Definition reprinted with permission from Hood, Stephen B. (editor) available from Stuttering Foundation of America: [amazon 093338825X inline]
The process of acquiring, establishing, learning, modifying, or extinguishing behavioral and/or emotional responses. Forms of conditioning include: classical (Pavlovian, respondent, reflex) conditioning; counter conditioning; operant (Skinnerian, instrumental) conditioning; vicarious conditioning; deconditioning. When a response that formerly occurred only rarely or not at all is "conditioned" to occur more frequently, learning is assumed to have taken place, provided that the change is relatively long lasting. Conditioning may occur by chance, or by conscious manipulation of antecedent stimuli and/or contingent consequences.