List of symptoms that has been observed in those with autistic catatonia:

- Stupor

- Mutism

- Hyperactivity

- Agitation

- Excitement

- Posing

- Negativism

- Rigidity

- Waxy flexibility

- Automatic obedience

- Combativeness (during excitement)

- Aggressivity

- Stereotypies

- Tics

- Grimacing

- Echolalia

- Echopraxia

- Perseveration

- Verbigeration

- Staring

- Withdrawal

- Immobility

- Challenging behaviour

- Tremor

- Slowness

- Amotivation

- Grasp reflex

- Mannerism

- Gaze fixation

- Choreoathetoid movements of the trunk and extremities

- Autonomic instability (during excitement)

- Cannot start actions

- Cannot stop actions (if during excitement episodes needs acute psychiatric care)

- Freezing

- Impulsivity

- Bizarre/psychotic

- Sleep problems

- Urinary or Fecal incontinence

- Odd gait

- Passivity

- Reversal of day and night

- Eyerolling

- Stiff muscles

- Catalepsy

- Physiological pillow

- Difficulty crossing lines

- Gegenhalten

- Mitgehen

- Mitmachen

- Ambitendency

- Rituals

Because these are frequently found in cases of autistic disorders, criteria could be met for multiple neurological disorders, or cause severe symptoms.

Some examples include:

1. Learning difficulties symptoms such as dyslexia, dysgraphia, dyscalcula, NVLD, slow learning, poor memory, etc.

2. AD/HD symptoms such as poor concentration, poor decision making, poor judgement, impulsiveness, difficulty sitting still, etc.

3. Synesthesia.

4. Neurological sleep disorders such as narcolepsy, insomnia, circadian rhythm disorder, etc.

5. Conditions affecting perceptions and/or cognition, such as agnosia, aphasia, etc.

6. Tourette syndrome or Tic disorder.

7. Epilepsy or Seizure disorder.

8. Parkinsonian syndrome features such as tremors, stiff movements, etc.

Neuroleptic induced deficit syndrome is principally characterized by the same symptoms that constitute the negative symptoms of schizophrenia: emotional blunting, apathy, hypobulia, anhedonia, indifference, difficulty in thinking, difficulty or total inability in concentrating, lack of initiative, attention deficits, and desocialization. This can easily lead to misdiagnosis and mistreatment. Instead of decreasing the antipsychotic, the doctor may increase their dose to try to "improve" what they perceive to be negative symptoms of schizophrenia, rather than antipsychotic side effects. The concept of neuroleptic induced deficit syndrome was initially presented for schizophrenia, and it has rarely been associated in other mental disorders. In recent years, atypical neuroleptics are being more often managed to patients with bipolar disorder, so some studies about neuroleptic-induced deficit syndrome in bipolar disorder patients now available.

There are significant difficulties in the differential diagnosis of primary negative symptoms and neuroleptic deficiency syndrome (secondary negative symptoms), as well as depression.

Treatment consists of high-dose lorazepam or in some cases ECT. The response to the treatment is usually good, especially if detected early

The winter-over syndrome is a condition found in individuals who "winter-over" throughout the Antarctic (or Arctic) winter. It has been observed in inhabitants of research stations in Antarctica, as well as in polar bases such as Thule, Alert and Eureka. It consists of a variety of behavioral and medical disturbances, including irritability, depression, insomnia, absentmindedness, aggressive behavior, and irritable bowel syndrome.

Possible contributing causes of winter-over syndrome include stress, social isolation, subsyndromal seasonal affective disorder and polar T syndrome.

Masked depression (MD) was a proposed form of atypical depression in which somatic symptoms or behavioural disturbances dominate the clinical picture and disguise the underlying affective disorder. The concept is not currently supported by the mental health profession.

Depressive Disorder Not Otherwise Specified (DD-NOS) is designated by the code "311" in the DSM-IV for depressive disorders that are impairing but do not fit any of the officially specified diagnoses. According to the DSM-IV, DD-NOS encompasses "any depressive disorder that does not meet the criteria for a specific disorder." In the DSM-5, it is called unspecified depressive disorder.

