Ej. Schicatano et Td. Blumenthal, THE EFFECTS OF CAFFEINE AND DIRECTED ATTENTION ON ACOUSTIC STARTLE HABITUATION, Pharmacology, biochemistry and behavior, 59(1), 1998, pp. 145-150
The present experiment tested the effects of caffeine on acoustic star
tle habituation during different attention tasks in which subjects eit
her (a) attended to the acoustic startle stimulus (auditory attention;
n = 9) (b) attended to a visual search task during presentation of ac
oustic startle stimuli (visual attention; n = 10), or (c) were given n
o specific instructions during acoustic startle testing (no attention;
n = 9). Startle eyeblink responses were measured after subjects recei
ved either caffeine (1 mg/kg) or placebo. Caffeine significantly delay
ed response habituation in the no attention group and in the auditory
attention group, but had no effect on habituation in the visual attent
ion group. These data show that startle habituation can occur with min
imal attention being directed to the acoustic startle stimulus, and th
at visual attention cancels the effects of caffeine on startle habitua
tion. (C) 1998 Elsevier Science Inc.