Patients are carefully screened to have DSM primary insomnia, and do not have another disorder than may cause a sleep disturbance. After a 2-week baseline period, the subjects undergo a screening sleep study to rule out sleep apnea and periodic limb movement disorder. Then they undergo the NSLP procedure. In that procedure, there pre-bedtime EEG recordings and questionnaire responses taken. Then at a planned time, the subjects go to bed and try to sleep while there EEG signals are recorded. After the first and second sleep cycles, they are awakened for one minute, then asked to return to sleep. In the morning additional recordings and questionnaire responses are obtained. Two nights later they repeat a baseline NSLP procedure. The controls then end their participation. The Patients then receive an open treatment with eszopiclone and behavioral treatments so that their insomnia may improve. After 2 weeks intervention, the patients complete one NLSP night. The goal of the study is to see if there can be data to support the idea that the sleep onset process might harbor a sign of primary insomnia that could be used for the development of a better medical model of primary insomnia.