Sensory processing disorder since 1994 is accepted in the Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood (DC:0-3R) and is not recognized as a mental disorder in medical manuals such as the ICD-10 or the DSM-5.

Diagnosis is primarily arrived at by the use of standardized tests, standardized questionnaires, expert observational scales, and free play observation at an occupational therapy gym. Observation of functional activities might be carried at school and home as well. Some scales that are not exclusively used in SPD evaluations are used to measure visual perception, function, neurology and motor skills.

Depending on the country, diagnosis is made by different professionals, such as occupational therapists, psychologists, learning specialists, physiotherapists and/or speech and language therapists. In some countries it is recommended to have a full psychological and neurological evaluation if symptoms are too severe.

It is estimated that up to 16.5% of elementary school aged children present elevated SOR behaviors in the tactile or auditory modalities. However, this figure might represent an underestimation of Sensory Over Responsivity prevalence, since this study did not include children with developmental disorders or those delivered preterm, who are more likely to present it.

This figure is, nonetheless, larger than what previous studies with smaller samples had shown: an estimate of 5–13% of elementary school aged children.

Incidence for the remaining subtypes is currently unknown.

Sensory processing sensitivity (SPS), a personality trait, a high measure of which defines a highly sensitive person (HSP), has been described as having hypersensitivity to external stimuli, a greater depth of cognitive processing, and high emotional reactivity. The terms SPS and HSP were coined in the mid-1990s by psychologists Elaine Aron and husband Arthur Aron, with SPS being measured by Aron's Highly Sensitive Person Scale (HSPS) questionnaire. Other researchers have applied various other terms to denote this responsiveness to stimuli that is evidenced in humans and other species.

According to the Arons and colleagues, people with high SPS comprise about 15–20% of the population and are thought to process sensory data more deeply due to the nature of their central nervous system. Although many researchers consistently related high SPS to negative outcomes, Aron and colleagues state that high SPS is a personality trait and not a disorder; other researchers have associated it with increased responsiveness to both positive and negative influences.

Data from the 2001–02 National Epidemiologic Survey on Alcohol and Related Conditions indicates a prevalence rate of 2.36% in the American general population. It appears to occur with equal frequency in males and females. In one study, it was seen in 14.7% of psychiatric outpatients.

Elaine Aron's book "The Highly Sensitive Person" was published in 1996. In 1997 Elaine and Arthur Aron formally identified "sensory processing sensitivity" (SPS), the scientific term for highly sensitive or hypersensitivity, as the defining trait of highly sensitive persons (HSPs). By way of definition, Aron & Aron (1997) wrote that "sensory processing" here refers not to the sense organs as such, but to what occurs as sensory information is transmitted to or processed in the brain. They assert that the trait is not a disorder but an innate survival strategy that has both advantages and disadvantages.

Aron's professional journal articles and self-help publications have focused on distinguishing high SPS from socially behavior and disorders with which high SPS can be confused; overcoming the social unacceptability that can cause low self-esteem; and emphasizing the advantages of high SPS to balance the disadvantages emphasized by others.

In 2015 Elizabeth Bernstein wrote in "The Wall Street Journal" that HSPs were "having a moment," noting that several hundred research studies had been conducted on topics related to HSPs' high sensitivity, and that a First International Scientific Conference on High Sensitivity or Sensory Processing Sensitivity had been held at the Vrije Universiteit Brussel. By 2015, more than a million copies of "The Highly Sensitive Person" had been sold.

Being a personality disorder, which are usually chronic and long-lasting mental conditions, avoidant personality disorder is not expected to improve with time without treatment. It is a poorly studied personality disorder and in light of prevalence rates, societal costs, and the current state of research, AvPD qualifies as a neglected disorder.

At the time of first PANS presentation, note any family history of pharyngitis, impetigo, perianal dermatitis, and GAS infections. If possible, family members should have a throat swab cultured for GAS. Ongoing vigilance against GAS infections in any of the patient’s close contacts is important, as symptom exacerbations have been reported following exposure to a sibling with GAS (even when the PANDAS patient had no evidence of infection). Prompt medical attention to symptoms suggestive of streptococcal infection is important not only to protect the patient, but also siblings, who may be at an increased genetic risk for PANS.

1. SCAN is the most common tool for diagnosing APD, and it also standardized. It is composed for four subsets: discrimination of monaurally presented single words against background noise, acoustically degraded single words, dichotically presented single words, sentence stimuli. Different versions of the test are used depending on the age of the patient.

