Role of Myelin and Multiple Sclerosis Overview

Flashcards summarizing key vocabulary terms related to the role of myelin and the pathology of Multiple Sclerosis.

Myelin

A fatty substance that surrounds the axons of some neurons, increasing the speed of electrical signals.

Nodes of Ranvier

Gaps in the myelin sheath where ion channels are located, allowing action potential regeneration.

Saltatory conduction

The process by which action potentials jump from one node of Ranvier to another, increasing conduction speed.

Multiple Sclerosis (MS)

An autoimmune disorder where the immune system attacks the myelin sheath, leading to scar formation.

Sclerosis

Scar tissue formation that occurs in multiple areas due to the loss of myelin in MS.

Plaques

Areas of damage in the myelin sheath, commonly associated with Multiple Sclerosis.

Relapsing Remitting MS

A form of MS characterized by clear episodes of symptom flare-ups followed by periods of remission.

Chronic Progressive MS

A form of MS that steadily worsens over time without clear relapses.

Environmental influences on MS

Factors such as geographic location that can affect the likelihood of developing Multiple Sclerosis.

Symptoms of MS

Common symptoms include cognitive dysfunction, fatigue, dizziness, motor issues, and sensory changes.

Epidemiology of MS

The study of how Multiple Sclerosis is distributed across different populations globally.

Genetic influence on MS

Factors that suggest a hereditary risk, with increased susceptibility if a relative has the disease.

Action potential speed

The speed at which an electrical signal is conducted along a neuron, influenced by axon diameter and myelination.

Thick myelinated axon speed

Approximately 100 meters/second or 224 mph.

Thick unmyelinated axon speed

Approximately 10 meters/second or 22.4 mph.