Unit 4

Question 1

A person if falling from a building, which direction will the hair cells in the semicircular canals point?

Answer 1

Up, opposite to the gravity/inertial force

Question 2

When you tilt your head back, which directions are the hair cells pointing?

Answer 2

Back

Question 3

While driving a car forward at a constant speed of 45m/hr, which directions are your hair cells pointing towards?

Answer 3

Resting because acceleration = 0

Question 4

As you turn your head to the right, what is happening in the right horizontal canal?

Answer 4

The right horizontal canal hair cells are excited while the hair cells on the left horizontal are inhibited

Question 5

As you examine your patient’s eyes you notice that she seems to be performing slow eye movements to the right and then quickly resetting to the left. Which side’s horizontal canal seems to be damaged here?

Answer 5

Right horizontal canals

Question 6

Your patient has severe build up of fluid in his left semicircular canals that damaged his hair cells. When he walks, he seems to be off balance and staggering. On which side is he leaning and which muscle is overactive?

Answer 6

Left leaning with right extensors inappropriately active

Question 7

What are the three basic types of evidence used to understand the function of the cerebellum?

Answer 7

Anatomical, physiological, and studies (clinical, path or behavioral)

Question 8

What is the difference between efference and reafference?

Answer 8

Efference is having a copy already for the movement while reafference is receiving sensory feedback for the movement

Question 9

Which has a greater frequency: complex or simple spikes?

Answer 9

Simple spikes

Question 10

In which stage is the majority of our sleep taking place?

Answer 10

Stage 2: 49%

Question 11

During which stage of the sleep, do nighttime erections usually happen?

Answer 11

REM

Question 12

During REM is the sympathetic or the parasympathetic system dominating? during state IV?

Answer 12

Sympathetic during REM and parasympathetic during stage IV

Question 13

What are some problems that the elderly encounter with sleep?

Answer 13

They sleep for shorter times and the stage III and IV sleep is smaller so that they spend less time in deep sleep, which results in them going to sleep early and waking up at ungodly hours

Question 14

What are the 4 monoamines involved in keeping you awake?

Answer 14

NE, histamine, dopamine and serotonin

Question 15

Does GABA FROM the basal forebrain promote wakefulness or sleepiness?

Answer 15

Wakefulness

Question 16

Your 25 year old patient reports being anxious and worried during bedtime and unable to fall asleep? Which neurotransmitter is to blame?

Answer 16

Norepinephrine from the locus coeruleus

Question 17

Your patient complains of inability to stay awake. You notice that although her histamine levels and production is fine, she is still having these problems. Why?

Answer 17

Her H3 autoreceptors might be defective and thus not provide inhibitory feedback to themselves to promote wakefulness

Question 18

Where is Orexin/Hypocretin produced?

Answer 18

lateral hypothalamus

Question 19

If you are unable to go into REM sleep, where is the lesion likely located?

Answer 19

BF/LDT/PPT and no Ach is being released

Question 20

A patient comes into your office complaining of impotency but he seems to have erections occurring involuntarily in the night. What can you do to help the patient?

Answer 20

Refer him, this is a psychological issue

Question 21

How does caffeine make you feel like its 1pm when its 4pm?

Answer 21

Caffeine removes the adenosine from its receptors, making us believe we have the adenosine concentration on 1pm

Question 22

What is the physiology behind the caffeine crash?

Answer 22

Once the caffeine wears off, all the displaced adenosine goes back to their receptors and their concentration hits us suddenly and makes us tired

Question 23

How do the complementary genes PER/CRY and Clock/BMAL maintain the 24 hr cycle?

Answer 23

Its take each pair 24 hrs to build up enough concentration to flip back and forth

Question 24

What two internal factors most control the circadian rhythm?

Answer 24

The genes and the SCN of the hypothalamus

Question 25

You know your keys are kept on top of the dresser without even seeing them there and you poin them out for your friend. Which pathway is responsible for this action?

Answer 25

Dorsal pathway (proximal limb muscle)

Question 26

You go to pick up a sharp shard of glass. In careful picking it up, which pathway are you activating?

Answer 26

Ventral stream (distal muscles)

Question 27

Your patient has hemi-neglect syndrome. Which stream is most likely defective?

Answer 27

Dorsal stream

Question 28

A research notices that a lab monkey's neurons fire up when she is paying attention to a banana that is just beyond her cage. Where is this neuron likely located?

Answer 28

Posterior parietal- attention/intention

Question 29

Why does a lab monkey's prefrontal cortex become active when tested with a cue and delay experiemnt?

Answer 29

Because this is a short-term working memory task

Question 30

What are the 4 processes of speech?

Answer 30

Respiration, phonation, articulation, resonation

Question 31

What are the 5 dimensions of language?

Answer 31

Morphology, phonology, syntax, semantics and pragmatics

Question 32

A lesion in the arcuate fibers will result in what difficulty?

Answer 32

Conduction aphasia: difficulty speaking out the words, mixing them up since the information from wernicke's is not reaching broca's

Question 33

What is one similarity between area 44 of Broca's and the supermarginal gyrus?

Answer 33

They are both involved in phonology

Question 34

What is one similarity between area 45 of Broca's and the angular gyrus?

Answer 34

They are both involved in semantics of language

Question 35

What are the two ways that the STN can be excited?

Answer 35

Through the indirect and the hyperdirect pathways

Question 36

As the you move along the cochlea from the base to the apex, how does the stiffness change?

Answer 36

It decreases

Question 37

What is the consequence of the decreased stiffness from the base to the apex of the cochlea?

Answer 37

There is a phase lag

Question 38

As frequency of a sound increases, what happens to the distance along the basilar membrane traveled?

Answer 38

It decreases (stays closer to the stapes)

Question 39

What allows hair receptors to differentiate between different tactile stimuli?

Answer 39

Unique accessory properties of the receptors

Question 40

What are the two properties that contribute to epicritic discrimination?

Answer 40

Receptor density and receptive field size

Question 41

Which of the following receptors is the best at discriminating the spatial properties of a touch stimuli? a. Pacinian b. merkels c. meissners d. ruffins

Answer 41

b and d

Question 42

Why are sensations from the face and hands so over-expressed in the cortex?

Answer 42

Highest density of receptors with smallest receptive fields

Question 43

If you burn the tip of your finger, why does the rest of your finger become sensitive as well? What substance is responsible for this?

Answer 43

This is mechanical hyperaglesia and is caused by the spinal cord release of substance P inhancing histamine etc both locally and globally

Question 44

Why would the phantom limb phenomena occur in patients of motor vehicle accidents?

Answer 44

The MVA can cause brachial plexus avulsion that can shift the balance in the spinal cord, making there be nociceptive input that is just not there

Question 45

What kind of stimuli do wide dynamic range neurons respond to?

Answer 45

Both nociceptive and somatosensory

Question 46

How do opiates inhibit nociceptive sensations?

Answer 46

They inhibit release of substance P, glutamate etc from neurons

Question 47

Which cells allow the efficient clean up of myelin debris following PNS damage?

Answer 47

Macrophages, astrocytes and schwann cells

Question 48

How does the Schwann cell play a key role in the regeneration of the damages PNS neuron?

Answer 48

By helping elongate and guiding and aligning the growing axon

Question 49

What receptors on the muscle cells help guide the re-growing axons towards the right targets?

Answer 49

Acetylcholine receptors

Question 50

How is Wallerian degeneration different in the PNS and the CNS?

Answer 50

In the PNS it is efficient throughout the process, while in the CNS it is hampered by the myelin debris that is not effectively cleared plus the glial scar formed in an attempt to limit tissue damage.

Question 51

What are the cells attempting to clear debris in the case of CNS damage?

Answer 51

Microglia and oligodendrocytes

Question 52

What is one aspect of regeneration that the PNS and CNS have in common? 1. Surivival of neuron cell body 2. Clearance of debris 3. New axonal growth promotion 4. Guidance cues

Answer 52

1- survival of new nerve cell bodies

Question 53

How does chondrotinase ABC promote axon regeneration?

Answer 53

It inhibits proteoglycans in the CNS, allowing a better environment for axon growth

Question 54

What are some structures present in the original papez circuit that are now known to be not as important?

Answer 54

Hippocampus, posterior cingulate and mammillary bodies

Question 55

What are the 7 structures now known to be important in the papez circuit?

Answer 55

Anterior/mid-cingulate, PAG, hypothalamus, Amygdala, ANS, DRN, LC

Question 56

Name the papez circuit structure important for memory storage and enhancement.

Answer 56

LC (through the NE dump on Amygdala), ANS

Question 57

What are the 3 structures most involved in primary emotions?

Answer 57

Amygdala, hypothalamus, PAG

Question 58

In an experiment, scientists train a mouse to anticipate a shock at the ring of a tone. They then cut the projections from the auditory cortex and find that the mouse still reacts to the tone fearfully. How?

Answer 58

The amygdala has direct projections from the thalamus (MGN) and can have a primary fear response without cortical processing.

Question 59

PAG produces different classes of behavior depending on the activation of either the lateral or the ventrolateral portion (lighter). What are these behaviors?

Answer 59

The lateral (darker) region produces the flight response with tachycardia and hypertension while the ventrolateral (lighter) side produces the quiescence, bradycardia and hypotension

Question 60

In a lab mouse, the projections from the lateral hypothalamus to the PAG were activate excessively. What is the behavior to expect here?

Answer 60

Sham Rage

Question 61

electrical simulation of a component of the limbic system produces complex motor outputs such as lip puckering. What is this region likely?

Answer 61

Mid-cingulate cortex

Question 62

Why are SSRIs so successful in treating psychiatric patients?

Answer 62

The ACC has one of the highest concentrations of receptors for SSRIs, making them efficient since the ACC is a major area for secondary emotional processing.