2. Random Gap Detection Test (RGDT) is also a standardized test. It assesses an individual’s gap detection threshold of tones and white noise. The exam includes stimuli at four different frequencies (500, 1000, 2000, and 4000 Hz) and white noise clicks of 50 ms duration. It is a useful test because it provides an index of auditory temporal resolution. In children, an overall gap detection threshold greater than 20 ms means they have failed.

3. Gaps in Noise Test (GIN) also measures temporal resolution by testing the patient's gap detection threshold in white noise.

4. Pitch Patterns Sequence Test (PPT) and Duration Patterns Sequence Test (DPT) measure auditory pattern identification. The PPS has s series of three tones presented at either of two pitches (high or low). Meanwhile, the DPS has a series of three tones that vary in duration rather than pitch (long or short). Patients are then asked to describe the pattern of pitches presented.

A consortium of academic clinicians and scientists was convened in 2013 to develop more defined diagnostic guidelines for this disorder in anticipation of furthering research, clinical trials, and clinical care for this patient subgroup. A second consortium meeting was convened at NIMH in 2014 to develop preliminary treatment guidelines. The following are the members of the PRC

It has been discovered that APD and ADHD present overlapping symptoms. Below is a ranked order of behavioral symptoms that are most frequently observed in each disorder. Professionals evaluated the overlap of symptoms between the two disorders. The order below is of symptoms that are almost always observed. This chart proves that although the symptoms listed are different, it is easy to get confused between many of them.

There is a high rate of co-occurrence between AD/HD and CAPD. Research shows that 84% of children with APD have confirmed or suspected ADHD. Co-occurrence between ADHD and APD is 41% for children with confirmed diagnosis of ADHD, and 43% for children suspected of having ADHD.

The International Statistical Classification of Diseases and Related Health Problems (ICD), maintained by the World Health Organization, does not recognize multiple chemical sensitivity or environmental sensitivity as a valid diagnosis. The Australian Department of Health recognizes that sometimes debilitating symptoms are attributed to MCS but notes that diagnosis, treatment, and any underlying mechanism remain uncertain. The German Institute for Medical Documentation and Information recognizes MCS as a physical disease and is subsequentially recognized in Austria. The American Medical Association does not recognize MCS as an organic disease because of the lack of scientific evidence supporting a cause-and-effect relationship between very low level exposure and the symptoms of MCS. The American Academy of Allergy, Asthma, and Immunology, the California Medical Association, the American College of Physicians, and the International Society of Regulatory Toxicology and Pharmacology also do not recognize MCS. The US Occupational Safety and Health Administration (OSHA) indicates that MCS is highly controversial and that there is insufficient scientific evidence to explain the relationship between the suggested causes of MCS and its symptoms. OSHA recommends evaluation by a physician knowledgeable of the symptoms presented.

In response to a WHO call for papers at the 5th Paris Appeal Congress of Environmental Idiopathic Intolerance conference that took place in Belgium on the 18th of May, a report that was generally supportive quoted a number of international practitioners. This was provisionally accepted by the Spanish health ministry, and later found proven by a judge in the case of a plumber in the Province of Castellón

MCS is a diagnosis of exclusion, and the first step in diagnosing a potential MCS sufferer is to identify and treat all other conditions which are present and which often explain the reported symptoms. For example, depression, allergy, thyroid disorders, orthostatic syndromes, lupus, hypercalcemia, and anxiety need to be carefully evaluated and, if present, properly treated. The "gold standard" procedure for identifying a person who has MCS is to test response to the random introduction of chemicals the patient has self-identified as relevant. This may be done in a carefully designed challenge booth to eliminate the possibility of contaminants in the room. Chemicals and controls, sometimes called prompts, are introduced in a random method, usually scent-masked. The test subject does not know when a prompt is being given. Objective and subjective responses are measured. Objective measures, such as the galvanic skin response indicate psychological arousal, such as fear, anxiety, or anger. Subjective responses include patient self-reports. A diagnosis of MCS can only be justified when the subject cannot consciously distinguish between chemicals and controls, and when responses are consistently present with exposure to chemicals and consistently absent when prompted by a control.

