This chapter provides the clarification of acronyms, brief definitions of signs, and short descriptions of syndromes. Detailed elaboration of some of these will be found in the text. Short outlines of rare syndromes will be added as full discussions cannot be included in an introductory text. By necessity this will only be a selection from the myriad numbers of syndromes and signs to choose from.
KeywordsTerminology Acronyms Definitions Signs Syndromes
Anterior cerebral artery
Anterior communicating artery
Acute demyelinating encephalomyelitis
Anterior inferior cerebellar artery
Anterior inflammatory demyelinating polyneuropathy
Acquired immune deficiency syndrome
Anterior ischemic optic neuropathy
Amyotrophic lateral sclerosis
Altered mental status
Afferent pupillary defect
Benign paroxysmal positional vertigo
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy
Calcitonin gene-related peptide
Chronic inflammatory demyelinating polyneuropathy
Central nervous system
Chronic progressive external ophthalmoplegia
Cycles per second
Central sleep apnea
Cortical spreading depression
Carpal tunnel syndrome
Glutamic acid decarboxylase
Human immunodeficiency virus
Inferior oblique muscle
Inferior rectus muscle
Juvenile myoclonic epilepsy
Levator palpebrae superioris
Lateral rectus muscle
Middle cerebral artery
Mitochondrial encephalopathy with lactic acidosis and stroke
Medial longitudinal fasciculus
Medial rectus muscle
Multiple system atrophy
Multiple sleep latency test
Neuromyelitis optica (Devic’s disease)
Normal pressure hydrocephalus
Obsessive compulsive disorder
Obstructive sleep apnea
Posterior cerebral artery
Polymerase chain reaction
Posterior inferior cerebellar artery
Posterior ischemic optic neuropathy
Periodic limb movements of sleep
Progressive multifocal leukoencephalopathy
Peripheral nervous system
Paramedian pontine reticular formation
Posterior reversible encephalopathy syndrome
Progressive supranuclear palsy
REM behavior disorder of sleep
Rapid eye movement
Rostral interstitial nucleus of the MLF
Reflex sympathetic dystrophy
Superior cerebellar artery
Superior rectus muscle
Selective norepinephrine reuptake inhibitor
Selective serotonin reuptake inhibitor
Short-lasting unilateral neuralgiform headaches with conjunctival injection and tearing
Ventral posterolateral nucleus of thalamus
Ventral posteromedial nucleus of thalamus
Wall-eyed bilateral internuclear ophthalmoplegia
Wall-eyed monocular internuclear ophthalmoplegia
After a nerve is injured there is regrowth of axons but some are redirected to the wrong muscle. This commonly results in a synkinesia. A good example is after recovery from a Bell’s palsy when an eye blink provokes movement of the mouth (orbicularis oris).
Patients with abulia are passive, apathetic, and have little interest in their surroundings.
This is a large, usually unilateral pupil which is nonreactive to light and has slow constriction to a prolonged near stimulus.
Examination method for detecting a thoracic outlet syndrome (see Chap. 4).
There is a normal consensual response to light but dilation when the light is rapidly switched back from the normal to the involved eye. The involved pupil may react normally or sluggishly to a direct light stimulus. This response indicates optic nerve pathology.
Normal reception of a specific sensory stimulus with the inability to recognize the object using the same sensory system, but there is retained ability to recognize it using a different sensory pathway.
Inability to write.
A voluntary movement to relieve an inner restlessness typically manifested by walking or rocking. Ordinarily this is due to use of dopamine receptor blockers.
Patients in an akinetic mute state are immobile, do not speak but appear vigilant as the eyes are open, and there are occasional pursuit and saccadic eye movements.
Nystagmus is more rapid when the eyes are deviated in the direction of the quick phase.
Inability to read.
Patients are unable to read what they have just written due to a lesion of the dominant occipital lobe and splenium of the corpus callosum.
Unilateral wandering involuntary hand movements, a sign often observed with corticobasal ganglia degeneration, but not pathognomonic of this disorder.
Sensation of a stimulus on one side is perceived as arising from the contralateral side in the same location.
A nonpainful stimulus perceived as painful.
Pain in a region of hypesthesia, typical of postherpetic neuralgia.
Lack of concern about a neurologic deficit, typically a hemiparesis.
Absolute denial of a neurologic deficit, typically a hemiparesis.
