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ADDH and methylphenidate responders: effects on behavior controlled by complex reinforcement schedules
G J DuPaul1, M D Rapport, S A Vyse
1Department of Psychiatry, University of Massachusetts Medical Center, Worcester 01655.
International Clinical Psychopharmacology
|October 1, 1988
Summary
Methylphenidate (MPH) affects children with Attention Deficit Disorder with Hyperactivity (ADDH) in a rate-dependent manner. This study observed MPH
Area of Science:
- Pharmacology
- Neuroscience
- Behavioral Science
Background:
- Methylphenidate (MPH) is a common treatment for Attention Deficit Disorder with Hyperactivity (ADDH).
- Evidence suggests MPH effects are rate-dependent, but its impact on complex operant behavior is not well understood.
Purpose of the Study:
- To investigate the effects of various methylphenidate (MPH) doses on operant key-pressing behavior in children with ADDH.
- To determine if MPH exhibits rate-dependent effects on behavior controlled by complex reinforcement schedules.
Main Methods:
- Twenty children with ADDH, who responded positively to MPH, participated in a double-blind, placebo-controlled study.
- Participants performed a key-pressing task under different MPH doses and placebo conditions in a randomized sequence.
- Behavioral data were collected following a drug-free training period.
Main Results:
- Methylphenidate (MPH) demonstrated rate-dependent effects on operant behavior across both high- and low-rate reinforcement schedules.
- The magnitude of these rate-dependent effects varied depending on the MPH dosage administered.
- Individual differences in response strength were observed across participants.
Conclusions:
- The findings support the existence of rate-dependent phenomena in human operant behavior under MPH.
- Results provide insights into optimizing pharmacotherapy parameters for children diagnosed with ADDH.
- Further research is warranted to explore the nuances of MPH's effects on complex behaviors.
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