NRSC Exam 4

The investigators found that

(A and B) Having a male in the room significantly increased plasma corticosterone in mice AND Having a shirt worn by a male in the room significantly increased plasma corticosterone in mice

In rats, which of the following exercise conditions has been shown to protect against the shuttle-box escape deficits caused by inescapable tail shock stress exposure (IS)

(A and B) 6 weeks of voluntary wheel running AND 6 weeks of forced wheel running

In Figures 1 and 3, the authors measure prepulse inhibition. Which of the following is true?

(A and B) In this experiment, the "prepulse" referred to a short burst of noise, 4, 8 or 16 dB above the background noise level, prior to a louder noise stimulus AND When measuring prepulse inhibition, the researchers recorded the startle response of each mouse in response to a short, loud noise stimulus

When muscimol binds to GABAA receptors on a neuron, it

(A and B) mimics the action of GABA AND causes the neuron to be hyperpolarized (it does not cause an action potential)

In rats, 6 weeks of voluntary wheel running has been shown to reduce stress-induced Fos expression (used as a marker of brain activation) in which of the following brain regions?

(A and B) paraventricular nucleus of the hypothalamus AND dorsal raphe nucleus

Which of the following is/are true?

(A and C) Stress tends to increase core body temperature AND An increase in thigmotaxis is indicative of an increase in anxiety-like behavior

Exposure to inescapable tail shock in rats leads to

(A and C) a decrease in social exploration of a juvenile rat AND an increase in latency to escape from a subsequent escapable stressor (e.g. in the shuttle box escape test)

In an experiment to look at the effect of behavioral control over a stressor, as well as the inescapable (IS) and escapable (ES) tail shock stress groups, there is also a control group that is restrained.True or False? This control group is included because of the fact that restraint is also a stressor, and it is important to compare the effects of intense tail shock with that of a milder, unrelated stressor.

false

True or False? By definition, for a person to be considered stress resilient, they MUST have a lower cortisol response to a stressor.

false

True or False? Giving a patient control of his/her own pain medicine after surgery has been shown to reduce the patient's stress levels, but has the downside that more medication is used.

false

True or False? Habituation of responses to one stressor will generalize to a different stressor. i.e. if you habituate your responses to one stressor, your responses to another stressor will also be decreased.

false

True or False? Habituation of responses to repeated presentation of a stressor are longer lasting if the stressor presentations occur very close together (minutes apart) rather than further apart (24 h apart)

false

True or False? Having a lower latency in the shuttle box escape test is indicative of learned helpless behavior

false

True or False? In Fig. 2D, the researchers compare levels of tyrosine hydroxylase (TH) to beta-actin because beta-actin is a cytoskeletal protein important for structural integrity, and if levels of beta-actin decrease it suggests an overall decline in the general health of the cell (and therefore can explain any observed decrease in TH expression).

false

True or False? In people, an increase in plasma beta-endorphin is thought to cause an increase in euphoria.

false

True or False? In rats, although 6 weeks of voluntary wheel running produces effects of stress resilience to mild stressor exposure, 6 weeks of voluntary wheel running produces no effects of stress resilience to intense stressor exposure.

false

True or False? In rats, temporary inactivation of the raphe pallidus during repeated presentation of a stressor, prevents habituation of the heart rate response to a stressor observed on a subsequent test day, when the raphe pallidus is working under normal conditions.

false

True or False? Inescapable tail shock stress (IS) in rats elicits a larger magnitude and duration of HPA axis responses (ACTH and corticosterone release) than the equivalent physical amount of escapable tail shock stress (ES) in male rats.

false

True or False? Lesions of the medial prefrontal cortex prevent the "stress resilience" effects provided by 6 weeks of voluntary wheel running on shuttle box escape behavior deficits caused by prior inescapable tail shock stress in rats.

false

True or False? Relative to sedentary rats, in order to see an exercise-induced reduction in HPA axis responses to a mild stressor exposure, a rat must have continuous access to a running wheel for about 6 weeks.

false

True or False? Researchers have observed an increase in opioid receptor availability in the brain of athletes following a 2 hour run, which was correlated with a measure of euphoria, providing evidence for an opioid related runner's high.

false

True or False? The desire for control is thought to be a process learned during childhood development, that generally first develops around 2 years old, resulting in behavior in toddlers termed the "terrible twos".