Impaired language function (see Chap. 4).
The patient is mute but is able to write. Lesions are usually in Broca’s area or in adjacent subcortical white matter.
This refers to a breathing pattern of 2–3 s of apnea after a deep inspiration.
Impaired performance of a learned movement despite preserved strength.
Small irregular pupils, poorly or nonreactive to light with a normal reaction to a near stimulus.
Loss of awareness of one-half of the body.
A lurching gait with irregular steps associated with a conversion reaction.
The flapping downward tremor typically seen in the hands when the arms are extended in the pronated position with the wrists dorsiflexed. This is considered a negative myoclonus and is associated with any type of metabolic encephalopathy.
Slow, writhing, involuntary, large amplitude movements involving distal upper extremities, and less often face and trunk musculature.
Failure of a patient to recognize or name his own limb or body part.
Abrupt swinging movements of an arm or leg involving proximal muscles due to a lesion in the contralateral subthalamic nucleus.
Movement of the umbilicus upward with head flexion when there is paresis of lower abdominal muscles due to a spinal cord lesion at T10.
A normal eye movement up and out with eye closure.
Increased diplopia due to a 4th nerve lesion when the head is tilted toward the side of the lesion.
A nonfluent aphasia with good comprehension and poor repetition (see Chap. 4).
A condition in which the thoraco-lumbar spine is flexed when walking but not in bed. This sign is common in Parkinson’s disease, Parkinson-plus syndromes, and dystonia.
A sudden decrease in muscular tone most often in the legs occasionally resulting in falls. This is a cardinal feature of narcolepsy.
See complex regional pain syndrome.
An extensor plantar response when the lateral side of the foot is scraped beginning at the heel and extending up to the base of the fifth toe.
This refers to abnormal respiration manifested by short periods of hyperpnea alternating with apnea in a crescendo-decrescendo pattern.
Rapid jerky movements of the extremities, most prominent in distal musculature.
When patients with ocular myasthenia gravis look from a down to a neutral position, the upper eyelid may twitch upward transiently uncovering the sclera.
Eyelid retraction associated with the pretectal syndrome (Parinaud’s, Sylvian aqueduct, dorsal midbrain syndromes).
A fluent aphasia with good comprehension and poor repetition.
Use of obscene language.
Use of obscene gestures.
Paresis of one arm and the contralateral leg.
This refers to a hemiparesis, leg greater than arm.
The signs of increased intracranial pressure, hypertension, bradycardia, and slow respiratory rate.
A sense of reliving an experience.
A false belief.
A sense of detachment from the body.
A feeling of being disconnected from the environment.
A specific test for benign paroxysmal positional vertigo (see Chap. 4).
Monocular elevation paresis due to a contralateral supranuclear pretectal lesion or an ipsilateral lesion of efferent fibers from the riMLF to SR and IO subnuclei.
Impairment of rapid alternating movements, a nonlocalizing neurologic sign.
Unpleasant sensations provoked by an ordinary stimulus.
Abnormal involuntary repetitive movements.
This term is usually applied to loss of inflection in speech producing a monotone quality. It also refers to changes in the emphasis or timing of words and pauses between words in a phrase.
Slow involuntary movements or sustained postures usually involving truncal and proximal-greater-than-distal movements of the extremities.
The repetition of words or phrases just spoken to the patient.
This term refers to an upper brachial plexus lesion affecting C5–C6 roots. The name is usually applied to a birth injury but may be used with any traumatic lesion or idiopathic plexitis.
This term refers to a lesion adjacent to brain.
An uncontrollable acceleration of gait most often observed in patients with Parkinson’s disease.
See paratonic rigidity.
The term used to describe sudden, uncontrollable laughter associated with a seizure disorder.
An abnormal response to repetitive tapping over the bridge of the nose manifested by continuous involuntary blinking.
(See Chap. 5).
Lid lag on looking down due to thyroid disease.
A sensory experience without an external stimulus.
Flexion of the distal phalanx of the thumb when the middle finger is hyperextended and the nail is flicked downward.
A finding associated with feigned weakness of a leg as the patient does not apply the downward pressure on the contralateral leg when requested to raise the weak leg.
A scale to assess severity of subarachnoid hemorrhage (see Chap. 7).