A 1999 consensus statement recommends that MCS be diagnosed according to six standardized criteria:

1. Symptoms are reproducible with repeated (chemical) exposures

2. The condition has persisted for a significant period of time

3. Low levels of exposure (lower than previously or commonly tolerated) result in manifestations of the syndrome ("i.e." increased sensitivity)

4. The symptoms improve or resolve completely when the triggering chemicals are removed

5. Responses often occur to multiple chemically unrelated substances

6. Symptoms involve multiple-organ symptoms (runny nose, itchy eyes, headache, scratchy throat, ear ache, scalp pain, mental confusion or sleepiness, palpitations of the heart, upset stomach, nausea and/or diarrhea, abdominal cramping, aching joints).

Developmental coordination disorder is a lifelong neurological condition that is more common in males than in females, with a ratio of approximately four males to every female. The exact proportion of people with the disorder is unknown since the disorder can be difficult to detect due to a lack of specific laboratory tests, thus making diagnosis of the condition one of elimination of all other possible causes/diseases. Approximately 5–6% of children are affected by this condition.

Assessments for developmental coordination disorder typically require a developmental history, detailing ages at which significant developmental milestones, such as crawling and walking, occurred. Motor skills screening includes activities designed to indicate developmental coordination disorder, including balancing, physical sequencing, touch sensitivity, and variations on walking activities.

The American Psychiatric Association has four primary inclusive diagnostic criteria for determining if a child has developmental coordination disorder.

The criteria are as follows:

1. Motor Coordination will be greatly reduced, although the intelligence of the child is normal for the age.

2. The difficulties the child experiences with motor coordination or planning interfere with the child's daily life.

3. The difficulties with coordination are not due to any other medical condition

4. If the child does also experience comorbidities such as mental retardation; motor coordination is still disproportionally affected.

Screening tests which can be used to assess developmental coordination disorder include:-

- Movement Assessment Battery for Children (Movement-ABC – Movement-ABC 2)

- Peabody Developmental Motor Scales- Second Edition (PDMS-2)

- Bruininks-Oseretsky Test of Motor Proficiency (BOTMP-BOT-2)

- Motoriktest für vier- bis sechsjährige Kinder (MOT 4-6)

- Körperkoordinationtest für Kinder (KTK)

- Test of Gross Motor Development, Second Edition (TGMD-2)

- Maastrichtse Motoriek Test (MMT)

- Wechsler Adult Intelligence Scale (WAIS-IV)

- Wechsler Individual Achievement Test (WAIT-II)

- Test of Word Reading Efficiency (TOWRE-2)

- Developmental Coordination Disorder Questionnaire (DCD-Q)

- Children's Self-Perceptions of Adequacy in, and Predilection for Physical Activity (CSAPPA)

Currently there is no single gold standard assessment test.

A baseline motor assessment establishes the starting point for developmental intervention programs. Comparing children to normal rates of development may help to establish areas of significant difficulty.

However, research in the "British Journal of Special Education" has shown that knowledge is severely limited in many who should be trained to recognise and respond to various difficulties, including developmental coordination disorder, dyslexia and deficits in attention, motor control and perception (DAMP). The earlier that difficulties are noted and timely assessments occur, the quicker intervention can begin. A teacher or GP could miss a diagnosis if they are only applying a cursory knowledge.

"Teachers will not be able to recognise or accommodate the child with learning difficulties in class if their knowledge is limited. Similarly GPs will find it difficult to detect and appropriately refer children with learning difficulties."

Multiple complex developmental disorder is likely to be caused by a number of different various genetic factors. Each individual with MCDD is unique from one another and displays different symptoms. Various neuropsychological disorders can also be found in family members of people with MCDD.

Thought insertion is defined by the ICD-10 as feeling as if one's thoughts are not one's own, but rather belong to someone else and have been inserted into one's mind. The person experiencing thought insertion will not necessarily know where the thought is coming from, but is able to distinguish between their own thoughts and those inserted into their minds. However, patients do not experience all thoughts as inserted, only certain ones, normally following a similar content or pattern. This phenomenon is classified as a delusion. A person with this delusional belief is convinced of the veracity of their beliefs and is unwilling to accept such diagnosis.

Thought insertion is a common symptom of psychosis and occurs in many mental disorders and other medical conditions. However, thought insertion is most commonly associated with schizophrenia. Thought insertion, along with thought broadcasting, thought withdrawal, thought blocking and other first rank symptoms, is a primary symptom and should not be confused with the delusional explanation given by the respondent. Although normally associated with some form of psychopathology, thought insertion can also be experienced in those considered nonpathological, usually in spiritual contexts, but also in culturally influenced practices such as mediumship and automatic writing.

