Bipolar Disorder: A major affective disorder marked by severe mood swings (manic or major depressive episodes) and a tendency to remission and recurrence.Mental Disorders: Psychiatric illness or diseases manifested by breakdowns in the adaptational process expressed primarily as abnormalities of thought, feeling, and behavior producing either distress or impairment of function.Anxiety Disorders: Persistent and disabling ANXIETY.Mood Disorders: Those disorders that have a disturbance in mood as their predominant feature.Diagnostic and Statistical Manual of Mental Disorders: Categorical classification of MENTAL DISORDERS based on criteria sets with defining features. It is produced by the American Psychiatric Association. (DSM-IV, page xxii)Depressive Disorder, Major: Marked depression appearing in the involution period and characterized by hallucinations, delusions, paranoia, and agitation.Attention Deficit Disorder with Hyperactivity: A behavior disorder originating in childhood in which the essential features are signs of developmentally inappropriate inattention, impulsivity, and hyperactivity. Although most individuals have symptoms of both inattention and hyperactivity-impulsivity, one or the other pattern may be predominant. The disorder is more frequent in males than females. Onset is in childhood. Symptoms often attenuate during late adolescence although a minority experience the full complement of symptoms into mid-adulthood. (From DSM-V)Depressive Disorder: An affective disorder manifested by either a dysphoric mood or loss of interest or pleasure in usual activities. The mood disturbance is prominent and relatively persistent.Obsessive-Compulsive Disorder: An anxiety disorder characterized by recurrent, persistent obsessions or compulsions. Obsessions are the intrusive ideas, thoughts, or images that are experienced as senseless or repugnant. Compulsions are repetitive and seemingly purposeful behavior which the individual generally recognizes as senseless and from which the individual does not derive pleasure although it may provide a release from tension.Stress Disorders, Post-Traumatic: A class of traumatic stress disorders with symptoms that last more than one month. There are various forms of post-traumatic stress disorder, depending on the time of onset and the duration of these stress symptoms. In the acute form, the duration of the symptoms is between 1 to 3 months. In the chronic form, symptoms last more than 3 months. With delayed onset, symptoms develop more than 6 months after the traumatic event.Autistic Disorder: A disorder beginning in childhood. It is marked by the presence of markedly abnormal or impaired development in social interaction and communication and a markedly restricted repertoire of activity and interest. Manifestations of the disorder vary greatly depending on the developmental level and chronological age of the individual. (DSM-V)Phobic Disorders: Anxiety disorders in which the essential feature is persistent and irrational fear of a specific object, activity, or situation that the individual feels compelled to avoid. The individual recognizes the fear as excessive or unreasonable.Child Development Disorders, Pervasive: Severe distortions in the development of many basic psychological functions that are not normal for any stage in development. These distortions are manifested in sustained social impairment, speech abnormalities, and peculiar motor movements.Psychotic Disorders: Disorders in which there is a loss of ego boundaries or a gross impairment in reality testing with delusions or prominent hallucinations. (From DSM-IV, 1994)Substance-Related Disorders: Disorders related to substance abuse.Conduct Disorder: A repetitive and persistent pattern of behavior in which the basic rights of others or major age-appropriate societal norms or rules are violated. These behaviors include aggressive conduct that causes or threatens physical harm to other people or animals, nonaggressive conduct that causes property loss or damage, deceitfulness or theft, and serious violations of rules. The onset is before age 18. (From DSM-IV, 1994)Tic Disorders: Disorders characterized by recurrent TICS that may interfere with speech and other activities. Tics are sudden, rapid, nonrhythmic, stereotyped motor movements or vocalizations which may be exacerbated by stress and are generally attenuated during absorbing activities. Tic disorders are distinguished from conditions which feature other types of abnormal movements that may accompany another another condition. (From DSM-IV, 1994)Psychiatric Status Rating Scales: Standardized procedures utilizing rating scales or interview schedules carried out by health personnel for evaluating the degree of mental illness.Borderline Personality Disorder: A personality disorder marked by a pattern of instability of interpersonal relationships, self-image, and affects, and marked impulsivity beginning by early adulthood and present in a variety of contexts. (DSM-IV)Somatoform Disorders: Disorders having the presence of physical symptoms that suggest a general medical condition but that are not fully explained by a another medical condition, by the direct effects of a substance, or by another mental disorder. The symptoms must cause clinically significant distress or impairment in social, occupational, or other areas of