Dreams-Scientific advances in the twentieth century

[CHUNX638]

Scientific advances in the twentieth century have allowed researchers to study the chemical activities taking place in the sleeping human brain. In the 1970s, researcher Barry Jacobs drew on these advances to propose that a shared neurochemical basis in the neurotransmitters serotonin and norepinephrine accounts for the observable similarities between dreams and hallucinations. To test Jacobs’ theory, researchers attempted to elucidate the role of serotonin and norepinephrine in the normal sleep cycle and the effect of hallucinogenic drugs on these neurotransmitters.

Serotonin appears important for managing sleep, mood, and appetite, among other functions, while norepinephrine facilitates alertness and mental focus. Both neurotransmitters are discharged in high quantities only during waking states. At the onset of sleep, the neurons that release these neurotransmitters become less active, allowing the brain to enter the three non-rapid eye movement (non-REM) stages of sleep. The non-REM stages typically are not associated with normal dreaming, though parasomnias, such as sleepwalking and confusional arousals, are most common during stage 3. When the brain is ready to enter the fourth stage, REM, which is strongly associated with dreaming, the levels of these two chemicals drop virtually to zero. The Jacobs hypothesis held that the absence of norepinephrine was required to enable the brain to remain asleep, while the absence of serotonin was necessary to allow dreaming to occur.

Lysergic acid diethylamide, or LSD, is a semi-synthetic psychedelic drug which causes significant alteration of the senses; at doses higher than 20 micrograms, it can have a hallucinogenic effect. LSD mimics serotonin well enough to be able to bind at most of the neurotransmitter’s receptor sites, largely inhibiting normal transmission. In addition, the drug causes the Locus coeruleus, a cluster of neurons containing norepinephrine, to greatly accelerate activity. If the drug stimulates norepinephrine, thereby precluding sleep, and inhibits serotonin, creating a necessary condition for dreaming, then the resulting hallucinations could merely be “dreaming while awake.” The research thus far is promising but inconclusive; future scientific advances should allow this theory to be tested more rigorously.

01 Which of the following, if true, would most undermine the central premise of the Jacobs hypothesis?
A LSD does not cause as much long-term neurological damage as previously thought.
B Serotonin and norepinephrine are found to rise and fall in tandem.
C Researchers prove conclusively that the level of norepinephrine in the brain is a significant factor in enabling the brain to sleep.
D Some semi-synthetic hallucinogenic drugs other than LSD do not inhibit serotonin.
E The first three stages of sleep are as crucial to the process of dreaming as the fourth stage.

I want to know if it's the correct process when I doing this question.
I combine the paragraph 2 and 3 to work out this quesion.
"the absence of serotonin was necessary to allow dreaming to occur" and " and inhibits serotonin, creating a necessary condition for dreaming".

And I think this question is too difficult to solve, because I need to read the two paragraph , isn't right?
Or if I did wrong process?

02 According to the passage, each of the following is true EXCEPT
A Norepinephrine and serotonin are discharged only during waking states.
B Ingesting more than 20 micrograms of LSD will cause some people to hallucinate.
C Rapid eye movement is the stage of sleep during which people typically dream.
D LSD causes neurons to increase the rate at which they discharge norepinephrine.
E The absence of serotonin seems to be necessary in order to enable the brain to dream.

I can ensure A choice is the correct answer. In this situation, can I just choose A and move on? Can I just ignore all the other choices?

Please help me. Thank you very much!

[Sage Pearce-Higgins]

Which of the following, if true, would most undermine the central premise of the Jacobs hypothesis?
A LSD does not cause as much long-term neurological damage as previously thought.
B Serotonin and norepinephrine are found to rise and fall in tandem.
C Researchers prove conclusively that the level of norepinephrine in the brain is a significant factor in enabling the brain to sleep.
D Some semi-synthetic hallucinogenic drugs other than LSD do not inhibit serotonin.
E The first three stages of sleep are as crucial to the process of dreaming as the fourth stage.

I want to know if it's the correct process when I doing this question.
I combine the paragraph 2 and 3 to work out this quesion.
"the absence of serotonin was necessary to allow dreaming to occur" and " and inhibits serotonin, creating a necessary condition for dreaming".

And I think this question is too difficult to solve, because I need to read the two paragraph , isn't right?
Or if I did wrong process?

On a philosophical note, there's no such thing as a "wrong" process. Sure, I may sound a bit fussy - there is such a thing as an ineffective process and that's probably what you mean. However, trying to get the "right" process may be counterproductive; I encourage you to work on understanding, not pleasing the teacher. I'll try to show you an effective way.

I know that the answer choices can be confusing, so I always start by just reading the passage to understand what it's about. Next, the question mentions 'Jacob's hypothesis'. Let's be clear about what that is from the second paragraph: The Jacobs hypothesis held that the absence of norepinephrine was required to enable the brain to remain asleep, while the absence of serotonin was necessary to allow dreaming to occur. Note how Jacob claims that these conditions are necessary - she is saying that they have to occur for hallucination to take place. What would disprove this is if we found hallucination without these conditions, i.e. answer choice D. I'll leave you to consider how to eliminate the other answer choices. Sure, this is a hard problem, in the 700-800 range.

According to the passage, each of the following is true EXCEPT
A Norepinephrine and serotonin are discharged only during waking states.
B Ingesting more than 20 micrograms of LSD will cause some people to hallucinate.
C Rapid eye movement is the stage of sleep during which people typically dream.
D LSD causes neurons to increase the rate at which they discharge norepinephrine.
E The absence of serotonin seems to be necessary in order to enable the brain to dream.

I can ensure A choice is the correct answer. In this situation, can I just choose A and move on? Can I just ignore all the other choices?

For me, that represents a risky strategy. Even if I'm pretty certain that the answer is A, I'd read the other answer choices to check if I missed something. The only time I wouldn't do this is if I was very short of time.