All questions of Day 31 for GMAT Exam

Scientific advances in the latter half of the twentieth century have allowed researchers to study the chemical activities taking place in the human brain during the sleep cycle in more detail. In the 1970s, Jacobs employed these advances to postulate that dreams and hallucinations share a common neurochemical mechanism with respect to the neurotransmitters serotonin and norepinephrine that accounts for the observable similarities between the two states of mind. To test the theory, researchers attempted to elucidate the role of these transmitters in the normal sleep cycle and the effect of hallucinogenic drugs on them.
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, memories and awareness; 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 ceruleus, a cluster of neurons containing norepinephrine, to greatly accelerate activity. If the drug stimulates norepinephrine, thereby precluding sleep, and inhibits serotonin, which Jacobs had postulated was 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.

According to the passage, which of the following is true of the drug lysergic acid diethlyamide?

Western analytical philosophy has contributed two major elements to the theory of the political good. It is unfortunate that the value of the first element, personalism, has been diluted by its close association with the second element, valuational solipsism.
Personalism was developed in response to the belief that nations, states, religions, or any other corporate entity have interests that transcend the interests of the individuals that comprise them. The central tenet of personalism, therefore, is that institutions are good or bad insofar as they are good or bad for the individuals that are affected by them. Institutions are not good, for example, because they preserve the nation’s culture or because they protect the natural world, unless preserving the nation’s culture or protecting the natural world is good for the individual. As a philosophical assumption, personalism is most useful in countering arguments for practices that harm individuals in the name of “the greater good,” or the “society at large.” The personalist credo basically states that when it comes to interests, there are no interests but human interests.
However, an excessive devotion to the theory of personalism may lead one to fall into the trap of valuational solipsism. The word solipsism derives from the Latin for “lone self” and the theory of valuational solipsism takes the isolated individual as the sole judge of value. The problem with this viewpoint is obvious. By using the individual as the measure of the good, valuational solipsism neglects to consider the whole range of social values that are part of the political experience. These values include citizenship, status, and community, none of which can exist without reference to other individuals. Instead, political theories are based entirely on non-social values such as happiness, material welfare, and utility, which are not dependent on interactions with others. Such a view obscures a fundamental quality of the political good.

The primary purpose of the passage is to