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Essential Concepts
Defining Psychological Disorders
Psychological disorders are characterized by abnormal thoughts, feelings, and behaviors, but determining what constitutes a disorder is a complex task. Harmful dysfunction describes the view that psychological disorders result from the inability of an internal mechanism to perform its natural function. Many of the features of harmful dysfunction conceptualization have been incorporated in the APA’s formal definition of psychological disorders. According to this definition, the presence of a psychological disorder is signaled by significant disturbances in thoughts, feelings, and behaviors; these disturbances must reflect some kind of dysfunction (biological, psychological, or developmental), must cause significant impairment in one’s life, and must not reflect culturally expected reactions to certain life events.
The DSM-5 is the classification system widely used to diagnose and study psychological disorders, providing explicit criteria for each disorder. The International Classification of Diseases (ICD) is a comprehensive classification system used for healthcare worldwide, including mental health, and is published by the World Health Organization (WHO), while the Diagnostic and Statistical Manual of Mental Disorders (DSM) is favored for research and clinical diagnosis in the United States.
Psychopathology integrates biological (e.g. faulty biological processes) and psychosocial (e.g. stress and environment) perspectives on the origin of psychological disorders. The diathesis-stress model proposes that individuals with underlying vulnerabilities are more likely to develop a disorder when exposed to stressful events.
Anxiety and Related Disorders
Anxiety disorders are a group of disorders in which a person experiences excessive, persistent, and distressing fear and anxiety that interferes with normal functioning. Anxiety disorders include specific phobia: a specific unrealistic fear; social anxiety disorder: extreme fear and avoidance of social situations; panic disorder: suddenly overwhelmed by panic even though there is no apparent reason to be frightened; agoraphobia: an intense fear and avoidance of situations in which it might be difficult to escape; and generalized anxiety disorder: a relatively continuous state of tension, apprehension, and dread.
Obsessive-compulsive and related disorders in the DSM-5 involve intrusive thoughts and/or repetitive behaviors. This includes obsessive-compulsive disorder with unwanted thoughts and repetitive actions, body dysmorphic disorder with excessive preoccupation about physical flaws, and hoarding disorder characterized by difficulty discarding objects leading to cluttered living spaces.
PTSD, formerly known as shell shock and combat neurosis, is now defined as a disorder resulting from a traumatic or highly stressful event, with symptoms lasting one month or longer. These symptoms include intrusive memories, flashbacks, avoidance, negative emotions, detachment, irritability, and hypervigilance. Not everyone who experiences trauma develops PTSD, as there are identified risk factors associated with its development.
Depression and Related Disorders
Mood disorders are those in which the person experiences severe disturbances in mood and emotion. They include depressive disorders and bipolar and related disorders. Depressive disorders include major depressive disorder, which is characterized by episodes of profound sadness and loss of interest or pleasure in usual activities and other associated features, and persistent depressive disorder, which marked by a chronic state of sadness.
Bipolar disorder is characterized by mood states that vacillate between sadness and euphoria; a diagnosis of bipolar disorder requires experiencing at least one manic episode, which is defined as a period of extreme euphoria, irritability, and increased activity. During a manic episode, a person will likely exhibit behaviors atypical for that person. They may become excessively talkative, exhibit flight of ideas, and make grandiose plans. They may go on a spending spree, maxing out their credit card with items they can not afford, gamble, or engage in risky sexual behaviors. About fifty percent of people suffering from bipolar disorder do not receive treatment. Bipolar disorder is a definitive risk factor for suicide, with about a third of people with bipolar disorder attempting suicide.
When a person’s pain and distress completely overwhelm their ability to cope, some people may consider suicide. People who suffer from mental health and substance abuse problems are at a much higher risk of suicide than the general public. Males die by suicide at a significantly higher rate than females, and males use much more lethal means in their attempts. A person contemplating suicide needs help and should not have access to lethal means of suicide, such as firearms. If you or someone you know is contemplating suicide, there are many helpful resources. Three of them are listed below:
- Visit National Suicide Prevention Lifeline, call 1-800-273-8255, or text the Crisis Text Line (text HELLO to 741741).
