ABSTRACT
The effects of the interstimulus interval (ISI) in Pavlovian conditioning are reexamined in this chapter due to the controversy that remains regarding the observable effects attributable to the ISI and the lack of current theory’s ability to account for recent experimental results. According to the prevailing view, backward conditioning (negative ISI) and simultaneous conditioning (zero ISI) are incapable of producing conditioned responses. However, the author presents behavioral and recent neurophysiological experimental evidence suggesting the conditions under which excitatory backward and simultaneous conditioning are possible. The author concludes that the negative and positive effects attributable to backward and simultaneous conditioning are due to contrasting experimental procedures.
