Unit 2: Neurons and Research Methods

Question 1

Lesioning

Answer 1

destruction of brain tissue; victims of severe brain injury, Parkinson’s/schizophrenic/OCD patients

Question 2

Electroencephalograph (EEG)

Answer 2

monitors brainwave pattern produced by electrical activity of brain; sleep stages, tumors, seizure disorders

Question 3

Electrical stimulation of brain (ESB)

Answer 3

process where a weak electrical current is sent into brain structure to stimulate it; animal research

Question 4

Computer tomography (CT)

Answer 4

brain imaging method that utilizes computer-controlled x-rays of brain; gives composite representation (,ap) of brain slices; stroke damage, blood clots, tumors, injuries

Question 5

Positron Emission Tomography (PET)

Answer 5

brain-imaging method where radioactive glucose is injected into subject; can monitor brain activity like sleep cycles

Question 6

Magnetic Resonance Imaging (MRI)

Answer 6

technique uses magnetic fields and radioactive waves to produce computer generated images that distinguish among different types of soft tissue; allows to see smaller details and structures within brain

Question 7

Functional MRI (fMRI)

Answer 7

new variation on MRI technology that monitors blood flow and oxygen consumption in brain to identify areas of high activity

Question 8

CT vs MRI

Answer 8

CTs are less expensive; CTs are less sensitive to patient movement; CT scans can be performed in presence of implanted medical device

Question 9

Central nervous system (CNS)

Answer 9

contains spine and brain

Question 10

Peripheral nervous system (PNS)

Answer 10

sensory and motor neurons that connect CNS with rest of body; contains Autonomic and Somatic nervous systems

Question 11

Autonomic nervous system

Answer 11

controls involuntary functions or items that happen automatically within body; contains Sympathetic and Parasympathetic nervous systems

Question 12

Somatic nervous system

Answer 12

controls voluntary movements and communication to and from the sense organs

Question 13

Sympathetic nervous system

Answer 13

physically arouses body, preparing it to act/react in stressful situations, expends energy; initiates fight-or-flight; inhibits digestion, dilates pupils, increases breathing and heartrate to oxygenate blood, stimulates release of epinephrine and norepinephrine by adrenal gland

Question 14

Parasympathetic nervous system

Answer 14

calms body, conserving its energy and helping keep a constant internal state; returns body to homeostasis; initiates rest and digest; stimulates digestion, contracts pupils, slows breathing and heartrate

Question 15

Sensory neurons

Answer 15

afferent neurons; carries incoming messages/information from sense receptors to CNS

Question 16

Motor neurons

Answer 16

efferent neurons; carries outgoing information from CNS to the peripheral nervous system and muscles

Question 17

Resting potential

Answer 17

when neuron is not firing, and has a negative charge with mostly potassium ions inside and mostly sodium ions outside

Question 18

Polarization

Answer 18

at resting potential, when NA is outside and K is inside; at this state, neuron is at homeostasis; should strive to obtain this regularly

Question 19

Action potential

Answer 19

nerve impulse; electrical pulse or message that travels length of axon

Question 20

All or nothing principle

Answer 20

when nucleus decides to fire, it fires down axon completely (all the way) or not at all; maintains same intensity the entire length of axon regardless of strength of intent

Question 21

Depolarization

Answer 21

Sodium and positive ions rush in, causing potassium and negative ions to rush out; takes longer for potassium channels to open, so neurons struggle to fire; action potential

Question 22

Refractory period

Answer 22

period of time after firing that neuron is focused on resetting, and therefore unable to fire again

Question 23

Neurotransmitters

Answer 23

chemical substance that crosses synapse to carry on message to next neuron

Question 24

Synapse

Answer 24

open space between two neurons where neurotransmitters cross

Question 25

Receptor sites

Answer 25

specific points on dendrites of neurons that receive specific types of neurotransmitters

Question 26

Agonist

Answer 26

external substance that somehow interact with neurotransmitters at receptor sites on dendrites of neuron; mimics neurotransmitter activity; anesthesia (morphine mimics endorphins)

Question 27

Antagonist

Answer 27

external substance that somehow interact with neurotransmitters at receptor sites on dendrites of neuron; blocks neurotransmitter activity; prevents neurotransmitter from getting to receptor site; botox

Question 28

Reuptake

Answer 28

process where neurotransmitter molecules that have been released by synapse are reabsorbed by presynaptic neuron that released them

Question 29

axon

Answer 29

part of neuron that carries nerve impulse away from cell body

Question 30

dendrite

Answer 30

part of neuron that increases receptive surface of neuron; receives communications from other cells

Question 31

Interneurons

Answer 31

only neurons in CNS; act as messengers between sensory and motor neurons