false

True or False? The reason that 6 weeks of wheel running produces decreases in the HPA axis response to 85dB noise in rats, compared to the response in sedentary rats, is most likely because of changes in the regions involved in primary sensory (auditory) processing.

false

True or false? Active coping responses are focused on reducing the negative emotion associated with a stressor.

false

True or false? In rats, freezing responses to 2 foot shocks is a measure of escape behavior.

false

True or false? Inactivation of the ventromedial prefrontal cortex (vmPFC) during escapable tail shock stress (ES) exposure decreases the amount of serotonin released in the dorsal raphe nucleus (DRN) compared to ES under normal conditions in male rats.

false

True or false? Inactivation of the ventromedial prefrontal cortex (vmPFC) during inescapable tail shock stress (IS) exposure decreases the amount of serotonin released in the dorsal raphe nucleus (DRN) compared to IS under normal conditions in male rats.

false

True or false? Serotonin neurons project from the amygdala to the dorsal raphe nucleus.

false

True or false? When researchers say they have lesioned a brain region (for example with an excitotoxin such as ibotenic acid) they have temporarily inactivated it.

false

According to current hypothesis (as described by Maier & Watkins, 2010), and compared to a stressor that is inescapable, having behavioral control over a stressor in male rats leads to

greater activation of excitatory output neurons from the ventromedial prefrontal cortex (vmPFC)

The effect of males on pain responses in rodents was shown to

involve axillary secretions

Which of the following is true of muscimol?

it is a GABA-A receptor agonist

Nucleus A is necessary for eliciting the increase in heart rate in response to stressor exposure in rats. If you inject muscimol in Nucleus A of a rat before exposure to restraint stress, what would most likely happen to the rat's heart rate?

it would be decreased relative to rats that were exposed to the restraint stressor without muscimol injection

You present 100 dB white noise to a rat for 30 min. and find that it causes an increased release of ACTH and corticosterone. You do the same thing every day for a week. After the 7th noise exposure you find that the ACTH and corticosterone levels are the same as basal values, as if the animal has not been exposed to a stressor at all. You put the rat back in its home cage, and don't do anything else for 3 weeks. You then expose it to the same noise stress. In response to this noise stress presentation, you would expect to see

levels of ACTH and corticosterone close to basal values

The mouse grimace scale was used to assess pain. Which of the following is true about this test?

none of the above (NOT It requires an observer to be present in the room with the mouse to monitor the pain levels, It involves measuring latency of paw withdrawal, or It involves measuring latency of tail withdrawal)

Which of the following is interpreted as an increase in pain experienced by an animal

none of the above (NOT an increase in tail withdrawal latency, an increase in paw withdrawal latency, or an increase in withdrawal threshold in the von Frey test)

In addition to changes in dopamine regulation in the GXE mice, the authors saw a significant decrease in total norepinephrine (ng/g tissue) in the

none of the above (NOT frontal cortex, caudate putamen, or nucleus accumbens)

Which of the following has been shown for inescapable tail shock stress exposure (IS), compared to escapable tail shock exposure (ES) in male rats?

none of the above (not during the tail shock exposure, levels of serotonin in the dorsal raphe nucleus (DRN) are lower, during the tail shock exposure, levels of serotonin in the basolateral amygdala (BLA) are lower, or fewer serotonin neurons express FOS protein in the DRN)

In male rats with no prior stress history, if you block NMDA receptors pharmacologically during escapable tail shock stress, and look at the ability of rats to learn to escape the stress by performing an action to turn off the shock/stress, under which conditions would you expect rats to fail to perform this escape behavior?

none of the above (not if you block NMDA receptors in the dorsolateral striatum, If you block NMDA receptors in the dorsomedial striatum, or If you block NMDA receptors in the dorsal raphe)

In a PET scan study, which of the following brain areas demonstrated a significant increase in opioid receptor availability following endurance running in athletes?

none of the above (not the insula, the orbitofrontal cortex, or the anterior cingulate cortex)

Beta-endorphin binds to which class of receptors?

opioid

Beta-endorphin is a peptide derived from

proopiomelanocortin (POMC)

Which brainstem nucleus has been particularly implicated in stress-induced increases in heart rate?

raphe pallidus

Stress response habituation, specifically HPA axis responses, has been shown to last

several weeks

The authors looked at the expression of Fos in the ______________ , as an indicator of neuronal activation.