Examples of thought insertion:

"She said that sometimes it seemed to be her own thought 'but I don't get the feeling that it is'. She said her 'own thoughts might say the same thing', 'but the feeling isn't the same', 'the feeling is that it is somebody else's'"

"I look out the window and I think that the garden looks nice and the grass looks cool, but the thoughts of Eamonn Andrews come into my mind. There are no other thoughts there, only his. He treats my mind like a screen and flashes thoughts onto it like you flash a picture"

"The subject has thoughts that she thinks are the thoughts of other people, somehow occurring in her own mind. It is not that the subject thinks that other people are making her think certain thoughts as if by hypnosis or psychokinesis, but that other people think the thoughts using the subject's mind as a psychological medium."

The current diagnostic criteria for MCDD are a matter of debate due to it not being in the DSM-IV or ICD-10. Various websites contain various diagnostic criteria. At least three of the following categories should be present. Co-occurring clusters of symptoms must also not be better explained by being symptoms of another disorder such as experiencing mood swings due to autism, cognitive difficulties due to schizophrenia, and so on. The exact diagnostic criteria for MCDD remain unclear but may be a useful diagnosis for people who do not fall into any specific category. It could also be argued that MCDD is a vague and unhelpful term for these patients.

Sensory dysfunction disorder is a reported neurological disorder of information processing, characterized by difficulty in understanding and responding appropriately to sensory inputs. Sensory dysfunction disorder is not recognized by the American Medical Association. "Sensory processing (SP) difficulties have been reported in as many as 95% of children with autism, however, empirical research examining the existence of specific patterns of SP difficulties within this population is scarce."

The brain receives messages from the body's sensory systems, which informs the brain of what is going on around and to a person's body. If one or more of these systems become overstimulated, it may result in what is known as Sensory Dysfunction Disorder. An example of a response to overstimulation is expressed by A. Jean Ayres, in "Sensory Integration and the Child: Understanding Hidden Sensory Challenges". She writes, "When the flow of sensations is disorganized, life can be like a rush-hour traffic jam” (p. 289). The following sensory systems are broken down into individual categories to better understand the impact a sensitivity can have on an individual.

Most of the treatments for thought insertion are not specific to the symptom, but rather the symptom is treated through treatment of the psychopathology that causes it. However, one case report considers a way to manage thought insertion through performing thoughts as motor actions of speech. In other words, the patient would speak his thoughts out loud in order to re-give himself the feeling of agency as he could hear himself speaking and then contributing the thought to himself.

There are ways that children with Sensory Dysfunction Disorder may still have fun. The book "The Out-of-Sync Child Has Fun Activities for Kids with Sensory Processing Disorder", written by Carol Stock Kranowitz, M.A., provides different activities for the various sensory systems. These activities can be tools to help strengthen these senses.

Serotonin and norepinephrine reuptake inhibitor, venlafaxine, were given to case study KS four months after initial stroke that started symptoms of witzelsucht. Changes back to his original behavior were noticeable after daily dose of 37.5 mg of venlafaxine for two weeks. In subsequent two months, inappropriate jokes and hypersexual behavior were rarely noticed. Due to the rareness of this disorder, not much research into potential treatments has been conducted.

Loss of language and skills related to social interaction and self-care are serious. The affected children face ongoing disabilities in certain areas and require long term care. Treatment of CDD involves both behavior therapy, environmental therapy and medications.

- Behavior therapy: The main aim of Applied Behavior Analysis (ABA) is to systematically teach the child to relearn language, self-care and social skills. The treatment programs designed in this respect "use a system of rewards to reinforce desirable behaviors and discourage problem behavior." ABA programs may be designed by a board-certified specialist in behavior analysis called a "BCBA" (Board Certified Behavior Analyst), but ABA is also widely used by a number of other health care personnel from different fields like psychologists, speech therapists, physical therapists and occupational therapists with differing levels of expertise. Parents, teachers and caregivers are instructed to use these behavior therapy methods at all times.

- Environmental Therapy: Sensory Enrichment Therapy uses enrichment of the sensory experience to improve symptoms in autism, many of which are common to CDD.

- Medications: There are no medications available to directly treat CDD. Antipsychotic medications are used to treat severe behavior problems like aggressive stance and repetitive behavior patterns. Anticonvulsant medications are used to control seizures.

Treatment consists of finding ways to bring the patient's attention toward the left, usually done incrementally, by going just a few degrees past midline, and progressing from there. Rehabilitation of neglect is often carried out by neuropsychologists, occupational therapist,

speech-language pathologists, neurologic music therapists, physical therapists, optometrists and orthoptists.

