Fig. 4

Formation of C-semblance for consciousness and the role of oscillating potentials. Spontaneous activity occurring during events such as dendritic spikes occurring at the islets of inter-LINKed postsynapses (IILPS) can lead to semblance at all the postsynapses that are activated thorough the LINKs (in the absence of arrival of activity from their presynaptic terminals). In addition, reactivation of large number of scattered single inter-postsynaptic functional LINKs (B–D) within the cortices also induce semblances. Background sensory stimuli both from within the body (respiration and heart beat) and from the environment reactivate several inter-postsynaptic functional LINKs and also induce semblances. The net result of all the semblances induced at the postsynapses lead to C-semblance for consciousness. C-semblance is a function of (a) the reactivated inter-postsynaptic LINKs that in turn is a function of existing innate inter-postsynaptic LINKs, (b) some of the acquired inter-postsynaptic LINKs induced by associative learning during life that are reactivated during oscillation of potentials and (c) the complexity of the nervous system of a given species. The synaptic transmission between vertically oriented neuronal orders provides vertical component and the lateral spared of potentials among the postsynapses during dendritic spikes provide horizontal component that lead to surface or extracellular recorded oscillating potentials. These oscillating potentials eventually give rise to neuronal firing (somatic spikes) in an oscillating manner (shown by a wave-form). Additional factors that provide components for oscillations include recurrent collaterals, laterally connected layer 1 neurons, cortico-thalamo-cortical connections and activity arriving from the thalamus (in response to background sensory stimuli) and the brain stem (connections with respiratory drive). When frequency of oscillating potentials changes, the nature of consciousness will change (example, in sleep). C C-semblance, Cs subjective changes to C-semblance due to contributions of semblances induced through reactivation of inter-postsynaptic functional LINKs formed by different associative learning events during life. P–Q Represents background sensory inputs. Wave shape Represents oscillating pontentials. A Presynaptic terminal where inputs from oscillatory neuronal activity arrives. B Postsynaptic terminal of the synapse A–B. D Postsynaptic terminal which is functionally LINKed to the postsynaptic terminal B. B–D Inter-postsynaptic functional LINK. Corresponding presynaptic terminal of postsynapse D is not shown. N Neurons that are firing. P–Q Represents background sensory inputs arriving at the nervous system either from the environment or from the body such as respiration and heartbeat. IILPS Islet of inter-LINKed postsynapses (Figure modified from Vadakkan 2010)