Temporal patterns of voluntary alcohol intake.

This paper describes methods of analysing temporal patterns of alcohol consumption by mice over time-courses of days or hours. Records of daily alcohol intake can be used to identify brief periods when the mice sobered up. These one-day 'breaks' apparently allow the previously acquired level of physical dependence to decay. Effective alcohol intake, calculated by taking account of breaks, is a good indicator of physical dependence. More detailed time studies show the circadian rhythm of intake and of blood alcohol levels. To analyse our records of alcohol consumption over successive 8-hour periods, we fitted the data to cosine curves. These curves show the amplitude of the intake rhythm, which in turn determines the stability of blood alcohol levels. The highest and most stable blood alcohol levels were obtained by administering alcohol in a liquid diet to individually-housed mice.