Population coding of orientation in the visual cortex of alert cats--an information theoretic analysis.
We studied the encoding of stimulus orientation in the visual cortex of alert animals using information theory methods. Based on a labeled-line code, the encoding of orientation was mostly synergistic and only few pairs coded redundant. The synergy contributed about 20% of the information and was strongest for sites with distinct tuning curves. A recently proposed decomposition of synergy revealed that redundancy introduced by common tuning preferences is more than just compensated by noise correlations which mostly contributed synergistically. Based on a pooled response code, the contribution of noise correlations diminished resulting in a severe information loss. Thus, to operate economically, cortical neurons should either employ a labeled-line code or, if using pooled responses, be highly selective in choosing afferents.
Kayser
Christoph
C
Institute for Neuroinformatics, University/ETH Zürich, Switzerland. kayser@tuebingen.mpg.de
König
Peter
P
D000818:Animals; D002415:Cats; D007257:Information Theory; D016571:Neural Networks, Computer; D009949:Orientation / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology*