An inexpensive automatic activity monitor for small primates.

An activity cage has been designed to provide a quantitative measure of locomotor activity in small primates. Movement is detected by the interruptions of photocell beams, which are counted electronically and stored in on-board memory for subsequent display or entry into a computer. The device functions independently, and does not require a computer to be on-line during data collection. Data thus obtained have proven reliable, and are a valid record of the activity of the animal.