Simultaneous classical conditioning of two effector systems.

The experiment reported here was an attempt to develop an experimental procedure for independent classical conditioning of two different response systems, the skin conductance response (SCR) and the eyelid response. In a differential conditioning design with human subjects (N = 50) two different unconditioned stimuli were used, a white noise (US1) and airpuff (US2). Two conditioned stimuli (CS11 and CS12) were paired with US1, and two other CSs (CS21 and CS22) were paired with US2. A special trial architecture was used to accomplish measurement of both anticipatory SCR and eyelid responses during each trial. Significant eyelid differentiation as well as significant SCR (especially second interval responses) differentiation developed.