L4

Question 1

What 3 processes occur as a physiological response is brought about by a physical stimulus?

Answer 1

transduction, information processing, sensory coding

Question 2

Transduction

Answer 2

how energy in the environment gets transformed into electrical energy by the nervous system

Question 3

Information processing

Answer 3

what happens to the electrical signals as they travel through the nervous system to the brain

Question 4

Sensory coding

Answer 4

how the brain understands what the electrical signals reaching it mean

Question 5

Doctrine of specific nerve energies

Answer 5

the nature of a sensation depends on which nerves are stimulated, not how the nerves are stimulated (e.g. stimulation of optic nerve by light or touch produces the sense of vision)

Question 6

Reasoning behind the doctrine of specific nerve energies

Answer 6

neural signals are identical across sensory modalities

Question 7

Cranial nerves

Answer 7

12 pairs of nerves that originate in the brain stem or thalamus and reach the periphery through openings in the skull

Question 8

3 cranial nerves that carry only sensory information

Answer 8

olfactory (I), optic (II), vestibulocochlear (VIII) comprising of the auditory and vestibular nerve

Question 9

Functions of olfactory, optic, and vestibulocochlear nerves

Answer 9

smell; vision; spatial orientation, balance, hearing

Question 10

4 cranial nerves that carry both sensory and motor information

Answer 10

trigeminal (V), facial (VII), glossopharyngeal (IX), vagus (X)

Question 11

Body parts associated with the trigeminal nerve

Clue: tri and gem!

Answer 11

face, sinuses, teeth

Question 12

Body parts associated with the facial nerve

Answer 12

tongue and soft palate

Question 13

Body parts associated with the glossopharyngeal nerve

Answer 13

posterior tongue, tonsils, pharynx, pharyngeal muscles

Question 14

Body parts associated with the vagus nerve

Answer 14

heart, lungs, gastrointestinal tract, bronchi, trachea, larynx

Question 15

Synapse

Answer 15

junction between neurons that permit information transfer

Question 16

Neurotransmitter

Answer 16

chemical substance used in neuronal communication at synapses

Question 17

How do action potentials occur?

Answer 17

sodium channels open when a neuron’s membrane potential reaches a threshold, causing sodium ions (+) to rush in and depolarize the neuron

Question 18

Electroencephalography (EEG)

Answer 18

electrodes on scalp measure event-related potentials (voltage changes) while the subject performs a perceptual task

Question 19

Pro and con of EEG

Clue: electric!

Answer 19

good temporal resolution but poor spatial resolution

Question 20

Magnetoencephalography (MEG)

Answer 20

measures magnetic fields created by the flow of ion currents between neurons using magnetometers

Question 21

Pros and cons of MEG

Answer 21

high temporal resolution and good spatial resolution (better than EEG) especially when used with structural MRI; difficult to measure signals deep in brain

Question 22

Positron emission tomography (PET)

Answer 22

a radioactive tracer (e.g. oxygen) is injected into the subject and positrons are emitted and picked up by the scanner

Question 23

Pros and cons of PET

Answer 23

good for studying disease and brain chemicals; poor temporal and spatial resolution (can be improved if used with MRI); invasive

Question 24

Structural MRI

Answer 24

a large magnet obtains high-res images of the body based on differences in water content; best spatial resolution of all neuroimaging techniques

Question 25

How is a stronger fMRI signal produced?

Answer 25

neural activity > increased blood flow and oxygen to active neurons > oxygen consumption (but not all) > oxygen in venous blood > stronger signal

Question 26

Pros and cons of fMRI

Answer 26

non-invasive; good spatial resolution (same machine as structural MRI but used differently) but response changes very slowly