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Key Terms

PsychologyKey Terms

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
childhood disorder characterized by inattentiveness and/or hyperactive, impulsive behavior
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
co-occurrence of two disorders in the same individual
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
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 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 thinking
disjointed and incoherent thought processes, usually detected by what a person says
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
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 his or her 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 his or her 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
cause or causes of a psychological disorder
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
perceptual experience that occurs in the absence of external stimulation, such as the auditory hallucinations (hearing voices) common to schizophrenia
harmful dysfunction
model of psychological disorders resulting from the inability of an internal mechanism to perform its natural function
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
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
study of psychological disorders, including their symptoms, causes, and treatment; manifestation of a psychological disorder
in depression, tendency to repetitively and passively dwell on one’s depressed symptoms, their meanings, and their consequences
safety behavior
mental and behavior acts designed to reduce anxiety in social situations by reducing the chance of negative social outcomes; common in social anxiety disorder
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
death caused by intentional, self-directed injurious behavior
describes a force beyond scientific understanding
one of the fluid-filled cavities within the brain
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