Thanks for bringing this up - you know, I think there's a lot to be taken from the way that you phrased:
after 10 pages or so I'm just not able to take in any more information.
The bad news here - I think you're going about this the wrong way - is the good news, too: the GMAT is a test that must be
practiced much more than it must be "
studied for".
And if you're "doing" rather than "absorbing", you should find that time moves more quickly and it's easier to stay engaged and focused. You really shouldn't be poring over 10 pages of a prep book all at once - you should find a few strategies and then see how they work in on real questions, using practice questions from your prep books or the OG. You should pay attention to the incorrect answers and how they're created to try to trap you; you should propose your own tweaks to questions to see if you can think like the testmaker to make them more difficult (what if it was "less than" and not "greater than"? What if the word "only" was in the conclusion?).
The GMAT is absolutely not a content-based test; it is not testing what you know. It's a reasoning test - it tests how you think. So to study effectively you need to employ practice questions and self-analysis of how you did. You need to think about the logic behind the problems; you mentioned you're studying a Sentence Correction book - when you see an incorrect verb tense used, don't simply think "present tense - past-progressive tense...this is wrong", but ask yourself "why is this an illogical meaning? Why don't these verbs give a valid timeline?". You'll find that these questions almost always test logic before they test hard-core mechanical knowledge, and logic is stickier in the mind...you can train yourself much easier to think logically and critically than you can to master all kinds of obscure grammatical subtleties.
So if you're struggling with concentration, I'd just recenter your focus on DOING more than on READING. Think a lot more, memorize a lot less, and try to embrace the logical challenge within each problem and you'll find that it's much more fun and memorable to study that way.
Brian Galvin
GMAT Instructor
Chief Academic Officer
Veritas Prep
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