MUTUAL CROSS-ADAPTATION OF THE VOLATILE STEROID ANDROSTENONE AND A NONSTEROID PERCEPTUAL ANALOG

Self- and cross-adaptation are believed to result from stimulation of the same olfactory sensory channels. These adaptation phenomena were s tudied after exposures to 5alpha-androst-16-en-3-one (androstenone) an d a synthetic perceptual analog (DMCMC), viz. a racemic mixture of the isomers ',4'-dimethyl-cyclohexyl)-2(R)-methylcyclohexanone and ',4'-d imethylcyclohexyl)-2(S)-methylcyclohexanone. In Experiment 1, six subj ects very sensitive to androstenone received four randomized sequences of six concentrations of four odorants (androstenone, DMCMC, amyl ace tate, and Galaxolide(R); plus blanks) before and following adaptation to either androstenone or DMCMC. Exposure to each odorant resulted in self-adaptation. Measures of stimulus intensity and identification thr eshold revealed reciprocal cross-adaptation between androstenone and D MCMC, but no cross-adaptation to amyl acetate or Galaxolide. The degre e of cross-adaptation was asymmetric; adaptation to DMCMC resulted in more complete adaptation to androstenone than vice versa. This asymmet ry was apparently due to intensity differences; when stimuli were matc hed for intensity, the asymmetry disappeared (Experiment 2). These res ults demonstrate cross-adaptation for qualitatively similar, but not d issimilar, odors and suggest that androstenone and its perceptual anal og DMCMC share the same sensory channels.