Adjustment to intermittent access in rats drinking saccharin: II. Adjustment of lapping rate.

Hungary rats were permitted to drink saccharin under conditions in which (a) the drinking spout was available continuously, or (b) it was withdrawn during alternate 30-sec periods. Rats adjust to such constraint by increasing their integrated lap rate (laps/min). We show that one way in which they do this is to lap at a higher rate within bursts of lapping. This faster lapping is not an artifact of forced interruptions and resumptions. It cannot only be maintained over a drinking session, but also initiated midway through the session if restricted access is imposed then. Therefore, the period of the lapping cycle can be adjusted, within limits, in response to situational constraints on access to the fluid.