Differential reinforcement of low rates

Li, A. Marek, G. Vosmer, G. and Seiden, L. MDMA-induced serotonin depletion potentiates the psychomotor stimulant effects of MDMA on rats performing on the differential-reinforcement-of-low-rate (DRL) schedule. Society for Neuroscience Abstracts 12 609, 1986. 

The original observation of long-term depletions of DA in the rhesus monkey was made during a study of the development of tolerance to the effects of daily injections of METH (Fischman and Schuster 1977). In this study, it was found that behavioral tolerance to METH on a differential-reinforcement-of-low-rate (DRL) task persisted long after the repeated METH regimen. In a similar study conducted later, monkeys treated with repeated METH showed reduced sensitivity to apomorphine and increased... 

Differential reinforcement of low rate (DRL) responding in a Skinnerbox has been used in different studies as a test for teratogenic effects on behavior. Prenatal treatment of rats vith haloperidol resulted in normal baseline level of lever pressing in a Skinnerbox for a water reward. However, like after postnatal haloperidol treatment, an increase in the number of sessions to criterion for DRL responding was observed in these animals (ref. 41). Simple acquisition of the bar-press response for water reward was shown to be affected by prenatal treatment vith chlorpromazine, but not by prenatal amphetamine treatment (ref. 137). The response rate, but not response accuracy, in a left-right alternation learning test in a Skinnerbox was increased after neonatal clomipramine treatment ref. 34). 

Lau CE, Wang Y, Falk JL. 1997. Differential reinforcement of low rate performance, pharmacokinetics and pharmacokinetic-pharmacodynamic modeling independent interaction of alprazolam and caffeine. J Pharmacol Exp Ther 281 1013-1029. 

It is not possible to define experimentally the effects of lead on cognitive function (e.g. learning and memory), and effects on arousal and motivation can complicate the observed picture. The definition of acquisition may also represent performance, as is the case in studies that report group differences on the first day of acquisition. Some types of learning problems are more sensitive to lead-related disruption than others. Simple pattern discrimination and passive avoidance are not especially sensitive to lead. Functional impairment by lead appears to increase as the task complexity increases (e.g. from discrimination tasks to differential reinforcement of low rate operant responding). This suggests that the possible consequences of lead exposure will only be uncovered when experimental design becomes more sophisticated than at present. 

A series of behaviors suggesting deficient response inhibition is also seen following developmental Pb exposure. Specific behavioral deficits are seen on tests of passive avoidance, one way active avoidance, differentied reinforcement of low rates of responding (DHL-EO)" and fixed interval schedules of operant controlled behavior operant extinction and operant response inhibition, spontaneous cdternation," "" and various discrimination reversal problems " "" have also been observed following developmental Pb exposure. 

Following FI schedule testing, each monkey was tested on another intermittent schedule, the DRL (differential reinforcement of low rate), which assessed the monkey s ability to inhibit responding. This required the monkey to wait at least 30 s before responding in order to receive a reward. Although the lead-treated monkeys were able to learn the task, they did so at a slower rate than controls and were more variable in their performance from day to day than the controls (similar to the FI results). 

O Donnell, J.M. (1993) Antidepressant-like effects of rolipram and other inhibitors of cyclic adenosine monophosphate phosphodiesterase on behavior maintained by differential reinforcement of low response rate. / Pharmacol Exp Tfcer 264(3) 1168-1178. 

Temporally-spaced responding is a modified fixed interval schedule, more commonly known as differential reinforcement of low (or high) rate. In this... 

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