Endaural phenomena are sounds that are heard without any external acoustic stimulation. Endaural means "in the ear". Phenomena include transient ringing in the ears (that sound like sine tones), white noise-like sounds, and subjective tinnitus. Endaural phenomena need to be distinguished from otoacoustic emissions, in which a person's ear emits sounds. The emitter typically cannot hear the sounds made by his or her ear. Endaural phenomena also need to be distinguished from auditory hallucinations, which are sometimes associated with psychosis.

Alternatively, the disruption could occur during the process of re-externalizing one's inner voice, resulting in an apparent second voice that seems alien to the individual; a problem that would be interpreted as a level four to level one error.

Psychopharmacological treatments include anti-psychotic medications. Psychology research shows that first step in treatment is for the patient to realize that the voices they hear are creation of their own mind. This realization is argued to allow patients to reclaim a measure of control over their lives. Some additional psychological interventions might allow for the process of controlling these phenomena of auditory hallucinations but more research is needed.

Experiences - are characterized by the presence of the following three factors:

- disembodiment, an apparent location of the self outside one's body;

- impression of seeing the world from an elevated and distanced visuo-spatial perspective or extracorporeal, but egocentric visuo-spatial perspective;

- impression of seeing one's own body from this perspective (autoscopy).

Laboratory of Cognitive Neuroscience, École Polytechnique Fédérale de Lausanne, Lausanne, and Department of Neurology, University Hospital, Geneva, Switzerland, have reviewed some of the classical precipitating factors of autoscopy. These are sleep, drug abuse, and general anesthesia as well as neurobiology. They have compared them with recent findings on neurological and neurocognitive mechanisms of the autoscopy. The reviewed data suggest that autoscopic experiences are due to functional disintegration of lower-level multisensory processing and abnormal higher-level self-processing at the temporoparietal junction.

Visual snow, also known as visual static, is a proposed condition in which people see white or black dots in parts or the whole of their visual fields. The problem is typically always present and can last years. The severity of the "snow" differs; and it has been suggested that in some the condition may affect daily life, making it difficult to read, drive, or see in detail. The use of computer screens can exacerbate symptoms.

The cause is unclear. Typically it occurs in people with migraines. The underlying mechanism is believed to involve excessive excitability of neurons within the cortex of the brain. It is commonly confused with floaters, leading to misdiagnosis as well as underdiagnosis.

Medications that may be used include lamotrigine, acetazolamide, or verapamil. But these do not always result in benefits.

Autoscopy is the experience in which an individual perceives the surrounding environment from a different perspective, from a position outside of his or her own body. Autoscopy comes from the ancient Greek ("self") and ("watcher").

Autoscopy has been of interest to humankind from time immemorial and is abundant in the folklore, mythology, and spiritual narratives of most ancient and modern societies. Cases of autoscopy are commonly encountered in modern psychiatric practice. According to neurological research, autoscopic experiences are hallucinations.

People with Geschwind syndrome reported higher rates of atypical or altered sexuality. In approximately half of affected individuals hyposexuality is reported. Less commonly, cases of hypersexuality have been reported.

The cause is unclear. The underlying mechanism is believed to involve excessive excitability of neurons within the cortex of the brain.

Specifically the right lingual gyrus and left cerebellar anterior lobe of the brain.

Persisting visual snow can feature as a leading addition to a migraine complication called persistent aura without infarction, commonly referred to as persistent migraine aura (PMA). In other clinical sub-forms of migraine headache may be absent and the migraine aura may not take the typical form of the zigzagged fortification spectrum, but manifests with a large variety of focal neurological symptoms.

The role of hallucinogens in of visual snow is not clear. Hallucinogen persisting perception disorder (HPPD), a condition caused by hallucinogenic drug use, is sometimes linked to visual snow, but both the connection of visual snow to HPPD and the cause and prevalence of HPPD is disputed. Most of the evidence for both is generally anecdotal, and subject to spotlight fallacy.

This syndrome is predominantly found in young women, but also occurs in children, teenagers and octogenarians.

Uner Tan syndrome, Unertan syndrome or UTS is a syndrome proposed by the Turkish evolutionary biologist Üner Tan. According to Tan, persons affected by this syndrome walk with a quadrupedal locomotion and are afflicted with "primitive" speech and severe mental retardation. Tan postulated that this is an example of "reverse

One study from as early as 1895 reported that approximately 10% of the population experiences hallucinations. A 1996-1999 survey of over 13,000 people reported a much higher figure, with almost 39% of people reporting hallucinatory experiences, 27% of which daytime hallucinations, mostly outside the context of illness or drug use. From this survey, olfactory (smell) and gustatory (taste) hallucinations seem the most common in the general population.

