John R . Harsh

Learn More
CONTEXT Narcolepsy, a neurological disorder affecting 1 in 2000 individuals, is associated with HLA-DQB1*0602 and low cerebrospinal fluid (CSF) hypocretin (orexin) levels. OBJECTIVES To delineate the spectrum of the hypocretin deficiency syndrome and to establish CSF hypocretin-1 measurements as a diagnostic tool for narcolepsy. DESIGN Diagnosis,(More)
The immediate psychophysiological and behavioral effects of photic stimulation on humans [bright light (BL) of 5K lux or dim light (DL) of 50 lux] were assessed in male subjects (N = 43) under four different conditions. For one condition the same subjects (N = 16) received alternating 90-min blocks of BL and DL during the nighttime h (2300-0800 h) under(More)
Event-related potentials (ERPs) following infrequent and frequent stimuli were studied as subjects moved from wakefulness to sleep. Subjects were instructed to respond to the infrequent "target" stimuli (attend condition) or to ignore the stimuli (ignore condition). Parietal P300, prominent following target ERPs in wakefulness under the attend condition,(More)
This report describes night-time sleep and daytime sleepiness in a large (N=530) sample of patients meeting the International Classification of Sleep Disorders criteria for diagnosis of narcolepsy. Sleep data were obtained from polysomnographic recordings on two consecutive nights. Sleepiness was assessed using the Multiple Sleep Latency Test, the(More)
Stimulus factors known to influence the amplitude of the well known endogenous event-related potential (ERP) component P300 were manipulated to determine whether they have the same, or a different, influence on the amplitude of positivities of the sleep ERPs identified as P220, P450, and P900. Behavioral responsiveness and ERPs were recorded as subjects(More)
This research assessed the impact of one night of sleep deprivation on the amplitudes of NREM-sleep event-related potentials (NREM ERPs) and on the frequency of occurrence of related electroencephalogram activity including sleep spindles, arousals, K-complexes, and vertex sharp waves (VSWs). The NREM ERPs identified included P220, N350, P450, N550 and P900.(More)
Modafinil is a wake-promoting drug approved by the FDA for the treatment of narcolepsy. Recent evidence suggests that modafinil may improve learning and memory processes. To further evaluate possible cognitive properties associated with modafinil, male Sprague-Dawley rats were tested in a delayed nonmatching to position (DNMTP) task. A modified water maze(More)
OBJECTIVES To assess the efficacy and safety of modafinil for improving wakefulness in narcolepsy patients treated previously with psychostimulants. BACKGROUND Modafinil has become a standard therapy for improving daytime wakefulness in narcolepsy patients and may be a useful therapeutic alternative to psychostimulants used to improve waking function in(More)
OBJECTIVE This study assessed the efficacy and safety of armodafinil, the longer half-life enantiomer of modafinil, for the treatment of excessive sleepiness in patients with narcolepsy. RESEARCH DESIGN AND METHODS This was a multicenter double-blind study with 196 patients (aged 18-65 years) randomized to receive armodafinil 150 mg (n = 65), armodafinil(More)
Whether humans react to olfactory stimuli presented in sleep was assessed. Responses of ten participants (mean age = 22.8 years) were recorded to repeated three-minute periods of either air alone or to a peppermint odor (0.26 mg/liter) during stage 2 sleep. These responses included behavioral (awakening, microswitch closure), autonomic (heart rate, EMG,(More)