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Discrimination and emission of different key-peck durations in the pigeon.

1978; American Psychological Association; Volume: 4; Issue: 1 Linguagem: Inglês

10.1037/0097-7403.4.1.1

1939-2184

John M. Ziriax, Alan Silberberg,

Banana Cultivation and Research

John M. Ziriax and Alan SilberbergAmerican UniversityIn Experiment 1, food reinforcement depended on pigeons' discriminationsamong three bands of key-peck duration: (a) 0-msec peck (no peck); (b)0-20-msec peck (short pecks) ; and (c) peck durations between 60 and 90,110, or 180 msec, depending on the subject (long pecks). Trials began withthe random selection of a peck-duration band and the presentation of a bluecenter key. The occurrence of a blue-key response within the criterion-bandduration accessed the discrimination phase. This phase consisted of threedifferently colored keys, each color associated with a response-duration band.Only selection of the discrimination-phase color appropriate to the priorblue-key response-duration band was reinforced. All birds accurately dis-criminated prior response bands. In Experiment 2, trials began with a colorindicating the appropriate response band to be emitted, either a short or longpeck. Birds successfully emitted and discriminated both bands, a result in-consistent with Schwartz and Williams's finding that only long pecks canbe reinforced. An interpretation of the peck-duration literature is presented,which views duration as a correlate of response strength.Recent work, based in large measure on a the response-independent delivery of grain,study by Brown and Jenkins (1968), sug- Successive key light-food trials were sepa-gests that key pecking is not invariably sensi- rated by an intertrial interval (ITI) of 1 min.tive to its consequences. In their study, food- After 20 to 200 trials, pigeons began to peckdeprived pigeons were exposed to the illumi- the lighted key, even though key pecking wasnation of a response key for 8 sec prior to unrelated to food delivery.Brown and Jenkins noted that while these~~„ . ~T key pecks were gratuitous, in that reinforce-This research was supported by National Insti- inHpnwiHwil- nf tVipir nrrnrrmretute of Mental Health Grant MH22881 to The