Typically, episodic ataxia presents as bouts of ataxia induced by startle, stress, or exertion. Some patients also have continuous tremors of various motor groups, known as myokymia. Other patients have nystagmus, vertigo, tinnitus, diplopia or seizures.

Episodic ataxia type-3 (EA3) is similar to EA1 but often also presents with tinnitus and vertigo. Patients typically present with bouts of ataxia lasting less than 30 minutes and occurring once or twice daily. During attacks, they also have vertigo, nausea, vomiting, tinnitus and diplopia. These attacks are sometimes accompanied by headaches and precipitated by stress, fatigue, movement and arousal after sleep. Attacks generally begin in early childhood and last throughout the patients' lifetime. Acetazolamide administration has proved successful in some patients. As EA3 is extremely rare, there is currently no known causative gene. The locus for this disorder has been mapped to the long arm of chromosome 1 (1q42).

AHC patients exhibit a wide range of symptoms in addition to hemiplegic attacks. These can be further characterized as paroxysmal and non-paroxysmal symptoms. Paroxysmal symptoms are generally associated with hemiplegic attacks and may occur suddenly with hemiplegia or on their own. Paroxysmal symptoms may last for variable amounts of time. Non-paroxysmal symptoms tend to be side effects of AHC which are present at all times, not just during episodes or attacks. Epilepsy, which is also considered a paroxysmal symptom, plays an important role in the progression and diagnosis of AHC.

Chronologically, hemiplegic attacks are not always the first symptom of AHC, but they are the most prominent symptom, as well as the symptom for which the disorder is named. Hemiplegic attacks may affect one or both sides of the body, and attacks which affect both sides of the body may be referred to as either or quadriplegic attacks. One of the unique characteristics of AHC is that hemiplegic attacks, as well as other symptoms which may co-occur with hemiplegia, cease immediately upon sleep. During strong attacks, the symptoms may reoccur upon waking. Hemiplegic attacks can occur suddenly or gradually, and the severity of an attack can vary over its duration. The attacks may alternate from one side of the body to another, though this is rare. The length of attacks may also vary from minutes to weeks, though length of attacks varies more greatly between people than between attacks for one person. Both bilateral and hemiplegic attacks are associated with pseudobulbar features such as dysphagia, dysarthria, and respiratory difficulty. Paralysis is also often accompanied by changes in skin color and temperature, sweating, restlessness, tremor, screaming, and the appearance of pain. Hemiplegic attacks happen irregularly and can occur with speech, eating, and swallowing impairment. Patients with AHC are frequently underweight due to these side effects. The average age of onset for hemiplegic episodes has been found to be 6–7 months of age. This early onset gives the name of this disorder the slightly misleading ending 'of childhood'. AHC is not exclusively limited to childhood – attacks become milder after the first ten years of life, but they never completely disappear.

The condition manifests itself as attacks lasting from a few minutes to several hours. Episodes only happen when the individual is awake, and they remain conscious throughout the attack. Symptoms are most severe in youth and lessen with age. Sufferers can have multiple attacks on a daily basis or may have periods of weeks or months between attacks. Symptoms experienced during attacks can vary and include dystonia, chorea, athetosis, ballismus, or a combination.

Onset of symptoms usually occur in early adulthood and is characterized by intention tremor, progressive ataxia, convulsions, and myoclonic epileptic jerks.

Tremors usually affect one extremity, primarily the upper limb, and eventually involve the entire voluntary motor system. Overall, the lower extremity is usually disturbed less often than the upper extremity.

Additional features of the syndrome include: an unsteady gait, seizures, muscular hypotonia, reduced muscular coordination, asthenia, adiadochokinesia and errors with estimating range, direction, and force of voluntary movements. Mental deterioration can occur, however it is rare.

