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 .
Functional magnetic resonance imaging neuroactivation studies in normal subjects and subjects with the narcoleptic syndrome. Actions of modafinil.
Functional magnetic resonance imaging ( fMRI ) can be used to detect regional brain responses to changes in sensory stimuli . We have used fMRI to determine the amount of visual and auditory cortical activation in 12 normal subjects and 12 subjects with the narcoleptic syndrome , using a multiplexed visual and auditory stimulation paradigm . In both normal and narcoleptic subjects , mean cortical activation levels during the presentation of periodic visual and auditory stimulation showed no appreciable differences with either age or sex . Normal subjects showed higher levels of visual activation at 10:00 hours than 15:00 hours , with a reverse pattern in narcoleptic subjects ( P = 0.007 ) . The group differences in spatial extent of cortical activation between control and narcoleptic subjects were small and statistically insignificant . The alerting action , and imaging response , to a single oral dose of the sleep-preventing drug modafinil 400 mg were then determined and compared with placebo in both the 12 normal ( 8 given modafinil , 4 placebo ) and 12 narcoleptic subjects ( 8 modafinil , 4 placebo ) . Modafinil caused an increase in self-reported levels of alertness in 7 of 8 narcoleptic subjects , but there was no significant difference between mean pretreatment and post-treatment activation levels as determined by fMRI for either normal or narcoleptic syndrome subjects given modafinil . However , in the modafinil-treated group of 8 normal and 8 narcoleptic subjects , there was a clock time independent correlation between the initial level of activation as determined by the pretreatment scan and the post-treatment change in activation ( visual , P = 0.002 ; and auditory , P = 0.001 ) . No correlation was observed in placebo-treated subjects ( P = 0.99 and 0.77 , respectively ) . Although limited by the small number of subjects , and the lack of an objective measure of alertness , the findings of this study suggest that low cortical activation levels in both normal and narcoleptic subjects are increased following the administration of modafinil . Functional magnetic resonance imaging may be a valuable addition to established studies of attention
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 .