Arts syndrome should be included in the differential diagnosis of infantile hypotonia and weakness aggravated by recurrent infection with a family history of X-linked inheritance. Sequence analysis of PRPS1, the only gene associated with Arts syndrome, has detected mutations in both kindreds reported to date. Arts syndrome patients were also found to have reduced levels of hypoxanthine levels in urine and uric acid levels in the serum. In vitro, PRS-1 activity was reduced in erythrocytes and fibroblasts.

Currently, purine replacement via S-adenosylmethionine (SAM) supplementation in people with Arts syndrome appears to improve their condition. This suggests that SAM supplementation can alleviate symptoms of PRPS1 deficient patients by replacing purine nucleotides and open new avenues of therapeutic intervention. Other non-clinical treatment options include educational programs tailored to their individual needs. Sensorineural hearing loss has been treated with cochlear implantation with good results. Ataxia and visual impairment from optic atrophy are treated in a routine manner. Routine immunizations against common childhood infections and annual influenza immunization can also help prevent any secondary infections from occurring.

Regular neuropsychological, audiologic, and ophthalmologic examinations are also recommended.

Carrier testing for at-risk relatives and prenatal testing for pregnancies at increased risk are possible if the disease-causing mutation in the family is known.

Ultrasonography of the scrotum is useful when there is a suspicion of some particular diseases. It may detect signs of testicular dysgenesis, which is often related to an impaired spermatogenesis and to a higher risk of testicular cancer. Scrotum ultrasonography may also detect testicular lesions suggestive of malignancy. A decreased testicular vascularization is characteristic of testicular torsion, whereas hyperemia is often observed in epididymo-orchitis or in some malignant conditions such as lymphoma and leukemia. Doppler ultrasonography useful in assessing venous reflux in case of a varicocele, when palpation is unreliable or in detecting recurrence or persistence after surgery, although the impact of its detection and surgical correction on sperm parameters and overall fertility is debated.

Dilation of the head or tail of the epididymis is suggestive of obstruction or inflammation of the male reproductive tract. Such abnormalities are associated with abnormalities in sperm parameters, as are abnormalities in the texture of the epididymis. Scrotal and transrectal ultrasonography (TRUS) are useful in detecting uni- or bilateral congenital absence of the vas deferens (CBAVD), which may be associated with abnormalities or agenesis of the epididymis, seminal vesicles or kidneys, and indicate the need for testicular sperm extraction. TRUS plays a key role in assessing azoospermia caused by obstruction, and detecting distal CBAVD or anomalies related to obstruction of the ejaculatory duct, such as abnormalities within the duct itself, a median cyst of the prostate (indicating a need for cyst aspiration), or an impairment of the seminal vesicles to become enlarged or emptied.

Some strategies suggested or proposed for avoiding male infertility include the following:

- Avoiding smoking as it damages sperm DNA

- Avoiding heavy marijuana and alcohol use.

- Avoiding excessive heat to the testes.

- Maintaining optimal frequency of coital activity: sperm counts can be depressed by daily coital activity and sperm motility may be depressed by coital activity that takes place too infrequently (abstinence 10–14 days or more).

- Wearing a protective cup and jockstrap to protect the testicles, in any sport such as baseball, football, cricket, lacrosse, hockey, softball, paintball, rodeo, motorcross, wrestling, soccer, karate or other martial arts or any sport where a ball, foot, arm, knee or bat can come into contact with the groin.

- Diet: Healthy diets (i.e. the Mediterranean diet) rich in such nutrients as omega-3 fatty acids, some antioxidants and vitamins, and low in saturated fatty acids (SFAs) and trans-fatty acids (TFAs) are inversely associated with low semen quality parameters. In terms of food groups, fish, shellfish and seafood, poultry, cereals, vegetables and fruits, and low-fat dairy products have been positively related to sperm quality. However, diets rich in processed meat, soy foods, potatoes, full-fat dairy products, coffee, alcohol and sugar-sweetened beverages and sweets have been inversely associated with the quality of semen in some studies. The few studies relating male nutrient or food intake and fecundability also suggest that diets rich in red meat, processed meat, tea and caffeine are associated with a lower rate of fecundability. This association is only controversial in the case of alcohol. The potential biological mechanisms linking diet with sperm function and fertility are largely unknown and require further study.

