We found that whilst most studies employing basic testing paradigms show that modafinil intake enhances executive function , only half show improvements in attention and learning and memory , and a few even report impairments in divergent creative thinking .
In contrast , when more complex assessment s are used , modafinil appears to consistently engender enhancement of attention , executive functions , and learning .
Importantly , we did not observe any preponderances for side effects or mood changes .
Modafinil is an FDA -approved eugeroic that directly increases cortical catecholamine levels , indirectly upregulates cerebral serotonin , glutamate , orexin , and histamine levels , and indirectly decreases cerebral gamma-amino-butrytic acid levels .
In addition to its approved use treating excessive somnolence , modafinil is thought to be used widely off-prescription for cognitive enhancement .
However , despite this popularity , there has been little consensus on the extent and nature of the cognitive effects of modafinil in healthy , non-sleep-deprived humans .
Effects of modafinil on working memory processes in humans
Rationale Modafinil is a well-tolerated psychostimulant drug with low addictive potential that is used to treat patients with narcolepsy or attention deficit disorders and to enhance vigilance in sleep-deprived military personal . So far , underst and ing of the cognitive enhancing effects of modafinil and the relevant neurobiological mechanisms are incomplete . Objectives The aim of this study was to investigate the effects of modafinil on working memory processes in humans and how they are related to noradrenergic stimulation of the prefrontal cortex . Methods Sixteen healthy volunteers ( aged 20–29 years ) received either modafinil 200 mg or placebo using a double blind crossover design . Two computerized working memory tasks were administered , a numeric manipulation task that requires short-term maintenance of digit-sequences and different degrees of manipulation as well as delayed matching task that assesses maintenance of visuo-spatial information over varying delay lengths . The battery was supplemented by st and ardized paper pencil tasks of attentional functions . Results Modafinil significantly reduced error rates in the long delay condition of the visuo-spatial task and in the manipulation conditions , but not in the maintenance condition of the numeric task . Analyses of reaction times showed no speed-accuracy trade-off . Attentional control tasks ( letter cancellation , trail-making , catch trials ) were not affected by modafinil . Conclusions In healthy volunteers without sleep deprivation modafinil has subtle stimulating effects on maintenance and manipulation processes in relatively difficult and monotonous working memory tasks , especially in lower performing subjects . Overlapping attentional and working memory processes have to be considered when study ing the noradrenergic modulation of the prefrontal cortex
We found that whilst most studies employing basic testing paradigms show that modafinil intake enhances executive function , only half show improvements in attention and learning and memory , and a few even report impairments in divergent creative thinking .
In contrast , when more complex assessment s are used , modafinil appears to consistently engender enhancement of attention , executive functions , and learning .
Importantly , we did not observe any preponderances for side effects or mood changes .
Modafinil is an FDA -approved eugeroic that directly increases cortical catecholamine levels , indirectly upregulates cerebral serotonin , glutamate , orexin , and histamine levels , and indirectly decreases cerebral gamma-amino-butrytic acid levels .
In addition to its approved use treating excessive somnolence , modafinil is thought to be used widely off-prescription for cognitive enhancement .
However , despite this popularity , there has been little consensus on the extent and nature of the cognitive effects of modafinil in healthy , non-sleep-deprived humans .