The specificity of the effect of shock on the acquisition and retention of motor and verbal habits.

The history and present status of the law of effect.

“…1. A large number of different organisms have been spurred on to better learning by punishment: 10 earthworms (325), cockroaches (261,300), dancing mice (324), rats (e.g., 20,54,56,57,111,116,155,193,106,199,200,201,202,204,206,301,307,322), chicks (36), cats (53), and, last but not least, human beings (10,12,13,19,24,25,26,27,41,55,79,80,87,137,138,172,173,217,218,302).…”

“…2. There has been rather general agreement that relatively severe punishment (intensive shock) is most effective in the learning of simple habits such as black-white discrimination and simple maze patterns, and that relatively mild punishment is optimal in the case of difficult tasks such as more complex types of discrimination and exacting maze patterns (12,26,36,53,326,328).…”

“…3. The effects of shock may become disruptive (12,79,80,87,294,303), especially if applied early in the learning process (25,206,218). Shock may also lead to increased variability of responses as compared with milder forms of punishment (260).…”

“…If the experimenter works outside this range of combinations, punishment fails to yield significant results (Thorndike and co-workers). If he works with several combinations of conditions, he may easily find that punishment is effective in one case but not in the other and certainly that it varies in effectiveness (12,26,87). If he works with only one set of parameters, he may be tempted to overgeneralize.…”

“…Thus Thorndike and his co-workers have always concerned themselves with the history of specific rewarded and punished responses, finding punishment ineffective. Other investigators have found, however, that punishment may have a much more general effect: there may be a general improvement in performance, with unpunished responses benefiting along with the specifically punished ones (10,12). Even if the punishment itself is made non-specific ("non-informative shock"), and not administered as a consequence of any particular response, there is still a facilitating effect (11,12,19,25,79,80).…”