My overall conclusion is that acute caffeine gives a short-term boost, BUT chronic caffeine is probably slightly worse than chronic abstinence. So my recommendation would be to never consume caffeine, with occasional short exceptions when it would be valuable (e.g. when taking your SATs).
And the answer to the grandparent’s question seems to be that yes, after a few weeks without caffeine your mental performance will go back to baseline, and probably slightly above.
There’s this:
http://www.ncbi.nlm.nih.gov/pubmed/19777214
http://www.ncbi.nlm.nih.gov/pubmed/19241060
http://www.ncbi.nlm.nih.gov/pubmed/18795265
Thanks, the second link is good. Tl;dr:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2738587/figure/F3/
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2738587/figure/F4/
My overall conclusion is that acute caffeine gives a short-term boost, BUT chronic caffeine is probably slightly worse than chronic abstinence. So my recommendation would be to never consume caffeine, with occasional short exceptions when it would be valuable (e.g. when taking your SATs).
And the answer to the grandparent’s question seems to be that yes, after a few weeks without caffeine your mental performance will go back to baseline, and probably slightly above.