Because an acute hematoma can lead to cauliflower ear, prompt evacuation of the blood is needed to prevent permanent deformity. The outer ear is prone to infections, so antibiotics are usually prescribed. Pressure is applied by bandaging, helping the skin and the cartilage to reconnect. Without medical intervention the ear can suffer serious damage. Disruption of the ear canal is possible. The outer ear may wrinkle, and can become slightly pale due to reduced blood flow; hence the common term "cauliflower ear". Cosmetic procedures are available that can possibly improve the appearance of the ear.

Headgear called a "scrum cap" in rugby, or simply "headgear" or earguard in wrestling and other martial arts, that protects the ears is worn to help prevent this condition. For some athletes, however, a cauliflower ear is considered a badge of courage or experience.

Many normed assessments can be used in evaluating skills in the primary academic domains: reading, including word recognition, fluency, and comprehension; mathematics, including computation and problem solving; and written expression, including handwriting, spelling and composition.

The most commonly used comprehensive achievement tests include the Woodcock-Johnson IV (WJ IV), Wechsler Individual Achievement Test II (WIAT II), the Wide Range Achievement Test III (WRAT III), and the Stanford Achievement Test–10th edition. These tests include measures of many academic domains that are reliable in identifying areas of difficulty.

In the reading domain, there are also specialized tests that can be used to obtain details about specific reading deficits. Assessments that measure multiple domains of reading include Gray's Diagnostic Reading Tests–2nd edition (GDRT II) and the Stanford Diagnostic Reading Assessment. Assessments that measure reading subskills include the Gray Oral Reading Test IV – Fourth Edition (GORT IV), Gray Silent Reading Test, Comprehensive Test of Phonological Processing (CTOPP), Tests of Oral Reading and Comprehension Skills (TORCS), Test of Reading Comprehension 3 (TORC-3), Test of Word Reading Efficiency (TOWRE), and the Test of Reading Fluency. A more comprehensive list of reading assessments may be obtained from the Southwest Educational Development Laboratory.

The purpose of assessment is to determine what is needed for intervention, which also requires consideration of contextual variables and whether there are comorbid disorders that must also be identified and treated, such as behavioral issues or language delays. These contextual variables are often assessed using parent and teacher questionnaire forms that rate the students' behaviors and compares them to standardized norms.

However, caution should be made when suspecting the person with a learning disability may also have dementia, especially as people with Down's syndrome may have the neuroanatomical profile but not the associated clinical signs and symptoms. Examination can be carried out of executive functioning as well as social and cognitive abilities but may need adaptation of standardized tests to take account of special needs.

The medical aspect of a face distortion is usually the case involving the skull, neck, or brain. whatever treatment for the aftermath of a face distortion depends on the condition of the receiver after the event occurs.

Pigment dispersion syndrome (PDS) is an affliction of the eye that can lead to a form of glaucoma known as pigmentary glaucoma. It takes place when pigment cells slough off from the back of the iris and float around in the aqueous humor. Over time, these pigment cells can accumulate in the anterior chamber in such a way that it can begin to clog the trabecular meshwork (the major site of aqueous humour drainage), which can in turn prevent the aqueous humour from draining and therefore increases the pressure inside the eye. With PDS, the intraocular pressure tends to spike at times and then can return to normal. Exercise has been shown to contribute to spikes in pressure as well. When the pressure is great enough to cause damage to the optic nerve, this is called pigmentary glaucoma. As with all types of glaucoma, when damage happens to the optic nerve fibers, the vision loss that occurs is irreversible and painless.

