I__. - International Military Testing Association

consumed. Within each group, subjects rotated through two caffeine conditions in
a counterbalanced order, drinking two cups of either caffeinated or decaffeinated
coffee with lunch. Caffeine use was prohibited at other times during the study.
RESULTS AND DISCUSSION
Analysis of variance tests indicated no significant differences on MAST
performance as a function of group (protein vs. carbohydrate), caffeine (or its
absence), or the interaction of group and caffeine. Salter and Rock (1989) similarly
found no major group effects due to nutrient type, but did find significant
correlations between the proportion of protein actually consumed and
performance. In Table 1 can be seen the correlations in the current study between
the percent of nutrient consumed and MAST performance. Whereas Salter and
Rock (1989) found a positive correlation for protein, the current study found a
negative correlation for carbohydrate. Previous studies have found both types of
effects (Lieberman et al, 1984). However, consideration of the time factor indicates
that the significant negative correlation occurred even in the morning before
Table 1
Correlations Between Percent of Test Food Consumed
and automated Memory and Search Task (MAST) scores
Time.
- Task Level:
II 000 hrs)
2
(1200 hrs)
3
(1430 hrs)
* p-E.05
** PC.01
*** PC.001
Z-character target
4-character target
6-character target
2-character target
4-character target
6-character target
2character target
4-character target
6-character target
Protein Carbohydrate
/N=l6) /NJ 81
-.28 -.58*
-.36 -.58*
-.38 -.58*
-.03 -.65**
-.07 -.37
-.13 -.66**
-.06 -.79***
-.02 -.x5*
-.I5 -.47*