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author:("blamed, N M")
1.  Sensitivity to relative reinforcer rate in concurrent schedules: independence from relative and absolute reinforcer duration. 
Twelve pigeons responded on two keys under concurrent variable-interval (VI) schedules. Over several series of conditions, relative and absolute magnitudes of reinforcement were varied. Within each series, relative rate of reinforcement was varied and sensitivity of behavior ratios to reinforcer-rate ratios was assessed. When responding at both alternatives was maintained by equal-sized small reinforcers, sensitivity to variation in reinforcer-rate ratios was the same as when large reinforcers were used. This result was observed when the overall rate of reinforcement was constant over conditions, and also in another series of concurrent schedules in which one schedule was kept constant at VI ached 120 s. Similarly, reinforcer magnitude did not affect the rate at which response allocation approached asymptote within a condition. When reinforcer magnitudes differred between the two responses and reinforcer-rate ratios were varied, sensitivity of behavior allocation was unaffected although response bias favored the schedule that arranged the larger reinforcers. Analysis of absolute response rates ratio sensitivity to reinforcement occurrred on the two keys showed that this invariance of response despite changes in reinforcement interaction that were observed in absolute response rates on the constant VI 120-s schedule. Response rate on the constant VI 120-s schedule was inversely related to reinforcer rate on the varied key and the strength of this relation depended on the relative magnitude of reinforcers arranged on varied key. Independence of sensitivity to reinforcer-rate ratios from relative and absolute reinforcer magnitude is consistent with the relativity and independence assumtions of the matching law.
PMCID: PMC1284806  PMID: 11256865
2.  A behavioral model of infant sleep disturbance. 
Chronic sleep disturbance, such as bed refusal, sleep-onset delay, and night waking with crying, affects 15% to 35% of preschool children. Biological factors, particularly arousals associated with recurrent episodes of rapid-eye-movement sleep, render infants vulnerable to repeated awakenings. Parental failure to establish appropriate stimulus control of sleep-related behaviors and parent-mediated contingencies of reinforcement for sleep-incompatible behaviors may shape and maintain infant sleep disturbance. Treatment and prevention strategies are discussed, and research needs are identified.
PMCID: PMC1297876  PMID: 8307835
3.  Quantification of the effects of chlorpromazine on performance under delayed matching to sample in pigeons. 
The effects of four doses of chlorpromazine (dose range 0.5 to 12.5 mg/kg) on performance under a delayed matching-to-sample procedure in pigeons was investigated, using the exponential model of memory (White, 1985). Performance was measured using a bias-free measure of discriminability, log d (Davison & Tustin, 1978), and negative exponential functions were fitted to individual-subject and group data at each dose level. A decrease in matching accuracy was found to be caused by an increase in the rate of forgetting, b, and a decrease in the initial discriminability, log d0. Changes in rate of forgetting and discriminability occurred at doses that had no statistically significant effect on response latency. The exponential model of memory accounted well for the data and provided a useful way of quantifying the effects of chlorpromazine on the processes involved in delayed matching-to-sample performance.
PMCID: PMC1338924  PMID: 2723577

Results 1-3 (3)