This condition is rare, but occurs most often in Caucasians, particularly men, and the age of onset is relatively low: mid 20s to 40s. As the crystalline lens hardens with age, the lens zonules pull away from the iris and the syndrome lessens and stops. Most sufferers are nearsighted.

There is no cure yet, but pigmentary glaucoma can be managed with eye drops or treated with simple surgeries. One of the surgeries is the YAG laser procedure in which a laser is used to break up the pigment clogs, and reduce pressure. If caught early and treated, chances of glaucoma are greatly reduced. Sufferers are often advised not to engage in high-impact sports such as long-distance running or martial arts, as strong impacts can cause more pigment cells to slough off.

A 2016 Cochrane Review sought to determine the effectiveness of YAG laser iridotomy versus no laser iridotomy for pigment dispersion syndrome and pigmentary glaucoma, in 195 participants, across five studies. No clear benefits in preventing loss of visual field were found for eyes treated with peripheral laser iridotomy. There was weak evidence suggesting that laser iridotomy could be more effective in lowering intraocular pressure in eyes versus no treatment.

Learning disabilities can be categorized by either the type of information processing affected by the disability or by the specific difficulties caused by a processing deficit.

Obstetric ultrasonography can detect fetal abnormalities, detect multiple pregnancies, and improve gestational dating at 24 weeks. The resultant estimated gestational age and due date of the fetus are slightly more accurate than methods based on last menstrual period. Ultrasound is used to measure the nuchal fold in order to screen for Downs syndrome.

Medical imaging may be indicated in pregnancy because of pregnancy complications, intercurrent diseases or routine prenatal care. Magnetic resonance imaging (MRI) without MRI contrast agents as well as obstetric ultrasonography are not associated with any risk for the mother or the fetus, and are the imaging techniques of choice for pregnant women. Projectional radiography, X-ray computed tomography and nuclear medicine imaging result in some degree of ionizing radiation exposure, but in most cases the absorbed doses are not associated with harm to the baby. At higher dosages, effects can include miscarriage, birth defects and intellectual disability.

Blain was an animal disease of unknown etiology that was well known in the eighteenth- and nineteenth centuries. It is unclear whether it is still extant, or what modern disease it corresponds to.

According to Ephraim Chambers' eighteenth-century "Cyclopaedia, or an Universal Dictionary of Arts and Sciences", blain was "a " (in the archaic eighteenth-century sense of the word, meaning "disease") occurring in animals, consisting in a "Bladder growing on the Root of the Tongue against the Wind-Pipe", which "at length swelling, stops the Wind". It was thought to occur "by great chafing, and heating of the Stomach".

Blain is also mentioned in "Cattle: Their Breeds, Management, and Diseases", published in 1836, where it is also identified as "gloss-anthrax". W. C. Spooner's 1888 book "The History, Structure, Economy and Diseases of the Sheep" also identifies blain as being the same as gloss-anthrax.

Modern scholarship suggests that "gloss-anthrax" was not the same disease as modern-day anthrax, but instead could have been foot-and-mouth disease, or a viral infection with a secondary "Fusobacterium necrophorum" infection. It has also been suggested that it may have been due to a variant strain of true anthrax that is no longer in existence. Other sources also report epizootics known as "blain" or "black-blain" in the 13th and 14th centuries, but it is not clear if the disease involved was the same as "gloss-anthrax".

Several movies, as well as some anime, involving boxing, martial arts, or other styles of fighting have scenes involving face distortion. Movies like "Cinderella man", which involves American boxing has a few of these moments. Anime's like Bleach and Naruto contain moments of face distortion as well.

Although often termed a "neurological condition," synesthesia is not listed in either the DSM-IV or the ICD since it most often does not interfere with normal daily functioning. Indeed, most synesthetes report that their experiences are neutral or even pleasant. Like perfect pitch, synesthesia is simply a difference in perceptual experience.