Geschwind syndrome, also known as Gastaut-Geschwind, is a group of behavioral phenomena evident in some people with temporal lobe epilepsy. It is named for one of the first individuals to categorize the symptoms, Norman Geschwind, who published prolifically on the topic from 1973 to 1984. There is controversy surrounding whether it is a true neuropsychiatric disorder. Temporal lobe epilepsy causes chronic, mild, interictal (i.e. between seizures) changes in personality, which slowly intensify over time. Geschwind syndrome includes five primary changes; hypergraphia, hyperreligiosity, atypical (usually reduced) sexuality, circumstantiality, and intensified mental life. Not all symptoms must be present for a diagnosis. Only some people with epilepsy or temporal lobe epilepsy show features of Geschwind syndrome.

Pelopsia is a vision perception disorder in which objects appear nearer than they actually are. Pelopsia can be caused by psychoneurotic phenomena, changes in atmospheric clarity, or sometimes by wearing a corrective lens.

Posterior visual pathway cortical lesions (tumor, abscess, hemorrhage, infarction, arteriovenous malformation, cortical dysplasia, aneurysm) and various seizure causes (hyperglycemia, ion channel mutations, Creutzfeldt–Jakob disease, idiopathic seizures, etc.) cause focal cortical hyperactivity or hyperexcitability, resulting in inappropriate, persistent activation of a visual memory circuit.

Illusory palinopsia is a dysfunction of visual perception, resulting from diffuse, persistent alterations in neuronal excitability that affect physiological mechanisms of light or motion perception. Illusory palinopsia is caused by migraines, HPPD, prescription drugs, head trauma, or may be idiopathic. Trazodone, nefazodone, mirtazepine, topiramate, clomiphene, oral contraceptives, and risperidone have been reported to cause illusory palinopsia. A patient frequently has multiple types of illusory palinopsia, which represent dysfunctions in both light and motion perception. Light and motion are processed via different pathways, suggesting diffuse or global excitability alterations.

The Ulaş family of nineteen from rural southern Turkey has been the primary example of the proposed syndrome. Tan described five members as walking with a quadrupedal gait using their feet and the palms of their hands. In infants, where this is a rare but a normal stage prior and sometimes following bipedal walking, such a gait is called "bear crawl". The affected family members are also severely mentally retarded and their speech is affected. Tan proposed that these are symptoms of Uner Tan syndrome.

In January 2008, Tan reported on another family (four males and two females) located in southern Turkey.

Four other unrelated cases in families are described as having various degrees of UTS. Males may be affected more than females. It is also claimed that some individuals are unaware of time, lack language, have severe mental retardation with no conscious experience, and communicate by using sounds. Two males are unable to stand up, while in other cases, can stand up but cannot make a step when standing. Less severe cases use toe walking, which is a normal phase in child gait development.

Episodes of micropsia or macropsia occur in 9% of adolescents.

10-35% of migraine sufferers experience auras, with 88% of these patients experiencing both visual auras (which include micropsia) and neurological auras.

Micropsia seems to be slightly more common in boys than in girls among children who experience migraines.

Approximately 80% of temporal lobe seizures produce auras that may lead to micropsia or macropsia. They are a common feature of simple partial seizures and usually precede complex partial seizures of temporal lobe origin.

Central Serous Chorioretinopathy (CSCR) which can produce micropsia predominantly affects persons between the ages of 20 and 50. Women appear to be affected more than men by a factor of almost 3 to 1.

Research needs to be performed on the efficacy of the various pharmaceuticals for treating illusory palinopsia. It is unclear if the symptoms' natural history and treatment are influenced by the cause. It is also not clear if there is treatment efficacy overlap for illusory palinopsia and the other co-existing diffuse persistent illusory phenomenon such as visual snow, oscillopsia, dysmetropsia, and halos.

Future advancements in fMRI could potentially further our understanding of hallucinatory palinopsia and visual memory. Increased accuracy in fMRI might also allow for the observation of subtle metabolic or perfusional changes in illusory palinopsia, without the use of ionizing radiation present in CT scans and radioactive isotopes. Studying the psychophysics of light and motion perception could advance our understanding of illusory palinopsia, and vice versa. For example, incorporating patients with visual trailing into motion perception studies could advance our understanding of the mechanisms of visual stability and motion suppression during eye movements (e.g. saccadic suppression).

Meteoropathy (from Greek "meteora", celestial phenomena, and "pathos", feeling, pain, suffering) is a physical condition, or symptom associated with weather conditions such as humidity, temperature or pressure.

Underlying causes may include:

- Han (a Korean culture-related depressive sentiment related to hard life and social unfairness resulting not only from a tragic collective national history, but also from personal traumas)

- prior instances of major depressive disorder

- prior instances of anxiety disorder

- prior instances of adjustment disorder

- prior instances of other somatoform disorders

- repression of feelings of anger/resentment arising from past events

Triggering causes are typically external events, including:

- familial stressors, e.g. spousal infidelity or conflict with in-laws

- witnessing acts/actions/phenomena that conflict with one's own moral and/or ethical principles

The syndrome itself is believed to be the result of the continued repression of feelings of anger without addressing their source. In holistic medicine the containment of anger in hwabyung disturbs the balance of the five bodily elements, resulting in the development of psychosomatic symptoms such as panic, insomnia, and depression after a long period of repressed feelings.

