MCAT Psychology and Sociology Practice Test 3: interacting with the environment

Guided meditation and deep-breathing exercises have long been used as effective techniques for stress reduction. The mechanism of action for this non-pharmacologic intervention is not entirely known, but scientists believe that the act of focusing ones thoughts and deep belly-breathing both serve to somehow inhibit the stress response activated by the hypothalamic-pituitary-adrenal axis. Practitioners of meditation are capable of reducing their heart and respiration rates seemingly on command.

Irritable Bowel Syndrome (IBS) is a disorder that causes a range of abdominal discomfort and bowel irregularities, but unlike bowel diseases with similar symptoms, there are no physical abnormalities; rather, the disorder appears to be the physical manifestation of psychological triggers. For example, IBS is often comorbid with anxiety disorders or episodes of extreme stress. Acute anxiety and stress are known triggers for IBS symptoms, which usually include severe abdominal cramping, bloating, gassiness, constipation and/or diarrhea (sometimes sufferers experience one or the other more frequently, and a minority of sufferers experience both in an alternating pattern). IBS symptoms usually begin during late teen or early adult years, and a majority of sufferers are women.

The current standard non-pharmacologic treatment for IBS is cognitive behavior therapy (CBT). CBT treats IBS sufferers by treating the emotional and psychological triggers that cause physical symptoms. A trained therapist uses a structured, goal-oriented plan to identify thought patterns and behaviors that trigger IBS symptoms, and provides patients with very specific tools for recognizing these, and implementing techniques to replace these negative thoughts and behaviors with more positive ones.

In an attempt to determine if meditation is as beneficial as CBT for treating IBS, a recent six-month study was conducted on female IBS sufferers. Eligible participants had active IBS symptoms for at least three months during the past year. Participants with and without a diagnosed anxiety disorder were recruited to participate in this study. Subjects were randomly assigned to one of three groups: a CBT group, a guided-meditation group, and a no-treatment group. Approximately 65% of the participants had an anxiety disorder, and these subjects were roughly equally represented in each of the three groups. The results of this study, measured by percent reduction of IBS symptoms after treatment, are summarized in Figure 1.

Figure 1 IBS symptom reduction for participants with and without anxiety disorders, by treatment condition

1. Based on the results of this study, what can be most reasonably concluded about the efficacy of CBT for IBS sufferers who do not have an anxiety disorder?

• A. CBT is more effective than no treatment and more effective than meditation.
• B. CBT and meditation combined provide the most effective treatment possible.
• C. CBT is not as effective as meditation.
• D. CBT is equally effective for IBS sufferers with and without anxiety disorders.

2. What is the role of the adrenal gland in the stress response?

• A. The adrenal gland produces epinephrine and norepinephrine as part of the parasympathetic response to stressful triggers.
• B. At the onset of a stressful event, the adrenal gland triggers a cascade of events in the hypothalamus and pituitary, resulting in activation of the sympathetic nervous system's "fight or flight" response.
• C. The adrenal medulla produces cortisol, which helps regulate blood pressure and heart rate, in response to stress.
• D. The adrenal medulla produces adrenaline in response to acute stressors and the adrenal cortex produces cortisol in response to longer-term, low-grade stressors.

3. The average individual diagnosed with IBS is a 40-50 year old female who is white, educated, married, and middle to upper-middle class. Based on this information, what might you conclude about IBS?

• A. IBS is underdiagnosed in less-affluent populations.
• B. IBS rarely affects younger men and women.
• C. There is a causal relationship between education status and IBS.
• D. Age, gender, race, and marital status should all be viewed as risk factors for developing IBS.

4. Given the description of the study in this passage, which unknown factor might have the most influence on the validity of the results?

• A. Sample size
• B. Duration of IBS symptoms before entering the study
• C. Participants' previous exposure to medication to treat IBS symptoms
• D. Length of the treatment protocols

5. Suppose that a recent study, using advanced neuroimaging techniques, found increased activity in the anterior cingulate cortex during meditation. Given the types of physical responses to meditation described in the passage, what functions are likely associated with this area of the brain?

• A. Sympathetic functions, including inhibition of the hypothalamus to prevent release of corticotropin releasing hormone (CRH)
• B. Somatic functions, including control of the diaphragm
• C. Autonomic functions, including heart rate and blood pressure
• D. Rational cognitive functions, including decision-making

6. Which of the following represents a stressor that would be considered a "catastrophe?"

I. A terrorist attack that kills hundreds of people

II. Divorce

III. Death of a child

• A. I only
• B. III only
• C. I and III
• D. I, II, and III