For years, researchers have noted that many neurons in the prefontal cortex have “weird” properties. They respond to a wide range of seemingly unrelated unrelated information. These kitchen sink, “mixed selectivity” neurons were often ignored or dismissed because they didn’t seem to make sense (well, except to network modelers who knew about hidden units and support vector machines). Stokes et al recorded from multiple electrodes in the prefrontal cortex. This revealed shifting patterns of PFC activity that followed a trajectory through multi-dimensional space from signaling sensory events to internal factors like rules and decisions. Many PFC neurons participated in multiple states. Thus, mixed selectivity doesn’t result in cortical porridge but rather an orderly progression of mental states, provided you have multiple electrodes and can simultaneously take multiple neurons into account.
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Miller, E.K. and Fusi, S. (2013) Limber neurons for a nimble mind. Neuron. 78:211-213. View PDF »
About the Author
The Miller Lab uses experimental and theoretical approaches to study the neural basis of the high-level cognitive functions that underlie complex goal-directed behavior. ekmillerlab.mit.edu