurotransmitters are released...

Answer 49

from vesicles in terminals that fuses with membrane, allowing neurotransmitters to flow out.

Question 50

Receptors on dendrites of postsynaptic neurons...

Answer 50

receive neurotransmitters that trigger the opening of sodium channels.

Question 51

serotonin

Answer 51

associated with long-term happiness, calmness, overall wellbeing

Question 52

Selective serotonin reuptake inhibitors (SSRIs)...

Answer 52

prevent the reuptake of neurotransmitters, meaning more will bind to the postsynaptic receptors.

Question 53

dopamine

Answer 53

associated with short-term happiness, euphoria, pleasure, etc

Question 54

inhibitory post-synaptic potential (IPSPs)

Answer 54

inhibitory neurotransmitter binds to cell membrane and prevents another action potential from occurring

Question 55

IPSPs...

Answer 55

pump K+ ions out of cell and Cl- into cell to hyperpolarize it and prevent action potential; serotonin in inhibitory

Question 56

excitatory post-synaptic potential (EPSPs)

Answer 56

excitatory neurotransmitter binds to cell membrane and encourages another action potential to occur

Question 57

EPSPs...

Answer 57

pump Na+ ions into cell to depolarize it and facilitate action potential; dopamine is excitatory

Question 58

reciprocal inhibition

Answer 58

when one muscle is excited and contracts, its counterpart muscle is inhibited

Question 59

reciprocal inhibition

Answer 59

when one muscle is excited and contracts, its counterpart muscle is inhibited