Agreeableness  -  A dimension of personality and one of the five factors of the Big Five theory of personality, this term assesses the individual's willingness to empathize and cooperate with others. On the agreeableness scale, qualities of interpersonal orientation lie along a continuum from compassion, helpfulness, and cooperation to cynicism, antagonism, and manipulation.

Antisocial Personality Disorder  -  Part of Cluster B of the personality disorders, ASPD is characterized by aggressive behavior and a persistent disregard for, and frequent violation of, other people's rights.

Atypical Neuroleptics (Atypical Antipsychotics)  -  A type of drug, such as clozapine (Clozaril), that has been proven effective in treating the positive symptoms of schizophrenia, and, to a lesser extent, SPD. These drugs, however, unlike traditional neuroleptics and antipsychotic medication, do not produce extrapyramidal motor side effects (EPS), such as those resembling Parkinson's disease, and is not associated with an increased risk of tardive dyskinesia (TD).

Authoritarian  -  Both a personality syndrome and a style of parenting, "authoritarian" refers to a cluster of traits reflecting a desire for security and order, structured lines of authority, adherence to conventional rules, rigidity, unquestioning obedience, and scapegoating (which may sometimes lead to prejudice and ethnocentrism). Individuals of this personality style are very attracted to the status quo, protecting and serving the authority they see as maintaining it, and punishing individuals who threaten it. Authoritarian parents are very strict, value obedience, and will assert great force and power to maintain that obedience and control over their children.

Avoidant Personality Disorder  -  Part of Cluster C of the personality disorders, avoidant personality disorder is characterized by social discomfort, timidity, low self-esteem, hypersensitivity to potential rejection, shame, and humiliation, and fear of such negative evaluation. Individuals suffering from this disorder tend to be socially isolated, and although they desire acceptance and affection from others, they are hurt by even minimal signs of disapproval, and therefore attempt to avoid social situations entirely.

Axis I  -  Part of the DSM-IV classification system, this axis is concerned with symptomatic behavior that is usually ego-dystonic and characterized by episodic periods of psychological turmoil, such as schizophrenia and mood disorders. A diagnosis of an Axis I disorder does not exclude the individual from being diagnosed with an Axis II disorder as well if he or she meets the criteria for more than one disorder.

Axis II  -  Part of the DSM-IV classification system, this axis is concerned with symptomatic disorders that are usually ego-syntonic and characterized by more stable, long-standing problems, such as personality disorders and mental retardation. In addition, a diagnosis of an Axis II disorder does not exclude the individual from being diagnosed with an Axis I disorder if he or she meets the criteria for more than one disorder.

Big Five Theory of Personality  -  A dimensional and reliable approach to classifying personality across five factors: neuroticism; extroversion; openness to experience; agreeableness; and conscientiousness.

Borderline Personality Disorder  -  Part of Cluster B of the personality disorders, borderline personality disorder, so termed because individuals suffering form this disorder tend to be on the borderline between a psychotic and neurotic disorder, is characterized by an instability in mood, self-image, and interpersonal relationships, and by marked impulsivity. Manifestations of this disorder include frantic efforts to avoid real or imagined threats of abandonment, with opinions of significant others fluctuating between unrealistic positive and negative extremes. In addition individuals in this category tend to engage in para-suicidal behaviors, such as cutting themselves.

Conscientiousness  -  A dimension of personality and one of the five factors of the Big Five theory of personality, this term assesses an individual's organizational skills, dependability in finishing required tasks, and persistence in meeting goals. High conscientiousness describes individuals who are organized, reliable, and ambitious, while low conscientiousness is characterized by aimlessness, laziness, and unreliability.

Continuous Performance Task (CPT)  -  A testing measure which assesses one's ability to maintain attention on one object and measures the ability to selectively look at new stimuli, and therefore requires both vigilance and selective attention. This test may serve as a good index of vulnerability for developing schizophrenia and other disorders that lie on the schizophrenic spectrum, since patients with schizophrenia and their relatives tend to perform very poorly on CPTs.

Dependent Personality Disorder  -  Part of Cluster C of the personality disorders, dependent personality disorder is characterized by a pattern of dependent and submissive behavior. Individuals in this category, unable to make everyday decisions on their own and stricken with feelings of anxiety and helplessness when alone, tend to passively allow others to assume the responsibility for making decisions and constantly seek the advice and reassurance of other people.