Forms of treatment that have been tested with variable reports of success include prismatic adaptation, where a prism lens is worn to pull the vision of the patient towards the left, constrained movement therapy where the "good" limb is constrained in a sling to encourage use of the contralesional limb. Eye-patching has similarly been used, placing a patch over the "good" eye. Pharmaceutical treatments have mostly focused on dopaminergic therapies such as bromocriptine, levodopa, and amphetamines, though these tests have had mixed results, helping in some cases and accentuating hemispatial neglect in others. Caloric vestibular stimulation (CVS) has been shown to bring about a brief remission in some cases. however this technique has been known to elicit unpleasant side-effects such as nystagmus, vertigo and vomiting.

A study done by Schindler and colleagues examined the use of neck muscle vibration on the contralesional posterior neck muscles to induce diversion of gaze from the subjective straight ahead. Subjects received 15 consecutive treatment sessions and were evaluated on different aspects of the neglect disorder including perception of midline, and scanning deficits. The study found that there is evidence that neck muscle stimulation may work, especially if combined with visual scanning techniques. The improvement was evident 2 months after the completion of treatment.

Other areas of emerging treatment options include the use of prisms, visual scanning training, mental imagery training, video feedback training, trunk rotation, galvanic vestibular stimulation (GVS), transcranial magnetic stimulation (TMS) and transcranial direct-current stimulation (tDCS). Of these emerging treatment options, the most studied intervention is prism adaptation and there is evidence of relatively long-term functional gains from comparatively short-term usage. However, all of these treatment interventions (particularly the stimulation techniques) are relatively new and randomised, controlled trial evidence is still limited. Further research is mandatory in this field of research in order to provide more support in evidence-based practice.

In a review article by Pierce & Buxbaum (2002), they concluded that the evidence for Hemispheric Activation Approaches, which focuses on moving the limb on the side of the neglect, has conflicting evidence in the literature. The authors note that a possible limitation in this approach is the requirement for the patients to actively move the neglected limb, which may not be possible for many patients. Constraint-Induced Therapy (CIT), appears to be an effective, long-term treatment for improving neglect in various studies. However, the use of CIT is limited to patients who have active control of wrist and hand extension. Prism Glasses, Hemispatial Glasses, and Eye-Patching have all appear to be effective in improving performance on neglect tests. Caloric Stimulation treatment appears to be effective in improving neglect; however, the effects are generally short-term. The review also suggests that Optokinetic Stimulation is effective in improving position sense, motor skills, body orientation, and perceptual neglect on a short-term basis. As with Caloric Stimulation treatment, long-term studies will be necessary to show its effectiveness. A few Trunk Rotation Therapy studies suggest its effectiveness in improving performance on neglect tests as well as the Functional Independence Measure (FIM). Some less studied treatment possibilities include treatments that target Dorsal Stream of visual processing, Mental Imagery Training, and Neck Vibration Therapy. Trunk rotation therapies aimed at improving postural disorders and balance deficits in patients with unilateral neglect, have demonstrated optimistic results in regaining voluntary trunk control when using specific postural rehabilitative devices. One such device is the Bon Saint Côme apparatus, which uses spatial exploratory tasks in combination with auditory and visual feedback mechanisms to develop trunk control. The Bon Saint Côme device has been shown to be effective with hemiplegic subjects due to the combination of trunk stability exercises, along with the cognitive requirements needed to perform the postural tasks.

A study on comorbidity of GAD and other depressive disorders has shown that treatment is not more or less effective when there is some sort of comorbidity of another disorder. The severity of symptoms did not affect the outcome of the treatment process in these cases.

Witzelsucht (from the German "witzeln", meaning to joke or wisecrack, and "sucht", meaning addiction or yearning) is a set of rare neurological symptoms characterized by a tendency to make puns, or tell inappropriate jokes or pointless stories in socially inappropriate situations. A less common symptom is hypersexuality, the tendency to make sexual comments at inappropriate times or situations. Patients do not understand that their behavior is abnormal, therefore are nonresponsive to others' reactions. This disorder is most commonly seen in patients with frontal lobe damage, particularly right frontal lobe tumors or trauma. The disorder remains named in accordance with its reviewed definition by German neurologist Hermann Oppenheim; its first description as the less focused "Moria" ("stupidity"), by German neurologist Moritz Jastrowitz, was in 1888.

Due to similarity of symptoms of the disorder to the mannerisms of Batman's arch-rival Joker, it is sometimes known as 'The Joker Syndrome'