Scientific Understanding of Consciousness
Consciousness as an Emergent Property of Thalamocortical Activity

Sensory Input

The brain's neural network is a network of neurons connected by synapses with synaptic efficacies established by genetics and continuously modified by ongoing experience.

Sensory input for the neural network is a multimodal input of the five senses activating millions of neurons in ever changing spatial and temporal patterns.

A sensory input pattern propagates into the brain's established synaptic efficacies pattern, activating a pattern of synaptic efficacies closely conforming to the sensory input pattern.

Feedforward inhibition serves to impose a temporal framework on a target area on the basis of inputs received. (Andersen; Hippocampus Book, 299)

The brain’s neural mechanisms respond to this activated pattern of synaptic efficacies, resulting in perception, consciousness, inscribing synaptic memory, and all of the other functions.

The insula maps internal feelings from your body. (Ramachandran; Tell-Tale Brain, 98)

The insula receives continuous streams of sensation from receptor cells in your heart, lungs, liver, viscera, bones, joints, ligaments, fascia, and muscles, as well as from specialized receptors in your skin that sense heat, cold, pain, sensual touch, and perhaps tickle and itch. (Ramachandran; Tell-Tale Brain, 98)

Insular cortex, shown in several coronal sections (diagram)  (Kandel; Principles of Neural Science, 332)

Vision, audition, and somatosensation merge in temporal and parietal association areas of the neocortex well before the common paths into the entorhinal cortex, amygdala, and prefrontal convergence sites. (Eichenbaum; Olfactory Perception and Memory, 180)

Pyramidal neurons of each primary sensory area -- V1 for vision, A1 for audition, S1 for somesthesis -- send axonal connections onto adjacent or nearby areas of somewhat different cytoarchitecture that constitute further processing steps for analysis within that modality. (Fuster; Cortex and Mind, 67)

Each successive area of the posterior cortical pathways for three major sensory modalities -- somatosensory, vision, and audition -- send collateral efferent connections to a progressively more rostral frontal area; all such connections are reciprocated by others in the opposite direction. (Fuster; Prefrontal Cortex, 359)

Ultimately it is function and usage that create the system of multiple interconnected networks for representation and classification of sensory information. (Fuster; Memory in Cerebral Cortex, 95)

The memory recalled in response to a fragment is that stored in the memory that is closest in pattern similarity. (Rolls & Treves; Neural Networks, 46)

Vision

Visual perception is formed in a hierarchy of neuronal assemblies extending from the primary visual areas of posterior cortex, through the association areas of parietal cortex, the interpretive areas of temporal cortex, and into the frontal cortex. Perception is associated with sparse but widespread neural activity in the higher levels of the ever widening receptive fields this visual hierarchy. Visual memory is mediated by synaptic plasticity in the sparse but widespread neural activity patterns in the higher association cortex.

 

Audition and Speech

Hierarchy of three pathways in series through which auditory information passes on its afferent journey through the CNS. (1) Reticular formation,  (2) Thalamus, (3) Cortex.  (Schneck & Berger; Music Effect, 86)

 

Somatosensory

 

Research Study — Sense of Touch

 

Pain Neural Pathways diagram

 

 

Taste

 

Olfactory

Taste and olfactory inputs converge in the orbitofrontal cortex of the frontal lobes, producing in a subjective flavor representation.

Flavor representation -- of taste and olfactory inputs in. (Rolls; Memory, Attention, and Decision-Making, 151)

 

Convergence-Divergence Zones and Working Memory

The association cortex areas of sensory processing will involve the functionality of Damasio's Convergence-Divergence Zone architecture.

The working memory model of Baddeley will function together with Fuster’s Perception-Action Cycle.

 

 

Return to — Sense-of-Self

Hierarchical Organization of Memory Networks

(Joaquín Fuster; The Prefrontal Cortex, 339)