Divisions of the Human Nervous System

Divisions of the Human Nervous System

The nervous system in humans can be divided into (1) the Central Nervous System (CNS) and (2) the Peripheral Nervous System (PNS).

The human nervous system can be divided into two major divisions: the central nervous system (CNS) and the peripheral nervous system (PNS).

Central Nervous System (CNS)

  • The CNS consists of the brain and spinal cord, and it serves as the main control center for the entire nervous system. The brain is responsible for processing and integrating sensory information, initiating voluntary movements, and regulating various physiological functions. The spinal cord acts as a pathway for transmitting signals between the brain and the rest of the body, and it also controls some reflex actions independently of the brain.

Peripheral Nervous System (PNS)

  • The PNS includes all the nerve cells and fibers outside of the CNS. It is further divided into two sub-divisions: Somatic Nervous System (SNS) and Autonomic Nervous System (ANS).

a. Somatic Nervous System (SNS)

  • The SNS is responsible for transmitting sensory information from the sensory organs (such as skin, eyes, ears, etc.) to the CNS and for carrying motor signals from the CNS to the voluntary muscles. It controls conscious and voluntary movements, allowing us to interact with our environment.

b. Autonomic Nervous System (ANS)

  • The ANS regulates involuntary functions and maintains internal homeostasis. It controls various internal organs and glands, regulating processes such as heart rate, digestion, respiratory rate, and glandular secretions. The ANS itself is further divided into two branches:

  • Sympathetic Nervous System: Responsible for the "fight or flight" response, which prepares the body for stress or emergencies by increasing heart rate, dilating pupils, and redirecting blood flow to essential organs.

  • Parasympathetic Nervous System: Responsible for the "rest and digest" response, which promotes relaxation and recovery by slowing down heart rate, constricting pupils, and enhancing digestion.

The central nervous system (CNS) and the peripheral nervous system (PNS) work in coordination to allow the human body to function, respond to stimuli, and maintain internal balance (homeostasis).

Key Points

  • The Central Nervous System (CNS) contains the brain and spinal cord.

  • The Peripheral Nervous System (PNS) contains everything outside, or "peripheral" to, the brain and spinal cord such as cranial nerves, spinal nerves, and the autonomic nervous system.


Psychopharmacology Review Course

Buy nowLearn more

Introduction to Pharmacology and Psychopharmacology

  • What is Pharmacology?
  • General Mechanisms in Psychopharmacology
  • Overview of Psychopharmacological Treatments
  • Overview of Drug Development
  • Clinical Trials (Phases I-IV)
  • Drug Patents, Generic Drugs, Orphan Drugs, and Expedited Reviews

The Basics of Studying Drugs and Medications

  • What is Pharmacokinetics and Pharmacodynamics?
  • Pharmacokinetics: Routes of Administration
  • Pharmacokinetics: A-D-M-E
  • Pharmacokinetics: Absorption
  • Pharmacokinetics: Distribution
  • Pharmacokinetics: Concentration-Time Curves
  • Pharmacokinetics: Steady State
  • Pharmacokinetics: Metabolism
  • Pharmacokinetics: Elimination Half-Life
  • Pharmacokinetics: Drug Clearance and Elimination Kinetics
  • Pharmacodynamics: Dose-Response Curves
  • Pharmacodynamics: Agonists, Partial Agonists, Antagonists, and Inverse Agonists

Genetics

  • What is Genetics?
  • The Central Dogma of Biology
  • What is Deoxyribonucleic Acid (DNA)?
  • Altering DNA, Mutations, and Epigenetics
  • What is Ribonucleic acid (RNA)?
  • Terms, Definitions, Laboratory Techniques, and Types of Genetic Studies

Medications for Anxiety Disorders

  • Rapid Review of Anxiety Disorders
  • Anxiolytics

Medications for Psychotic Disorders

  • Psychosis
  • Rapid Review of Psychotic Disorders
  • Antipsychotics1

Medications for Attention Deficit Hyperactivity Disorder (ADHD)

  • Psychostimulants
  • Nonstimulants, Modafinil, and Armodafinil

Medications for Mood Disorders

  • Mood, Affect, and Mood Disorders
  • Rapid Review of Depressive Disorders
  • Historical Background of Antidepressants
  • Selective Serotonin Reuptake Inhibitors (SSRIs)
  • Serotonin Norepinephrine Reuptake Inhibitors (SNRIs)
  • Norepinephrine Dopamine Reuptake Inhibitors (NDRIs)
  • Serotonin Receptor Partial Agonists (SPARIs) & Serotonin Receptor Antagonists (SARIs)
  • Norepinephrine Receptor Antagonists and Agonists
  • Monoamine Oxidase Inhibitors (MAOIs)
  • Tricyclic Antidepressants (TCAs)
  • Ketamine1
  • Rapid Review of Bipolar Disorders
  • Mood Stabilizers
  • Lithium
  • Valproic Acid (Depakote)
  • Lamotrigine (Lamictal)
  • Carbamazepine (Tegretol)
  • Oxcarbazepine (Trileptal)
  • Topiramate (Topamax)

Basic Neuroscience Principles

  • Divisions of the Human Nervous System
  • Neurons and Glial Cells
  • Autonomic Nervous System
  • Neurotransmitters
  • Receptors
  • Signal Transduction
  • Neurotransmitter Systems
  • Membrane Potentials and Action Potentials
  • The Synapse

Medications for Cognitive Disorders (e.g. Dementia)

  • Neurobiology of Memory
  • Dementia and Cognitive Enhancers
  • L-Dopa and Parkinson Disease

Medications for Pain

  • Neurobiology of Pain
  • Opioids and the Treatment of Pain

Addiction and Drug Abuse

  • What is Addiction?
  • Sobering Statistics (Pun Intended)
  • Terms and Definitions
  • Reasons people use and misuse drugs
  • Dopamine, Mesolimbic Pathway, and the Neurobiology of Addiction
  • From Pleasure to Compulsion
  • Alcohol (Ethanol)
  • Nicotine
  • Marijuana (Cannabis)
  • Psychostimulants
  • Opioids (Heroin)
  • Methanol and Ethylene Glycol

Prescribing Psychiatric Medications in Medically Complex Patients

  • Psychopharmacology in Medical Illnesses (PDF)
  • QTc Prolongation and Psychotropic Medications
  • General Psychopharmacology Facts Every Prescriber Should Know

References

  • References for this course

Psychopharmacology Review Questions

  • REVIEW QUESTIONS AND ANSWERS (PDF)