(+/-)3,4-methylenedioxymethamphetamine, d-amphetamine, and cocaine impair delayed matching-to-sample performance by an increase in susceptibility to proactive interference

Behav Neurosci. 2005 Apr;119(2):455-63. doi: 10.1037/0735-7044.119.2.455.


This study compared the effects of (+/-)3,4-methylenedioxymethamphetamine, d-amphetamine, and cocaine on performance of rats in a delayed matching-to-sample procedure using a variety of indices of performance to determine the mechanism by which working memory task impairments arise. All 3 drugs produced an overall delay-independent decrease in accuracy rather than a delay-dependent increase in the rate of forgetting. This impairment arose as a result of current-trial choice responses being progressively more affected by responses made in the immediately preceding trial as drug dose increased. Therefore, all 3 drugs produced qualitatively similar disruptions in memory task performance best characterized as an impairment arising from proactive sources of interference.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cocaine / pharmacology*
  • Dextroamphetamine / pharmacology*
  • Discrimination Learning / drug effects*
  • Dopamine Uptake Inhibitors / pharmacology*
  • Hallucinogens / pharmacology*
  • Male
  • Memory / drug effects*
  • N-Methyl-3,4-methylenedioxyamphetamine / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Reproducibility of Results
  • Task Performance and Analysis


  • Dopamine Uptake Inhibitors
  • Hallucinogens
  • Cocaine
  • N-Methyl-3,4-methylenedioxyamphetamine
  • Dextroamphetamine