Noun modifier with a preposition

Question

Can someone help me with breaking down this sentence to understand which noun modifier refer what.

1) Whenever you are conscious,  and perhaps even when you are not ,
> Is  and perhaps even when you are not  a noun modifier?
> Is it modifying  conscious ?

2) multiple computations are going on in your brain,  which maintain and update current answers to some key questions : Is anything new going on? 
> Is the modifier  which maintain and update current answers to some key questions  modifying noun  brain ?
> or is it modifying  multiple computations ?

rahulrm09 · Answer

q1

Noun + noun modifiers can modify the entire preceding clause, the preceding noun entity, or a noun in the middle of the sentence. Modification done by these modifiers is completely driven by the context of the sentence.

in this case the clause 
"Whenever you are conscious, and perhaps even when you are not"

modifies the entire clause

" multiple computations are going on in your brain"

for your q 2

which should ideally modify the brain(the nearest noun) and the verbs used should be maintains and updates.

heyrohit · Answer

Yeah, but it seems like it's modifying computions

EducationAisle · Answer

Hi Rohit, it's not  modifying  anything; it's a dependent clause, although it's used as a parenthetical construct here.

In this case, it is modifying  multiple computations , simply because the verb is  maintain  (and not  maintains ).

rahulrm09 · Answer

how can it be an independent clause when it is not making any sense on its own?
It goes against the very definition of an independent clause.

Also, does it make grammatical sense for which to refer to computations?
the computations maintain and update current answers or the brain does?

EducationAisle · Answer

You are right Rahul! It's a  dependent  clause; have edited my answer above.

As mentioned in my post above, because the verb is  plural  ( maintain ),  which  can only modify something  plural  (in this case,  multiple computations )

rahulrm09 · Answer

Hi Ashish,

does it make logical sense for the computations to maintain and update the answers?

or does it make logical sense for the brain to maintain and update the answers?

Thanks
Rahulkumar Marwal

EducationAisle · Answer

Hi Rahul,  logically  perhaps a case could be made for either of the two, though I am more inclined to believe that  which  should ideally modify  brain . Actual GMAT questions normally don't pose such dilemma.

Your initially question was about what was "which"  grammatically  modifying in the current question. The answer to that question is quite clear though:  computations .

rahulrm09 · Answer

but doesnt 'which' refer to the nearest possible noun that makes logical sense?

EducationAisle · Answer

Hi Rahul, for the most part,  which  refers to the nearest noun that makes  grammatical  sense.

p.s. Our book    EducationAisle Sentence Correction Nirvana    discusses  modifiers concepts of  which  , its application and examples in significant detail. If you or someone is interested, PM me your email-id; I can mail the corresponding section.

Noun modifier with a preposition

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