Pocket-Neurobics. The Pendant HEG pIR ("passive infra red") reads the signal generated by the Jeff Carmen pIR headband and sends it wirelessly to a PC. The pIR headband measures brain metabolism (heat) in a particular IR band. The Pendant pIR can also read thermocouple-type sensors to measure skin temperature. A Biofeedback software application is also required (some designs are included in the accompanying CD). The Pendant is powered by a 9V rechargeable battery supplied.