spinal cord

In a study of the behavioral control of stress, where tail shock is the stressor, regarding rats in the yoked inescapable stress (IS) group

the amount of tail shock each rat experiences is dependent on the behavioral actions of another rat

This paper provides evidence that

the effect of a male presence on pain expression in mice is dependent on androgens

Which of the following changed the pain response in mice?

the gender of the person present during the pain response, zymosan A, and formalin (not AM-251)

Which of the following is true for female rats?

they have a neural pathway that projects from prefrontal cortex to the dorsal raphe nucleus, but do not recruit/activate this neural pathway during escapable stress

In a stress habituation study by Grissom and Bhatnaghar, rats were restrained in different contexts to determine if the context in which the habituated stimulus (restraint) was experienced, altered the degree of response (ACTH) habituation. How did the researchers alter the context in which restraint was experienced?

they used different odors, such as the room odor, banana or peppermint

Imagine you are using a radioactive tracer that crosses the blood brain barrier and binds to postsynaptic receptors for "neurotransmitter X" in a PET scan study. After 2 hours of intense exercise in trained individuals, you see a significant reduction of tracer binding in the participants' cingulate cortex compared to baseline conditions.Which of the following is/are true?

this is evidence that intense exercise increases the release of "neurotransmitter X" in the cingulate cortex

True or False? 6 weeks of voluntary wheel running in rats reduces the number of serotonin neurons in the dorsal raphe nucleus (DRN) that express Fos in response to inescapable tail shock stress (IS), relative to sedentary rats exposed to IS

true

True or False? Exercise interventions have been shown to be effective in relieving symptoms of depression in clinical populations.

true

True or False? Experimental evidence suggests that wheel running in rats is rewarding.

true

True or False? Habituation is considered to be a form of learning.

true

True or False? Having behavioral control over a stressor is considered to be an active coping response

true

True or False? Having control over a stressor can change responses to subsequent stressors.

true

True or False? High anxiety sensitivity has been associated with poorer response habituation to acoustic startle stimuli, relative to low anxiety sensitivity.

true

True or False? If you wanted to activate neurons in a region of the cortex, you could inject picrotoxin into that region.

true

True or False? If you wanted to inhibit neurons in a particular brain region, you could inject muscimol into that region.

true

True or False? If you wanted to stimulate (activate) neurons in a particular brain region, you could inject a benzodiazepine inverse agonist into that region.

true

True or False? In experiments performed by Steve Maier's group, looking at behavioral control over stress, rats in the inescapable tail shock stress (IS) group receive the same amount of physical stressor exposure as the rats in the escapable tail shock stress (ES) group.

true

True or False? In rats that have had access to a running wheel in their home cage for 6 weeks, and relative to sedentary controls, exposure to low to moderate intensity noise stress results in less activation (measured with Fos expression) in many stress-related brain regions, including the paraventricular nucleus of the hypothalamus (PVN)

true

True or False? In rats, 6 weeks of voluntary wheel running leads to a decrease in HPA axis responses to mild but not intense stressor exposure, relative to the responses observed in sedentary rats.

true

True or False? In rats, 6 weeks of wheel running most likely produces stress resilience because of long term neuroplastic changes in the brain.

true

True or False? In rats, if the raphe pallidus is inactivated, the acute stress-induced increases in heart rate are reduced.

true

True or False? Inescapable tail shock stress (IS) in rats is thought to lead to sensitization of serotonin neurons in the dorsal raphe nucleus (DRN)

true

True or False? Inescapable tail shock stress (IS) leads to an increase in basal levels of serotonin in the basolateral amygdala 24 h later.

true

True or False? It takes more than 3 weeks of voluntary wheel running in rats to see a reduction in the HPA axis responses to mild stressor exposure, relative to the response in sedentary rats.

true

True or False? It takes more than 3 weeks of voluntary wheel running in rats to see a reduction in the escape deficits produced by inescapable tail shock stress (IS), relative to the response in sedentary rats.

true

True or False? Just like people, animals can show learned helpless behavior after experience of an uncontrollable stressor.

true

True or False? Nyhuis et al. showed that if a rat is familiar with an environment, the rat will show habituated HPA axis responses to an 8th noise stress exposure regardless of whether the rat had experienced noise stress in that environment before, suggesting that stress habituation may NOT be context specific.

true

True or False? One way in which stress resilience could be manifested, is if a person has a lower cortisol response to a stressor than would normally be expected.

true

True or False? Some studies have shown that anxiety in people is associated with poor response habituation.

