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Lucid dreaming occurs when a person becomes consciously aware of a dream and uses executive decision-making skills to critically analyze the dream environment. Lucid dreamers are thus able to control certain aspects of their dreams, an ability that may occur intentionally, through practice, or unintentionally, usually after having noticed something bizarre or unrealistic in the dream. A lucid dreamer might choose to experience the sensation of flying, explore a custom-designed landscape, carry out a predetermined task, or practice a skill. Estimates suggest that about half the population has had a lucid dream, and about 10%-20% of people are considered frequent lucid dreamers experiencing such dreams regularly (at least once a month) .In one study, researchers asked participants to perform a difficult visuomotor task that involved throwing an object through a small moving target. Participants were organized into three groups, one group of frequent lucid dreamers and two groups of nonlucid dreamers. All three groups attempted the visuomotor task at midday in the research lab, before (pretest) and after (posttest) a single night's sleep at home. Lucid dreamers were asked to only practice the visuomotor task overnight during their lucid dream ("lucid practice" group) . One group of nonlucid dreamers practiced the task in the lab, right after the pretest ("waking practice" group) , and another group of nonlucid dreamers performed the pretest and posttest without practicing between the tests ("no practice" group) . The average improvement of hits (the number of times each participant successfully threw the object through the target) from pretest to posttest for each group is shown in Figure 1.
Figure 1 Median improvement in total hits for each group (Note: The notches represent the 95% confidence interval for the median.) The researchers proposed that a follow-up study be devised and conducted to control for any potential variability in each participant's sleep at home. The researchers suggested using the same study procedure except participants would sleep overnight for five consecutive nights in a sleep lab, where the timing and duration of sleep would be standardized. In order to eliminate any potential "first-night effects" (an initial reduction in sleep quality when sleeping in an unfamiliar environment) , researchers proposed that pretest and posttest measures each be taken before and after the third, fourth, and fifth night's sleep.
-A mechanism for researchers to monitor a dream state would be provided by tracking which of the following?

Question

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Lucid dreaming occurs when a person becomes consciously aware of a dream and uses executive decision-making skills to critically analyze the dream environment. Lucid dreamers are thus able to control certain aspects of their dreams, an ability that may occur intentionally, through practice, or unintentionally, usually after having noticed something bizarre or unrealistic in the dream. A lucid dreamer might choose to experience the sensation of flying, explore a custom-designed landscape, carry out a predetermined task, or practice a skill. Estimates suggest that about half the population has had a lucid dream, and about 10%-20% of people are considered frequent lucid dreamers experiencing such dreams regularly (at least once a month) .In one study, researchers asked participants to perform a difficult visuomotor task that involved throwing an object through a small moving target. Participants were organized into three groups, one group of frequent lucid dreamers and two groups of nonlucid dreamers. All three groups attempted the visuomotor task at midday in the research lab, before (pretest) and after (posttest) a single night's sleep at home. Lucid dreamers were asked to only practice the visuomotor task overnight during their lucid dream ("lucid practice" group) . One group of nonlucid dreamers practiced the task in the lab, right after the pretest ("waking practice" group) , and another group of nonlucid dreamers performed the pretest and posttest without practicing between the tests ("no practice" group) . The average improvement of hits (the number of times each participant successfully threw the object through the target) from pretest to posttest for each group is shown in Figure 1.

Figure 1 Median improvement in total hits for each group (Note: The notches represent the 95% confidence interval for the median.) The researchers proposed that a follow-up study be devised and conducted to control for any potential variability in each participant's sleep at home. The researchers suggested using the same study procedure except participants would sleep overnight for five consecutive nights in a sleep lab, where the timing and duration of sleep would be standardized. In order to eliminate any potential "first-night effects" (an initial reduction in sleep quality when sleeping in an unfamiliar environment) , researchers proposed that pretest and posttest measures each be taken before and after the third, fourth, and fifth night's sleep.
-A mechanism for researchers to monitor a dream state would be provided by tracking which of the following?

Quizplus · Accepted Answer

11ecba2d_0c49_f1c3_a3bf_c1427e2b6313_MD0008_00 Dreaming is most often associated with REM sleep, particularly the visually intense dreams remembered after waking. Also known as paradoxical sleep, REM sleep is characterized by brain activity (measured by electroencephalography [EEG]) that resembles the beta waves seen in an awake, alert state, except there is no muscle tone in the body. This prevents the dreamer from acting out the dream, which could result in injury. The only exceptions to this systemic paralysis are the muscles controlling the eyes and the cardiopulmonary system. Although the body is functionally paralyzed during REM sleep, the eye muscles are very active and cause the characteristic closed-eye movements (ie, rapid eye movements) from which this state derives its name. Therefore, researchers can track closed-eye movements to monitor a dream state. Physiological changes are also characteristic of REM sleep. Cardiovascular and respiratory activities become very regular and gradually decrease, along with temperature, during NREM sleep. During REM sleep, body temperature drops to its lowest point, while cardiovascular and respiratory activities become irregular and increase. (Choice B) EEG measurements showing K-complexes demonstrate the presence of stage 2 sleep. (Choice C) Spikes in the release of growth hormone (GH) coincide with deep sleep stages 3 and 4. (Choice D) Sudden, jerking body movements occur when an individual first falls asleep and enters stage 1 sleep. Educational objective: During NREM sleep, cardiopulmonary activity becomes regular and decreases, along with body temperature. During REM sleep, cardiopulmonary activity becomes irregular and increases, while body temperature drops to its lowest point. REM sleep is also characterized by rapid closed-eye movements, muscle paralysis, and brain activity resembling a waking state.

Passage Lucid Dreaming Occurs When a Person Becomes Consciously Aware of of a Dream