Neurology Basics Overview

Study Notes

Somatic Motor Neurons

Contribute to voluntary muscle movement by transmitting signals from the central nervous system (CNS) to skeletal muscles.
Control activities such as walking, running, and other intentional movements.

Astrocytes

Serve as the primary support cells in the CNS, contributing to the blood-brain barrier, which regulates the passage of substances between blood and neurons.
Maintain the extracellular environment by regulating ion balance and providing nutrients to neurons.

Microglia

Act as the immune cells of the nervous system, responding to injury and disease.
Remove debris, dead cells, and pathogens through phagocytosis, thereby playing a crucial role in neuroinflammation and repair.

Gray Matter

Appears gray due to the presence of numerous neuronal cell bodies and unmyelinated axons, which contrasts with myelinated white matter.
Contains synapses and is involved in processing and integrating information.

Oligodendrocytes

Responsible for the formation of myelin sheath in the CNS, which insulates axons and speeds up action potentials.
Support neuronal health and function by providing structural support.

Interneurons

Located primarily in the CNS, especially within the spinal cord and brain.
Function as relay points between sensory and motor neurons; they process and integrate information, facilitating reflexes and complex behaviors.

Schwann Cells

Responsible for the formation of myelin sheaths around axons in the peripheral nervous system (PNS), ensuring fast signal transmission.
Aid in the regeneration of damaged nerves through the release of growth factors.

Satellite Cells

Found surrounding neuronal cell bodies in ganglia of the PNS.
Provide structural support and help regulate the microenvironment by controlling the exchange of nutrients and waste.

Sodium-Potassium Pump

Maintains the resting membrane potential of neurons by transporting sodium ions out of and potassium ions into the cell.
Essential for neuronal excitability and muscle contraction, contributing significantly to the generation of action potentials.

Graded Potentials vs. Action Potentials

Graded potentials are small, variable changes in membrane potential that occur in response to stimuli; they can summate and spread over short distances.
Action potentials are rapid, all-or-nothing depolarizations of the membrane that occur when a threshold is reached, propagating signals over long distances.

Neurilemma

The outermost layer of the Schwann cell that encompasses the myelin sheath around a PNS axon.
Plays a key role in nerve regeneration and repair by guiding the growth of new axons after injury.

Description

This quiz provides an overview of basic concepts in neurology including motor neurons, interneurons, and neuroglia. It covers the functions and characteristics of different types of neurons as well as the role of neuroglia in the nervous system.