EFFECT OF ILLUMINATION AND D-AMPHETAMINE ON THE ACTIVITY OF THE RHESUS MACAQUE

The activity of the Rhesus macaque was measured under three levels of ambient illumination and three dosages of d-amphetamine. Analysis of variance indicated that activity increases as a function of increasing level of illumination and decreases as a function of increasing dosages of amphetamine. The interaction effect was nonsignificant.

BEHAVIORAL-NEUROCHEMICAL CORRELATION IN REACTIVE AND NONREACTIVE STRAINS OF RATS

Male and female rats of the Maudsley reactive and Maudsley nonreactive strains were tested in the open-field to obtain ambulation and defecation scores. They were later killed, and their brains were dissected into five portions and analyzed for serotonin. Males defecated more and ambulated less than females, and nonreactive males ambulated more and defecated less than reactive males. These behavioral differences were significant (p .05). A statistically significant difference was found for the amounts of serotonin in specific regions of the brain between males and females (males higher) and between reactive and nonreactive males (reactive higher). Significant negative correlations between serotonin values in specific regions of brain and ambulation scores were found in these animals viewed as a group or even within a given strain and sex.

SOME PHARMACOLOGICAL EFFECTS OF A SERIES OF TRYPTAMINE DERIVATIVES

The methods of synthesis and some pharmacological properties of a number of N-substituted tryptamines are described. Peripheral vasopressor activity decreased with increase in complexity of the substituent and was not related to toxicity or to behavioural activity. Activity in increasing the rectal temperature of rabbits appeared to parallel modifications in the open-field behaviour of rats. Some compounds were investigated for their ability to block a conditioned avoidance-response in rats and to affect operant conditioning in cats. Evidence is presented which suggests that the tryptamine derivatives are metabolized in vivo to more active forms.

LABORATORY CONTROL OF TOE-SUCKING IN A YOUNG RHESUS MONKEY BY TWO KINDS OF PUNISHMENT

Both response-contingent withdrawal of a visual reinforcement and response-contingent presentation of an aversive stimulus (loud noise) were found to be effective in suppressing toe-sucking in a young rhesus monkey.

BEHAVIOR STABILITY AND RESPONSE RATE AS FUNCTIONS OF REINFORCEMENT PROBABILITY ON "RANDOM RATIO" SCHEDULES

A random ratio schedule is one under which every ordinally specified response has the same probability of reinforcement as any other. Data have been gathered at several values of this type of schedule, using a separate group of pigeons for each schedule value and giving prolonged exposure to each value. No simple relationship was found between response rate and reinforcement probability. In general aspect group data from the present experiment agree with those from a single organism study cited. It was shown that 40 to 50 days of exposure to random ratio schedules yields fairly asymptotic response rate data. The tabulated raw data, and the results of some statistical manipulations, have been deposited with the American Documentation Institute.

PROBABILITY-LEARNING BY THE TURTLE

Tested in a two-choice situation, the painted turtle, Chrysemys picta picta, shows random probability-matching in visual problems and in confounded visual-spatial problems, but only maximizing or nonrandom matching (reward-following) in spatial problems. The results are compared with those of analogous experiments on fish, bird, and mammal.

SEQUENTIAL BEHAVIOR INDUCED REPEATEDLY BY STIMULATION OF THE RED NUCLEUS IN FREE MONKEYS

Rhesus monkeys in a colony were stimulated by means of intracerebral electrodes controlled by radio, for 5 seconds every minute, day and night, for periods up to 14 days. Stimulations of the red nucleus evoked a reliable sequence of behavior including bipedal locomotion, climbing, vocalization, and social interactions. During periods of spontaneous sleep, stimulations produced only a small head movement, but the whole behavioral sequence reappeared as soon as the animal awoke. In monkeys injected with chlorpromazine, the evoked behavior was inhibited in the same way as during spontaneous sleep, while the administration of atropine, Regitine, and Indurol which blocked both sympathetic and parasympathetic systems, produced only minor modifications of the sequential response.

SELF-PRESENTATION AND SELF-TERMINATION OF A CONFLICT-PRODUCING STIMULUS

Rats could press a lever to initiate or terminate a stimulus that was associated with intermittent rewards and punishments. Subjects spent time in both the stimulus-on and stimulus-off condition and oscillated frequently between the two conditions. This method provides continuous, quantitative records of oscillatory behavior and is sensitive to manipulations of shock intensity and food deprivation as well as the relative frequency of reward and punishment.

ILLUMINATION PREFERENCE OF ALBINO RATS IN A CLOSED HEXAGONAL MAZE

Ss were allowed to choose among 6 illumination conditions by altering their location in a maze. For a choice among 0 (darkness), 1, 2, 4, 8, and 16 ft.-candles in Exp. 1, preference decreased with increasing intensities. Ss tested during the dark portion of their cycle showed a stronger preference for darkness than Ss tested during the lighted portion of their cycle. In Exp. 2, preference for 0, .01, .1, 1.0, 10.0, and 25.0 ft.-candles was again inversely related to intensity, except that there was no difference between preference for darkness and .01 ft.-candles.