- Visit the American Foundation for Suicide Prevention.
- Visit The National Institute of Health Website page on suicide.
Schizophrenia and Related Disorders
Schizophrenia is a severe disorder that leads to a breakdown in functioning and often requires hospitalization. It is characterized by hallucinations, delusions, incoherent thinking, bizarre behavior, flat emotions, and lack of motivation. Genetic factors play a central role, while environmental factors and neurotransmitter abnormalities are also implicated. A promising new area of schizophrenia research involves identifying individuals who show prodromal symptoms and following them over time to determine which factors best predict the development of schizophrenia. Future research may enable us to pinpoint those especially at risk for developing schizophrenia and who may benefit from early intervention.
The main characteristic of dissociative disorders is that people become dissociated from their sense of self, resulting in memory and identity disturbances. Dissociative disorders listed in the DSM-5 include dissociative amnesia, depersonalization/derealization disorder, and dissociative identity disorder. A person with dissociative amnesia is unable to recall important personal information, often after a stressful or traumatic experience.
Depersonalization/derealization disorder is characterized by recurring episodes of depersonalization (i.e., detachment from or unfamiliarity with the self) and/or derealization (i.e., detachment from or unfamiliarity with the world). A person with dissociative identity disorder exhibits two or more well-defined and distinct personalities or identities, as well as memory gaps for the time during which another identity was present.
Dissociative identity disorder has generated controversy, mainly because some believe its symptoms can be faked by patients if presenting its symptoms somehow benefits the patient in avoiding negative consequences or taking responsibility for one’s actions. The diagnostic rates of this disorder have increased dramatically following its portrayal in popular culture. However, many people legitimately suffer over the course of a lifetime with this disorder.
Personality Disorders
Individuals with personality disorders exhibit a personality style that is inflexible, causes distress and impairment, and creates problems for themselves and others. The DSM-5 recognizes 10 personality disorders, organized into three clusters. The disorders in Cluster A include those characterized by a personality style that is odd and eccentric. Cluster B includes personality disorders characterized chiefly by a personality style that is impulsive, dramatic, highly emotional, and erratic, and those in Cluster C are characterized by a nervous and fearful personality style.
Two Cluster B personality disorders, borderline personality disorder and antisocial personality disorder, are especially problematic. People with borderline personality disorder show marked instability in mood, behavior, and self-image, as well as impulsivity. They cannot stand to be alone, are unpredictable, have a history of stormy relationships, and frequently display intense and inappropriate anger. Genetic factors and adverse childhood experiences (e.g., sexual abuse) appear to be important in its development. People with antisocial personality display a lack of regard for the rights of others; they are impulsive, deceitful, irresponsible, and unburdened by any sense of guilt. Genetic factors and socialization both appear to be important in the origin of antisocial personality disorder. Research has also shown that those with this disorder do not experience emotions the way most other people do.
Neurodevelopmental Disorders
Neurodevelopmental disorders are a group of disorders that are typically diagnosed during childhood and are characterized by developmental deficits in personal, social, academic, and intellectual realms; these disorders include attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder. ADHD is characterized by a pervasive pattern of inattention and/or hyperactive and impulsive behavior that interferes with normal functioning. Genetic and neurobiological factors contribute to the development of ADHD, which can persist well into adulthood and is often associated with poor long-term outcomes.
The major features of autism spectrum disorder include deficits in social interaction and communication and repetitive movements or interests. As with ADHD, genetic factors appear to play a prominent role in the development of autism spectrum disorder; exposure to environmental pollutants such as mercury have also been linked to the development of this disorder. Although it is believed by some that autism is triggered by the MMR vaccination, evidence does not support this claim.