Dialectical Behavior Therapy (DBT)  -  Proven to be a promising treatment of borderline individuals, DBT utilizes traditional behavioral and cognitive techniques, such as problem solving and skills training, to teach the patient how to improve and maintain interpersonal relationships, and how to cope with stress. In addition, a very important element of this form of treatment is that great emphasis is placed on the therapist's acceptance of the contradictory, demanding, and often manipulative behaviors of the patient.

Ego-Syntonic  -  The opposite of ego-dystonic, this term refers to behavior or mental acts, such as thoughts, feelings, and desires, which are seen as acceptable to the aims of the ego and the related psychological needs of the individual. The individual usually fails to see this behavior as a problem and simply considers it as part of their identity.

Ego-Dystonic  -  The opposite of ego-syntonic, this term refers to behavior or mental acts, such as thoughts, feelings, and desires, which are repugnant or at odds with the aims of the ego and the related psychological needs of the individual. The individual usually realizes that the behavior is at odds with their concept of self.

Extroversion  -  A dimension of personality and one of the five factors of the Big Five theory of personality, this term assesses the individual's ability to express positive emotions, and his or her activity level, especially interest, quantity, and intensity of interaction with other people. "High extroversion" characterizes individuals who are sociable, fun-loving, and talkative, while "low extroversion" identifies people who are reserved, quiet, and sober.

Genotype  -  The actual genetic constitution, or structure, of an individual.

Histrionic Personality Disorder  -  Part of Cluster B of the personality disorders, histrionic personality disorder is characterized by excessive emotionality, overreaction to everything, and attention-seeking behavior. Individuals with this disorder are self- centered, vain, and demanding, and possess shallow emotions that fluctuate rapidly.

Homovanillic Acid (HVA)  -  A metabolite, or waste product, of dopamine that can be used to assess the levels of dopamine in the brain. In addition, HVA levels have been found to have a positive correlation with the psychotic symptoms associated with SPD.

Hypothalamic-Pituitary-Adrenal Axis (HPA)  -  An important pathway of the endocrine system, the hypothalamic-pituitary-adrenal axis serves as a hormone relay station and thus plays an important role in maintaining stress levels. Signals form the hypothalamus cause the pituitary gland to secrete a hormone called ACTH. ACTH is responsible for controlling and modulating hormone secretion by the adrenal glands. The HPA pathway may also play a role in the development of depression, which may be the result of abnormalities and dysfunctions in the endocrine system, more specifically, high levels of the hormone cortisol. In addition, in individuals with SPD, HPA activity has been found to correlate positively with levels of anhedonia (an inability to experience pleasure) and social withdrawal.

Narcissistic Personality Disorder  -  Part of Cluster B of the personality disorders, narcissistic personality disorder is characterized by a grandiose view of self and an inability to empathize with others, for individuals suffering from this disorder are too preoccupied with their own achievements and abilities.

Neuroticism  -  A dimension of personality and one of the factors of the Big Five theory of personality, this term assesses emotional stability and the ability to express negative emotions, usually identifying individual's who have maladaptive coping mechanisms and are therefore more likely to suffer psychological distress. People high in neuroticism tend to be very anxious, insecure, and full of worry, while those low in neuroticism can be described as calm, secure, and self-satisfied.

Obsessive-Compulsive Personality Disorder (OCPD)  -  Part of Cluster C of the personality disorders, OCPD characterizes individuals who are inflexible, extremely inhibited, and who strive for perfectionism. These individuals tend be preoccupied with conformity to rules and standards and efficiency; therefore, they are excessively conscientious, moralistic, and judgmental.

Openness to Experience  -  A dimension of personality and one of the five factors of the Big Five theory of personality, this term assesses an individual's willingness to explore, consider, and tolerate new and unfamiliar experiences, ideas, and feelings. High scorers on this factor tend to be curious, imaginative, independent individuals, while low scorers are usually unimaginative, conventional, and conformist.

Overactive Reward System  -  A psychological theory proposing that ASPD may be the result of an overactive reward system, meaning that once there has been some reward in sight, individuals suffering from this disorder are unable to move away from the established goal even if the situation changes.

Paranoid Personality Disorder (PPD)  -  Part of Cluster A of the personality disorders, PPD is characterized by hypersensitivity, rigidity, jealousy, unwarranted suspicion of other people's motives and behavior, the belief that others are evil and attempting to inflict harm, and, therefore, the tendency to take extraordinary precautions to avoid being harmed or exploited.

Parental Communication Deviance  -  A descriptive measure, which may also serve as a possible risk factor, characterized by strange communication problems and loose associations with words. High levels of parental communication deviance in the home environment may serve as an indication of a disorder lying somewhere on the continuum of the schizophrenic spectrum.

Pathological  -  In the context of personality disorders, "pathological" describes the fact that disorders or the resulting behavior usually lead to social or occupational problems and personal distress to the individual.

Perceptual Allusions  -  Characteristic of individuals suffering from SPD, perceptual allusions are psychotic symptoms similar to delusions and hallucinations but not as fully developed or as severe.

Persistent  -  Stable over time. A defining characteristic of personality disorders, "persistent" refers to the fact that disorders or resulting behavior usually begin by early adulthood and exist throughout the individual's lifetime.

Personality  -  A stable and enduring pattern of perceiving, reacting, and interacting with the environment. Personality is the combination of persistent traits, such as relatively consistent patterns of thought and feeling, that describes a person's behavior or characterizes that person as a unique individual.

Personality Disorders  -  Inflexible and maladaptive patterns of interacting with the world. These patterns are usually characterized by three elements: they are pervasive, persistent, and pathological.

Pervasive  -  Consistent across situations. A defining characteristic of personality disorders, "pervasive" refers to the fact that the disorders or the resulting behavior remains true and present across situations.

Phenotype  -  The observed expression or physical manifestation, such as hair color, of a given genotype or genetic structure.

Schizoid Personality Disorder  -  Part of Cluster A of the personality disorders, schizoid personality disorder is characterized by a pervasive indifference to other people, coupled with a diminished range of emotional experience and expression. Individuals in this category are socially isolated and withdrawn, emotionally cold, or aloof, and therefore have few social relationships or friends.

Schizophrenic Spectrum  -  A group of disorders, including schizotypal personality disorder, delusional disorder and schizoaffective disorder, which, based on the evidence provided by family and adoption studies, may be genetically related to, or different manifestations of, schizophrenia.

Schizotypal Personality Sisorder (SPD)  -  Possibly part of the schizophrenic spectrum and one of the Cluster A personality disorders, SPD is characterized not only by a discomfort with other people, but also by peculiar and unusual patterns of thinking and behavior and eccentric behavior in the form of cognitive and perceptual disturbances.

Selective Attention  -  Attention is the process wherein mental activity is focused along a specific track, regardless of whether this track consists of inner memories and knowledge or is centered on an external stimulus. Selective attention, more specifically, concerns not only the ability to maintain attention on one singled-out object, but also the ability to selectively look at new stimuli.

Skin Conductance Orienting Response (SCOR)  -  A testing measure that assesses attentional skills and deficits. Basically, on this test, normal people exhibit increases in electrical activity (a type of physiological change that occurs in the skin) when a stimulus is changed. Individuals with schizophrenia and SPD, however, do not exhibit this selective criterion.

Stereotype  -  A mental concept or belief about a group of people, such as a particular race or ethnic group, that exaggerates differences between groups and minimizes differences among individual members within each group. Stereotypes, which are usually false and contain an element of hostility, tend to serve as the basis for prejudicial and discriminatory acts and events.

Thematic Apperception Test (TAT)  -  A widely used projective test that attempts to access personal attitudes and feelings that may be normally hidden. In this type of psychological test, standard, ambiguous pictures involving one or more people and depicting life- situations, is presented, and a the subject is asked to tell a story about each picture.

Theory of Parental Seductiveness  -  A psychological theory which proposes that individuals who exhibit histrionic personality disorder had parents who chastised them for sexual behavior, while actually encouraging it at the same time. This led to conflicting signs concerning sexual indulgence and subsequently to over-theatrical performances. One basis of this theory comes from the observation that the characteristic of emotional overreaction exhibited by individuals suffering from histrionic personality disorder usually tends to have a sexual element or suggestion.

Weak Behavioral Inhibition System  -  A psychological theory proposing that ASPD is caused by abnormalities within the individual's behavioral inhibition system. The system is responsible for deterring the individual from engaging in activities and behavior that may incur punishment. This theory is based on the observation that psychopaths tend to exhibit a type of habituation to punishment, wherein their physiological reaction to punishment and pain is very weak.