A Computer Analog of Shuttlebox Avoidance by Human Subjects

Pilot research using a one-hand operated see-saw shuttlebox device demonstrated that (a) subjects who were told that they could do something about the shock aversive stimulus learned avoidance faster than those who were not told, (b) shocks in another apparatus prior to conditioning interfered with avoidance conditioning, and (c) a non-noxious tone stimulus could produce avoidance learning equivalent to that produced with a noxious shock stimulus. The two experiments reported here used the same basic paradigm but substituted a microcomputer analog apparatus for the see-saw shuttlebox. The first experiment showed that using two buttons on the keyboard to move an on-screen figure back and forth was as effective as using a joy-stick manipulandum to produce the same movement and that inclusion of a trial on which avoidance was not possible in every block of 5 avoidance trials had no debilitating effect. It also showed that an FR3 schedule (3 crossovers necessary for an avoidance) made acquisition significantly more difficult. A second experiment partially replicated the first and, in addition, demonstrated that a VR3 schedule increased the difficulty of avoidance acquisition even further.