Doubt CR 1

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Doubt CR 1

by aditya8062 » Sun Oct 26, 2014 6:17 am
Scientists have several rival theories on the causes of fibromyalgia, a disorder that causes body-wide chronic pain and fatigue. One leading theory holds that conditions such as depression, anxiety, drug use and serotonin deficiency can aggravate or even cause fibromyalgia by interfering with "stage 4," or "deep sleep." This theory is concerned with the function of neuropeptide substance P, which is released in the spinal cord in response to pain and causes nerve endings around the initiating nerves to also become more sensitive to pain. Normally, this mechanism is "reset" during deep sleep. If pain becomes body-wide, however, and the mechanism can not be reset, this process may run out of control.

The theory above on the cause of fibromyalgia rests on which of the following assumptions?

A) The body has a limited amount of control over neuropeptide substance P.
B) Fibromyalgia is a completely preventable disorder, if only other conditions are recognized and treated before it can develop.
C) Deep sleep is necessary to the healthy functioning of the nervous system.
D) The functions of neuropeptides released by the spinal cord must be better understood before a cure for fibromyalgia can be found.
E) Because the causes of fibromyalgia are linked to depression, the disorder should be treated by mental health professionals.

my concern:i feel A is the assumption here

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by David@VeritasPrep » Mon Nov 03, 2014 7:18 am
This is a question that seems difficult as you are reading the stimulus, but only has one possible answer.

Here is the key text:
One leading theory holds that conditions such as depression, anxiety, drug use and serotonin deficiency can aggravate or even cause fibromyalgia by interfering with "stage 4," or "deep sleep."
So, interfering with deep sleep can aggravate or cause fibromyalgia. How? Well the last three sentences tell us that normally during sleep the nervous system resets itself and clears the nueropeptide P. Without deep sleep the nervous system does not function correctly.

So choice C is the correct answer.

Choice A is not the assumption. What if the body has total control over neuropeptide P.? This does not help if deep sleep is the time when the body controls the substance. The body may normally have total control but not in a person with fibromyalgia. And not in a person who is short on sleep.

You might even say that choice A is a little beyond what is being discussed here since "the body" is a pretty broad category.
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by [email protected] » Tue Nov 04, 2014 11:33 pm
Hi aditya8062,

The content in this CR prompt is certainly more technical/scientific than what you'll find in most CR prompts, but the logic is actually fairly common. We're dealing with a "causal" argument (the idea the X causes Y). I will admit that there is a "quirky" aspect to the wording - you have to deduce what a "healthy" nervous system is or isn't based on the tone of the text.

The causal idea is: conditions such as depression, anxiety, drug use, and serotonin deficiency can CAUSE Fibromyalgia (a condition of body-wide pain and fatigue) by INTERFERING WITH DEEP SLEEP. Neuropeptide substance P is released in response to pain and CAUSES nerve endings to be more sensitive to pain. Normally, the mechanism (for Neuropeptide substance P) is "RESET" during DEEP SLEEP.

Notice the usage of the word "normally"? So what happens when things are NOT normal...? The last sentence tells us that pain becomes body-wide and the process may run out of control.

In real basic terms, this argument is based on the effect of DEEP SLEEP (as it relates to Fibromyalgia) - if you get DEEP SLEEP, then you should not have problems with Fibromyalgia. If you DISRUPT DEEP SLEEP in any way, then that might be why you get Fibromyalgia. Either way, the issue IS about DEEP SLEEP. Answer C gives us an assumption that matches the causal logic.

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