Caffeine effects on learning, performance, and anxiety in normal school-age children.
OBJECTIVE
The purpose of this investigation was to study the acute effects of caffeine on learning, performance, and anxiety in normal prepubertal children.


METHODS
Twenty-one children were evaluated in a double-blind, placebo-controlled crossover design. Subjects were studied during four sessions, 1 week apart, under the following conditions: baseline, placebo, 2.5 mg/kg caffeine, and 5.0 mg/kg caffeine. Subjects were randomized to order of placebo and the two dosages of caffeine. Dependent measures included tests of attention, manual dexterity, short-term memory, and processing speed. Anxiety rating scales were also administered. Saliva samples were analyzed for caffeine levels.


RESULTS
Caffeine improved performance on two of four measures of the Test of Variables of Attention and on a test of manual dexterity in the dominant hand. There was a trend toward increased current level of self-reported anxiety after caffeine on a visual analogue measure of anxiety. Children reported feeling significantly less "sluggish" after caffeine ingestion than after placebo ingestion.


CONCLUSIONS
In a small sample size, there was indication that caffeine enhanced performance on a test of attention and on a motor task. Children also reported feeling less "sluggish" but somewhat more anxious. Because caffeine is so widely available and frequently consumed by children, these results are important and need replication.
Bernstein
G A
GA
Department of Psychiatry, University of Minnesota Medical School, Minneapolis 55455.
Carroll
M E
ME
Crosby
R D
RD
Perwien
A R
AR
Go
F S
FS
Benowitz
N L
NL
D001007:Anxiety / Q000139:chemically induced*; D002110:Caffeine / Q000009:adverse effects / Q000032:analysis / Q000494:pharmacology*; D002648:Child; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007858:Learning / Q000187:drug effects*; D011594:Psychometrics; D012463:Saliva / Q000737:chemistry; D013647:Task Performance and Analysis
D002110:Caffeine