HEART-RATE CHANGES IN CHRONIC INSOMNIA

This study assessed physiological activity in patients with chronic in somnia before sleep, during sleep and in response to acute stress. Twe nty-four subjects with chronic insomnia and 25 normal sleepers slept i n the laboratory overnight and were given a stressful performance task in the morning. Heart rate was significantly higher in the insomniac group at night. The next morning, heart rate was not different at base line, but was significantly higher during the performance task in the insomniac group. These results are discussed as supporting the notion that insomniacs have greater physiological responsivity to stress. Fur ther research is needed to determine if altered physiological activity is a cause or consequence of insomnia.