functioning. In contrast to FACTITIOUS DISORDERS and MALINGERING, the physical symptoms are not under voluntary control. (APA, DSM-V)Cognition Disorders: Disturbances in mental processes related to learning, thinking, reasoning, and judgment.Sleep Disorders: Conditions characterized by disturbances of usual sleep patterns or behaviors. Sleep disorders may be divided into three major categories: DYSSOMNIAS (i.e. disorders characterized by insomnia or hypersomnia), PARASOMNIAS (abnormal sleep behaviors), and sleep disorders secondary to medical or psychiatric disorders. (From Thorpy, Sleep Disorders Medicine, 1994, p187)Lymphoproliferative Disorders: Disorders characterized by proliferation of lymphoid tissue, general or unspecified.Comorbidity: The presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.Alcohol-Related Disorders: Disorders related to or resulting from abuse or mis-use of alcohol.Movement Disorders: Syndromes which feature DYSKINESIAS as a cardinal manifestation of the disease process. Included in this category are degenerative, hereditary, post-infectious, medication-induced, post-inflammatory, and post-traumatic conditions.Speech Disorders: Acquired or developmental conditions marked by an impaired ability to comprehend or generate spoken forms of language.Combat Disorders: Neurotic reactions to unusual, severe, or overwhelming military stress.Attention Deficit and Disruptive Behavior Disorders: Includes two similar disorders: oppositional defiant disorder and CONDUCT DISORDERS. Symptoms occurring in children with these disorders include: defiance of authority figures, angry outbursts, and other antisocial behaviors.Impulse Control Disorders: Disorders whose essential features are the failure to resist an impulse, drive, or temptation to perform an act that is harmful to the individual or to others. Individuals experience an increased sense of tension prior to the act and pleasure, gratification or release of tension at the time of committing the act.Schizophrenia: A severe emotional disorder of psychotic depth characteristically marked by a retreat from reality with delusion formation, HALLUCINATIONS, emotional disharmony, and regressive behavior.Antisocial Personality Disorder: A personality disorder whose essential feature is a pervasive pattern of disregard for, and violation of, the rights of others that begins in childhood or early adolescence and continues into adulthood. The individual must be at least age 18 and must have a history of some symptoms of CONDUCT DISORDER before age 15. (From DSM-IV, 1994)Binge-Eating Disorder: A disorder associated with three or more of the following: eating until feeling uncomfortably full; eating large amounts of food when not physically hungry; eating much more rapidly than normal; eating alone due to embarrassment; feeling of disgust, DEPRESSION, or guilt after overeating. Criteria includes occurrence on average, at least 2 days a week for 6 months. The binge eating is not associated with the regular use of inappropriate compensatory behavior (i.e. purging, excessive exercise, etc.) and does not co-occur exclusively with BULIMIA NERVOSA or ANOREXIA NERVOSA. (From DSM-IV, 1994)Dysthymic Disorder: Chronically depressed mood that occurs for most of the day more days than not for at least 2 years. The required minimum duration in children to make this diagnosis is 1 year. During periods of depressed mood, at least 2 of the following additional symptoms are present: poor appetite or overeating, insomnia or hypersomnia, low energy or fatigue, low self esteem, poor concentration or difficulty making decisions, and feelings of hopelessness. (DSM-IV)Myeloproliferative Disorders: Conditions which cause proliferation of hemopoietically active tissue or of tissue which has embryonic hemopoietic potential. They all involve dysregulation of multipotent MYELOID PROGENITOR CELLS, most often caused by a mutation in the JAK2 PROTEIN TYROSINE KINASE.Interview, Psychological: A directed conversation aimed at eliciting information for psychiatric diagnosis, evaluation, treatment planning, etc. The interview may be conducted by a social worker or psychologist.Dissociative Disorders: Sudden temporary alterations in the normally integrative functions of consciousness.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.Temporomandibular Joint Disorders: A variety of conditions affecting the anatomic and functional characteristics of the temporomandibular joint. Factors contributing to the complexity of temporomandibular diseases are its relation to dentition and mastication and the symptomatic effects in other areas which account for referred pain to the joint and the difficulties in applying traditional diagnostic procedures to temporomandibular joint pathology where tissue is rarely obtained and x-rays are often inadequate or nonspecific. Common diseases are developmental abnormalities, trauma, subluxation, luxation, arthritis, and neoplasia. (From Thoma's Oral Pathology, 6th ed, pp577-600)Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Conversion Disorder: A disorder whose predominant feature is a loss or alteration in physical functioning that suggests a physical disorder but that is actually a direct expression of a psychological conflict or need.Learning Disorders: Conditions characterized by a significant discrepancy between