Apical amplification-a cellular mechanism of conscious perception?
Neuroscience of Consciousness January 1, 2021 Tomáš Marvan, Michal Polák, Talis Bachmann et al.
A theoretical account proposes that conscious perceptual experience depends on a specific cellular mechanism in the neocortex: apical amplification. Inputs to apical dendrites in layer 1 of many neocortical neurons integrate diverse contextual signals, which then amplify the transmission of sensory information arriving at the cell's basal synapses. This context-sensitive amplification makes perception more flexible and adaptive. The mechanism offers a way to implement recurrent processing without strong loops, supports global broadcasting while preserving individual cell contributions, and contributes to integrated information theory's holistic aspects. Because apical amplification relies on neuromodulators like acetylcholine and amines, it links specific conscious contents to global mental states and arousal fluctuations. The authors conclude that apical dendrites provide a cellular basis for the context-sensitive selective amplification necessary for conscious perception.