Berlyne, D. E. (1958). The influence of complexity and novelty in visual figures on orienting responses. Journal of Experimental Psychology, 55(3), 289-296.

Undergraduate Ss were presented with a succession of pairs of visual figures, projected on a screen for 10 sec. each. Which figure was fixated first and how long each member of a pair was fixated were the data recorded. In Exp. I, one figure of each pair was "more complex" or, in information-theory language, higher in relative or absolute uncertainty than the other. Six different variables which may be regarded as forms of complexity were investigated separately. In all cases, significantly more time was spent looking at the "more complex" figure. In Exp. II, the same figure recurred on one side of the screen for a number of training trials, while a new figure appeared every time on the other side. The fixation time for the varying stimuli progressively increased at the expense of the fixation time for the recurring stimulus. During subsequent test trials, when new material appeared on both sides, Ss reverted to fixating both figures about equally. Which figure was fixated first bore no consistent relation to the independent variables. The implications of the findings are discussed in terms of psychological information theory and of behavior theory, with special reference to the relation between attention and perceptual curiosity.