Glossary
agoraphobia
anxiety disorder characterized by intense fear, anxiety, and avoidance of situations in which it might be difficult to escape if one experiences symptoms of a panic attack
antisocial personality disorder
characterized by a lack of regard for others’ rights, impulsivity, deceitfulness, irresponsibility, and lack of remorse over misdeeds
anxiety disorder
characterized by excessive and persistent fear and anxiety, and by related disturbances in behavior
attention deficit/hyperactivity disorder (ADHD)
childhood disorder characterized by inattentiveness and/or hyperactive, impulsive behavior
atypical
describes behaviors or feelings that deviate from the norm
autism spectrum disorder
childhood disorder characterized by deficits in social interaction and communication, and repetitive patterns of behavior or interests
bipolar and related disorders
group of mood disorders in which mania is the defining feature
bipolar disorder
mood disorder characterized by mood states that vacillate between depression and mania
body dysmorphic disorder
involves excessive preoccupation with an imagined defect in physical appearance
borderline personality disorder
instability in interpersonal relationships, self-image, and mood, as well as impulsivity; key features include intolerance of being alone and fear of abandonment, unstable relationships, unpredictable behavior and moods, and intense and inappropriate anger
catatonic behavior
decreased reactivity to the environment; includes posturing and catatonic stupor
cluster A
one of the three clusters as part of the DSM-5’s 10 personality orders; the disorders in cluster A include those characterized by a personality style that is odd and eccentric (paranoid, schizoid, and schizotypal personality disorders)
cluster B
one of the three clusters as part of the DSM-5’s 10 personality orders; the disorders in cluster B include personality disorders characterized chiefly by a personality style that is impulsive, dramatic, highly emotional, and erratic (e.g., antisocial, histrionic, narcissistic, and borderline)
cluster C
one of the three clusters as part of the DSM-5’s 10 personality orders; the disorders in cluster C are characterized by a nervous and fearful personality style (avoidant, dependent, and obsessive-compulsive)
comorbidity
co-occurrence of two disorders in the same individual
delusion
belief that is contrary to reality and is firmly held, despite contradictory evidence
depersonalization/derealization disorder
dissociative disorder in which people feel detached from the self (depersonalization), and the world feels artificial and unreal (derealization)
depressive disorder
one of a group of mood disorders in which depression is the defining feature
diagnosis
determination of which disorder a set of symptoms represents
Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5)
authoritative index of mental disorders and the criteria for their diagnosis; published by the American Psychiatric Association (APA)
diathesis-stress
theory in which certain predispositions or vulnerability factors influence one’s reaction to stress
diathesis-stress model
suggests that people with a predisposition for a disorder (a diathesis) are more likely to develop the disorder when faced with stress; model of psychopathology
disorganized/abnormal motor behavior
highly unusual behaviors and movements (such as child-like behaviors), repeated and purposeless movements, and displaying odd facial expressions and gestures
disorganized thinking
disjointed and incoherent thought processes, usually detected by what a person says
dissociative amnesia
dissociative disorder characterized by an inability to recall important personal information, usually following an extremely stressful or traumatic experience
dissociative disorders
group of DSM-5 disorders in which the primary feature is that a person becomes dissociated, or split off, from their core sense of self, resulting in disturbances in identity and memory
dissociative fugue
symptom of dissociative amnesia in which a person suddenly wanders away from one’s home and experiences confusion about their identity
dissociative identity disorder
dissociative disorder (formerly known as multiple personality disorder) in which a person exhibits two or more distinct, well-defined personalities or identities and experiences memory gaps for the time during which another identity emerged
dopamine hypothesis
theory of schizophrenia that proposes that an overabundance of dopamine or dopamine receptors is responsible for the onset and maintenance of schizophrenia
etiology
cause or causes of a psychological disorder
flashback
psychological state lasting from a few seconds to several days, during which one relives a traumatic event and behaves as though the event were occurring at that moment
flight of ideas
symptom of mania that involves an abruptly switching in conversation from one topic to another
generalized anxiety disorder
characterized by a continuous state of excessive, uncontrollable, and pointless worry and apprehension
grandiose delusion
characterized by beliefs that one holds special power, unique knowledge, or is extremely important
hallucination
perceptual experience that occurs in the absence of external stimulation, such as the auditory hallucinations (hearing voices) common to schizophrenia
hoarding disorder
characterized by persistent difficulty in parting with possessions, regardless of their actual value or usefulness
