Visual complexity has been known to be a significant predictor of preference for artistic works for some time. The first study reported here examines the extent to which perceived visual complexity in art can be successfully predicted using automated measures of complexity. Contrary to previous findings the most successful predictor of visual complexity was Gif compression. The second study examined the extent to which fractal dimension could account for judgments of perceived beauty. The fractal dimension measure accounts for more of the variance in judgments of perceived beauty in visual art than measures of visual complexity alone, particularly for abstract and natural images. Results also suggest that when colour is removed from an artistic image observers are unable to make meaningful judgments as to its beauty.

Here we report the results of an experiment carried out with magnetoencephalography which shows that the prefrontal area is selectively activated in humans during the perception of objects qualified as ''beautiful'' by the participants. Therefore, aesthetics can be hypothetically considered as an attribute perceived by means of a particular brain processing system, in which the prefrontal cortex seems to play a key role.

By means of extensive computer simulations, the authors consider the entangled coevolution of actions and social structure in a new version of a spatial Prisoners Dilemma model that naturally gives way to a process of social differentiation. Diverse social roles emerge from the dynamics of the system: leaders are individuals getting a large payoff who are imitated by a considerable fraction of the population, conformists are unsatisfied cooperative agents that keep cooperating, and exploiters are defectors with a payoff larger than the average one obtained by cooperators. The dynamics generate a social network that can have the topology of a small world network. The network has a strong hierarchical structure in which the leaders play an essential role in sustaining a highly cooperative stable regime. But disruptions affecting leaders produce social crises described as dynamical cascades that propagate through the network.

Although a number of studies have verified Daniel Berlyne's (1971) predicted maximum preference for intermediately complex stimuli, others have found that preference increased or decreased in relation to complexity. The objective of the present work was to assess whether differences in the kinds of stimuli used in prior studies or in the way complexity was defined could explain this divergence. In the first phase a set of 120 stimuli varying in complexity, abstraction, and artistry was assembled. In the second phase 94 participants were asked to rate the beauty of the stimuli. In the final phase the same participants rated 60 of the stimuli on seven complexity dimensions. We failed to detect any meaningful influence of complexity on beauty ratings for any of the kinds of stimuli. However, our results suggest that there are three different forms of complexity that contribute to people's perception of visual complexity: one related with the amount and variety of elements, another related with the way those elements are organized, and asymmetry. We suggest that each of these types of complexity influences beauty ratings in different ways, and that the unresolved relation between complexity and beauty appreciation is mainly due to differences in the conception, manipulation, and measurement of visual complexity.