1. Modafinil modulation of the default mode network
- Author
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Minzenberg, Michael J, Yoon, Jong H, and Carter, Cameron S
- Subjects
Biological Psychology ,Cognitive and Computational Psychology ,Psychology ,Behavioral and Social Science ,Clinical Research ,Brain Disorders ,Basic Behavioral and Social Science ,Neurosciences ,1.1 Normal biological development and functioning ,6.1 Pharmaceuticals ,Neurological ,Adult ,Benzhydryl Compounds ,Brain ,Catecholamines ,Cognition ,Cross-Over Studies ,Double-Blind Method ,Female ,Functional Laterality ,Gyrus Cinguli ,Humans ,Magnetic Resonance Imaging ,Male ,Modafinil ,Nerve Net ,Neuropsychological Tests ,Parietal Lobe ,Prefrontal Cortex ,Psychomotor Performance ,Reaction Time ,Rest ,Default mode network ,Task-induced deactivation ,Gain control ,Negative BOLD response ,Medical and Health Sciences ,Psychology and Cognitive Sciences ,Psychiatry ,Biological psychology - Abstract
RationaleThe default mode network (DMN) is a functional network which is implicated in a range of cognitive processes. This network is proposed to consist of hubs located in the ventromedial prefrontal cortex (vmPFC), posterior cingulate/retrosplenial cortex (PCC/rSpl), and inferior parietal lobule (IPL), with other midline cortical and temporal lobe nodes connected to these hubs. How this network is modulated by neurochemical systems during functional brain activity is not yet understood.ObjectivesIn the present study, we used the norepinephrine/dopamine transporter inhibitor modafinil to test the hypothesis that this drug modulates the DMN.MethodsEighteen healthy right-handed adults participated in a double-blind, placebo-controlled study of single oral dose modafinil 200 mg. They performed a simple visual sensorimotor task during slow event-related fMRI. Drug effects were interrogated within the DMN defined by task-induced deactivation (TID) on placebo.ResultsThere was a trend toward faster reaction time (RT) on modafinil (Cohen's d = 0.38). Brain regions within the DMN which exhibited significant modafinil-induced augmentation of TID included vmPFC, PCC/rSpl, and left IPL. Across subjects, the modafinil effect on TID in the vmPFC was significantly and specifically associated with drug effects on RT speeding.ConclusionsModafinil augments TID in the DMN to facilitate sensorimotor processing speed, an effect which may be particularly dependent on changes in vmPFC activity. This is consistent with the gain control function of catecholamine systems and may represent an important aspect of the pro-cognitive effects of modafinil. more...
- Published
- 2011