The observation of strange behavior depends at least in part upon the perceptions of the observer. For most people, behaviors that are observed as out of the ordinary or strange are a feature of psychotic disorders, mood disorders, and other mental-health conditions. Examples of conditions in which psychosis (altered perception of reality) are present include schizophrenia, delusional disorder, and schizoaffective disorder. People suffering from psychosis may have an altered perception of reality that often affects their behavior, leading them to act in ways that may be perceived as strange. Problems controlling one's behavior can also occur as a result of brain damage or disorders. People suffering from dementia may display strange behaviors. Behavioral changes can be accompanied by other psychiatric symptoms or by physical symptoms if they are related to a medical condition. Substance abuse and drug overdoses can also lead to problems with behavior.
Other causes of unusual behavior
- Brain Trauma
- Catastrophic Life Events
- Conduct Disorder
- Cyclothymia
- Delusional Disorder
- Drug-Induced Psychosis
- Oppositional Defiant Disorder
SLIDESHOW
17 Everyday Ways to Ease Depression See SlideshowPictures, Images, Illustrations & Quizzes
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Alzheimer's Disease Symptoms & Early Diagnosis
Memory loss and confusion can be signs of normal aging, but also warning signs of Alzheimer's disease. The early stages of...
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Autism Signs in Children: What Is Autism Spectrum Disorder?
What is autism? Learn about the signs, symptoms, and diagnosis of autism spectrum disorder. Get information about the causes of...
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Panic Attacks (Panic Disorder) Quiz: Test Your Mental Health IQ
Could you suffer a panic attack? Take this Panic Attacks Quiz to learn causes, symptoms, and treatments for panic disorder. Use...
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Parkinson's Disease: Symptoms, Causes, Stages, Treatment
Discover the symptoms, causes, stages, and treatment options for Parkinson's disease. Learn more about the stages of Parkinson's...
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Teen Drug Abuse: Warning Signs, Statistics, and Facts
Teen drug abuse is a growing concern today. Learn statistics, facts, warning signs, and effects related to teen substance abuse...
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The Stages of Dementia: Alzheimer's Disease and Aging Brains
What are the symptoms of dementia? What causes dementia? Dementia includes many disorders, such as Lewy Body dementia,...
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What Happens After a Stroke? Signs, Symptoms, Types
What is a stroke? Learn about the different types of stroke, as well as many symptoms like sudden numbness or weakness,...
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What Is Bipolar Disorder? Symptoms, Manic Episodes, Testing
Bipolar disorder (formerly "manic depression") causes extreme mood shifts and manic episodes. Learn about bipolar 1, bipolar 2,...
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What's Schizophrenia? Symptoms, Types, Causes, Treatment
What is the definition of schizophrenia? What is paranoid schizophrenia? Read about schizophrenia types and learn about...
Causes of Unusual Behavior
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Alcoholism and Alcohol Abuse
Alcoholism is a disease that includes alcohol craving and continued drinking despite repeated alcohol-related problems, such as losing a job or getting into trouble with the law. It can cause myriad health problems, including cirrhosis of the liver, birth defects, heart disease, stroke, psychological problems, and dementia. Counseling and a few medications can be effective for alcoholism treatment.
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Alzheimer's Disease
Alzheimer's disease is a common cause of dementia. Symptoms and warning signs of Alzheimer's disease include memory loss, difficulty performing familiar tasks, disorientation to time and place, misplacing things, and more. The biggest risk factor for Alzheimer's disease is increased age. Treatment for Alzheimer's is often targeted toward decreasing the symptoms and progression of the disease.
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Anxiety
Anxiety is a feeling of apprehension and fear characterized by symptoms such as trouble concentrating, headaches, sleep problems, and irritability. Anxiety disorders are serious medical illnesses that affect approximately 19 million American adults. Treatment for anxiety may incorporate medications and psychotherapy.
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Autism Spectrum Disorder
Autism in children and adults is a developmental disorder, characterized by impaired development in communication, social interaction, and behavior. Autism is classified as a pervasive developmental disorder (PDD), which is part of a broad spectrum of developmental disorders affecting young children and adults. There are numerous theories and studies about the cause of autism. The treatment model for autism is an educational program that is suitable to an individual's developmental level of performance. There is no "cure" for autism.
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Bipolar Disorder in Children, Teens, and Adults
Bipolar disorder (or manic depression) is a mental illness characterized by depression, mania, and severe mood swings. Treatment may incorporate mood-stabilizer medications, antidepressants, and psychotherapy.