an individual's perceived level of intellect and their ability to acquire new language and other cognitive skills. These disorders may result from organic or psychological conditions. Relatively common subtypes include DYSLEXIA, DYSCALCULIA, and DYSGRAPHIA.Schizotypal Personality Disorder: A personality disorder in which there are oddities of thought (magical thinking, paranoid ideation, suspiciousness), perception (illusions, depersonalization), speech (digressive, vague, overelaborate), and behavior (inappropriate affect in social interactions, frequently social isolation) that are not severe enough to characterize schizophrenia.Severity of Illness Index: Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.Neurotic Disorders: Disorders in which the symptoms are distressing to the individual and recognized by him or her as being unacceptable. Social relationships may be greatly affected but usually remain within acceptable limits. The disturbance is relatively enduring or recurrent without treatment.Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.Antimanic Agents: Agents that are used to treat bipolar disorders or mania associated with other affective disorders.Nervous System Diseases: Diseases of the central and peripheral nervous system. This includes disorders of the brain, spinal cord, cranial nerves, peripheral nerves, nerve roots, autonomic nervous system, neuromuscular junction, and muscle.Syndrome: A characteristic symptom complex.Affective Disorders, Psychotic: Disorders in which the essential feature is a severe disturbance in mood (depression, anxiety, elation, and excitement) accompanied by psychotic symptoms such as delusions, hallucinations, gross impairment in reality testing, etc.Pedigree: The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.Case-Control Studies: Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Alcoholism: A primary, chronic disease with genetic, psychosocial, and environmental factors influencing its development and manifestations. The disease is often progressive and fatal. It is characterized by impaired control over drinking, preoccupation with the drug alcohol, use of alcohol despite adverse consequences, and distortions in thinking, most notably denial. Each of these symptoms may be continuous or periodic. (Morse & Flavin for the Joint Commission of the National Council on Alcoholism and Drug Dependence and the American Society of Addiction Medicine to Study the Definition and Criteria for the Diagnosis of Alcoholism: in JAMA 1992;268:1012-4)Diagnosis, Dual (Psychiatry): The co-existence of a substance abuse disorder with a psychiatric disorder. The diagnostic principle is based on the fact that it has been found often that chemically dependent patients also have psychiatric problems of various degrees of severity.Personality Assessment: The determination and evaluation of personality attributes by interviews, observations, tests, or scales. Articles concerning personality measurement are considered to be within scope of this term.Adjustment Disorders: Maladaptive reactions to identifiable psychosocial stressors occurring within a short time after onset of the stressor. They are manifested by either impairment in social or occupational functioning or by symptoms (depression, anxiety, etc.) that are in excess of a normal and expected reaction to the stressor.Peroxisomal Disorders: A heterogeneous group of inherited metabolic disorders marked by absent or dysfunctional PEROXISOMES. Peroxisomal enzymatic abnormalities may be single or multiple. Biosynthetic peroxisomal pathways are compromised, including the ability to synthesize ether lipids and to oxidize long-chain fatty acid precursors. Diseases in this category include ZELLWEGER SYNDROME; INFANTILE REFSUM DISEASE; rhizomelic chondrodysplasia (CHONDRODYSPLASIA PUNCTATA, RHIZOMELIC); hyperpipecolic acidemia; neonatal adrenoleukodystrophy; and ADRENOLEUKODYSTROPHY (X-linked). Neurologic dysfunction is a prominent feature of most peroxisomal disorders.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Language Disorders: Conditions characterized by deficiencies of comprehension or expression of written and spoken forms of language. These include acquired and developmental disorders.Bulimia Nervosa: An eating disorder that is characterized by a cycle of binge eating (BULIMIA or bingeing) followed by inappropriate acts (purging) to avert weight gain. Purging methods often include self-induced VOMITING, use of LAXATIVES or DIURETICS, excessive exercise, and FASTING.Body Dysmorphic Disorders: Preoccupations with appearance or self-image causing significant distress or impairment in important areas of functioning.Age of Onset: The age, developmental stage, or period of life at which a disease or the initial symptoms or manifestations of a disease appear in an individual.Anxiety: Feeling or emotion of dread, apprehension, and impending disaster but not disabling as with ANXIETY DISORDERS.Fetal Alcohol Spectrum Disorders: An umbrella term used to describe a pattern of disabilities and abnormalities that result from fetal exposure to ETHANOL during pregnancy. It encompasses a phenotypic range that can vary greatly between individuals, but reliably includes one or more of the following: characteristic facial dysmorphism, FETAL GROWTH RETARDATION, central nervous system