Examples of disorders in this category include those sometimes described as minor depressive disorder and recurrent brief depression.

"Depression" refers to a spectrum of disturbances in mood that vary from mild to severe and from short periods to constant illness. DD-NOS is diagnosed if a patients symptoms fail to meet the criteria more common depressive disorders such as major depressive disorder or dysthymia. Although DD-NOS shares similar symptoms to dysthymia, dysthymia is classified by a period of at least 2 years of constantly recurring depressed mood, where as DD-NOS is classified by much shorter periods of depressed moods.

For most people who suffer the condition, their life will be significantly affected. DD-NOS can make many aspects of a person's daily life difficult to manage, inhibiting their ability to enjoy the things that used to make them happy. Sufferers of the disorder tend to isolate themselves from their friends and families, lose interest in some activities, and experience behavioural changes and sleeping disorders. Some sufferers also experience suicidal tendencies or suicide attempts. In addition to having these symptoms, a diagnosis of DD-NOS will only be made if the symptoms cause significant distress or impairment in social, occupational, or other important areas of functioning. For the diagnosis to be accurate, a psychiatrist is required to spend extensive time with the patient.

Symptoms of the disorder may arise due to several reasons. These include:

- Distress due to medical conditions

- Environmental effects and situations

However, the effects of drugs or medication or bereavement are not classified under the diagnosis.

A person will not be diagnosed with the condition if they have or have had any of the following: a major depressive episode, manic episode, mixed episode or hypomanic episode.

A diagnosis of the disorder will look like: "Depressive Disorder NOS 311".

Paraphrenia (from – beside, near + φρήν – intellect, mind) is a mental disorder characterized by an organized system of paranoid delusions with or without hallucinations (the positive symptoms of schizophrenia) without deterioration of intellect or personality (its negative symptom).

This disorder is also distinguished from schizophrenia by a lower hereditary occurrence, less premorbid maladjustment, and a slower rate of progression. Onset of symptoms generally occurs later in life, near the age of 60. The prevalence of the disorder among the elderly is between 0.1 and 4%

Paraphrenia is not included in the DSM-5; psychiatrists often diagnose patients presenting with paraphrenia as having atypical psychoses, delusional disorder, psychoses not otherwise specified, schizoaffective disorders, and persistent persecutory states of older adults. Recently, mental health professionals have also been classifying paraphrenia as very late-onset schizophrenia-like psychosis.

In the Russian psychiatric manuals paraphrenia (or paraphrenic syndrome) is the last stage of development of paranoid schizophrenia. "Systematized paraphrenia" (with systematized delusions i. e. delusions with complex logical structure) and "expansive-paranoid paraphrenia" (with expansive/grandiose delusions and persecutory delusions) are the variants of paranoid schizophrenia (). You see sometimes "systematized paraphrenia" with delusional disorder ().

Depressive mixed states occur when patients experience depression and non-euphoric, usually subsyndromal, hypomania at the same time. As mentioned previously, it is particularly difficult to diagnose BP-II when a patient is in this state.

In a mixed state, mood is depressed, but the following symptoms of hypomania present as well:

- Irritability

- Mental overactivity

- Behavioral overactivity

Mixed states are associated with greater levels of suicidality than non-mixed depression. Antidepressants may increase this risk.

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

Somatic manifestations of MD are distinguished by an extreme diversity and include headaches, back pain, abdominal pain etc. Pathological behaviour masking depression may take the form of compulsive gambling, compulsive work, changes in arousal or orgasmic function, decreased libido or, on the contrary, impulsive sexual behaviour, alcoholism, drug addiction and more.

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.

The main symptoms of paraphrenia are paranoid delusions and hallucinations. The delusions often involve the individual being the subject of persecution, although they can also be erotic, hypochondriacal, or grandiose in nature. The majority of hallucinations associated with paraphrenia are auditory, with 75% of patients reporting such an experience; however, visual, tactile, and olfactory hallucinations have also been reported. The paranoia and hallucinations can combine in the form of “threatening or accusatory voices coming from neighbouring houses [and] are frequently reported by the patients as disturbing and undeserved". Patients also present with a lack of symptoms commonly found in other mental disorders similar to paraphrenia. There is no significant deterioration of intellect, personality, or habits and patients often remain clean and mostly self-sufficient. Patients also remain oriented well in time and space.

