Acute caffeine consumption enhances the executive control of visual attention in habitual consumers

Abstract

a b s t r a c tRecent work suggests that a dose of 200-400 mg caffeine can enhance both vigilance and the executive control of visual attention in individuals with low caffeine consumption profiles. The present study seeks to determine whether individuals with relatively high caffeine consumption profiles would show similar advantages. To this end, we examined the effects of four caffeine doses (0 mg, 100 mg, 200 mg, 400 mg) on low-and high-level visual attention in individuals with high consumption profiles (n = 36), in a double-blind study using a repeated measures design. Results from the Attention Network Test indicated that caffeine enhanced both vigilance and the executive control of visual attention, but only at the highest administered dose (400 mg). We demonstrate that in habitual consumers high doses of caffeine can produce beneficial changes in visual attention. These results carry implications for the theorized interactions between caffeine, adenosine and dopamine in brain regions mediating visual attention.Published by Elsevier Inc.

Caffeine and theanine exert opposite effects on attention under emotional arousal

“…Although it is unknown whether theanine consumption leads to habituation, habitual caffeine consumption results in increased tolerance for its stimulating properties and withdrawal effects upon cessation of intake (James and Rogers 2005). Relevant to the present study, in previous work, caffeine enhanced executive function on the ANT and detection for global errors on a language-based task beginning at 200 mg caffeine in low habitual caffeine consumers and 400 mg caffeine in high habitual caffeine consumers (Brunyé et al 2010a(Brunyé et al , 2010b(Brunyé et al , 2012. Additionally, a global processing bias was evident on the hierarchical shape task after 100 mg caffeine in low habitual caffeine consumers (Mahoney et al 2011).…”

“…However, these doses were sufficient to affect executive function. Caffeine consumption resulted in the expected improvement in executive function (Brunyé et al 2010a(Brunyé et al , 2010b. In contrast, theanine prior to an emotionally arousing experience resulted in decrements in executive function, potentially related to its anxiolytic properties.…”

“…The effects of caffeine on cognitive function have been studied extensively. This research has demonstrated that caffeine reliably enhances vigilance and psychomotor performance (Smith 2011) and may enhance processes that require executive control, including response inhibition (Barry et al 2007), selective visual attention (Brunyé et al 2010a(Brunyé et al , 2010b, and working memory (Addicott and Laurienti 2009). Caffeine and theanine, consumed together, exert similar effects to that of caffeine alone, in that 35-50 mg caffeine and 90-100 mg theanine enhanced mental alertness, task-switching attention, and recognition memory relative to placebo (Einöther et al 2010;Giesbrecht et al 2010;Kelly et al 2008;Owen et al 2008).…”

“…Thus, the objective of the current study was to examine the effects of caffeine and theanine, administered alone and together, on measures of visual attention during a heightened state of emotional arousal. The 2 measures chosen to assess visual attention have been shown to be sensitive to caffeine-induced physiological arousal (Brunyé et al 2010a(Brunyé et al , 2010bMahoney et al 2011). These measures include global versus local processing (Kimchi and Palmer 1982) and higher-versus lower-order visual attention (Fan et al 2002).…”

Attention and Working Memory Task-Load Dependent Activation Increase with Deactivation Decrease after Caffeine Ingestion

“…Brain activity difference and behavioral measure difference between pre-and postcaffeine sessions were not correlated with each other either. No caffeine-induced behavior changes found in this study were consistent with an early study of caffeine in sustained attention (41) and a more recent study (42), although significant beneficial behavioral effects of caffeine were observed in several other studies (43,44). One reason for no behavior change after caffeine might be due to the fact that the amount of caffeine (200 mg) used in this study was not enough to cause observable behavior difference.…”