Neurologic System Overview

These flashcards cover key vocabulary and concepts related to the neurologic system, as discussed in the lecture.

Central Nervous System (CNS)

Consists of the brain and spinal cord; responsible for organizing and analyzing information.

Peripheral Nervous System (PNS)

Connects the CNS to the limbs and organs; divided into cranial nerves and spinal nerves.

Afferent nerves

Sensory nerves that carry stimuli to the CNS for processing.

Efferent nerves

Nerves that carry commands from the CNS to the effector organs.

Somatic Nervous System

Regulates voluntary motor control of skeletal muscle.

Autonomic Nervous System

Regulates involuntary control of internal organs; comprises sympathetic and parasympathetic divisions.

Sympathetic Nervous System

Part of the autonomic system that triggers the 'fight or flight' response.

Parasympathetic Nervous System

Part of the autonomic system that promotes 'rest and digest' activities.

Neurons

Cells that are the primary information and communication units in the nervous system.

Dendrites

Short, branched extensions of neurons that receive impulses from other neurons.

Axon

The long, slender part of a neuron that carries nerve impulses away from the cell body.

Myelin Sheath

Insulating layer around an axon that speeds up nerve impulse propagation.

Nodes of Ranvier

Gaps in the myelin sheath that facilitate faster nerve conduction through saltatory conduction.

Neurolglial Cells

Supportive cells in the nervous system that assist neurons and maintain homeostasis.

Reflex Arc

A neural pathway that controls reflex actions, allowing for faster responses without brain involvement.

Upper Motor Neurons

Neurons in the CNS that directly influence lower motor neurons and refine reflexes.

Lower Motor Neurons

Neurons that have a direct effect on muscles and enable movement.

Cerebrospinal Fluid (CSF)

Clear fluid that protects the brain and spinal cord; produced in the ventricles by the choroid plexus.

Blood-Brain Barrier

A selective barrier that prevents certain substances from entering the brain tissue.

Cranial Nerves

Twelve pairs of nerves that primarily control sensory and motor functions of the head and neck.

Spinal Nerves

Thirty-one pairs of mixed nerves that emerge from the spinal cord and supply the body with motor and sensory information.

Dermatome

An area of skin primarily supplied by a single spinal nerve root.

Synapse

The junction between two neurons where impulses are transmitted.

Neurotransmitters

Chemical messengers released by neurons to transmit signals across synapses.

Action Potential

A rapid change in membrane potential that propagates along the axon, leading to nerve impulse transmission.

Saltatory Conduction

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

Hindbrain

Part of the brain that includes the cerebellum, pons, and medulla oblongata, responsible for vital functions.

Forebrain

The most advanced part of the brain, consisting of the cerebral cortex and subcortical structures.

Limbic System

Regulates emotions and long-term memory, closely connected to the hypothalamus.

Basal Ganglia

Group of structures involved in the coordination of voluntary movements.

Diencephalon

Part of the forebrain that includes structures such as thalamus and hypothalamus, responsible for sensory and autonomic functions.