abnormalities, cognitive and/or behavioral dysfunction, BIRTH DEFECTS. The level of maternal alcohol consumption does not necessarily correlate directly with disease severity.Cognitive Therapy: A direct form of psychotherapy based on the interpretation of situations (cognitive structure of experiences) that determine how an individual feels and behaves. It is based on the premise that cognition, the process of acquiring knowledge and forming beliefs, is a primary determinant of mood and behavior. The therapy uses behavioral and verbal techniques to identify and correct negative thinking that is at the root of the aberrant behavior.Child Behavior Disorders: Disturbances considered to be pathological based on age and stage appropriateness, e.g., conduct disturbances and anaclitic depression. This concept does not include psychoneuroses, psychoses, or personality disorders with fixed patterns.Congenital Disorders of Glycosylation: A genetically heterogeneous group of heritable disorders resulting from defects in protein N-glycosylation.Neuropsychological Tests: Tests designed to assess neurological function associated with certain behaviors. They are used in diagnosing brain dysfunction or damage and central nervous system disorders or injury.Psychophysiologic Disorders: A group of disorders characterized by physical symptoms that are affected by emotional factors and involve a single organ system, usually under AUTONOMIC NERVOUS SYSTEM control. (American Psychiatric Glossary, 1988)Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Antidepressive Agents: Mood-stimulating drugs used primarily in the treatment of affective disorders and related conditions. Several MONOAMINE OXIDASE INHIBITORS are useful as antidepressants apparently as a long-term consequence of their modulation of catecholamine levels. The tricyclic compounds useful as antidepressive agents (ANTIDEPRESSIVE AGENTS, TRICYCLIC) also appear to act through brain catecholamine systems. A third group (ANTIDEPRESSIVE AGENTS, SECOND-GENERATION) is a diverse group of drugs including some that act specifically on serotonergic systems.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Genetic Predisposition to Disease: A latent susceptibility to disease at the genetic level, which may be activated under certain conditions.Agoraphobia: Obsessive, persistent, intense fear of open places.Depression: Depressive states usually of moderate intensity in contrast with major depression present in neurotic and psychotic disorders.Factitious Disorders: Disorders characterized by physical or psychological symptoms that are not real, genuine, or natural.Psychometrics: Assessment of psychological variables by the application of mathematical procedures.Language Development Disorders: Conditions characterized by language abilities (comprehension and expression of speech and writing) that are below the expected level for a given age, generally in the absence of an intellectual impairment. These conditions may be associated with DEAFNESS; BRAIN DISEASES; MENTAL DISORDERS; or environmental factors.Memory Disorders: Disturbances in registering an impression, in the retention of an acquired impression, or in the recall of an impression. Memory impairments are associated with DEMENTIA; CRANIOCEREBRAL TRAUMA; ENCEPHALITIS; ALCOHOLISM (see also ALCOHOL AMNESTIC DISORDER); SCHIZOPHRENIA; and other conditions.Hemorrhagic Disorders: Spontaneous or near spontaneous bleeding caused by a defect in clotting mechanisms (BLOOD COAGULATION DISORDERS) or another abnormality causing a structural flaw in the blood vessels (HEMOSTATIC DISORDERS).Blood Platelet Disorders: Disorders caused by abnormalities in platelet count or function.Cross-Sectional Studies: Studies in which the presence or absence of disease or other health-related variables are determined in each member of the study population or in a representative sample at one particular time. This contrasts with LONGITUDINAL STUDIES which are followed over a period of time.Psychotherapy: A generic term for the treatment of mental illness or emotional disturbances primarily by verbal or nonverbal communication.Musculoskeletal Diseases: Diseases of the muscles and their associated ligaments and other connective tissue and of the bones and cartilage viewed collectively.Cumulative Trauma Disorders: Harmful and painful condition caused by overuse or overexertion of some part of the musculoskeletal system, often resulting from work-related physical activities. It is characterized by inflammation, pain, or dysfunction of the involved joints, bones, ligaments, and nerves.Personality Inventory: Check list, usually to be filled out by a person about himself, consisting of many statements about personal characteristics which the subject checks.Sleep Initiation and Maintenance Disorders: Disorders characterized by impairment of the ability to initiate or maintain sleep. This may occur as a primary disorder or in association with another medical or psychiatric condition.Voice Disorders: Pathological processes that affect voice production, usually involving VOCAL CORDS and the LARYNGEAL MUCOSA. Voice disorders can be caused by organic (anatomical), or functional (emotional or psychological) factors leading to DYSPHONIA; APHONIA; and defects in VOICE QUALITY, loudness, and pitch.Asperger Syndrome: A disorder beginning in childhood