The simplest approach is test-retest reliability over long periods of time, using stimuli of color names, color chips, or a computer-screen color picker providing 16.7 million choices. Synesthetes consistently score around 90% on reliability of associations, even with years between tests. In contrast, non-synesthetes score just 30–40%, even with only a few weeks between tests and a warning that they would be retested.

Grapheme-color synesthetes, as a group, share significant preferences for the color of each letter (e.g. A tends to be red; O tends to be white or black; S tends to be yellow etc.) Nonetheless, there is a great variety in types of synesthesia, and within each type, individuals report differing triggers for their sensations and differing intensities of experiences. This variety means that defining synesthesia in an individual is difficult, and the majority of synesthetes are completely unaware that their experiences have a name.

Neurologist Richard Cytowic identifies the following diagnostic criteria for synesthesia in his "first" edition book. However, the criteria are different in the second book:

1. Synesthesia is involuntary and automatic.

2. Synesthetic perceptions are spatially extended, meaning they often have a sense of "location." For example, synesthetes speak of "looking at" or "going to" a particular place to attend to the experience.

3. Synesthetic percepts are consistent and generic (i.e. simple rather than pictorial).

4. Synesthesia is highly memorable.

5. Synesthesia is laden with affect.

Cytowic's early cases mainly included individuals whose synesthesia was frankly projected outside the body (e.g. on a "screen" in front of one's face). Later research showed that such stark externalization occurs in a minority of synesthetes. Refining this concept, Cytowic and Eagleman differentiated between "localizers" and "non-localizers" to distinguish those synesthetes whose perceptions have a definite sense of spatial quality from those whose perceptions do not.

In "How Everyone Became Depressed: The Rise and Fall of the Nervous Breakdown" (2013), Edward Shorter, a professor of psychiatry and the history of medicine, argues for a return to the old-fashioned concept of nervous illness:

The medication that may be prescribed to someone who has a mental breakdown is based upon the underlying causes, which are sometimes more serious mental disorders. Antidepressants are given to treat depression. Anxiolytics are used for those with anxiety disorders. Antipsychotics are used for schizophrenia and mood stabilizers help with bipolar disorder. Depending upon what caused a person’s mental breakdown, any of these treatments can be helpful for them.

There are several different kinds of therapy that a patient can receive. The most common type of therapy is counseling. This is where the patient is able to talk about whatever is on their mind without worrying about any judgments. Psychotherapy is a very common type of therapy that addresses the current problems in someone’s life and helps them to deal with them. Past experiences may also be explored in this type of therapy. In psychoanalysis therapy, the main focus is a patient’s past experiences so that they can confront these issues and prevent breakdowns in the future. Cognitive behavioral therapy explores how a person behaves and what they are thinking and feeling. If there is anything negative in these three different categories, then this therapy will try to turn them around into positives. Hypnotherapy is where hypnosis is performed and used to help the patient relax. Hypnosis can also be used to figure out why a person acts or feels a certain way, by examining past events that may have caused the breakdown. Expressive therapy focuses on how the patient is able to express their feelings. If the patient has a hard time doing this, expression through the arts is highly recommended. There is also aromatherapy, which consists of herbs to help the patient relax and to try to relieve stress. Yoga and massage may also be included in this therapy that will help the muscles to relax. Meditation is also often recommended. All of these therapies help a person to relax and de-stress and also help to prevent future breakdowns.

The hunched position that often results from complete spinal fusion can have an effect on a person’s gait. Increased spinal kyphosis will lead to a forward and downward shift in center of mass (COM). This shift in COM has been shown to be compensated by increased knee flexion and ankle dorsiflexion. The gait of someone with ankylosing spondylitis often has a cautious pattern because they have decreased ability to absorb shock, and they cannot see the horizon.

