Fig. 1. Rats were trained to localize airflow or light.

(A) The arena’s entrance door is opposite five fans, placed around the arena circumference. A fence confines the rat. Black solid lines indicate checkpoints. Five holes (black circles) allowed access to tunnels beneath the table (gray shadow) that led to a water reward port (reward 1, black star), activated only for correct trials. A ramp led back to the holding box where a second reward (reward 2, black star) was given for correct trials. (B) Airspeed color map shows that the maximum speed lies approximately along the line connecting fans and the entry door. (C) Five rats’ trajectories (all correct trials before vibrissal removal) superposed on airspeed color map.