The effects of time-out locus during fixed-ratio reinforcement

Abstract

Pigeon's keypecking was reinforced on a multiple fixed-ratio schedule. All three components were fixed ratio 60; a 10-sec time-out regularly appeared after the tenth response in one component and after the fiftieth response in another. Pause duration was shortest with no time-out, longest with the time-out late in the ratio. In time-out components, response rate was low preceding the timeout, high immediately following it. The total time from rsponse initiation to subsequent reinforcement was highly predictive of pause duration. Immediate repetition of a component generally produces shorter pausing than when it was preceded by a different component.A time-out (TO) is a signaled period of time associated with extinction (Ferster & Skinner, 1957) during which reinforcement is unattainable (Leitenberg, 1965). It is generally signaled by a change in some exteroceptive stimulus within the operant chamber.The present study involves the systematic introduction of TO during fixed-ratio (FR) performance. The FR, which prOvides reinforcement following a fixed number of responses, typically generates a period of pause followed by a rapid sequence of responses termin::tting with reinforcement. A major determinant of the pause duration is the length of the ratio itself. Some research (Neuringer & Schneider, 1968) suggests that the time devoted to the sequence of responses to complete the ratio affects pause duration.The i'1tent of the present analysis is twofold. For one, we are concerned with pause duration as it is affected by the time involved in obtaining reinforcement. Our procedures included a mUltiple schedule of reinforcement in which an FR 60 was always employed. The three distinctively cued components included two with 10-sec TOs regularly provided at different loci in the response sequence. Our second concern was an examination of the influence of the TO and its position, in the sequence of responses, on local variations in response rate. METHOD SubjectsThree male white Carneaux pigeons, between 2 and 3 years old, were maintained at 80% of their free-feeding weights. All birds were experimentally naive at the start of the experiment. ApparatusA standard Lehigh Valley Electronics two-key operant chamber for pigeons was used. Only the key to the left of the food hopper was operative for purposes of this study. Temporal data were recorded on Pressin printing counters, mounted in Scientific Prototype control housings and pulsed at 10 Hz by a Scientific Prototype reed clock_ The test chamber was housed in a sound-attenuating enclosure, and white noise was provided for further masking. Closure of the response key required a force of approximately .2 N_ ProcedureThe three pigeons were shaped to peck the left key of the operant chamber, transilluminated white. Subsequent training involved systematic increases in the responses required for reinforcement until responding on FR 60 in the presence of the white key stablized. The birds then received 2 days of training with key light either red, green or white, changing after e...

Quantification of pausing on fixed-ratio schedules of reinforcement

“…Log-transformed data from the Crossman et al (1974) Psychological Reports, 1973Reports, ,32,1925Reports, -1928 also observed this effect (e.g ., Barowsky & Mintz, 1978), and it undoubtedly contributes to some of the variability in the present observations. Finally, Figure 3 presents the data collected in the Ball State University laboratories (log transformations of the median pause from the last five sessions at a ratio size).…”

The effects of time-out duration during fixed-ratio reinforcement

“…Present data indicate • that the greater the duration of the TO, the greater the disruption of the preceding behavior. Barowsky (1973) and Barowsky and Mintz (1975) have shown that the position of the TO in the FR sequence generates a similar effect : the later the TO, the greater the disruption. In those studies, prolongation of the TOI was largely related to the length of the pre-TO sequence of responses; the TO duration was constant.…”

“…Similar effects have been observed by Zeiler (1970Zeiler ( , 1972 where the ratio requirement was held constant, while the time necessary to complete the ratio was varied. Further, Barowsky (1973) and Barowsky and Mintz (1975) .. a FR sequence also altered the time of involvement in the ratio, which was in turn predictive of pause duration. The addition of the TO component in itself cannot account for the increase in pause duration.…”