1. ALEXANDER, M., & ISAAC, W. 1965 Effect of illumination and d-amphetamine on the activity of the rhesus macaque. Psychol. Rep., 16, 311-313.
2. BERLYNE, D. E. 1960 Conflict, arousal, and curiosity. New York: McGraw-Hill.
3. BERLYNE, D. E. 1969 The reward-value of indifferent stimulation. In Tapp, J. T.(Ed.) Reinforcement and Behavior. New York and London: Academic Press, pp.178-214.
4. BERLYNE, D. E., KOENIG, I. D. V., & HIROTA, T. 1966 Novelty, arousal, and the reinforcement of diversive exploration in the rat. J. comp. physiol. Psychol., 62, 222-226.
5. BINDRA, D., & BARAN, D. 1959 Effects of methylphenidate and chlorpromazine on certain components of general activity. J. exp. anal. Behav., 2, 343-350.