IRCS Conference Room
Department of Cognitive Biology
University of Vienna
Dendrophilia and Human Cognition
A fundamental observation about human cognition is that we make “infinite use of finite means,” using a limited number of rules and principles to generate unbounded sets of behaviors and to recognize unbounded sets of patterns. In many cases this involves a capacity to both generate and perceive tree structures in stimuli of various types (language, music, social cognition, etc.). Human language in particular requires computational resources that go beyond simple string generation to allow the inference and generation of complex, flexible tree structures. This entails supra-regular (above finite state) computational mechanisms that augment standard finite state mechanisms with a flexible, multi-purpose memory store (a "stack" or equivalent). I review comparative research gathered over the past decade suggesting that such computational resources are poorly developed or absent in most nonhuman animal species. This body of empirical research implies that the human proclivity for producing and perceiving tree-structured stimuli -- our "dendrophilia" -- represented a key cognitive innovation during recent human evolution. Both brain imaging and comparative research suggest that Broca's area (Brodmann Areas 44 and 45) is an important computational hub for human tree processing, suggesting that this core prefrontal region was harnessed, and its computational role expanded, during the evolution of dendrophilia and human cognitive abilities in general.