HEC syndrome is an extremely rare birth disorder in which H = communicating Hydrocephalus (excess fluid around the brain), E = Endocardial Fibroelastosis ...

Harlequin syndrome (HS) is a rare problem of the body’s “automatic” (autonomic) nervous system. In HS, the tiny sympathetic nerves that normally make both ...

Hamanishi-Ueba-Tsuji syndrome is an extremely rare hereditary motor-and-sensory neuropathy first described in Japan in 1985. Babies are born with absent or ...

Miller Fisher Syndrome is a rare, nerve-related illness that belongs to the Guillain-Barré Syndrome (GBS) family. While classic GBS mostly weakens the limbs, ...

Acute Motor-Sensory Axonal Neuropathy (often shortened to AMSAN) is one of the rarer, more aggressive “axonal” forms of Guillain-Barré syndrome (GBS). In ...

Acute Motor Axonal Neuropathy—usually shortened to AMAN—is a fast-moving, immune-related attack on the motor (movement-controlling) portions of the peripheral ...

Acute Inflammatory Demyelinating Polyradiculoneuropathy—usually shortened to AIDP—is an autoimmune attack on the insulating myelin sheath that normally helps ...

Guillain–Barré syndrome is an uncommon but serious autoimmune nerve disorder in which the body’s own immune system suddenly turns against the peripheral ...

Gradenigo’s syndrome is the name doctors give to a very specific complication of a middle-ear infection. When bacteria in an episode of acute or chronic otitis ...

Gómez–López-Hernández syndrome (GLHS)—also called cerebello-trigeminal-dermal dysplasia—is an extremely rare neuro-cutaneous disorder first described in 1979. ...

Gillespie syndrome (GS) is an ultra-rare genetic disorder that blends partial or “scalloped” aniridia, congenital or slowly progressive cerebellar ataxia, and ...

Gerstmann–Sträussler–Scheinker syndrome is a very rare, inherited brain disease belonging to the group of human prion disorders. In prion diseases, a perfectly ...

Left-right disorientation (sometimes called left-right confusion or discrimination difficulty) is a neuro-cognitive problem in which a person cannot reliably ...

Finger agnosia is a loss of “finger sense.” A person can feel that a finger is being touched but can’t tell which finger it is, can’t name that finger, and ...

Dysexecutive — sometimes called frontal — acalculia is a loss or severe disturbance of arithmetic ability that springs not from faulty number knowledge itself ...

Spatial acalculia is a specific kind of number-processing problem that appears when the brain’s “map-making” areas are injured or under-developed. People with ...