Nervesignaler

Nervesignaler, also known as nerve impulses or action potentials, are the fundamental means by which information is transmitted within the nervous system. They are rapid changes in the electrical membrane potential of a neuron that travel along the axon and are converted into chemical signals at synapses. The generation of a nerve signal involves the coordinated opening and closing of voltage‑gated ion channels. A resting neuron has a negative interior relative to the outside, maintained by sodium‑potassium pumps. When stimulated, sodium channels open, allowing Na⁺ influx and depolarization. Once the membrane potential crosses a threshold, potassium channels open, restoring the negative potential during repolarization. This sequence constitutes the action potential, which is all-or-none; it propagates without losing amplitude due to the passive and active cable properties of the axon.

At the axon terminal, the depolarising wave triggers the release of neurotransmitters from synaptic vesicles into the synaptic cleft. These chemical messengers bind to receptors on the postsynaptic membrane, producing either excitatory or inhibitory responses that modulate the activity of downstream neurons. Nerve signals enable sensory perception, motor control, autonomic regulation, and higher cognitive functions.

Disruptions in the generation or propagation of nervesignaler are implicated in diverse neurological disorders. Paraplegia and multiple sclerosis involve demyelination or loss of axonal integrity, impairing conduction velocity. Epilepsy arises from hyperexcitable neuronal networks. Understanding the biophysics of nervous system signalling remains central to both basic neuroscience research and clinical intervention strategies.