The dimensionality of episodic images

Previous studies (Doxas, Dennis, & Oliver, 2010) show that natural language discourse exhibits a two-scale structure with a lower dimension at short distances and larger dimension at long distances. We attempt to search for the source of this constraint in the visual input that goes into forming episodic experiences in human beings. This information is assumed to be approximated well by images captured by a MicrosoftTMResearch SenseCam that our subjects used. The hypothesis is that if the same two scale structure is observed here, the constraint is possibly not one that is imposed by the cognitive system. We use and contrast two methods by which images can be represented: the traditional color histogram and a more recently developed color correlogram method. The color correlogram is established to work better for our current purposes. We observe hints of a two scale structure in the correlation dimension plots but these are not conclusive.