Through these doors one may view the brain from the brain’s own point of view. The starting point for this labyrinth is several sets of “functional brain imaging” studies, or scans of brain metabolism during various tasks. Positron Emission Tomography, or PET, is the principle imaging technology, and most of the studies encompassed here have been archived in the Brainmap database at the University of Texas Research Imaging Center (http://ric.uthscsa.edu/).

The current state of the art in imaging thoughts: PET studies are detemined efforts to locate particular mental functions in particular regions of the brain. PET methods favor localization hypotheses. But a review of several hundred PET studies reveals that localized functions are the exception, not the rule. Instead, the brain generally employs distributed resources.

Multidimensional scaling and the space of mind: What then? If the brain is not a bureucracy of functional specialists, what is it? It is — in my view — a radical democracy. A cooperative kibbutz in which everyone pitches in a bit on just about everything. Or, in the language of cognitive science, the brain is a distributed processor. But distributed processors are hard to understand, requiring special interpretive strategies. One microscope of complexity is multidimensional scaling, and through its lenses we can see terra cognita, the space of mind.

Enter the Labyrinth, a virtual world defined by 34 PET experiments. The labyrinth itself is a three-dimensional map of 34 distributed patterns of activation reported in the PET literature. The motivation for this approach is discussed above, in “The current state of the art.” The approach itself uses multidimensional scaling, discussed just above. Distances between points in the labyrinth correspond to dissimilarities between patterns of activation. The labyrinth is color coded; with a little exploration you should be able to interpret the colors. The labyrinth is written in VRML 2.0 (Virtual Reality Modelling Language 2.0). Your browser might need a plug-in capable in VRML 2.0. After that you are free to explore the space of mind.

Discuss the Labyrinth