whose essential features are persistent impairment in reciprocal social communication and social interaction, and restricted, repetitive patterns of behavior, interests, or activities. These symptoms may limit or impair everyday functioning. (From DSM-5)Psychotropic Drugs: A loosely defined grouping of drugs that have effects on psychological function. Here the psychotropic agents include the antidepressive agents, hallucinogens, and tranquilizing agents (including the antipsychotics and anti-anxiety agents).Motor Skills Disorders: Marked impairments in the development of motor coordination such that the impairment interferes with activities of daily living. (From DSM-V)Communication Disorders: Disorders of verbal and nonverbal communication caused by receptive or expressive LANGUAGE DISORDERS, cognitive dysfunction (e.g., MENTAL RETARDATION), psychiatric conditions, and HEARING DISORDERS.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Cyclothymic Disorder: An affective disorder characterized by periods of depression and hypomania. These may be separated by periods of normal mood.Compulsive Personality Disorder: Disorder characterized by an emotionally constricted manner that is unduly conventional, serious, formal, and stingy, by preoccupation with trivial details, rules, order, organization, schedules, and lists, by stubborn insistence on having things one's own way without regard for the effects on others, by poor interpersonal relationships, and by indecisiveness due to fear of making mistakes.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Antipsychotic Agents: Agents that control agitated psychotic behavior, alleviate acute psychotic states, reduce psychotic symptoms, and exert a quieting effect. They are used in SCHIZOPHRENIA; senile dementia; transient psychosis following surgery; or MYOCARDIAL INFARCTION; etc. These drugs are often referred to as neuroleptics alluding to the tendency to produce neurological side effects, but not all antipsychotics are likely to produce such effects. Many of these drugs may also be effective against nausea, emesis, and pruritus.Alcohol-Induced Disorders: Disorders stemming from the misuse and abuse of alcohol.Sex Factors: Maleness or femaleness as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or effect of a circumstance. It is used with human or animal concepts but should be differentiated from SEX CHARACTERISTICS, anatomical or physiological manifestations of sex, and from SEX DISTRIBUTION, the number of males and females in given circumstances.Neurodegenerative Diseases: Hereditary and sporadic conditions which are characterized by progressive nervous system dysfunction. These disorders are often associated with atrophy of the affected central or peripheral nervous system structures.Psychomotor Disorders: Abnormalities of motor function that are associated with organic and non-organic cognitive disorders.Migraine Disorders: A class of disabling primary headache disorders, characterized by recurrent unilateral pulsatile headaches. The two major subtypes are common migraine (without aura) and classic migraine (with aura or neurological symptoms). (International Classification of Headache Disorders, 2nd ed. Cephalalgia 2004: suppl 1)United StatesLongitudinal Studies: Studies in which variables relating to an individual or group of individuals are assessed over a period of time.Age Factors: Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.Metabolism, Inborn Errors: Errors in metabolic processes resulting from inborn genetic mutations that are inherited or acquired in utero.Delirium, Dementia, Amnestic, Cognitive Disorders: Cognitive disorders including delirium, dementia, and other cognitive disorders. These may be the result of substance use, trauma, or other causes.Anorexia Nervosa: An eating disorder that is characterized by the lack or loss of APPETITE, known as ANOREXIA. Other features include excess fear of becoming OVERWEIGHT; BODY IMAGE disturbance; significant WEIGHT LOSS; refusal to maintain minimal normal weight; and AMENORRHEA. This disorder occurs most frequently in adolescent females. (APA, Thesaurus of Psychological Index Terms, 1994)Stress Disorders, Traumatic, Acute: A class of traumatic stress disorders that is characterized by the significant dissociative states seen immediately after overwhelming trauma. By definition it cannot last longer than 1 month, if it persists, a diagnosis of post-traumatic stress disorder (STRESS DISORDERS, POST-TRAUMATIC) is more appropriate.Metabolic Diseases: Generic term for diseases caused by an abnormal metabolic process. It can be congenital due to inherited enzyme abnormality (METABOLISM, INBORN ERRORS) or acquired due to disease of an endocrine organ or failure of a metabolically important organ such as the liver. (Stedman, 26th ed)Schizophrenic Psychology: Study of mental processes and behavior of schizophrenics.Sleep Disorders, Circadian Rhythm: Dyssomnias associated with disruption of the normal 24 hour sleep wake cycle secondary to travel (e.g., JET LAG SYNDROME), shift work, or other causes.Follow-Up Studies: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.Health Surveys: A systematic collection of factual data pertaining to health and disease in a human population within a given geographic area.REM Sleep Behavior Disorder: A disorder characterized by