Assessment of brain activity during memory encoding in a narcolepsy patient on and off modafinil using normative fMRI data

Psychology Department, Brigham Young University, Provo, UT 84602, USA.
Neurocase (Impact Factor: 1.12). 02/2012; 18(1):13-25. DOI: 10.1080/13554794.2010.547508
Source: PubMed


We present behavioral and functional magnetic resonance imaging (fMRI) findings of a 20-year-old female with narcolepsy who completed a standardized fMRI-adapted face memory task both 'off' and 'on' modafinil compared to a normative sample (N = 38). The patient showed poor recognition performance off modafinil (z = -2.03) but intact performance on modafinil (z = 0.78). fMRI results showed atypical activation during memory encoding off modafinil, with frontal lobe hypoactivity, but hippocampal hyperactivity, whereas all brain regions showed more normalized activation on modafinil. Results from this limited study suggest hippocampal and frontal alterations in individuals with narcolepsy. Further, the results suggest the hypothesis that modafinil may affect brain activation in some people with narcolepsy.

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    • "This finding must, however, be validated by comparing fMRI in KLS and other differential diagnosis. In narcolepsy, fMRI has been used to investigate the relation between brain activation and pharmacological therapy (46–48). Although results were promising, they remain hypothetical until validated in larger patient groups. "
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