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Brain dump — use this page to memorize organ → sympathetics → parasympathetics → classic exam association.

Viscerosomatic/Autonomic Grid

Organ/SystemSympatheticsParasympatheticsKey reflex / exam association
Head / Eyes / ENTT1–T4CN III, VII, IX, XUpper thoracic dysfunction can show up with head/neck symptoms; CN parasympathetics handle lacrimation, salivation, pupillary constriction
HeartT1–T5CN XCardiac viscerosomatics: T1–T5, often left-sided upper thoracic/rib dysfunction
Lungs / BronchiT2–T7CN XPulmonary reflexes: upper-mid thoracics; rib mechanics matter
EsophagusT2–T8CN XGERD/esophageal pathology can refer to upper-mid thoracics
StomachT5–T9CN XForegut; classic upper/mid thoracic association
Liver / GallbladderT5–T9CN XChapman: gallbladder often associated with right-sided findings
Pancreas / SpleenT5–T9CN XForegut-level sympathetic range
Small intestineT9–T11CN XMidgut; vagus parasympathetics until proximal 2/3 transverse colon
AppendixT10CN XClassic: T10 = umbilical referral
Cecum / Ascending colonT10–T12CN XMidgut colon
Proximal 2/3 transverse colonT10–T12CN XLast major vagal GI territory
Distal 1/3 transverse colonL1–L2S2–S4Hindgut transition: parasympathetics switch to pelvic splanchnics
Descending / Sigmoid colonL1–L2S2–S4Hindgut
RectumL1–L2S2–S4Pelvic splanchnics: S2–S4 keeps the poop off the floor
Kidneys / UretersT10–L2CN X / S2–S4Renal/ureter pain can track flank → groin; sympathetics T10–L2
Adrenal glandsT10–L1Sympathetic-heavy organ; adrenal medulla receives preganglionic sympathetics
BladderT11–L2S2–S4Sympathetics store urine; parasympathetics void
Prostate / GU pelvic organsT10–L2S2–S4Pelvic organs commonly test sacral parasympathetics
Uterus / CervixT10–L2S2–S4Labor/cervix pain often pelvic/sacral association
Ovaries / TestesT10–T11Gonads originate high embryologically → T10-ish referral

Must know — these are the fastest autonomic points to recall under pressure.

High-yield autonomic rules

FunctionSympatheticParasympathetic
Heart rateIncreases HR/contractilityDecreases HR
BronchiBronchodilationBronchoconstriction + secretions
GI motilityDecreases motilityIncreases motility
GI sphinctersContracts sphinctersRelaxes sphincters
BladderRelaxes detrusor, contracts internal sphincter = storageContracts detrusor, relaxes sphincter = voiding
PupilDilates pupilConstricts pupil
Sweat glandsIncreases sweatingNo major effect
Blood vesselsVasoconstriction mostlyMinimal direct effect

Ultra-compact brain dump version

HEAD/NECK:      T1–T4     CN III, VII, IX, X
HEART:          T1–T5     X
LUNGS:          T2–T7     X
FOREGUT:        T5–T9     X
MIDGUT:         T9–T12    X
HINDGUT:        L1–L2     S2–S4
KIDNEY/URETER:  T10–L2    X/S2–S4
BLADDER:        T11–L2    S2–S4
GONADS:         T10–T11
PELVIC ORGANS:  T10–L2    S2–S4

Memory hooks

  • 🧠 Autonomics — Vagus goes to the splenic flexure: foregut + midgut through proximal 2/3 transverse colon.
  • 🧠 Autonomics — Pelvic splanchnics S2–S4: hindgut + pelvic organs.
  • 🫀 Heart — T1–T5.
  • 🫁 Lungs — T2–T7.
  • 🍽️ Foregut — T5–T9.
  • 🚨 Trap — T10 = appendix/umbilicus.
  • 🚻 GU/pelvis — T10–L2 = urinary + gonadal/pelvic sympathetics.