|MadSci Network: General Biology|
This is a very interesting question. Unfortunately, there are no super-clear answers. Caffeine seems to decrease reaction time (in other words make some reactions faster). Most of the studies I found looked what they call psychomotor performance. Mostly, they looked at things like sorting cards or spotting a particular letter or picture. This incrreases or improve some motor skills. It also seems to increase attention. The Navy Seals (Sea Air Land) team did a study, and it helps them perform better, especially when they are tired, like the middle of the night. Caffeine is able to help some people with attention deficit hyperactivity disorder, especially when they are unable to take other types of medications. One of the things that make studying the effects of caffeine difficult is that when people get used to caffeine and stop taking caffeine (say for an experiment), you are actually seeing the effects of withdrawal from caffeine On the other hand, caffeine makes people who don't take caffeine regular (e.g., they don't drink coffee every morning) jittery and anxious. Despite this, it does appear that caffeine improves motor performance. At least for blood pressure, the story a lot clearer. Caffeine raises blood pressure by a few millimeters mercury, about 4 points for 2-3 cups of coffee. Here are a couple abstracts for this. Your school library or local library should be able to get them. You can also search for additional articles with keywords like caffeine + Motor performance or caffeine + blood pressure. THanks for your excellent question. URL: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi? cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15081447 http://www.ncbi.nlm.nih.gov/entrez/query.fcgi? cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9696955
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