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C Iglauer

Publications and source records attributed to C Iglauer.

4 recordsLinked to original sources
PubMed1976

Relative reinforcer magnitude under a nonindependent concurrent schedule of cocaine reinforcement in rhesus monkeys.

Lever pressing by three rhesus monkeys was maintained under a two-lever concurrent schedule of cocaine reinforcement. Responding on one lever (constant-dose lever) produced a constant dose of 0.05 or 0.1 mg/kg/injection arranged according to a variable-interval 1-min schedule. Responding on the other lever (variable-dose lever) produced a comparison dose of cocaine (0.013 to 0.8 mg/kg/injection), also under a variable-interval 1-min schedule. The two variable-interval schedules were made nonindependent by arranging that the assignment of a reinforcer by one schedule inactivated the second schedule until the assigned reinforcer had been obtained. This modification ensured that the two cocaine doses were obtained with approximately equal frequency, regardless of the distribution of the subject's responding. Preference, indicated by relative response frequency on the variable-dose lever, was almost always for the larger of the doses and was a monotonic function of the comparison dose, except at the highest doses. Preferences at the highest comparison doses may have resulted from the low overall response rates exhibited at these doses. Relative response frequencies on the variable-dose lever roughly matched relative reinforcer magnitude (mg/kg/injection available on the variable-dose lever divided by the sum of mg/kg/injections available on each lever).

Animals↗
PubMed1974

Concurrent performances: reinforcement by different doses of intravenous cocaine in rhesus monkeys.

Different doses of intravenous cocaine reinforced the lever pressing of rhesus monkeys under two-lever concurrent or concurrent-chain schedules. Under the concurrent procedure, responding produced drug reinforcers arranged according to independent variable-interval 1-min schedules. Under the concurrent-chain procedure, responding in the variable-interval link led to one of two mutually exclusive, equal-valued, fixed-ratio links; completion of the ratio produced a drug reinforcer. Under both procedures, responding on one lever produced a constant dose of 0.05 or 0.1 mg/kg/injection, while on the other lever, dose was systematically varied within a range of 0.013 to 0.8 mg/kg/injection. Preference, indicated by relative response frequency on the variable-dose lever during the variable-interval link, was always for the larger of the doses. Relative response frequencies on the variable-dose lever roughly matched relative drug intake (mg/kg of drug obtained on variable lever divided by mg/kg of drug obtained on both levers). For many dose comparisons, responding occurred and reinforcers were obtained almost exclusively on the preferred lever. Overall variable-interval rates generally were lower than with other reinforcers, and these low rates, under the experimental conditions, may have occasioned the exclusive preferences.

Animals↗
PubMed1971

Auditory generalization gradients for response latency in the monkey.

Two monkeys were trained to press and hold a response key in the presence of a light and to release it at the onset of a pure tone. Initially, all responses with latencies shorter than 1 sec were reinforced without regard to the frequency of the pure tone, and the intensity of the pure tone that resulted in equal latencies at each frequency was determined. The second stage of the experiment consisted of discrimination training, during which releases to one pure-tone frequency (positive stimulus) were reinforced and releases to a second frequency (negative stimulus) were extinguished. Median latencies to the negative stimulus slowly increased as did the variability of the latency distribution for the negative stimulus. There was no evidence of a concurrent decrease in latencies to the positive stimulus indicative of behavioral contrast. The third part of the experiment consisted of determining maintained generalization gradients by increasing the number of nonreinforcement stimuli. The gradients that eventually resulted showed approximately equal latencies to all frequencies of the negative stimulus and shorter latencies to the positive stimulus frequency.

Animals↗