The Effects of Cocaine on the Aggressive Behavior of Mice, Pigeons and Squirrel Monkeys

Abstract

Historically cocaine, a central nervous stimulant, has been associated with subjective effects of euphoria, elevation of mood, indifference to pain, and increased vigor and muscular strength (Jaffe, 1965; Byck, 1974; Maurer and Vogel, 1967). Chronic use and high doses have been associated with irritability, anxiety, paranoid delusions and violence (Maurer and Vogel, 1967; Byck, 1974). Because cocaine shares many properties with the amphetamines and several studies have shown that amphetamine can potentiate aggression, there is supposition that cocaine may influence aggressive behavior but there is limited data on cocaine and violence to support this conclusively. Most information on the effects of cocaine on human behavior are anecdotal or clinical observations of addicts (Post, Kotin, and Goodwin, 1974). The experimental literature on the effects of cocaine is also sparse. Smith (1964) administered cocaine to pigeons on a fixed interval-fixed ratio (FI-FR) schedule for food. Responding on the FI schedule was increased at the higher doses of cocaine but FR rates were depressed. Hill, Bell and Wikler (1967) report no effect of cocaine administration (10 mg/kg s.c.) to rats on lever pressing for food on a conditioned suppression procedure. Kosman and Unna (1968) report increased endurance to swimming in dogs given cocaine and Simon, Sultan, Chermat and Boissier (1972) report hyperactivity and increased explorations in rats and mice at 2–4 mg/kg with stereotyped behavior occurring at 8 mg/kg. Kosman and Unna (1968) have reported that rats working on a water-reinforced task exhibited no tolerance to chronic administration of cocaine and performance returned to control levels upon withdrawal of the drug. Chronic administration of cocaine in humans does not produce physiological addiction (Jaffe, 1965; Post et al., 1974).