Variations of the HLA-B gene increase the risk of developing ankylosing spondylitis, although it is not a diagnostic test. Those with the HLA-B27 variant are at a higher risk than the general population of developing the disorder. HLA-B27, demonstrated in a blood test, can occasionally help with diagnosis, but in itself is not diagnostic of AS in a person with back pain. Over 90% of people that have been diagnosed with AS are HLA-B27 positive, although this ratio varies from population to population (about 50% of African Americans with AS possess HLA-B27 in contrast to the figure of 80% among those with AS who are of Mediterranean descent).

Synesthesia is found in at least 4.4% of the population, as a high estimate, which is equivalent to 1 in 23 people. This study had also concluded that one common form of synesthesia—grapheme-color synesthesia (colored letters and numbers) – is found in more than one percent of the population, and this latter prevalence of graphemes-color synesthesia has now been independently verified in a yet larger sample. Earlier estimates of the prevalence of synesthesia were based on "best-guess" estimations only ("e.g." 1 in 250,000) or had limitations in their methodologies because they required synesthetes to refer themselves for study ("e.g." 1 in 2000) and for this reason the authors of those studies had been moderate in their claims. Also, some individuals will not self-classify as synesthetes because they do not realize that their perceptions are different from those of everyone else.

The most common forms of synesthesia are those that trigger colors, and the most prevalent of all is day-color. Also relatively common is grapheme-color synesthesia. We can think of "prevalence" both in terms of how common is synesthesia (or different forms of synesthesia) within the population, or how common are different forms of synesthesia within synesthetes. So within synesthetes, forms of synesthesia that trigger color also appear to be the most common forms of synesthesia with a prevalence rate of 86% within synesthetes. In another study, music-color is also prevalent at 18–41%. Some of the rarest are reported to be auditory-tactile, mirror-touch, and lexical-gustatory.

There is research to suggest that the likelihood of having synesthesia is greater in people with autism.

Catalepsy is a symptom of certain nervous disorders or conditions such as Parkinson's disease and epilepsy. It is also a characteristic symptom of cocaine withdrawal, as well as one of the features of catatonia. It can be caused by schizophrenia treatment with anti-psychotics, such as haloperidol, and by the anesthetic ketamine. Protein kinase A has been suggested as a mediator of cataleptic behavior.

Symptoms include: rigid body, rigid limbs, limbs staying in same position when moved (waxy flexibility), no response, loss of muscle control, and slowing down of bodily functions, such as breathing.

In the second edition of the Chinese Classification of Mental Disorders (CCMD-2) published by the Chinese Society of Psychiatry the diagnosis of “Qigong Deviation Syndrome” is based upon the following criteria:

- The subject being demonstrably normal before doing qigong exercises

- Psychological and physiological reactions appearing during or after qigong exercises (suggestion and autosuggestion may play an important role in these reactions)

- Complaints of abnormal sensations during or after qigong exercises

- Diagnostic criteria do not meet other mental disorders such as schizophrenia, affective disorder, and neurosis.

Corns and calluses are easier to prevent than to treat. When it is usually not desirable to form a callus, minimizing rubbing and pressure will prevent callus formation. Footwear should be properly fitted, gloves may be worn, and protective pads, rings or skin dressings may be used. People with poor circulation or sensation should check their skin often for signs of rubbing and irritation so they can minimize any damage.

In botany, the term is also used to describe a condition of thickened surfaces of leaves or other plant parts. A callus also can refer to an undifferentiated plant cell mass grown on a culture medium, which can be put into a bioreactor to produce genetically identical cells. This is a type of tissue culture, and can be started from almost any part of the plant, although tissues taken from the vicinity of meristems usually produce the best results.

The term has also been used in orthopedic medicine to describe heterogeneous tissue involved in the intermediate stages of bone healing.

In English, the adjective "callous" means insensitive or unfeeling, similarly to how calluses can cause a loss of pain sensitivity in the affected area.