episodes of vigorous and often violent motor activity during REM sleep (SLEEP, REM). The affected individual may inflict self injury or harm others, and is difficult to awaken from this condition. Episodes are usually followed by a vivid recollection of a dream that is consistent with the aggressive behavior. This condition primarily affects adult males. (From Adams et al., Principles of Neurology, 6th ed, p393)Stress, Psychological: Stress wherein emotional factors predominate.Social Behavior Disorders: Behaviors which are at variance with the expected social norm and which affect other individuals.Lithium Compounds: Inorganic compounds that contain lithium as an integral part of the molecule.Suicide, Attempted: The unsuccessful attempt to kill oneself.Auditory Perceptual Disorders: Acquired or developmental cognitive disorders of AUDITORY PERCEPTION characterized by a reduced ability to perceive information contained in auditory stimuli despite intact auditory pathways. Affected individuals have difficulty with speech perception, sound localization, and comprehending the meaning of inflections of speech.Child of Impaired Parents: Child with one or more parents afflicted by a physical or mental disorder.Life Change Events: Those occurrences, including social, psychological, and environmental, which require an adjustment or effect a change in an individual's pattern of living.Taste Disorders: Conditions characterized by an alteration in gustatory function or perception. Taste disorders are frequently associated with OLFACTION DISORDERS. Additional potential etiologies include METABOLIC DISEASES; DRUG TOXICITY; and taste pathway disorders (e.g., TASTE BUD diseases; FACIAL NERVE DISEASES; GLOSSOPHARYNGEAL NERVE DISEASES; and BRAIN STEM diseases).Psychopathology: The study of significant causes and processes in the development of mental illness.Blood Coagulation Disorders: Hemorrhagic and thrombotic disorders that occur as a consequence of abnormalities in blood coagulation due to a variety of factors such as COAGULATION PROTEIN DISORDERS; BLOOD PLATELET DISORDERS; BLOOD PROTEIN DISORDERS or nutritional conditions.Methylphenidate: A central nervous system stimulant used most commonly in the treatment of ATTENTION DEFICIT DISORDER in children and for NARCOLEPSY. Its mechanisms appear to be similar to those of DEXTROAMPHETAMINE. The d-isomer of this drug is referred to as DEXMETHYLPHENIDATE HYDROCHLORIDE.Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Genotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.Parkinsonian Disorders: A group of disorders which feature impaired motor control characterized by bradykinesia, MUSCLE RIGIDITY; TREMOR; and postural instability. Parkinsonian diseases are generally divided into primary parkinsonism (see PARKINSON DISEASE), secondary parkinsonism (see PARKINSON DISEASE, SECONDARY) and inherited forms. These conditions are associated with dysfunction of dopaminergic or closely related motor integration neuronal pathways in the BASAL GANGLIA.Affect: The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves.Impulsive Behavior: An act performed without delay, reflection, voluntary direction or obvious control in response to a stimulus.Bulimia: Eating an excess amount of food in a short period of time, as seen in the disorder of BULIMIA NERVOSA. It is caused by an abnormal craving for food, or insatiable hunger also known as "ox hunger".Chronic Disease: Diseases which have one or more of the following characteristics: they are permanent, leave residual disability, are caused by nonreversible pathological alteration, require special training of the patient for rehabilitation, or may be expected to require a long period of supervision, observation, or care. (Dictionary of Health Services Management, 2d ed)Pigmentation DisordersGenetic Linkage: The co-inheritance of two or more non-allelic GENES due to their being located more or less closely on the same CHROMOSOME.Cohort Studies: Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Serotonin Uptake Inhibitors: Compounds that specifically inhibit the reuptake of serotonin in the brain.Tobacco Use Disorder: Tobacco used to the detriment of a person's health or social functioning. Tobacco dependence is included.Genetic Diseases, Inborn: Diseases that are caused by genetic mutations present during embryo or fetal development, although they may be observed later in life. The mutations may be inherited from a parent's genome or they may be acquired in utero.Central Nervous System Stimulants: A loosely defined group of drugs that tend to increase behavioral alertness, agitation, or excitation. They work by a variety of mechanisms, but usually not by direct excitation of neurons. The many drugs that have such actions as side effects to their main therapeutic use are not included here.Blood Coagulation Disorders, Inherited: Hemorrhagic and thrombotic disorders that occur as a consequence of inherited abnormalities in blood coagulation.Sensation Disorders: Disorders of the special senses (i.e., VISION; HEARING; TASTE; and SMELL) or somatosensory system (i.e., afferent components of the PERIPHERAL NERVOUS SYSTEM).Developmental Disabilities: Disorders in which there is a delay in development based on that expected for a given age level or stage of development. These impairments or disabilities originate before age 18, may be expected to continue indefinitely, and constitute a substantial impairment. Biological and nonbiological factors are involved in these disorders. (From American Psychiatric Glossary, 6th ed)Pelvic Floor Disorders: Injury, weakening, or PROLAPSE of the pelvic muscles, surrounding connective tissues or ligaments (PELVIC FLOOR).Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Emotions: Those affective states which can be experienced and have arousing and motivational properties.Family Health: The health status of the family as a unit including the impact of the health of one member of the family on the family as a unit and on individual family members; also, the impact of family organization or disorganization on the health status of its members.Tourette Syndrome: A neuropsychological disorder related to alterations in DOPAMINE metabolism and neurotransmission involving frontal-subcortical neuronal circuits. Both multiple motor and one or more vocal tics need to be present with TICS occurring many times a day, nearly daily, over a period of more than one year. The onset is before age 18 and the disturbance is not due to direct physiological effects of a substance or a another medical condition. The disturbance causes marked distress or significant impairment in social, occupational, or other important areas of functioning. (From DSM-IV, 1994; Neurol Clin 1997 May;15(2):357-79)Chromosome Disorders: Clinical conditions caused by an abnormal chromosome constitution in which there is extra or missing chromosome material (either a whole chromosome or a chromosome segment). (from Thompson et al., Genetics in Medicine, 5th ed, p429)Mental Health Services: Organized services to provide mental health care.Lipid Metabolism Disorders: Pathological conditions resulting from abnormal anabolism or catabolism of lipids in the body.Gastrointestinal Diseases: Diseases in any segment of the GASTROINTESTINAL TRACT from ESOPHAGUS to RECTUM.Endocrine System Diseases: Pathological processes of the ENDOCRINE GLANDS, and diseases resulting from abnormal level of available HORMONES.Diseases in Twins: Disorders affecting TWINS, one or both, at any age.Mitochondrial Diseases: Diseases caused by abnormal function of the MITOCHONDRIA. They may be caused by mutations, acquired or inherited, in mitochondrial DNA or in nuclear genes that code for mitochondrial components. They may also be the result of acquired mitochondria dysfunction due to adverse effects of drugs, infections, or other environmental causes.Intellectual Disability: Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual has an intellectual disability. IQ scores between 70 and 79 are in the borderline range. Scores below 67 are in the disabled range. (from Joynt, Clinical Neurology, 1992, Ch55, p28)Parkinson Disease: A progressive, degenerative neurologic disease characterized by a TREMOR that is maximal at rest, retropulsion (i.e. a tendency to fall backwards), rigidity, stooped posture, slowness of voluntary movements, and a masklike facial expression. Pathologic features include loss of melanin containing neurons in the substantia nigra and other pigmented nuclei of the brainstem. LEWY BODIES are present in the substantia nigra and locus coeruleus but may also be found in a related condition (LEWY BODY DISEASE, DIFFUSE) characterized by dementia in combination with varying degrees of parkinsonism. (Adams et al., Principles of Neurology, 6th ed, p1059, pp1067-75)Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.Chronobiology Disorders: Disruptions of the rhythmic cycle of bodily functions or activities.Infant, Newborn: An infant during the first month after birth.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Perceptual Disorders: Cognitive disorders characterized by an impaired ability to perceive the nature of objects or concepts through use of the sense organs. These include spatial neglect syndromes, where an individual does not attend to visual, auditory, or sensory stimuli presented from one side of the body.Dystonic Disorders: Acquired and inherited conditions that feature DYSTONIA as a primary manifestation of disease. These disorders are generally divided into generalized dystonias (e.g., dystonia musculorum deformans) and focal dystonias (e.g., writer's cramp). They are also classified by patterns of inheritance and by age of onset.Articulation Disorders: Disorders of the quality of speech characterized by the substitution, omission, distortion, and addition of phonemes.DNA Mutational Analysis: Biochemical identification of mutational changes in a nucleotide sequence.Social Behavior: Any behavior caused by or affecting another individual, usually of the same species.Delusions: A false belief regarding the self or persons or objects outside the self that persists despite the facts, and is not considered tenable by one's associates.Neuromuscular Diseases: A general term encompassing lower MOTOR NEURON DISEASE; PERIPHERAL NERVOUS SYSTEM DISEASES; and certain MUSCULAR DISEASES. Manifestations include MUSCLE WEAKNESS; FASCICULATION; muscle ATROPHY; SPASM; MYOKYMIA; MUSCLE HYPERTONIA, myalgias, and MUSCLE HYPOTONIA.Skin DiseasesNeurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Suicide: The act of killing oneself.Abnormalities, MultipleMutation, Missense: A mutation in which a codon is mutated