GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 22 Oct 2019, 09:44

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

REM (rapid eye movement) sleep, also called "paradoxical" sleep

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Find Similar Topics 
Tuck School Moderator
User avatar
P
Status: Valar Dohaeris
Joined: 31 Aug 2016
Posts: 301
GMAT 1: 700 Q49 V37
Reviews Badge
REM (rapid eye movement) sleep, also called "paradoxical" sleep  [#permalink]

Show Tags

New post Updated on: 04 Sep 2019, 01:58
2
3
Question 1
00:00
A
B
C
D
E

based on 113 sessions

28% (02:58) correct 72% (03:20) wrong

HideShow timer Statistics

Question 2
00:00
A
B
C
D
E

based on 135 sessions

36% (01:33) correct 64% (01:18) wrong

HideShow timer Statistics

Question 3
00:00
A
B
C
D
E

based on 125 sessions

47% (01:25) correct 53% (01:28) wrong

HideShow timer Statistics

Question 4
00:00
A
B
C
D
E

based on 108 sessions

47% (01:39) correct 53% (01:40) wrong

HideShow timer Statistics

New Project RC Butler 2019 - Practice 2 RC Passages Everyday
Passage # 201, Date : 12-Jul-2019
This post is a part of New Project RC Butler 2019. Click here for Details


REM (rapid eye movement) sleep, also called "paradoxical" sleep because of its neurologically aroused character, is best known as the sleep phase during which intense dreams occur in humans. It has been found to have a surprisingly close relationship with the waking state. The electroencephalogram (EEG), which records general electrical activity in the brain, indicates that REM sleep displays high-frequency, low-amplitude waves all but identical to those of wakefulness. This is in contrast to the slow-wave (low-frequency, high-amplitude) patterns of dreamless sleep. Additionally, neurological activity in various subunits of the brain is essentially similar in both REM sleep and the awakened state. Especially revealing is a pattern of waves in a part of the cerebral cortex called the hippocampus. This "theta rhythm" is manifested regularly throughout both REM sleep and wakefulness, and it contrasts with the irregular activity of the hippocampus during slow-wave sleep. Measurements of brain temperature indicated a third similarity: brain temperature decreases slightly during slow-wave sleep, then rises in REM sleep to about the same level as in wakefulness.

A recent, accidental discovery substantially augmented our understanding of the connection. PGO spikes (short-lived, high-amplitude electrical waves observed mo frequently in the pons, a region in the brain stem) were thought to occur almost uniquely in REM sleep and to occur spontaneously, without external stimulus. However, when a laboratory worker accidentally struck an EEG recording cage while a cat's slow-wave sleep was being traced, a PGO spike appeared in the record almost instantly. A subsequent study indicated that both sounds and touch could easily produce PGO spikes in either REM or slow-wave sleep. Far from being spontaneous and unique to REM sleep, PGO spikes seem to be general alerting responses occurring in several slow sleep phases.

This finding in tum has prompted a reevaluation of waves called eye-movement potentials (EMPs), which occur in the waking state. These were believed to depend on environmental levels of light, but in the EEG record, they appeared identical to PGO spikes. Reasoning that a cat in a darkened cage might be bored, a worker directed the odor of tuna fish through the cage and presently observed EMPs identical to PGO spikes. Sharp noises produced the same result. Both PGO spikes and eye movement potentials are now seen as varieties of a general alerting response, which can be stimulated during REM sleep, slow-wave sleep, and wakefulness. The author is primarily concerned with 0 proving that brain wave activity occurs during REM sleep 0 studying the functions of brain subunits during various sleep phases exploring inconsistencies in current accounts of brain-wave activity in various mind states 0 establishing that most sleep states involve patterns of electrical activity o demonstrating the neurologically amused character of various stages of consciousness

1. The author is primarily concerned with

A) proving that brain wave activity occurs during REM sleep
B) studying the functions of brain subunits during various sleep phases
C) exploring inconsistencies in current accounts of brain-wave activity in various mind states
D) establishing that most sleep states involve patterns of electrical activity
E) demonstrating the neurologically aroused character of various stages of consciousness

2. According to the passage, which of the following is true of both wakefulness and REM sleep?

A) Slow-wave patterns predominate.
B) Brain temperature tends to drop.
C) Sensory contact with the environment is intensified.
D) Low-amplitude waves can be observed in the pens.
E) Brain wave patterns vary in response to environmental stimuli.