This is a widely dilated, poorly or nonreactive pupil which is an early sign of uncal herniation due to compression of the peripherally located pupillary fibers of the third nerve.
Exaggerated response to a painful stimulus.
Acute sensitivity to a sensory stimulus.
Decreased perception of a stimulus.
This refers to a patient with little spontaneous expression, masked facies.
Distortion of a sensory perception.
Night terrors in adults manifested by screaming during stage 3 sleep.
Ipsilateral medial rectus paresis with or without nystagmus in the contralateral abducting eye, with or without preservation of convergence. The lesion is in the medial longitudinal fasciculus.
Abduction paresis attributed to impaired inhibition of the ipsilateral medial rectus secondary to a lesion of the midbrain or rostral pons.
This term refers to a lesion within brain.
A feeling that one’s surroundings are unfamiliar.
Compression of the opposite cerebral peduncle against the incisura of the tentorium cerebelli during uncal herniation. This causes a hemiparesis ipsilateral to the involved cerebral hemisphere.
Lower brachial plexopathy involving C8–T1 roots usually due to trauma or infrequently an invasive neoplasm.
Demeanor inconsistent with the presumed illness.
The straight leg raising test used to examine for lumbar radiculopathy.
Electricity-like sensations which radiate down the arms, occasionally the back and legs, provoked by head flexion. This may be due to increased sensitivity of the posterior columns and is a sign most often associated with multiple sclerosis but may occur with other pathologies such as cervical spinal stenosis.
Claw hand deformity due to an ulnar nerve lesion above the elbow. There is hyperextension of the 4th, 5th and occasionally third fingers at the metacarpal phalangeal joints and flexion at the interphalangeal joints.
Patients have difficulty initiating steps and their feet appear stuck to the floor. If able to walk the gait is shuffling and turning requires several steps.
See magnetic gait.
Unilateral lid retraction with jaw movement or swallowing.
See afferent pupillary defect.
Compression of the lateral femoral cutaneous nerve of the thigh (L2–L3) under the inguinal ligament causing numbness, pain, and paresthesias in the nerve’s distribution over the anterolateral thigh.
A distortion of form such as a straight line becoming crooked.
See glabellar reflex.
A brief shock-like movement due to either muscle contraction (positive) or muscle inhibition (negative).
Continuous slow muscle twitching producing an undulation of the muscle surface.
Impaired muscle relaxation after it is tapped, usually at the thenar eminence.
This term refers to a patient who pays no attention to a weak limb but, when specifically requested, can use it. This sign is usually associated with contralateral parietal lobe lesions.
A paraphasia manifested by a new word manufactured by the patient.
Burning, itching, and paresthesias at the medial margin of the scapula in a well-circumscribed region a few inches in diameter. The etiology is unknown.
See Dix–Hallpike test.
Absence of volitional saccades and pursuit.
Loss of automatic breathing during sleep. This can be caused by lesions of the tegmentum of the medulla or high cervical cord at C1–C2.
This term refers to the type of facial sensory loss with intramedullary lesions involving the trigeminal sensory system.
An extensor plantar sign evoked by firmly scraping down the shin from the knee to the foot using the knuckles.
Inability to reach a target which is clearly seen.
An illusory perception of movement of the environment.
Drop attack associated with Ménière’s disease and described by patients as a sensation of being pushed or thrown to the ground.
Compulsive repetition of phrases or words at increasing speed and diminishing volume.
The patient perceives an auditory stimulus after the auditory stimulus has been removed.
The perseveration of a visual image which is no longer present.
This term refers to abnormal formation of words, inappropriate use of words, or manufactured new words. This is a diagnostic feature of aphasia.
The patient with paratonia actively resists a passive motion at a joint despite an admonition to relax. This is also known by the term Gegenhalten.
Night terrors in children manifested by screaming during stage 3 sleep.
A sense that objects are looming up in front of the patient. This may be a simple partial seizure.
Repetition of the same response to a new question.
Flexion of the wrist to 90° for up to 60 s may produce paresthesias in the hand due to irritation of the median nerve.
Flashes of light which may occur with pressure on the globe, rapid saccades, traction on the vitreous, and accommodation. They can be an early sign of retinal detachment.
A selective inability to recognize faces.
This usually refers to involuntary laughing or crying associated with bilateral lesions of corticobulbar pathways. Impairment of speech, swallowing, chewing, and breathing may also be present.
A type of aberrant third nerve regeneration with elevation of the lid on downgaze.
Purposeless motor activity such as fiddling with the bed sheets.
See complex regional pain syndrome.
Visual perception of movement in a hemianopic field.
Unsteadiness when standing with eyes closed and feet together.
Ability to see individual elements of a picture or scene but inability to comprehend or synthesize its meaning or how to interrelate the parts.
Vertical separation of the globes.
Grading of an arteriovenous malformation by its size, location, and venous drainage (see Chap. 7).
Infrequent blinking in Grave’s disease.
An involuntary movement of a muscle which should not ordinarily contract when a voluntary movement is initiated elsewhere.
A term applied to delayed development of dyskinesias or dystonia after initiating treatment with a dopamine-blocking agent.
“Walled vision” as occurs in a homonymous hemianopsia.
Objects appear at a distance. Brief episodes of teleopsia may indicate simple partial seizures.
Brief sudden movements or sounds which are often repetitive and stereotyped.
Tingling provoked by percussion over an injured nerve.
This is a focal neurologic deficit present after a seizure.
Cervical dystonia manifested by spasm of neck musculature with the head drawn to one side and the chin pointing to the other side.
This term usually refers to nystagmus which has a predominant rotatory component.
This phenomenon occurs when a sound at a specific frequency produces paroxysmal vertigo and nystagmus.
See otolithic crisis.
Exacerbation or provocation of a neurologic deficit due to exercise or elevation of body temperature.
Condition in which the patient is awake but unaware (see Chap. 5).
Vertigo, vomiting, and diaphoresis.
A fluent aphasia with poor comprehension and poor repetition.
Inappropriate affect manifested by joking which may be present in patients with frontal lobe lesions.
Yellow color of centrifuged CSF supernatant after CNS hemorrhage. The yellow color is due to bilirubin.
The anterior interosseous nerve is a purely motor branch of the median nerve. An injury causes pain in the proximal forearm, paresis of pronation, paresis of flexion of the terminal phalanges of the thumb, second and third fingers, and inability to pinch.
(See Chap. 11, Case 27).
Denial of blindness which is usually a sign of bilateral occipital lobe infarctions.
Simultanagnosia, optic ataxia and oculomotor apraxia.
This autosomal recessive disorder is associated with an external ophthalmoplegia and clinical signs indicating posterior column, spinocerebellar, and corticospinal tract involvement. Laboratory abnormalities include abetalipoproteinemia, acanthocytosis, and hypocholesterolemia.
Third nerve palsy and contralateral ataxia, chorea or tremor due to involvement of third nerve fibers and the red nucleus.
Hemisection or damage to one-half of the spinal cord which results in an ipsilateral spastic paresis, ipsilateral loss of vibration and position sense below the level of the lesion, and contralateral pain and temperature loss one or two levels below the lesion.
Mechanical restriction of the superior oblique tendon at the pulley suggesting an inferior oblique paresis.
Paresthesias and/or weakness in the distribution of the median nerve due to its compression between the carpal bones and the transverse carpal ligament.
Lesion of lower lumbar (L4–L5) and sacral roots (S1–S5) which may cause a paraparesis, sphincter disturbances, and severe pain with sensory loss in the buttocks, perianal, genital, and perineal regions.
Lesions within the cavernous sinus which variably affect the 3rd, 4th, and 6th nerves, the first two divisions of the 5th cranial nerve and sympathetic fibers within the carotid sheath.
Lesions in this angle affect primarily the 5th, 7th, and 8th cranial nerves and adjacent cerebellum. Schwannomas of the 8th cranial nerve are the most common etiology.
This syndrome is characterized by vivid, visual, and nonthreatening hallucinations of people or objects in patients with severe visual loss, most often due to severe retinal disease. The patient is aware that they are unreal.
Oculosympathetic irritation causing periodic pupillary dilatation, lid retraction, facial hyperhidrosis, and headache.
Tissue swelling, muscular atrophy, and bony changes associated with severe pain secondary to trauma which is often minor.
An ulnar neuropathy due to the nerve being compressed at the elbow by a fibrous band, bone fragment, or bulging of the medial collateral ligament.
This disorder includes a cystic 4th ventricle, partial or complete absence of the cerebellum and an enlarged posterior fossa.
See pretectal syndrome.
