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.

Consciousness a Convolution of the Perceptual Mental Image with the Sense-of-Self

Link to —  Homunculus (Topographic) Diagram

Link to —  Spinal Cord Diagram

Link to —  Cortical Layers Diagram

 

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.

 

Research Study — Taste System Fidelity of Signaling

Research Study — Cognitive Processes Influence on Pain Perception

Research Study — Somatosensory Channel for Irritants

Research Study — Cortical Connectivity and Sensory Coding

Research Study — Touch Receptors Tuned by Epidermal Merkel Cells

Research Study — Sensory Stimulation Shifts Visual Cortex from Synchronous to Asynchronous

Research Study — Itch Sensation

Research Study — Itch Responses

 

Associative property of memory typically excites a Multimodal Reaponse

A whiff of perfume from a long-ago romance can reignite long-forgotten memories. Via associative property of memory, sensory input neural traces, which overlap synaptic connections for memory traces, cue multimodal memory reactivations.

Insula maps internal feelings from your body

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)

Hands and Mouth

The hands and the mouth have an enormous, vastly disproportionate representation in somatosensory cortex. (Greenfield; Human Brain, 43)

Cutaneous Receptors

Three important cutaneous receptors (diagram)  (Fix; High-Yield Neuroanatomy, 35)

Free nerve endings mediate pain and temperature sensation. (Fix; High-Yield Neuroanatomy, 35)

Messier corpuscles of the dermal papillae mediate tactile two-point discrimination. (Fix; High-Yield Neuroanatomy, 35)

Pacinian corpuscles of the dermis mediate touch,    pressure,    and vibration sensation. (Fix; High-Yield Neuroanatomy, 35)

Link to — Skin Neurons (diagram)

 

Sensory Mergers in Temporal and Parietal Association Areas before Prefrontal Convergence

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. (Llinas, Mind-Brain Continuum; 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)

 

Link to — Hierarchical Organization of Memory Networks

 

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)

 

Sense of Self

Link to — Self Diagram

Vision

Vision

Link to — Visual Pathways Eye

Auditory

Auditory System

Link to — Auditory Pathways

Somatosensory

Link to — Homunculus (Topographic) Diagram

Link to — Spinal Cord Diagram

Olfactory

Research Study — Olfactory Perception of Odor Molecules from Chemical Features

Research Study — Olfactory Stimuli Discrimination

Link to — Olfactory Pathways

Gustatory

Link to — Orbitofrontal Cortex Functions

Vestibular

Link to — Vestibular Pathways