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Dementia
Dementia is defined as a significant loss of intellectual abilities such as memory capacity, severe enough to interfere with social or occupational functioning. There are several different types of dementia, including cortical, subcortical, progressive, primary, and secondary dementias. Other conditions and medication reactions can also cause dementia. Dementia is diagnosed based on a certain set of criteria. Treatment for dementia is generally focused on the symptoms of the disease.
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Depression
Depression is an illness that involves the body, mood, and thoughts and affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. The principal types of depression are major depression, dysthymia, and bipolar disease (also called manic-depressive disease).
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Drug Abuse and Addiction
Drug abuse and addiction is a chronic disease that causes drug-seeking behavior and drug use despite negative consequences to the user and those around him. Though the initial decision to use drugs is voluntary, changes in the brain caused by repeated drug abuse can affect a person's self-control and ability to make the right decisions and increase the urge to take drugs. Drug abuse and addiction are preventable.
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Dysthymia
Dysthymia is a less severe form of chronic depression. Symptoms and signs include insomnia, suicidal thoughts, guilt, empty feeling, loss of energy, helplessness, sluggishness, and persistent aches and pains. Treatment may involve psychotherapy, electroconvulsive therapy, and antidepressants.
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Human Immunodeficiency Virus (HIV)
HIV (human immunodeficiency virus) infection left untreated causes AIDS (acquired immunodeficiency syndrome). The human immunodeficiency virus (HIV) is a type of virus called a retrovirus, which can infect humans when it comes in contact with tissues that line the vagina, anal area, mouth, or eyes, or through a break in the skin. HIV infection is generally a slowly progressive disease in which the virus is present throughout the body at all stages of the disease. Three stages of HIV infection have been described. The initial stage of infection (primary infection), which occurs within weeks of acquiring the virus, often is characterized by the flu- or mono-like illness that generally resolves within weeks. The stage of chronic asymptomatic infection (meaning a long duration of infection without symptoms) lasts an average of eight to 10 years without treatment. The stage of symptomatic infection, in which the body's immune (or defense) system has been suppressed and complications have developed, is called the acquired immunodeficiency syndrome (AIDS). The symptoms are caused by the complications of AIDS, which include one or more unusual infections or cancers, severe loss of weight, and intellectual deterioration (called dementia). When HIV grows (that is, by reproducing itself), it acquires the ability to change (mutate) its own structure. These mutations enable the virus to become resistant to previously effective drug therapy. The goals of drug therapy are to prevent damage to the immune system by the HIV virus and to halt or delay the progress of the infection to symptomatic disease. Therapy for HIV includes combinations of drugs that decrease the growth of the virus to such an extent that the treatment prevents or markedly delays the development of viral resistance to the drugs. The best combination of drugs for HIV are those that effectively suppress viral replication in the blood and also are well tolerated and simple to take so that people can take the medications consistently without missing doses.
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Panic Attacks
Panic attacks are sudden feelings of terror that strike without warning. These episodes can occur at any time, even during sleep. A person experiencing a panic attack may believe that he or she is having a heart attack or that death is imminent. The fear and terror that a person experiences during a panic attack are not in proportion to the true situation and may be unrelated to what is happening around them. Most people with panic attacks experience several of the following symptoms: racing heartbeat, faintness, dizziness, numbness or tingling in the hands and fingers, chills, chest pains, difficulty breathing, and a feeling of loss or control. There are several treatments for panic attacks.
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Parkinson's Disease
Parkinson's disease is a slowly progressive neurological disease characterized by a fixed inexpressive face, a tremor at rest, slowing of voluntary movements, a gait with short accelerating steps, peculiar posture and muscle weakness, caused by degeneration of an area of the brain called the basal ganglia, and by low production of the neurotransmitter dopamine. Most patients are over 50, but at least 10 percent are under 40.
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Peanut Allergy
Peanut allergies causes signs and symptoms that include hives, itching, redness, and a rash. Severe reactions may cause decreased blood pressure, lightheadedness, difficulty breathing, nausea, and behavioral changes. Someone with a peanut allergy should have an EpiPen with them at all times.
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Phobias
Phobias are unrelenting fears of activities (social phobias), situations (agoraphobia), and specific items (arachnophobia). There is thought to be a hereditary component to phobias, though there may be a cultural influence or they may be triggered by life events. Symptoms and signs of phobias include having a panic attack, shaking, breathing troubles, rapid heartbeat, and a strong desire to escape the situation. Treatment of phobias typically involves desensitization, cognitive behavioral therapy, and medications such as selective serotonin reuptake inhibitors and beta-blockers.
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Post-traumatic Stress Disorder
Post-traumatic stress disorder (PTSD), a psychiatric condition, can develop after any catastrophic life event. Symptoms include nightmares, flashbacks, sweating, rapid heart rate, detachment, amnesia, sleep problems, irritability, and exaggerated startle response. Treatment may involve psychotherapy, group support, and medication.
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Postpartum Depression
Postpartum depression is a form of depression that occurs within a year after delivery. It is thought that rapid hormone changes after childbirth may lead to depression. Symptoms of postpartum depression include crying a lot, headaches, chest pains, eating too little or too much, sleeping too little or too much, withdrawal from friends and family, and feeling irritable, sad, hopeless, worthless, guilty, and overwhelmed. Treatment typically involves talk therapy and medication.
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Psychotic Disorders
Psychotic disorders are a group of serious illnesses that affect the mind. Different types of psychotic disorders include schizophrenia, schizoaffective disorder, schizophreniform disorder, brief psychotic disorder, shared psychotic disorder, delusional disorder, substance-induced psychotic disorder, paraphrenia, and psychotic disorders due to medical conditions.
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Schizoaffective Disorder
Schizoaffective disorder is a mental illness that features schizophrenia and a mood disorder, either major depression or bipolar disorder. Symptoms include agitation, suicidal thoughts, little need for sleep, delusions, hallucinations, and poor motivation. Treatment may involve psychotherapy, medication, skills training, or hospitalization.
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Schizophrenia
Schizophrenia is a disabling brain disorder that may cause hallucinations and delusions and affect a person's ability to communicate and pay attention. Symptoms of psychosis appear in men in their late teens and early 20s and in women in their mid-20s to early 30s. With treatment involving the use of antipsychotic medications and psychosocial treatment, schizophrenia patients can lead rewarding and meaningful lives.
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Seasonal Affective Disorder (SAD)
Seasonal affective disorder is a type of depression that tends to occur as the days grow shorter in the fall and winter. Symptoms of seasonal affective disorder include tiredness, fatigue, depression, irritability, body aches, poor sleep, and overeating.
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Stroke
A stroke is an interruption of the blood supply to part of the brain caused by either a blood clot (ischemic) or bleeding (hemorrhagic). Symptoms of a stroke may include weakness, numbness, double vision or vision loss, confusion, vertigo, difficulty speaking, or understanding speech. A physical exam, imaging tests, neurological exam, and blood tests may be used to diagnose a stroke. Treatment may include administration of clot-busting drugs, supportive care, and in some instances, neurosurgery. The risk of stroke can be reduced by controlling high blood pressure, high cholesterol, diabetes, and stopping smoking.
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What Is Oppositional Defiant Disorder (ODD) in a Person?
Oppositional defiant disorder (ODD) is a behavior disorder in which a child displays frequent patterns of anger, arguing, or defiance towards authority figures. Symptoms of ODD may include frequently losing temper, being annoyed by others, arguing with adults, refusing to comply with adult requests, refusing to follow orders and rules, deliberately trying to annoy or upset people, blaming others for their own mistakes or misbehavior, and being spiteful or vindictive.
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What Is Schizotypal Personality Disorder?
Schizotypal personality disorder is characterized by odd behaviors, feelings, perceptions, and ways of relating to others that interfere with one's ability to function. Medication and psychotherapy can help the sufferer to manage their symptoms.
Examples of Medications for Unusual Behavior
- aripiprazole (Abilify)
- bupropion
- chlorpromazine - oral, Thorazine
- chlorpromazine-injection, Thorazine
- Citalopram
- clozapine (Clozaril, Fazacio ODT, Versacloz)
- desvenlafaxine (Pristiq, Khedezla)
- duloxetine
- escitalopram
- fluoxetine
- fluphenazine (Permitil, Prolixin)
- fluphenazine concentrate - oral, Prolixin
- fluphenazine liquid - oral, Prolixin
- haloperidol
- olanzapine (Zyprexa, Zydis)
- paroxetine (Paxil, Pexeva)
- quetiapine (Seroquel)
- risperidone, Risperdal; Risperdal Consta, Risperdal M-TAB
- sertraline
- thiothixene - oral, Navane
- venlafaxine
- ziprasidone (Geodon)
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