Chapter_15 - Nervous System

Chapter 15: Nervous System and Behavioural Health

Central Nervous System (CNS)

• Components: Brain and Spinal Cord.

• Function: Controls body functions; allows thinking, memory, speech, and movement.

• Cauda Equina: Bundle of spinal nerves at the lower end of the spinal cord.

Functions of Nervous System

• Communication System: Coordinates all body functions.

• Divided into Two Parts:

  • Somatic Nervous System:

    • Sends signals to skeletal (voluntary) muscles.

    • Receives sensory input.

  • Autonomic Nervous System:

    • Functions subconsciously; controls involuntary actions (smooth and cardiac muscles).

    • Evaluates sensory information and sends responses to muscles/glands.

Peripheral Nervous System (PNS)

• Components: Cranial nerves (12 pairs) and spinal nerves (31 pairs).

• Function: Acts as electrical wires for communication between CNS and muscles/sensory receptors; controls automatic functions (e.g., heart, respiration).

Brain Structures

• Cerebrum: Largest part; controls voluntary muscle movement, senses (sight, sound), intellect, memory, emotions.

• Cerebellum: Coordinates muscle movements and maintains balance.

• Ventricles: Cavities containing cerebrospinal fluid (CSF) that cushions and nourishes the brain.

Brainstem Components

• Parts: Pons, Medulla Oblongata, Midbrain.

• Functions: Controls respiration and heart rate, connects cerebrum with the spinal cord.

Meninges

• Definition: Three protective membranous layers around brain/spinal cord (Dura mater, Arachnoid mater, Pia mater).

• Functions: Provides mechanical protection, supports blood vessels, allows passage of CSF.

Spinal Nerves

• Total: 31 spinal nerves connecting spinal cord to body.

• Categories:

  • Cervical: 8 pairs - head, neck, diaphragm.

  • Thoracic: 12 pairs - chest and abdominal muscles.

  • Lumbar: 5 pairs - leg muscles.

  • Sacral: 5 pairs - bowel, bladder, sexual function.

Neurons and Glia

• Neurons: Nerve cells that conduct impulses.

• Glia: Support and nourish nerve tissue; maintain the structure of the Nervous system.

Disease and Disorder Terms

• Examples:

  • Glioblastoma: Tumor of developing glia.

  • Subdural Hematoma: Accumulation of blood below the dura mater, often from injury.

Brain Diseases and Disorders

• Dementia Types:

  • Alzheimer’s Disease: Most common; irreversible cognitive decline.

  • Vascular Dementia: Due to small strokes.

  • Frontotemporal Dementia: Behavior and speech impacts.

• Movement Disorders:

  • Cerebral Palsy: Muscle control dysfunction due to brain damage.

  • Multiple Sclerosis: Degeneration of nerve fibers.

  • Parkinson's Disease: Affects movement and cognition.

Stroke and Its Causes

• Types: Ischemic (blood supply restricted), Hemorrhagic (vessel rupture).

• Warning Signs: Transient Ischemic Attack (TIA) - temporary stroke-like symptoms.

Other Conditions

• Shingles: Painful rash from reactivated chickenpox virus.

• Diagnostic Procedures: EEG, CT, MRI used for evaluating brain conditions.

Behavioral Health Terms

• Disorders:

  • Anxiety Disorders: Chronic feelings of apprehension.

  • Bipolar Disorder: Mood swings between mania and depression.

  • Schizophrenia: Severe mental disorder with hallucinations.

  • PTSD: Symptoms relating to traumatic events.

Combining Forms, Prefixes, and Suffixes

• Combining Forms:

  • Neuro- (nerve, nervous system)

  • Encephal/o- (brain)

  • Myel/o- (spinal cord)

  • Psych/o- (mind)

  • Gli/o- (glial cells)

  • Cerebell/o (cerebellum)

  • Cerebr/o (cerebrum, brain)

  • Dur/o (hard, dura mater)

  • Gangli/o (ganglion)

  • Ganglion/o - (ganglion)

  • Mening/o - (meninges)

  • Meningi/o - (meninges)

  • Poli/o - (Gray Matter)

  • Radicul/o - (nerve root)

  • Rhiz/o - (nerve root)

  • Angi/o - (vessels, blood vessels)

  • Blast/o - (developing cell, germ cell)

  • Cephal/o - (head)

  • Crani/o - (cranium)

  • Embol/o - (plug)

  • Esthesi/o - (sensation, sensitivity, feeling)

  • Hem/o - (blood)

  • Hemat/o - (blood)

  • Hydr/o - (water)

  • Ment/o - (mind)

  • Mon/o - (one, single)

  • Phas/o - (speech)

  • Psych/o - (mind)

  • Quadr/i - (four)

  • Thromb/o - (blood clot)

• Prefixes:

  • Peri- (around)

  • A- (absence of, without)

  • An- (Absence of, without)

  • Dys- (painful, abnormal, difficult)

  • Hemi- (half)

  • Hyper- (above, excessive)

  • Inter- (between)

  • Intra- (within)

  • Pera- (beside, beyond, around, abnormal)

  • Poly- (many, much)

  • Post- (after)

  • Sub- (under, below)

  • Contra- (against)

  • Pre- (before)

• Suffixes:

  • -itis (inflammation)

  • -a (no meaning)

  • -al (pertaining to)

  • -algia (pain)

  • -cele (hernia, protrusion)

  • -genic (producing, originating)

  • -graphy (process

  • -oma (tumor)

  • -pathy (disease)

  • -plasia (growth)

  • -pnea (breathing)

  • -logy (study of)

  • -ectomy (surgical removal)

  • -scopy (visual examination)

  • -gram (record)

  • -rrhea (flow)

  • -phobia (fear)

  • -mania (excessive enthusiasm)

  • -dysfunction (impaired function)