to one directing the incorporation of a different amino acid. This substitution may result in an inactive or unstable product. (From A Dictionary of Genetics, King & Stansfield, 5th ed)Disorders of Excessive Somnolence: Disorders characterized by hypersomnolence during normal waking hours that may impair cognitive functioning. Subtypes include primary hypersomnia disorders (e.g., IDIOPATHIC HYPERSOMNOLENCE; NARCOLEPSY; and KLEINE-LEVIN SYNDROME) and secondary hypersomnia disorders where excessive somnolence can be attributed to a known cause (e.g., drug affect, MENTAL DISORDERS, and SLEEP APNEA SYNDROME). (From J Neurol Sci 1998 Jan 8;153(2):192-202; Thorpy, Principles and Practice of Sleep Medicine, 2nd ed, p320)Lysosomal Storage Diseases: Inborn errors of metabolism characterized by defects in specific lysosomal hydrolases and resulting in intracellular accumulation of unmetabolized substrates.Veterans: Former members of the armed services.Models, Psychological: Theoretical representations that simulate psychological processes and/or social processes. These include the use of mathematical equations, computers, and other electronic equipment.Genes, Recessive: Genes that influence the PHENOTYPE only in the homozygous state.Logistic Models: Statistical models which describe the relationship between a qualitative dependent variable (that is, one which can take only certain discrete values, such as the presence or absence of a disease) and an independent variable. A common application is in epidemiology for estimating an individual's risk (probability of a disease) as a function of a given risk factor.Prefrontal Cortex: The rostral part of the frontal lobe, bounded by the inferior precentral fissure in humans, which receives projection fibers from the MEDIODORSAL NUCLEUS OF THE THALAMUS. The prefrontal cortex receives afferent fibers from numerous structures of the DIENCEPHALON; MESENCEPHALON; and LIMBIC SYSTEM as well as cortical afferents of visual, auditory, and somatic origin.Body Image: Individuals' concept of their own bodies.Affective Symptoms: Mood or emotional responses dissonant with or inappropriate to the behavior and/or stimulus.46, XY Disorders of Sex Development: Congenital conditions in individuals with a male karyotype, in which the development of the gonadal or anatomical sex is atypical.Personality: Behavior-response patterns that characterize the individual.Nerve Tissue ProteinsCognition: Intellectual or mental process whereby an organism obtains knowledge.Growth Disorders: Deviations from the average values for a specific age and sex in any or all of the following: height, weight, skeletal proportions, osseous development, or maturation of features. Included here are both acceleration and retardation of growth.Lithium Carbonate: A lithium salt, classified as a mood-stabilizing agent. Lithium ion alters the metabolism of BIOGENIC MONOAMINES in the CENTRAL NERVOUS SYSTEM, and affects multiple neurotransmission systems.Consciousness Disorders: Organic mental disorders in which there is impairment of the ability to maintain awareness of self and environment and to respond to environmental stimuli. Dysfunction of the cerebral hemispheres or brain stem RETICULAR FORMATION may result in this condition.Irritable Mood: Abnormal or excessive excitability with easily triggered anger, annoyance, or impatience.Amygdala: Almond-shaped group of basal nuclei anterior to the INFERIOR HORN OF THE LATERAL VENTRICLE of the TEMPORAL LOBE. The amygdala is part of the limbic system.Fear: The affective response to an actual current external danger which subsides with the elimination of the threatening condition.Polymorphism, Single Nucleotide: A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.Ocular Motility Disorders: Disorders that feature impairment of eye movements as a primary manifestation of disease. These conditions may be divided into infranuclear, nuclear, and supranuclear disorders. Diseases of the eye muscles or oculomotor cranial nerves (III, IV, and VI) are considered infranuclear. Nuclear disorders are caused by disease of the oculomotor, trochlear, or abducens nuclei in the BRAIN STEM. Supranuclear disorders are produced by dysfunction of higher order sensory and motor systems that control eye movements, including neural networks in the CEREBRAL CORTEX; BASAL GANGLIA; CEREBELLUM; and BRAIN STEM. Ocular torticollis refers to a head tilt that is caused by an ocular misalignment. Opsoclonus refers to rapid, conjugate oscillations of the eyes in multiple directions, which may occur as a parainfectious or paraneoplastic condition (e.g., OPSOCLONUS-MYOCLONUS SYNDROME). (Adams et al., Principles of Neurology, 6th ed, p240)Anti-Anxiety Agents: Agents that alleviate ANXIETY, tension, and ANXIETY DISORDERS, promote sedation, and have a calming effect without affecting clarity of consciousness or neurologic conditions. ADRENERGIC BETA-ANTAGONISTS are commonly used in the symptomatic treatment of anxiety but are not included here.Central Nervous System Diseases: Diseases of any component of the brain (including the cerebral hemispheres, diencephalon, brain stem, and cerebellum) or the spinal cord.Heredodegenerative Disorders, Nervous System: Inherited disorders characterized by progressive atrophy and dysfunction of anatomically or physiologically related neurologic systems.