FHM signs overlap significantly with those of migraine with aura. In short, FHM is typified by migraine with aura associated with hemiparesis and, in FHM1, cerebellar degeneration. This cerebellar degeneration can result in episodic or progressive ataxia. FHM can also present with the same signs as benign familial infantile convulsions (BFIC) and alternating hemiplegia of childhood. Other symptoms are altered consciousness (in fact, some cases seem related to head trauma), gaze-evoked nystagmus and coma. Aura symptoms, such as numbness and blurring of vision, typically persist for 30–60 minutes, but can last for weeks and months. An attack resembles a stroke, but unlike a stroke, it resolves in time. These signs typically first manifest themselves in the first or second decade of life.

While not the same in all people, there are several common triggers that can precipitate an attack:

- Moderate to high consumption of stimulants, such as alcohol, caffeine, or nicotine.

- Low amounts of energy due to hunger, lack of sleep, illness, or physical fatigue.

- Moderate to high presence of stress.

- Menstruation and ovulation.

NMT is a diverse disorder. As a result of muscular hyperactivity, patients may present with muscle cramps, stiffness, myotonia-like symptoms (slow relaxation), associated walking difficulties, hyperhidrosis (excessive sweating), myokymia (quivering of a muscle), fasciculations (muscle twitching), fatigue, exercise intolerance, myoclonic jerks and other related symptoms. The symptoms (especially the stiffness and fasciculations) are most prominent in the calves, legs, trunk, and sometimes the face and neck, but can also affect other body parts. NMT symptoms may fluctuate in severity and frequency. Symptoms range from mere inconvenience to debilitating. At least a third of people also experience sensory symptoms.

In one of the few reported cases, the subject presented with muscle weakness and fatigue, muscle twitching, excessive sweating and salivation, small joint pain, itching and weight loss. The subject also developed confusional episodes with spatial and temporal disorientation, visual and auditory hallucinations, complex behavior during sleep and progressive nocturnal insomnia associated with diurnal drowsiness. There was also severe constipation, urinary incontinence, and excessive lacrimation. When left alone, the subject would slowly lapse into a stuporous state with dreamlike episodes characterized by complex and quasi-purposeful gestures and movements (enacted dreams). Marked hyperhidrosis and excessive salivation were evident. Neurological examination disclosed diffuse muscle twitching and spontaneous and reflex myoclonus, slight muscle atrophy in the limbs, absence of tendon reflexes in the lower limbs and diffuse erythema especially on the trunk with scratching lesions of the skin.

Compulsive behaviours, stereotypies and reduplicative paramnesias can be part of the CNS spectrum.

Treatment of Ramsay Hunt Syndrome Type 1 is specific to individual symptoms. Myoclonus and seizures may be treated with drugs like valproate.

Some have described this condition as difficult to characterize.

Familial hemiplegic migraine (FHM) is an autosomal dominant type of hemiplegic migraine that typically includes weakness of half the body which can last for hours, days or weeks. It can be accompanied by other symptoms, such as ataxia, coma and paralysis. There is clinical overlap in some FHM patients with episodic ataxia type 2 and spinocerebellar ataxia type 6, benign familial infantile epilepsy, and alternating hemiplegia of childhood. There are 3 known loci for FHM. FHM1, which accounts for approximately 50% of FHM patients, is caused by mutations in a gene coding for the P/Q-type calcium channel α subunit, CACNA1A. FHM1 is also associated with cerebellar degeneration. FHM2, which accounts for <25% of FHM cases, is caused by mutations in the /-ATPase gene ATP1A2. FHM3 is a rare subtype of FHM and is caused by mutations in a sodium channel α-subunit coding gene, SCN1A. These three subtypes do not account for all cases of FHM, suggesting the existence of at least one other locus (FHM4). Many of the non-familial cases of hemiplegic migraine (sporadic hemiplegic migraine) are also caused by mutations at these loci. A fourth gene that has been associated with this condition is the proline rich transmembrane protein 2 (PRRT2) - an axonal protein associated with the exocytosis complex. A fifth gene associated with this condition is SLC4A4 which encodes the electrogenic NaHCO3cotransporter NBCe1.

There are also non-familial cases of hemiplegic migraine, termed sporadic hemiplegic migraine. These cases seem to have the same causes as the familial cases and represent de novo mutations. Sporadic cases are also clinically identical to familial cases with the exception of a lack of family history of attacks.

