Nervous System Overview

• CENTRAL
  • Brain
    • Forebrain
    • Midbrain
    • Hindbrain
  • Spinal Cord
    • Cervical
    • Thoracic
    • Lumbar
    • Sacral
• PERIPHERAL
  • Somatic
    • Efferent/Motor: primary motor cortex glutamatergic UMNs > corticospinal tract > anterior horn cholinergic alpha motor neurons (LMNs) > ventral roots > peripheral nerves > nAChRs on skeletal muscles
    • Afferent/Sensory: peripheral sensory receptors > peripheral nerves > dorsal roots > DCML/spinothalamic
  • Autonomic
    • Sympathetic
      • Efferent: lateral horn cholinergic preganglionic neurons > ventral roots > white ramus communicans > nAChRs on postganglionic noradrenergic neurons in the paravertebral sympathetic chain or prevertebral ganglia > gray ramus communicans > peripheral nerves > adrenergic receptors (α1/α2, β1/β2) on target organs
      • Afferent: ...
    • Parasympathetic
      • Efferent: cholinergic preganglionic neurons > craniosacral outflow from CN III/VII/IX, CN X, and S2-S4 > nAChRs on postganglionic cholinergic neurons in the parasympathetic/peripheral ganglia on/near target organs > (trigeminal nerve branches for efferents from CN III/VII/IX) > mAChRs on target organs
      • Afferent: ...
  • Enteric