Thoracic outlet syndrome primarily in women secondary to intermittent compression of the brachial plexus caused by drooping shoulders associated with a long swan neck and downward slope of the clavicles.
Type I is paresis of abduction of one eye associated with narrowing of the palpebral fissure with or without retraction of the globe on attempted adduction. Type II is impaired adduction. Type III is impaired abduction and adduction. The lesion is probably of congenital origin. The retraction syndrome may be due to anomalous innervation of the lateral rectus muscle by the inferior division of the oculomotor nerve.
Ipsilateral anosmia, optic atrophy, and contralateral papilledema. This is usually due to an olfactory groove meningioma. A pseudo-Foster Kennedy syndrome may be due to sequential AION.
Ipsilateral gaze deviation and contralateral hemiparesis.
A pontine lesion which causes an ipsilateral 7th nerve paresis with ipsilateral gaze paresis and contralateral hemiparesis. The eyes look at the hemiparesis.
Acalculia, finger agnosia, agraphia, and right–left confusion due to a lesion of the dominant angular gyrus.
See Tourette’s syndrome.
A lesion which affects the ophthalmic division of the trigeminal nerve and the 6th cranial nerve associated with either an infection (petrositis) or neoplasm of the apex of the temporal bone.
Acute inflammatory demyelinating polyneuropathy (see Chap. 9, Case 8).
Ptosis, miosis, and anhidrosis (see Chap. 8).
The prominent feature of neuromyotonia is continuous myokymia especially of distal musculature which persists in sleep. Symptoms include muscle stiffness, cramps, and occasionally hyperhidrosis.
Ninth, 10th, and 11th cranial nerve pathology usually due to a tumor at the foramen.
Chronic progressive external ophthalmoplegia (CPEO) beginning in childhood associated with heart block, retinal pigment degeneration, short stature, abnormal muscle mitochondria, spongiform encephalopathy, and occasionally cerebellar ataxia.
Episodes of hypersomnia, hyperphagia, and hypersexual behavior.
The lack of capacity for anger or fear, hyperorality, and hypersexuality secondary to bilateral lesions in the frontotemporal parts of the limbic system (amygdala, piriform cortex and adjacent hippocampus).
Loss of short-term memory plus confabulation. Although it is a well-known complication of chronic alcoholism, it is not a pathognomonic sign and is not infrequent in patients with Alzheimer’s disease.
Characteristic syndromes associated with small ischemic infarctions in subcortical or brainstem locations. These lacunar infarctions are due to small vessel penetrating artery disease (see Chap. 7).
See Wallenberg’s syndrome.
Disorder of the neuromuscular junction due to decreased release of packets of acetylcholine from the presynaptic terminal caused by an abnormal voltage-dependent calcium channel.
Action myoclonus caused by an hypoxic brain injury.
Acquired epileptic aphasia in children.
Childhood onset of multiple seizure types associated with mental retardation which is cryptogenic or symptomatic and often refractory to treatment.
Quadriplegia, horizontal gaze palsy, preservation of vertical eye movements with normal alertness, and cognition (see Chap. 5).
See internuclear ophthalmoplegia of abduction.
Bilateral arm paresis with good preservation of leg function.
Ipsilateral cerebellar ataxia, contralateral hemiparesis, and variable contralateral hemihypesthesia. This is due to a lateral pontine lesion involving the middle cerebellar peduncle and adjacent corticospinal tract.
Oral mandibular dystonia and blepharospasm.
Recurrent unilateral or bilateral facial palsies with fissured (scrotal) tongue and facial swelling.
Congenital lesion of the 6th nucleus causing an abduction paresis. Facial diplegia and occasionally other cranial nerves may be affected.
These patients simulate illness to obtain medical treatment without an obvious motive.
Hyperthermia, extrapyramidal signs, altered mental status, and elevated CPK due to an idiosyncratic reaction to neuroleptics or an abrupt withdrawal from levodopa treatment.
See Isaac’s syndrome.
This is a neuropathy of the mental nerve causing numbness of the chin, occasionally lower lip, and mucus membrane of the inside of the lower lip. It can be a sign of metastatic neoplasm.
This occurs from a unilateral PPRF and adjacent MLF lesion. It causes an ipsilateral gaze palsy and ipsilateral adduction paresis with consequent retention of only abduction of the contralateral eye. Vertical eye movements are usually preserved.