Geniospasm is movement disorder of the mentalis muscle.

It is a benign genetic disorder linked to chromosome 9q13-q21 where there are episodic involuntary up and down movements of the chin and lower lip. The movements consist of rapid fluttering or trembling at about 8 Hz superimposed onto a once per three seconds movement of higher amplitude and occur symmetrically in the V shaped muscle. The tongue and buccal floor muscles may also be affected but to a much lesser degree.

The movements are always present but extreme episodes may be precipitated by stress, concentration or emotion and commence in early childhood.

The condition is extremely rare and in a study in 1999 only 23 families in the world were known to be affected, although it may be under-reported. Inheritance is aggressively autosomal dominant. In at least two studies the condition appeared spontaneously in the families.

The condition responds very well to regular botulinus toxin injections into the mentalis muscle which paralyse the muscle but cause no impairment of facial expression or speech.

In all of the reported cases, the need for sleep was severely reduced and in some cases not necessary. The duration of sleep in one case decreased to about 2–4 hours per 24-hour period. Clinical features pertaining to insomnia include daytime drowsiness associated with a loss of ability to sleep, intermingled with confusional oneiric status, and the emergence of atypical REM sleep from wakefulness. The Polysomnogram (PSG) picture of this disease is characterized by an inability to generate physiological sleep (key features are the suppression of the hallmarks of stage 2 non-REM sleep: spindles and K complexes) and by the emergence of REM sleep without atonia. The involvement of the thalamus and connected limbic structures in the pathology indicate the prominent role that the limbic thalamus plays in the pathophysiology of sleep. In a case documented in 1974, PSG findings documented the sustained absence of all sleep rhythms for up to a period of 4 months.

Electroencephalography (EEG) in one case was dominated by "wakefulness" and “subwakefulness” states alternating or intermingled with short (< 1 min) atypical REM sleep phases, characterized by a loss of muscle atonia. The “subwakefulness” state was characterized by 4–6 Hz theta activity intermingled with fast activity and desynchronized lower voltage theta activity, behaviourally associated with sleep-like somatic and autonomic behavior. The subject was said to suffer from “agrypnia excitata”, which consists of severe total insomnia of long duration associated with decreased vigilance, mental confusion, hallucinations, motor agitation, and complex motor behavior mimicking dreams, and autonomic activation. CNS and autonomic symptoms were caused by impaired corticolimbic control of the subcortical structures regulating the sleep-wake and autonomic functions.

SCA13 is typified by early onset, mildly progressive cerebellar ataxia with accompanying dysarthria, mental retardation, and nystagmus. Symptoms and age of onset can vary slightly according to the causative mutation.

There are three main types of NMT:

- Chronic

- Monophasic (symptoms that resolve within several years of onset; postinfection, postallergic)

- Relapsing Remitting

Unlike ataxias of cerebellar origin, Bruns apraxia exhibits many frontal lobe ataxia characteristics, with some or all present.

- Difficulty in initiating movement

- Poor truncal mobility

- Falls due to minor balance disturbances

- Greatly hindered postural responses

- Characteristic magnetic gait, the inability to raise one's foot off of the floor.

- Wide base, poor balance control when in stance

- Short stride

- En bloc turns

Often patients with frontal lobe ataxia may experience minute cognitive changes that accompany the gait disturbances, such as frontal dementia and presentation of frontal release signs (Plantar reflex). Urinary incontinence may also be present.

Bruns apraxia can be distinguished from Parkinsonian ataxia and cerebellar ataxia in a number of ways. Patients typically afflicted with Parkinsonian ataxia typically have irregular arm swing, a symptom not typically present in frontal ataxia. Walking stride in cerebellar ataxia varies dramatically, accompanied by erratic foot placement and sudden, uncontrolled lurching, not generally characteristic of Bruns apraxia.

