Fig. 5. Results from the sensory preconditioning experiments. In the preconditioning phase, the compound stimulus is presented without reinforcement. Results from corresponding half-experiments have been pooled. (A) 10 min of preconditioning (N=56). (B) 16 min of preconditioning (N=56). In the final test, the alternative stimulus to that used in the training period is used. Cross-hatched columns, training; open columns, test period; shaded areas, compound stimulus; unshaded areas, single stimulus. Values are means ± S.E.M.