See pretectal syndrome.
This is a painful brachial plexitis usually of viral or immune origin.
Polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes.
Recurrent weakness, atrophy, fatigue, and pain occurring 15 years or more after acute poliomyelitis.
Tachycardia, 30 beats higher than the resting rate, with minimal exertion, and associated with chronic fatigue.
This includes paresis of upward gaze and, variably, convergence-retractory nystagmus, lid retraction, lid lag, and large round pupils poorly or nonreactive to light. Light-near dissociation may be present.
Sciatic nerve entrapment as it passes through the greater sciatic notch.
Persistent, unilateral orbital, and eye pain associated with miosis and ptosis.
Herpes zoster affecting the geniculate ganglion causing a facial palsy of Bell’s type often with a vesicular eruption on the eardrum and external auditory meatus.
See complex regional pain syndrome.
This is an X-linked disorder in girls who develop stereotypical behaviors, cognitive impairment, and extrapyramidal manifestations. It is considered an autism spectrum disorder.
An acute encephalopathy with altered mental status and liver dysfunction manifested by elevated liver enzymes and/or hyperammonemia probably secondary to a virus (influenza A, B and varicella virus) with a concomitant exposure to an exogenous substance, especially aspirin.
An autosomal recessive myotonic disorder in children manifested by continuous motor activity in muscles, especially in the face and thighs, blepharospasm, and constant motor activity of chin and lips.
Hyperthermia, myoclonus, extrapyramidal signs, and altered mental status secondary to SSRIs.
Parkinsonism plus autonomic dysfunction. This is now encompassed by the term multiple system atrophy (MSA).
Progressive supranuclear palsy. This combines parkinsonism, vertical gaze paresis (primarily downgaze), dementia, and nuchal rigidity.
This motor system disease, occasionally paraneoplastic, is manifested by painful fluctuating rigidity and spasms of axial and limb musculature commonly exacerbated by external stimuli. There are usually markedly increased antibodies to glutamic acid decarboxylase (GAD), an enzyme which breaks down glutamic acid to GABA, an inhibitory neurotransmitter.
Findings are similar to the cavernous sinus syndrome since the third, fourth, ophthalmic division of 5th and 6th cranial nerves pass through this fissure. Pain, paresthesias and sensory loss in the ophthalmic division of the 5th nerve, Horner’s syndrome, and exophthalmos may be present.
See pretectal syndrome.
Entrapment of the posterior tibial nerve at the ankle.
Vitreous hemorrhage associated with intracranial hemorrhage.
Severely disagreeable or painful cutaneous symptoms contralateral to a thalamic lesion.
Symptoms and signs due to compression of the brachial plexus and arteries in that region. The C8 and T1 roots are especially susceptible to damage from fibrous bands over a cervical rib.
Granulomatous inflammation in the cavernous sinus causing a painful ophthalmoplegia with variable involvement of the 3rd, 4th, first division of the 5th and 6th cranial nerves. There is occasional optic nerve involvement and Horner’s syndrome.
Vascular occlusive disease of the rostral portion of the basilar artery, commonly cardioembolic, resulting in midbrain, thalamic, temporal lobe and occipital lobe infarctions, often bilateral.
See jugular foramen syndrome.
Vertical upgaze palsy and monocular paresis of downgaze associated with thalamo-mesencephalic infarctions.
Unilateral infarction of the dorsolateral medulla due to ischemia in the distribution of the posterior inferior cerebellar artery. Characteristic findings are horizontal gaze-evoked nystagmus, ipsilateral Horner’s syndrome, ipsilateral facial hypesthesia, contralateral hemihypesthesia, ipsilateral palate and vocal cord paresis, ipsilateral cerebellar ataxia, and occasional singultus (hiccups).
Injury to the superficial cutaneous branch of the radial nerve resulting in numbness and paresthesias of the dorsal aspect of the first three fingers and dorsum of the hand, radial portion. This is also known as cheiralgia paresthetica.
Third nerve palsy and contralateral hemiparesis including the lower face.
Altered sensorium, ataxia, and oculomotor abnormalities due to thiamin deficiency, usually a complication of alcoholism.
Seizures in infancy manifested by flexor or extensor spasms, mental retardation, and a typical EEG pattern called hypsarrhythmia.