Spinocerebellar ataxia type 13 (SCA13) is a rare autosomal dominant disorder, which, like other types of SCA, is characterized by dysarthria, nystagmus, and ataxia of gait, stance and the limbs due to cerebellar dysfunction. Patients with SCA13 also tend to present with epilepsy, an inability to run, and increased reflexes. This cerebellar dysfunction is permanent and progressive. SCA13 is caused by mutations in KCNC3, a gene encoding a voltage-gated potassium channel K3.3. There are two known mutations in this gene causative for SCA13. Unlike many other types of SCA, these are not polyglutamine expansions but, rather, point mutations resulting in channels with no current or altered kinetics.

Autosomal recessive cerebellar ataxia type 1 (ARCA1) is a condition characterized by progressive problems with movement. Signs and symptoms of the disorder first appear in early to mid-adulthood. People with this condition initially experience impaired speech (dysarthria), problems with coordination and balance (ataxia), or both. They may also have difficulty with movements that involve judging distance or scale (dysmetria). Other features of ARCA1 include abnormal eye movements (nystagmus) and problems following the movements of objects with their eyes. The movement problems are slowly progressive, often resulting in the need for a cane, walker, or wheelchair.

Most cases of autosomal recessive cerebellar ataxia are early onset, usually around the age of 20. People with this type of ataxia share many characteristic symptoms including:

- frequent falls due to poor balance

- imprecise hand coordination

- postural or kinetic tremor of extremities or trunk

- dysarthria

- dysphasia

- vertigo

- diplopia

- lower extremity tendon reflexes

- dysmetria

- minor abnormalities in ocular saccades

- attention defects

- impaired verbal working memory and visuospatial skills

- Normal life expectancy

Autosomal recessive ataxias are generally associated with a loss of proprioception and vibration sense. Arreflexia is more common in autosomal recessive ataxia than autosomal dominant ataxias. Also, they tend to have more involvement outside of the nervous system. Mutations in subunit of the mitochondrial DNA polymerase (POLG) have been found to be a potential cause of autosomal recessive cerebellar ataxia.

The ICHD classification and diagnosis of migraine distinguish 6 subtypes of hemiplegic migraine. FHM can be loosely divided into two categories: with and without cerebellar signs. Cerebellar signs refer to ataxia, sometimes episodic and other times progressive, that can accompany FHM1 mutations and is caused by degeneration of the cerebellum. These cerebellar signs result in a phenotypic overlap between FHM and both episodic ataxia and spinocerebellar ataxia. This is unsurprising as subtypes of these disorders (FHM1, EA2 and SCA6) are allelic, i.e., they result from mutations in the same gene. The other forms of FHM seem to be distinguishable only on the basis of their genetic cause.

Deep brain stimulation may provide relief from some symptoms of Benedikt syndrome, particularly the tremors associated with the disorder.

SCA6 is typified by progressive and permanent cerebellar dysfunction. These cerebellar signs include ataxia and dysarthria, likely caused by cerebellar atrophy. Prior to diagnosis and the onset of major symptoms, patients often report a feeling of "wooziness" and momentary imbalance when turning corners or making rapid movements. The age at which symptoms first occur varies widely, from age 19 to 71, but is typically between 43 and 52. Other major signs of SCA6 are the loss of vibratory and proprioceptive sensation and nystagmus.

While most patients present with these severe progressive symptoms, others, sometimes within the same family, display episodic non-progressive symptoms more similar to episodic ataxia. Still others present with symptoms common to both SCA6 and familial hemiplegic migraine.

Bhaskar–Jagannathan has symptoms such as long fingers, thin fingers, poor balance, incoordination, high levels of amino acids in urine, cataracts during infancy, and ataxia. Ataxia, which is a neurological sign and symptom made up of gross incoordination of muscle movements and is a specific clinical manifestation

Bruns apraxia, or frontal ataxia is a gait apraxia found in patients with bilateral frontal lobe disorders. It is characterised by an inability to initiate the process of walking, despite the power and coordination of the legs being normal when tested in the seated or lying position. The gait is broad-based with short steps with a tendency to fall backwards. It was originally described in patients with frontal lobe tumours, but is now more commonly seen in patients with cerebrovascular disease.

It is named after Ludwig Bruns.