ectopic spike
An action potential that originates from an abnormal location along the axon rather than the normal initiation site.
Full Definition
Ectopic spikes are action potentials that arise from sites along the axon other than the typical initiation zone near the axon hillock. These abnormal spikes can occur due to local membrane damage, altered ion channel expression, mechanical pressure, or pathological conditions. Ectopic activity is implicated in neuropathic pain, peripheral nerve disorders, and various neurological conditions where normal spike initiation is disrupted. Understanding ectopic spike generation is important for interpreting abnormal neural recordings and appears in literature on nerve pathology, pain mechanisms, and axonal dysfunction.
Usage
Usage note: Distinguish from antidromic spikes, which originate normally but travel in the reverse direction.
In Context
- "Ectopic spikes generated along the damaged axon contributed to chronic pain symptoms." — Neuropathology research paper
- "The recordings showed multiple ectopic spike initiation sites in the peripheral nerve." — Clinical neurophysiology report