Jim brings up a VERY important part of the test taking -- one that we've (TPNY) has brought to the forefront of our GMAT training.
If you mentally/emotionally/physically fortify yourself, and get into the proper, most effective mindset, you've not only trained yourself mentally, but for the 'inner game' of test taking. MOST people do not do better with the anxiety of the GMAT. They did better when they were younger, in highschool and college but by the time a student takes the GMAT, other factors get involved and the anxiety and mental roadblocks need to be dealt with.
There are a variety of ways to do this, an I have begun to write about this in other answers.
You'll want to look at how you've responded in the past to prior tests, and if there is any iota of nervousness - - do something about it. The brain cannot tell the difference between a small ammount of anxiety and excitement, however, once it passes a certain threshold: watch out. Further, based on the studies of Skinner, anxiety tends to increase when we repeat the activites/tasks that induce anxiety...it is out of our control - - it takes place in the unconcious mind. This is why GMAT test takers are often a lot more nervous than they were in college or highschool when taking tests. It's not something that comes specifically with 'age'...its a natural progression of test taking and the germination of a behavior patter that no longer works, however the the unconscious mind didn't get the 'memo.'
If you're interested in one psychological study we use as a resource to support this, see
https://psychclassics.yorku.ca/Skinner/Pigeon/
If you have specific issues (anyone who is reading this), feel free to start a new topic for me to address.
