NB F3 S1 Reticular Formation

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NB F3 S1 Reticular Formation

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pearljam59
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03/23/06 - 08:56 AM

An acute extensive bilateral lesion in the reticular formation of the tegmentum of the midbrain is most likely to result in which of the following?

A. Insomnia
B. Intractable pain
C. Loss of consciousness
D. Narcolepsy
E. Rapid eye movements

shocked

babli
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03/23/06 - 10:23 AM

vanshita
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03/23/06 - 04:03 PM

vamsi2004
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07/04/06 - 12:23 PM

waqastariq

07/04/06 - 01:55 PM

loss of conciousneess..definitely smiling face

waqastariq

07/04/06 - 01:55 PM

option C

vamsi2004
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08/04/06 - 11:43 PM

can somone plz explain why option c is ans...

Dr.Papez
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08/05/06 - 11:46 AM

If some has unconsciousnes-there are 2 possible localisations:
1. Bilateral hemisphere dysfucntion
2. Midbrain reticular (RAS) system dysfucntion

vamsi2004
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08/05/06 - 08:09 PM

thanku Dr.papez. ur explanations r always perfect.

Dr.Papez
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08/05/06 - 09:14 PM

#10

Thanks

Dr.Papez
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08/06/06 - 08:41 AM

#11

I check this site only to sharpen my neuroanatomy knowledge. I rarely respond to any other topics.

vamsi2004
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08/06/06 - 09:00 AM

#12

ya i know that (from ur name in th forum)

tringtring
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08/24/06 - 09:51 AM

#13

klimt
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09/30/06 - 11:29 AM

#14

C

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young_doc
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09/30/06 - 04:40 PM

#15

I guess A.

The midbrain reticular formation sends cholinergic projections to the basal ganglia as well as to every nucleus of the thalamus. It extends from the Pons into the midbrain. This nucleus is also involved in the generation of sleep states.
(http://www.anatomy.dal.ca/Human_Neuroanatomy/hand...)

Hence if bilaterally damaged, can't generate sleep, hence insomnia!

(Let's not confuse Reticular formation, with Reticular Activating System!)

My guess. Anyone else?

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Dr.Papez
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10/01/06 - 11:53 AM

#16

You can wake up some one who is sleeping.
But if midbrain is extensively damaged, you can't wake him up-deep unconsciousness is the result. just the opposite of insomnia- not a drop of wakefulness!

young doc, Can you pl explain the diff between RAS and RF?

drfax
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10/01/06 - 02:13 PM

#17

c

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young_doc
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10/01/06 - 03:46 PM

#18

Dr.Papez wrote:
You can wake up some one who is sleeping.
But if midbrain is extensively damaged, you can't wake him up-deep unconsciousness is the result. just the opposite of insomnia- not a drop of wakefulness!

young doc, Can you pl explain the diff between RAS and RF?

I'm just going by what i found after researching it!!! (check the link in my last post...or just read my quote)

RF is to initiate sleep. RAS is to stay awake/alert.

Again just my guess from looking into to.

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lam79m
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10/01/06 - 04:49 PM

#19

Extensive reticular formation damage = coma. Just think of the clinical consequences

Dr.Papez
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10/01/06 - 11:43 PM

#20

Thanks Young doc. I am just cutting and pasting some phrases from the link provided.

The Ascending Reticular Activating System

In 1949 the concept of the general function of the reticular formation changed overnight with the publication of a pair of papers (Lindsley et al., 1949; Morruzzi and Magoun, 1949) In these papers the authors proposed that there is a diffuse system of ascending fibers arising in the reticular formation that is responsible for control of states of consciousness. They called their system the ascending reticular activating system (the ARAS).

IT FURTHER EMPHASISE THAT

Please Note: The ARAS is a functional concept. The reticular formation is an anatomical structure.
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That clarifies the difference.... rather similarity between ARAS and RF
I stick to C

young_doc
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10/02/06 - 10:26 AM

#21

yes...you are all right!!

"Damage to cells of the Reticular Formation can result in Coma..."

http://www.geocities.com/HotSprings/3468/11-01.ht...

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Dr.Papez
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10/02/06 - 11:35 AM

#22

Okay. Thanks. That solves this problem.
Special thanks for that useful link on RF

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