true

True or False? The authors provide evidence consistent with the hypothesis that glucocorticoids are necessary for the epigenetic modifications in dopamine neurons in GXE mice

true

True or False? To show that a brain region is sufficient to elicit a certain response, for example, a particular behavior, you should stimulate/activate neurons in that brain region.

true

True or false? A positive correlation between positive affect and running-induced plasma anandamide has been demonstrated in humans.

true

True or false? In male rats, if you activate the rat ventromedial prefrontal cortex (vmPFC), prior to inescapable tail shock stress (IS) exposure, you would expect to see an increase in social exploration of a juvenile relative to IS animals that do not have their vmPFC activated.

true

True or false? In male rats, the ventromedial prefrontal cortex (vmPFC) is thought to prevent sensitization of serotonin neurons in the dorsal raphe nucleus (DRN) during intense, but escapable, stress.

true

True or false? Inactivation of the anterior part of the posterior hypothalamus reduces the acute HPA axis response to noise stress in rats.

true

True or false? Inactivation of the ventromedial prefrontal cortex (vmPFC) prior to escapable tail shock stress (ES) results in a behavioral pattern more like that observed following inescapable tail shock stress (IS) in male rats.

true

True or false? Rats were given a muscimol injection into the anterior part of the posterior hypothalamus on three successive days, prior to noise stress exposure. Compared to vehicle injected rats that also received 3 noise stress exposures, the muscimol treated rats showed poorer HPA axis response habituation to noise stress on a subsequent drug free test day, indicating the importance of the posterior hypothalamus in HPA axis response habituation.

true

True or false? Stimulation of the rat ventromedial prefrontal cortex (vmPFC) indirectly inhibits serotonin neurons of the dorsal raphe nucleus (DRN).

true

True or false? The shuttle box escape test is used to demonstrate learned helpless behavior in rats.

true

True or false? When an individual chooses actions that lead to a desired outcome, this leads to the perception of control.

true

In aplysia, habituation has been studied by looking at the

(B and C) siphon withdrawal reflex AND gill withdrawal reflex

Which of the following would likely cause a "runner's high"

(playing with kids at the park hehe jk) intense exercise for 2 hours

What is habituation to a stressful stimulus?

A decrease in a stressor-elicited response resulting from the repeated presentation of the same stressor

In Figure 4A, you can see green and red beads and TH expression. Which of the following statements are true for this figure?

Both the red and green beads were transported in a retrograde direction to the ventral tegmental area

In male rats with no prior stress history, if you block NMDA receptors pharmacologically during escapable tail shock stress, and look at social exploration of a juvenile rat 24 hours later, under which conditions would you expect the social exploration to be lowest?

If you block NMDA receptors in the dorsomedial striatum

Which of the following is true regarding coping and behavioral control?

babies as young as 4 months show negative emotional responses to a loss of control

Which of the following is an opioid receptor antagonist?

Naloxone (not AM-251 or androstenone)

Which of the following techniques would be most suitable to determine if release of endogenous opioids in the brain is associated with a "runner's high"

PET scan

The authors found that

The decrease in pain observed when a male was in the room was dependent on release of both opioids and endocannabinoids.

Which of the following is/are true?

The gene that codes for tyrosine hydroxylase contains a glucocorticoid response element (GRE), and so is susceptible to transcriptional regulation by glucocorticoids.

A benzodiazepine inverse agonist

binds to a site on a GABA-A receptor (it does not increase the number of chloride ions entering the cell or facilitate the action of GABA)

If endorphins in the brain are necessary for a runner's high, relative to vehicle condition, naloxone (a non-selective opioid receptor antagonist that crosses the blood brain barrier) would most likely cause which of the following?

a decrease in euphoria after intense exercise

One group of rats was sedentary for 6 weeks, and another group had free access to a running wheel in its home cage for 6 weeks.The two groups of rats were given 100 inescapable tail shocks, and their response in the shuttle box escape test, and their freezing response to 2 foot shocks were measured 24 hours later. Relative to the sedentary rats, the 6 week run rats would show

a decreased latency to escape in the shuttle box escape test

Which of the following is/are true regarding IS (inescapable tail shock stress) and ES (escapable tail shock stress) in male rats?

all of the above (IS and ES result in similar levels of ACTH and corticosterone release, lesioning the dorsal raphe nucleus (DRN) prevents the shuttle box escape deficits seen after IS, and in the absence of stress, activation of the DRN with a benzodiazepine inverse agonist results in shuttle box escape deficits similar to those seen after IS)

Which of the following is true regarding beta-endorphin in the blood?

all of the above (Intense exercise increases levels of beta-endorphin in the blood, Beta-endorphin in the blood comes mainly from the pituitary gland, and Beta-endorphin in the blood does not cross the blood-brain barrier in significant quantities)

The article describes changes in tyrosine hydroxylase (TH) expression. TH is

all of the above (an enzyme involved in the dopamine synthesis pathway, an enzyme involved in the norepinephrine synthesis pathway, an enzyme involved in the epinephrine synthesis pathway)

In Figures 2 and 3, data from in vivo microdialysis experiments are shown. In vivo microdialysis is a method that....

all of the above (can be used to measure small molecules such as amine neurotransmitters in the brain, can be used in awake animals performing a relevant behvavioral task, and is based on the principle of molecules moving across a dialysis membrane according to a concentration gradient)

In female rats, and compared to a home cage control, escapable stress results in

all of the above (decreased social exploration of a juvenile rat 24h later, increased escape latency (learned helplessness) in the shuttle box escape test 24h later, and increased freezing behavior (fear) after mild foot shock 24h later)

In female rats, and compared to a home cage control, inescapable stress results in

all of the above (decreased social exploration of a juvenile rat 24h later, increased escape latency (learned helplessness) in the shuttle box escape test 24h later, and increased freezing behavior (fear) after mild foot shock 24h later)

Which of the following is true of the dorsal raphe nucleus (DRN)?

all of the above (it contains serotonin neurons, it contains GABA neurons, and it is in the brainstem)

A student finds giving a presentation to the class stressful. If this student gives the same presentation to the same class 10 times during successive class periods, compared to the first presentation, after the tenth presentation you would expect this student's

all of the above (plasma cortisol levels to be lower, plasma epinephrine levels to be lower, and heart rate to be lower)

Which of the following are associated with stress resilience?

all of the above (positive emotions. cognitive flexibility, spirituality, and social support)

Which of the following brain regions have been implicated to play a role in modulation of habituated stress responses?

all of the above (prefrontal cortex, basolateral amygdala, paraventricular nucleus of the thalamus, and the posterior hypothalamus)

Which of the following characterize the psychological state of learned helplessness in people?

all of the above (reduced motivation, difficulty in determining causality, and depressed mood)

Muscimol is often used to inactivate a specific brain region. It works as

an agonist at GABA-A receptors

Picrotoxin acts as

an antagonist at GABA-A receptors

You present 100 dB white noise to a rat for 30 min. and find that it causes an increased release of ACTH and corticosterone. You do the same thing every day for a week. After the 7th noise exposure you find that the plasma ACTH and corticosterone levels are the same as basal values, as if the animal has not been exposed to a stressor at all. You put the rat back in its home cage, and don't do anything else for 3 weeks. You then expose it to restraint stress. In response to this restraint stress presentation, you would expect to see

an increase in ACTH and corticosterone, with a magnitude at least as big as following restraint stress with no prior stress history

In the forced swim test, an increase in immobility time is generally interpreted as

an increase in behavioral despair

In the GXE group, and compared to controls, the authors observed

an increase in dopamine D2 receptor expression in the frontal cortex

Eric Kandel won a Nobel prize for his work on learning (for example response habituation) in

aplysia

In Figure 4B the authors look at methylation of CpG sites. CpG sites

are important for transcriptional regulation of a gene

When muscimol binds to GABAA receptors on a neuron, it causes

chloride ions to enter the neuron

Which test would be most suitable to determine if wheel running is rewarding in rats?

conditioned place preference

Which of the following is/are true for the GXE group, compared with control mice?

corticosterone levels were higher after the behavioral tests employed by the researchers

According to the authors' data, the presence of a human male during expression of pain in mice resulted in a

decrease in the mouse grimace score

Inescapable tail shock stress (IS) has been shown to sensitize neurons of the __________, which is thought to result in the various behavioral consequences of inescapable stress, such as learned helpless behavior.

dorsal raphe

You think that brain region A might be important in modulating responses controlled by brain regions B and C. In order to show that brain region A projects to both brain region B AND brain region C, you could

either B or C (inject a retrograde tracer in region B and a different retrograde tracer in region C OR inject an anterograde tracer in region A)