Impulsivity, caffeine, and proofreading: A test of the Easterbrook hypothesis.

Abstract

Easterbrook's (1959) suggestion that arousal is inversely related to the range of cue utilization has been frequently cited as an explanation for the curvilinear relationship between arousal and performance. There is very little empirical support for this position, however. As a test of the Easterbrook hypothesis, 60 undergraduates who varied in their impulsivity level were given caffeine or placebo and then asked to proofread several passages. Estimates of sensitivity were calculated using signal detection techniques. It was predicted that high arousal would reduce sensitivity to interword errors, which require a broad range of cue utilization, but that the observed levels of arousal would not affect sensitivity to intraword errors, which require a minimal range of cue utilization. A significant crossover interaction between impulsivity and drug for interword errors indicated that caffeine increased the error detection rate of the (less aroused) more impulsive subjects but lowered the error detection rate of the (more aroused) less impulsive subjects. The results of this study support the suggestion that arousal has direct effects on the capacity for simultaneous information processing, independent of its effects on performance speed.

Effect of caffeine on prospective and retrospective duration judgements

“…Caffeine appears to facilitate recall in high impulsives but not low impulsives (Gupta, 1991). This suggests that caffeine should increase duration estimates in the retrospective paradigm, in which recall may be a factor (see also Anderson and Revelle, 1982). However, we did not find an effect on retrospective estimates.…”

Effect of Coffee on the Speed of Subject-Paced Information Processing

“…It seems therefore that the type of task used in the present exper iment perhaps together with the monetary reinforcement for maximal performance induced maximal attention and arousal not only in introverts but in extraverts as well. This explanation would also be in line with more recent studies suggesting not only that the interaction of caffeine with personality-dependent levels of arousal de pends on circadian rhythms of arousal and duration of the test loads, but also that this personality-caffeine interaction may be a rather complex one involving par ticular subscales of extraversión such as impulsivity and sociability [Anderson and Revelle, 1982;Keister and McLaughlin. 1972;Revelle et al, 1980],…”

Caffeine, Mental Health, and Psychiatric Disorders

“…Another possibility is that higher caffeine intake may be a self-medication strategy in some impulsive individuals. Indeed, caffeine facilitates the performance of impulsive individuals and impairs the performance of non-impulsive individuals taking complex cognitive tests in the morning, but not in the evening [113,114].…”