Giuseppe Vitiello has been working with W. J. Freeman to relate the properties of many-body systems to cognition.
http://www.archive.org/details/Redwood_Center_2007_01_23_Giuseppe_Vitiello
Here is a paper on possible relationships between quantum theory, symmetry breaking, and chaotic classical Hamiltonians:
http://www.sbfisica.org.br/bjp/files/v35_351.pdf
I am interested in this relationship between quantum properties, symmetry breaking, and chaos. If nothing else because grammar can be seen as symmetries in text, and my whole thesis is that grammar behaves in some ways like a quantum object.