Perceptions have relative intensities {intensity, sense physiology} at locations.
coding
Axon-hillock membrane potential, axon current, average nerve-impulse rate, or neurotransmitter release can represent intensity.
receptors
Mechanical strains, temperature changes, chemical bonding, cell-hair vibration, and photon absorption change receptor membrane-molecule configurations. Configuration rearrangement changes molecule potential energy. Molecule steady-state configurations have lowest potential energy. Receptors transduce molecule potential-energy change into neurotransmitter-packet release at synapses onto neuron dendrites and cell bodies. Neurotransmitters open or close membrane ion channels to change synaptic neuron-membrane electric potential.
neurons
Synaptic membrane potentials spread to neuron axon hillock, where they add. Every millisecond, if hillock-membrane depolarization exceeds threshold, hillock membrane sends nerve impulse down axon.
threshold
Previous activity and neurohormones change neuron thresholds, so neurons detect current relative intensity, not absolute intensity. Perceptual intensities can be transient or sustained.
Small stimuli, such as gentle touch, can trigger sense response {irritability, sense}.
Sense receptors {sensory transducer} convert kinetic or potential energy from mechanical-force touch, temperature, and hearing translations and vibrations, or electrical-force light, liquids, or gases into cell-membrane depolarizations, whose electrical effects pass to neurons.
Machine computation is for stepwise analysis. Brain computation is for synthesis over time. Unlike computer programs, sensations can cause ongoing excitation {sustained response} at same location. Sustained responses are like steady states, not equilibrium states or transient states. Sustained responses use invariants and transformations to reach steady state. Neural assemblies have evolved to develop sustained responses. Sustained responses can serve as symbol grounds.
1-Consciousness-Sense-Physiology
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Date Modified: 2022.0225