Paraphrenia is different from schizophrenia because, while both disorders result in delusions and hallucinations, individuals with schizophrenia exhibit changes and deterioration of personality whereas individuals with paraphrenia maintain a well-preserved personality and affective response.

It is during depressive episodes that BP-II patients often seek help. Symptoms may be syndromal or subsyndromal. Depressive BP-II symptoms may include five or more of the below symptoms (at least one of them must be either depressed mood or loss of interest/pleasure). In order to be diagnosed, they need to be present only during the same two-week period, as a change from previous hypomanic functioning:

- Depressed mood most of the day, nearly every day, as indicated by either subjective report (e.g., feels sad, empty, or hopeless) or observation made by others (e.g., appears tearful). (Note: In children and adolescents, can be irritable mood.)

- Markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly every day (as indicated by either subjective account or observation).

- Significant weight loss when not dieting or weight gain (e.g., a change of more than 5% of body weight in a month), or decrease or increase in appetite nearly every day. (Note: In children, consider failure to make expected weight gain.)

- Insomnia or hypersomnia nearly every day.

- Psychomotor agitation or retardation nearly every day (observable by others; not merely subjective feelings of restlessness or being slowed down).

- Fatigue or loss of energy nearly every day.

- Feelings of worthlessness or excessive or inappropriate guilt nearly every day (not merely self-reproach or guilt about being sick).

- Diminished ability to think or concentrate, possible irritability or indecisiveness, nearly every day (either by subjective account or as observed by others).

- Recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, a suicide attempt, or a specific plan for committing suicide.

Evidence also suggests that BP-II is strongly associated with atypical depression. Essentially, this means that many BP-II patients exhibit reverse vegetative symptoms. BP-II patients may have a tendency to oversleep and overeat, while typically depressed patients sleep and eat less than usual.

The affective spectrum is a spectrum of affective disorders (mood disorders). It is a grouping of related psychiatric and medical disorders which may accompany bipolar, unipolar, and schizoaffective disorders at statistically higher rates than would normally be expected. These disorders are identified by a common positive response to the same types of pharmacologic treatments. They also aggregate strongly in families and may therefore share common heritable underlying physiologic anomalies.

Affective spectrum disorders include:

- Attention deficit hyperactivity disorder

- Bipolar disorder

- Body dysmorphic disorder

- Bulimia nervosa and other eating disorders

- Cataplexy

- Dysthymia

- Generalized anxiety disorder

- Hypersexuality

- Irritable bowel syndrome

- Impulse-control disorders

- Kleptomania

- Migraine

- Major depressive disorder

- Obsessive-compulsive disorder

- Oppositional defiant disorder

- Panic disorder

- Posttraumatic stress disorder

- Premenstrual dysphoric disorder

- Social anxiety disorder

- Fibromyalgia

The following may also be part of the spectrum accompanying affective disorders.

- Chronic pain

- Intermittent explosive disorder

- Pathological gambling

- Personality disorder

- Pyromania

- Substance abuse and addiction (includes alcoholism)

- Trichotillomania

Also, there are now studies linking heart disease.

Many of the terms above overlap. The American Psychiatric Association's definitions of these terms can be found in the "Diagnostic and Statistical Manual of Mental Disorders" (DSM).

Neuroleptic-induced deficit syndrome (NIDS) is a psychopathological syndrome that develops in some patients who take high doses of an antipsychotic for an extended time. It is most often caused by high-potency typical antipsychotics, but can also be caused by high doses of many atypicals, especially those closer in profile to typical ones (that have higher D dopamine receptor affinity and relatively low 5-HT serotonin receptor binding affinity), like risperidone and amisulpride.

Bipolar I disorder (BD-I; pronounced "type one bipolar disorder") is a bipolar spectrum disorder characterized by the occurrence of at least one manic or mixed episode. Most patients also, at other times, have one or more depressive episodes, and all experience a hypomanic stage before progressing to full mania.

