- All subjects will meet diagnostic criteria for Psychophysiological Insomnia according to the International Classification of Sleep Disorders (ICSD). Criteria are: the complaint of insomnia and impaired daytime function; an indication of learned sleep-preventing associations and somatized tension; active help seeking. The complaint of disturbed sleep will have one or more of the following characteristics: >30 minutes to fall asleep and/or >2 awakenings per night of >15 minutes duration and/or wake after sleep onset time of > 30 minutes, problem frequency >4 nights/ week, and problem duration >6 months. In addition, all subjects will complain of fatigue and/or sleepiness at intake.