An apparatus and method for the recording of physiological variables in small animals are described. The apparatus is an integrated self-contained recorder including a converter of biological signals into a digital form, a data storage unit, a data output for transporting the stored data from the recorder after the end of recording session, a power source and an electrical connector arranged for connection of the recorder with at least one sensor of biological signal and mechanical fixation of the recorder at the head of an animal. The recorder may contain a sensor, which receives signals from an external source for synchronization of the stored data with external equipment or observed/registered animal behavior.