It is a type of bipolar disorder, and conforms to the classic concept of manic-depressive illness, which can include psychosis during mood episodes. The difference with bipolar II disorder is that the latter requires that the individual must never have experienced a full manic or mixed-manic episode - only less severe hypomanic episode(s).

Mania is a distinct period of at least one week of elevated or irritable mood, which can range from euphoria to delirium, and those experiencing hypo- or mania may exhibit three or more of the following behaviors: speak in a rapid, uninterruptible manner, short attention span, racing thoughts, increased goal-oriented activities, agitation, or they may exhibit behaviors characterized as impulsive or high-risk, such as hypersexuality or excessive spending. To meet the definition for a manic episode, these behaviors must impair the individual's ability to socialize or work. If untreated, a manic episode usually lasts three to six months.

People with hypomania or mania may experience a decreased need of sleep, impaired judgment, and speak excessively and very rapidly. Manic individuals often have a history of substance abuse developed over years as a form of "self-medication". At the more extreme, a person in a full blown manic state can experience psychosis; a break with reality, a state in which thinking is affected along with mood. They may feel unstoppable, or as if they have been "chosen" and are on a "special mission", or have other grandiose or delusional ideas. This may lead to violent behavior and, sometimes, hospitalization in an inpatient psychiatric hospital. The severity of manic symptoms can be measured by rating scales such as the Young Mania Rating Scale, though questions remain about the reliability of these scales.

The onset of a manic or depressive episode is often foreshadowed by sleep disturbances. Mood changes, psychomotor and appetite changes, and an increase in anxiety can also occur up to three weeks before a manic episode develops.

Cyclothymia is characterized by short cycles of baseline, stable periods of not over two months and numerous swings between depression and hypomania that fail to meet the severity of sustained duration criterion for major affective syndromes for at least two years.

Depressive/dysthymic episodes. Symptoms of the "depressive/dysthymic phase" may include any of the following conditions:difficulty making decisions, problems concentrating, poor memory recall, guilt, self-criticism, low self-esteem, pessimism, self-destructive thinking, constant sadness, apathy, hopelessness, helplessness and irritability. Also common are quick temper, poor judgment, lack of motivation, social withdrawal, appetite change, lack of sexual desire, self-neglect, fatigue, insomnia and sleepiness.

Hypomanic episodes. Symptoms of the "hypomanic episode" may include any of the following conditions: unusually good mood or cheerfulness (euphoria), extreme optimism, inflated self-esteem, rapid speech, racing thoughts, aggressive or hostile behavior, lack of consideration for others, agitation, massively increased physical activity, risky behavior, spending sprees, increased drive to perform or achieve goals, increased sexual drive, decreased need for sleep, tendency to be easily distracted, and inability to concentrate.

The essential feature of bipolar I disorder is a clinical course characterized by the occurrence of one or more manic episodes or mixed episodes (DSM-IV-TR, 2000). Often, individuals have had one or more major depressive episodes. One episode of mania is sufficient to make the diagnosis of bipolar disorder; the patient may or may not have history of major depressive disorder. Episodes of substance-induced mood disorder due to the direct effects of a medication, or other somatic treatments for depression, drug abuse, or toxin exposure, or of mood disorder due to a general medical condition need to be excluded before a diagnosis of bipolar I disorder can be made. In addition, the episodes must not be better accounted for by schizoaffective disorder or superimposed on schizophrenia, schizophreniform disorder, delusional disorder, or a psychotic disorder not otherwise specified.

Symptoms of the depressive phase of bipolar disorder include persistent feelings of sadness, irritability or anger, loss of interest in previously enjoyed activities, excessive or inappropriate guilt, hopelessness, sleeping too much or not enough, changes in appetite and/or weight, fatigue, problems concentrating, self-loathing or feelings of worthlessness, and thoughts of death or suicide. In severe cases, the individual may develop symptoms of psychosis, a condition also known as severe bipolar disorder with psychotic features. These symptoms include delusions and hallucinations. A major depressive episode persists for at least two weeks, and may result in suicide if left untreated.

The earlier the age of onset, the more likely the first few episodes are to be depressive. Since a diagnosis of bipolar disorder requires a manic or hypomanic episode, many affected individuals are initially misdiagnosed as having major depression and then incorrectly treated with prescribed antidepressants.

SAD is a type of major depressive disorder, and sufferers may exhibit any of the associated symptoms, such as feelings of hopelessness and worthlessness, thoughts of suicide, loss of interest in activities, withdrawal from social interaction, sleep and appetite problems, difficulty with concentrating and making decisions, decreased sex drive, a lack of energy, or agitation. Symptoms of winter SAD often include oversleeping or difficulty waking up in the morning, nausea, and a tendency to over eat, often with a craving for carbohydrates, which leads to weight gain. SAD is typically associated with winter depression, but springtime lethargy or other seasonal mood patterns are not uncommon. Although each individual case is different, in contrast to winter SAD, people who experience spring and summer depression may be more likely to show symptoms such as insomnia, decreased appetite and weight loss, and agitation or anxiety.

There are three different ways to diagnose Bhaskar–Jagannathan. This disorder may be diagnosed by a urine test, a blood test, and an X-ray of the eyes or other body parts.

Individuals with schizophrenia may experience hallucinations (most reported are hearing voices), delusions (often bizarre or persecutory in nature), and disorganized thinking and speech. The last may range from loss of train of thought, to sentences only loosely connected in meaning, to speech that is not understandable known as word salad. Social withdrawal, sloppiness of dress and hygiene, and loss of motivation and judgment are all common in schizophrenia.

Distortions of self-experience such as feeling as if one's thoughts or feelings are not really one's own to believing thoughts are being inserted into one's mind, sometimes termed passivity phenomena, are also common. There is often an observable pattern of emotional difficulty, for example lack of responsiveness. Impairment in social cognition is associated with schizophrenia, as are symptoms of paranoia. Social isolation commonly occurs. Difficulties in working and long-term memory, attention, executive functioning, and speed of processing also commonly occur. In one uncommon subtype, the person may be largely mute, remain motionless in bizarre postures, or exhibit purposeless agitation, all signs of catatonia. People with schizophrenia often find facial emotion perception to be difficult. It is unclear if the phenomenon called "thought blocking", where a talking person suddenly becomes silent for a few seconds to minutes, occurs in schizophrenia.

About 30 to 50 percent of people with schizophrenia fail to accept that they have an illness or comply with their recommended treatment. Treatment may have some effect on insight.

People with schizophrenia may have a high rate of irritable bowel syndrome but they often do not mention it unless specifically asked. Psychogenic polydipsia, or excessive fluid intake in the absence of physiological reasons to drink, is relatively common in people with schizophrenia.

Schizoaffective disorder is defined by "mood disorder-free psychosis" in the context of a long-term psychotic and mood disorder. Psychosis must meet criterion A for schizophrenia which may include delusions, hallucinations, disorganized speech, thinking or behavior and negative symptoms. Both delusions and hallucinations are classic symptoms of psychosis. Delusions are false beliefs which are strongly held despite evidence to the contrary. Beliefs should not be considered delusional if they are in keeping with cultural beliefs. Delusional beliefs may or may not reflect mood symptoms (for example, someone experiencing depression may or may not experience delusions of guilt). Hallucinations are disturbances in perception involving any of the five senses, although auditory hallucinations (or "hearing voices") are the most common. A lack of responsiveness or negative symptoms include alogia (lack of spontaneous speech), blunted affect (reduced intensity of outward emotional expression), avolition (loss of motivation), and anhedonia (inability to experience pleasure). Negative symptoms can be more lasting and more debilitating than positive symptoms of psychosis.

Mood symptoms are of mania, hypomania, mixed episode, or depression, and tend to be episodic rather than continuous. A mixed episode represents a combination of symptoms of mania and depression at the same time. Symptoms of mania include elevated or irritable mood, grandiosity (inflated self-esteem), agitation, risk-taking behavior, decreased need for sleep, poor concentration, rapid speech, and racing thoughts. Symptoms of depression include low mood, apathy, changes in appetite or weight, disturbances in sleep, changes in motor activity, fatigue, guilt or feelings of worthlessness, and suicidal thinking.