In their article, Is the Brain a Quantum Computer,? Litt, Eliasmith, Kroon, Weinstein, and Thagard (2006) criticize the Penroseâ€œHameroff Orch OR quantum computational model of consciousness, arguing instead for neurocomputation as an explanation for mental phenomena. Here I clarify and defend Orch OR, show how Orch OR and neurocomputation are compatible, and question whether neurocomputation alone can physiologically account for coherent gamma synchrony EEG, a candidate for the neural correlate of consciousness. Orch OR is based on quantum computation in microtubules within dendrites in cortex and other regions linked by dendriticâ€œdendritic gap junctions (dendritic webs) acting as laterally connected input layers of the brainâ„¢s neurocomputational architecture. Within dendritic webs, consciousness is proposed to occur as gamma EEG-synchronized sequences of discrete quantum computational events acting in integration phases of neurocomputational integrate-and-fire cycles. Orch OR is a viable approach toward understanding how the brain produces consciousness.
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