3. It can be inferred that the odor of tuna fish was directed through a darkened cage in order to determine which of the following?

A) Do eye movement potentials occur in REM sleep?
B) Can occur as a response to stimuli other than environmental levels of light?
C) Are EMPs identical to PGO spikes?
D) Are relaxed animals as neurologically alert as excited animals?
E) Do EMPs occur only in response to external stimuli?

4. The author implies that eye-movement potentials, which appear identical to PGO spikes in the EEG, were reevaluated because

A)PGO spikes were discovered to be responses to specific external stimulation
B)both responses appeared randomly and spontaneously in the EEG .
C)EMPs had been thought to occur in the absence of external stimuli
D)both responses occurred only in REM sleep
E)neither response occurred during slow-wave sleep


_________________

Originally posted by LordStark on 13 Feb 2019, 02:56.
Last edited by SajjadAhmad on 04 Sep 2019, 01:58, edited 1 time in total.
Updated - Complete topic (402).
Manager
Manager
avatar
B
Joined: 29 Nov 2016
Posts: 163
Location: India
GMAT 1: 750 Q50 V42
Re: REM (rapid eye movement) sleep, also called "paradoxical" sleep  [#permalink]

Show Tags

New post 08 Jul 2019, 22:59
LordStark can you provide the OE and POE to Q4.

I think that the finding that PGO SPIKE occurs in low wave as response to the Cat's EEG triggered them to study EMP as sell. The finding was contradictory in case of PGO in a way that it occurred both in REM and Low wave sleep. It prompted the scientists to study another factor EMP which also later showed to be relevant to all 3 stages, just as PGO did.

Please help.
Intern
Intern
avatar
B
Joined: 19 Mar 2017
Posts: 1
Re: REM (rapid eye movement) sleep, also called "paradoxical" sleep  [#permalink]

Show Tags

New post 12 Jul 2019, 16:22
2
Sharing my analysis of Q4.


Quote:
4. The author implies that eye-movement potentials (EMPs), which appear identical to PGO spikes in the EEG, were reevaluated because


The question is asking us to identify the cause of the reevaluation of the EMPs. EMPs are mentioned for the first time in the first sentence of the last paragraph. The paragraph starts with "This finding in turn has prompted a reevaluation of ... (EMPs) ...". This finding refers to something that has already been mentioned earlier, implying the actual cause was described in the first or the second paragraph.


Answer choices:

Quote:
A) PGO spikes were discovered to be responses to specific external stimulation



Second paragraph says that "PGO ... were thought to occur ... spontaneously", but an accident and a subsequent study found that PGO spikes are neither spontaneous nor unique to REM: "PGO spikes seem to be general alerting responses occurring in several slow sleep phases." This could be the finding referred in the first sentence introducing EMPs. Mark this as a potential answer.

Quote:
B) Both responses appeared randomly and spontaneously in the EEG



The passage says EMPs are not random and spontaneous but "... believed to depend on environmental levels of light". Cross off this answer choice.

Quote:
C) EMPs had been thought to occur in the absence of external stimuli



Similar to the answer choice B), EMPs were "... believed to depend on environmental levels of light". Light is an example of an external (to the body) stimulus. Cross off this answer.

Quote:
D) Both responses occurred only in REM sleep



The third paragraph says EMPs occur in the waking state. Cross off.

Quote:
E) Neither response occurred during slow-wave sleep



The last sentence in the second paragraph says "PGO spikes seem to be general alerting responses occurring in several slow sleep phases.". Cross it off.

The only answer choice left is A.
Intern
Intern
avatar
B
Joined: 21 Feb 2019
Posts: 22
Re: REM (rapid eye movement) sleep, also called "paradoxical" sleep  [#permalink]

Show Tags

New post 04 Sep 2019, 01:47
GMATNinja, GMATNinjaTwo - Hi could you explain this one line - The electroencephalogram (EEG), which records general electrical activity in the brain, indicates that REM sleep displays high-frequency, low-amplitude waves all but identical to those of wakefulness.
GMAT Club Bot
Re: REM (rapid eye movement) sleep, also called "paradoxical" sleep   [#permalink] 04 Sep 2019, 01:47
Display posts from previous: Sort by

REM (rapid eye movement) sleep, also called "paradoxical" sleep

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne