Evidence-Based Supplement & Herb Guides

Stereotypic Movement Disorder Causes, Risk Factors, and Associated Conditions

Stereotypic movement disorder involves repetitive, patterned movements that begin early in development and may interfere with daily life or cause injury. Learn key symptoms, causes, risk factors, diagnostic distinctions, and warning signs.

Stereotypic movement disorder is a neurodevelopmental condition involving repetitive, patterned, apparently purposeless movements that begin early in development and are significant enough to interfere...

Speech sound disorder explained: symptoms, causes, and effects

Clear, practical guide to speech sound disorder, including symptoms, sound error patterns, causes, risk factors, diagnostic context, co-occurring concerns, and possible effects on learning and social confidence.

Speech sound disorder is a communication disorder in which a child has persistent difficulty producing speech sounds clearly enough for their age, language background,...

Social withdrawal syndrome: Overview, Symptoms, Causes, and Complications

Social withdrawal syndrome can reflect anxiety, depression, trauma, psychosis, neurodevelopmental differences, or severe prolonged isolation. Learn the signs, risk factors, complications, and when urgent evaluation may be needed.

Social withdrawal syndrome describes a persistent pattern of pulling away from social contact, school, work, family life, or community participation to a degree that...

Social communication disorder: Symptoms, signs, causes, and effects

Learn what social communication disorder means, how symptoms appear across ages, what causes and risk factors are known, how diagnosis is considered, and how it differs from autism.

Social communication disorder is a neurodevelopmental communication condition that affects how a person uses language in social situations. The main difficulty is not simply...

Social anxiety disorder: Signs in Adults, Children, and Teens

Clear overview of social anxiety disorder, including common symptoms, early signs, causes, risk factors, diagnostic context, overlapping conditions, and possible complications.

Social anxiety disorder is more than feeling nervous before a presentation or preferring small gatherings over large crowds. It is a mental health condition...

Sleepwalking disorder in Children and Adults: Symptoms, Causes, and Risks

Learn what sleepwalking disorder means, how symptoms appear, why episodes happen, which risk factors matter, and when dangerous or adult-onset sleepwalking needs evaluation.

Sleepwalking disorder is a sleep-wake condition in which a person partly awakens from deep non-REM sleep and moves, walks, talks, or carries out other...

Sleep terror disorder: Signs, Triggers, Complications, and Key Differences From Nightmares

Sleep terror disorder causes sudden episodes of intense fear during deep sleep. Learn the key symptoms, signs, causes, risk factors, complications, and diagnostic clues that distinguish sleep terrors from nightmares, panic attacks, seizures, and other sleep disorders.

Sleep terror disorder is a sleep-wake condition in which a person has repeated episodes of intense fear during sleep, usually without becoming fully awake....

Shared Psychotic Disorder Symptoms, Signs, Causes, and Risk Factors

Shared psychotic disorder is a rare condition in which delusional beliefs become shared within a close relationship. Learn the key symptoms, risk factors, diagnostic context, and complications that may require urgent evaluation.

Shared psychotic disorder is a rare psychiatric condition in which a delusional belief is shared by two or more people who have a close...

Shared Delusional Disorder Overview and Diagnostic Context

Learn what shared delusional disorder means, how shared psychotic beliefs can develop, which symptoms and risk factors matter, and when urgent evaluation may be needed.

Shared delusional disorder is a rare psychiatric condition in which one person adopts a delusional belief held by another person with whom they have...

Sexual Sadism Disorder Overview, Risk Factors, and Co-Occurring Conditions

Learn what sexual sadism disorder means, how symptoms and warning signs are recognized, how consent affects diagnosis, and what causes, risk factors, and complications may be involved.

Sexual sadism disorder is a psychiatric diagnosis involving recurrent, intense sexual arousal from the physical or psychological suffering of another person, when those urges,...

Sexual aversion disorder Causes, Triggers, and Risk Factors

Learn what sexual aversion disorder means, how symptoms may appear, why it can develop, which risk factors matter, and how it differs from low desire, asexuality, trauma responses, and sexual pain.

Sexual aversion disorder is a pattern of strong fear, disgust, anxiety, or avoidance related to sexual contact. The term has a complicated diagnostic history:...

Severe Mental Illness Symptoms, Signs, Risk Factors, and Effects

Learn what severe mental illness means, which conditions are often included, how symptoms and warning signs appear, and why causes, risk factors, complications, and diagnostic context matter.

Severe mental illness is not one single diagnosis. It is a practical term used for mental health conditions that cause major disruption in a...

Separation Anxiety Disorder Causes, Risk Factors, and Co-Occurring Conditions

Learn what separation anxiety disorder is, how symptoms appear in children, teens, and adults, what may contribute to it, and when professional evaluation matters.

Separation anxiety disorder is more than ordinary missing, clinginess, or worry when someone important leaves. It is a mental health condition in which separation...

Sensory processing disorder symptoms, signs, causes, and complications

Learn what sensory processing disorder means, how symptoms can appear across senses and ages, what conditions may overlap with it, and when sensory changes need professional evaluation.

Sensory processing disorder is a term used to describe ongoing difficulty noticing, organizing, interpreting, or responding to sensory information. The information may come from...

Self-identity disorder: Signs, Risk Factors, and Related Conditions

Self-identity disorder can describe distressing disruption in identity, memory, agency, or sense of self. Learn how symptoms may appear, what conditions can overlap, and when urgent evaluation matters.

Self-identity disorder is not usually used as a single formal diagnosis in major psychiatric classification systems. In everyday language, however, it often describes a...

Selective Mutism Signs and Symptoms Across Settings and Ages

Selective mutism is an anxiety-related condition where speech is possible in some settings but blocked in others. Learn the key symptoms, signs, causes, risk factors, diagnostic context, and possible complications.

Selective mutism is an anxiety-related condition in which a person is able to speak in some situations but consistently cannot speak in others where...

Seasonal Affective Disorder (SAD): Overview, Symptoms, Causes, and Complications

Clear overview of seasonal affective disorder, including winter and summer patterns, symptoms, diagnostic context, likely causes, risk factors, and complications that may require urgent evaluation.

Seasonal affective disorder (SAD) is a recurring pattern of depression linked to changes in season. It most often appears in late fall or winter...

Schizotypal Personality Disorder Signs, Causes, and Related Conditions

Schizotypal personality disorder involves long-standing social discomfort, unusual beliefs, suspiciousness, eccentric behavior, and perceptual distortions. Learn the key signs, risk factors, diagnostic context, similar conditions, and complications that may require urgent evaluation.

Schizotypal personality disorder is a mental health condition marked by long-standing patterns of social discomfort, unusual thinking or perception, eccentric behavior, and difficulty forming...

Schizophrenia in Adults: Overview, Symptoms, Course, and Risk Factors

Schizophrenia is a complex psychotic disorder involving hallucinations, delusions, negative symptoms, cognitive changes, and functional impairment. Learn how symptoms, causes, risk factors, diagnostic context, and complications are understood.

Schizophrenia is a serious psychiatric condition that affects how a person experiences reality, organizes thoughts, expresses emotion, and functions in daily life. It is...

Schizoid personality disorder Overview, Symptoms, and Safety Concerns

A clear guide to schizoid personality disorder, including its main symptoms, signs, causes, risk factors, diagnostic context, related conditions, and possible complications.

Schizoid personality disorder is a long-term pattern of social detachment, limited emotional expression, and low interest in close relationships. A person with this condition...