hopelessness theory
cognitive theory of depression proposing that a style of thinking that perceives negative life events as having stable and global causes leads to a sense of hopelessness and then to depression
International Classification of Diseases (ICD)
authoritative index of mental and physical diseases, including infectious diseases, and the criteria for their diagnosis; published by the World Health Organization (WHO)
locus coeruleus
area of the brainstem that contains norepinephrine, a neurotransmitter that triggers the body’s fight-or-flight response; has been implicated in panic disorder
major depressive disorder
commonly referred to as “depression” or “major depression,” characterized by sadness or loss of pleasure in usual activities, as well other symptoms
mania
state of extreme elation and agitation
manic episode
period in which an individual experiences mania, characterized by extremely cheerful and euphoric mood, excessive talkativeness, irritability, increased activity levels, and other symptoms
mood disorder
one of a group of disorders characterized by severe disturbances in mood and emotions; the categories of mood disorders listed in the DSM-5 are bipolar and related disorders and depressive disorders
negative symptom
characterized by decreases and absences in certain normal behaviors, emotions, or drives, such as an expressionless face, lack of motivation to engage in activities, reduced speech, lack of social engagement, and inability to experience pleasure
neurodevelopmental disorder
one of the disorders that are first diagnosed in childhood and involve developmental problems in academic, intellectual, social functioning
obsessive-compulsive and related disorders
group of overlapping disorders listed in the DSM-5 that involves intrusive, unpleasant thoughts and/or repetitive behaviors
obsessive-compulsive disorder
characterized by the tendency to experience intrusive and unwanted thoughts and urges (obsession) and/or the need to engage in repetitive behaviors or mental acts (compulsions) in response to the unwanted thoughts and urges
orbitofrontal cortex
area of the frontal lobe involved in learning and decision-making
panic attack
period of extreme fear or discomfort that develops abruptly; symptoms of panic attacks are both physiological and psychological
panic disorder
anxiety disorder characterized by unexpected panic attacks, along with at least one month of worry about panic attacks or self-defeating behavior related to the attacks
paranoid delusion
characterized by beliefs that others are out to harm them
peripartum onset
subtype of depression that applies to women who experience an episode of major depression either during pregnancy or in the four weeks following childbirth
persistent depressive disorder
depressive disorder characterized by a chronically sad and melancholy mood
personality disorder
group of DSM-5 disorders characterized by an inflexible and pervasive personality style that differs markedly from the expectations of one’s culture and causes distress and impairment; people with these disorders have a personality style that frequently brings them into conflict with others and disrupts their ability to develop and maintain social relationships
posttraumatic stress disorder (PTSD)
experiencing a profoundly traumatic event leads to a constellation of symptoms that include intrusive and distressing memories of the event, avoidance of stimuli connected to the event, negative emotional states, feelings of detachment from others, irritability, proneness toward outbursts, hypervigilance, and a tendency to startle easily; these symptoms must occur for at least one month
prodromal symptom
in schizophrenia, one of the early minor symptoms of psychosis
psychological disorder
condition characterized by abnormal thoughts, feelings, and behaviors
psychopathology
study of psychological disorders, including their symptoms, causes, and treatment; manifestation of a psychological disorder
rumination
in depression, tendency to repetitively and passively dwell on one’s depressed symptoms, their meanings, and their consequences
safety behavior
mental and behavioral acts designed to reduce anxiety in social situations by reducing the chance of negative social outcomes; common in social anxiety disorder
schizophrenia
severe disorder characterized by major disturbances in thought, perception, emotion, and behavior with symptoms that include hallucinations, delusions, disorganized thinking and behavior, and negative symptoms
seasonal pattern
subtype of depression in which a person experiences the symptoms of major depressive disorder only during a particular time of year
social anxiety disorder
characterized by extreme and persistent fear or anxiety and avoidance of social situations in which one could potentially be evaluated negatively by others
somatic delusion
belief that something highly unusual is happening to one’s body or internal organs
specific phobia
anxiety disorder characterized by excessive, distressing, and persistent fear or anxiety about a specific object or situation
suicidal ideation
thoughts of death by suicide, thinking about or planning suicide, or making a suicide attempt
suicide
death caused by intentional, self-directed injurious behavior
supernatural
describes a force beyond scientific understanding
ventricle
one of the fluid-filled cavities within the brain