It is possible that hormonal imbalances such as those around the time of menopause may also be an underlying cause of hwabyung in middle-aged women, the most often-diagnosed demographic.

The concept of thought disorder has been criticized as being based on circular or incoherent definitions. For example, thought disorder is inferred from disordered speech, based on the assumption that disordered speech arises because of disordered thought. Incoherence, or word salad, refers to speech that is unconnected and conveys no meaning to the listener.

Furthermore, although thought disorder is typically associated with psychosis, similar phenomena can appear in different disorders, potentially leading to misdiagnosis—for example, in the case of incomplete yet potentially fruitful thought processes.

It has been suggested that individuals with autism spectrum disorders (ASD) display language disturbances like those found in schizophrenia; a 2008 study found that children and adolescents with ASD showed significantly more illogical thinking and loose associations than control subjects. The illogical thinking was related to cognitive functioning and executive control; the loose associations were related to communication symptoms and to parent reports of stress and anxiety.

Paragrammatism is the confused or incomplete use of grammatical structures, found in certain forms of speech disturbance. Paragrammatism is the inability to form grammatically correct sentences. It is characteristic of fluent aphasia, most commonly Receptive aphasia. Paragrammatism is sometimes called "extended paraphasia," although it is different from paraphasia. Paragrammatism is roughly synonymous with "word salad," which concerns the semantic coherence of speech rather than its production.

Compensatory hyperhidrosis is a form of neuropathy. It is encountered in patients with myelopathy, thoracic disease, cerebrovascular disease, nerve trauma or after surgeries. The exact mechanism of the phenomenon is poorly understood. It is attributed to the perception in the hypothalamus (brain) that the body temperature is too high. The sweating is induced to reduce body heat.

Excessive sweating due to nervousness, anger, previous trauma or fear is called hyperhidrosis.

Compensatory hyperhidrosis is the most common side effect of endoscopic thoracic sympathectomy, a surgery to treat severe focal hyperhidrosis, often affecting just one part of the body. It may also be called "rebound" or "reflex hyperhidrosis". In a small number of individuals, compensatory hyperhidrosis following sympathectomy is disruptive, because afflicted individuals may have to change sweat-soaked clothing two or three times a day.

According to Dr Hooshmand, sympathectomy permanently damages the temperature regulatory system. The permanent destruction of thermoregulatory function of the sympathetic nervous system causes latent complications, e.g., RSD in contralateral extremity.

Following surgery for axillary (armpit), palmar (palm) hyperhidrosis (see focal hyperhidrosis) and blushing, the body may sweat excessively at untreated areas, most commonly the lower back and trunk, but can be spread over the total body surface below the level of the cut. The upper part of the body, above the sympathetic chain transection, the body becomes anhidriotic, where the patient is unable to sweat or cool down, which further compromises the body's thermoregulation and can lead to elevated core temperature, overheating and hyperthermia. Below the level of the sympathetic chain interruption, body temperature is significantly lower, creating a stark contrast that can be observed on thermal images. The difference in temperatures between the sympathetically under- and overactive regions can be as high as 10 Celsius.

Parinaud's Syndrome results from injury, either direct or compressive, to the dorsal midbrain. Specifically, compression or ischemic damage of the mesencephalic tectum, including the superior colliculus adjacent oculomotor (origin of cranial nerve III) and Edinger-Westphal nuclei, causing dysfunction to the motor function of the eye.

Classically, it has been associated with three major groups:

1. Young patients with brain tumors in the pineal gland or midbrain: pinealoma (intracranial germinomas) are the most common lesion producing this syndrome.

2. Women in their 20s-30s with multiple sclerosis

3. Older patients following stroke of the upper brainstem

However, any other compression, ischemia or damage to this region can produce these phenomena: obstructive hydrocephalus, midbrain hemorrhage, cerebral arteriovenous malformation, trauma and brainstem toxoplasmosis infection. Neoplasms and giant aneurysms of the posterior fossa have also been associated with the midbrain syndrome.

Vertical supranuclear ophthalmoplegia has also been associated with metabolic disorders, such as Niemann-Pick disease, Wilson's disease, kernicterus, and barbiturate overdose.

Meteoropathy is different from historical conceptions of "air" causing diseases and strongly influencing people's sense of well-being (see Miasma theory of disease).

""Pleasant weather (higher temperature or barometric pressure) was related to higher mood, better memory, and ‘‘"broadened"’’ cognitive style during the spring as time spent outside increased. The same relationships between mood and weather were not observed during other times of year, and indeed hotter weather was associated with lower mood in the summer.""

There are symptoms that are mechanism-based that are associated with hallucinations. These include superficial pressure and stabbing pain. Others include a burning-like sensation or electric shock feeling. Human studies of these symptoms remain mostly unclear unlike similar studies in animals.