Blough P M, Blough D S
Department of Psychology, Brown University, Providence, RI 02912.
Psychopharmacology (Berl). 1989;97(1):80-4. doi: 10.1007/BF00443417.
Pigeons pecked at target forms, located in arrays of distractors. In experiment 1 the number of distractors and their similarity to the target varied. In experiment 2, similarity was varied over a more extended range. Drug tests used morphine in doses ranging from 1 to 6 mg/kg, naloxone (0.3-3 mg/kg) alone and combined with morphine. Morphine had relatively small effects on accuracy; however, it produced pronounced elevations in reaction time. Significant interactions with display variables indicated a visual component to the morphine effect. Naloxone alone had no effect; naloxone combined with morphine blocked the morphine effect.
