| Amygdala | A part of the brain's limbic system that attaches emotional significance to information and mediates both defensive and aggressive behavior. |
| Anal Expulsive Personality | Stemming from the Anal stage, a child who becomes fixated due to over control transfers his or her unresolved anal (or control) issues into characteristics such as cruelty, pushiness, messiness, or disorganization. |
| Anal Retentive Personality | Stemming from the Anal stage, a child who becomes fixated due to under control transfers his or her unresolved anal (or control) issues into characteristics such as compulsivity, stinginess, cleanliness, organization, and obstinance. |
| Anal Stage | Freud's second stage of psychosexual development where the primary sexual focus is on the elimination or holding onto feces. The stage is often thought of as representing a child's ability to control his or her own world. |
| Analysis | See Psychoanalysis. |
| Autonomic Nervous System | Part of the peripheral nervous system that regulates the involuntary actions of the body (e.g., breathing, heart rate, blood pressure, pupil dilation). Also regulates the Fight or Flight Phenomenon. |
| Availability Heuristic | A rule of thumb stating that information more readily available in our memory is more important than information not as easily accessible. |
| Aversion Therapy | A type of behavioral treatment where an aversive stimuli is paired with a negative behavior in hopes that the behavior will change in the future to avoid the aversive stimuli. |
| Avoidance-Avoidance Conflict | The conflict where both possible choices have an equal negative outcome. |
| Axon | The tail-like part of the neuron through which information exits the cell. |
| Binocular Cues | Visual cues (convergence and retinal disparity) that require both eyes to perceive distance (as opposed to monocular cues) |
| Bisexuality | Being attracted to or aroused by members of both genders. See Sexual Orientation. |
| Blind Study | As a way to avoid the placebo effect in research, this type of study is designed without the subject's knowledge of the anticipated results and sometimes even the nature of the study. The subjects are said to be 'blind' to the expected results. |
| Broca's Aphasia | An aphasia associated with damage to the Broca's area of the brain, demonstrated by the impairment in producing understandable speech. |
| Burnout | Changes in thoughts, emotions, and behavior as a result of extended job stress and unrewarded repetition of duties. Burnout is seen as extreme dissatisfaction, pessimism, lowered job satisfaction, and a desire to quit. |
| Chemical Imbalance | A generic term for the idea that chemical in the brain are either too scarce or too abundant resulting in or contributing to a mental disorder such as schizophrenia or bipolar disorder. Others believe that the disorder precedes the imbalance, suggesting that a change in mood, for example, changes our chemicals rather than the chemical changing our mood. |
| Chunk | A unit of information used in memory |
| Chunking | Combining smaller units of measurement or chunks into larger chunks. (e.g., a seven chunk phone number such as 5-5-5-1-2-1-2 becomes a five chunk number such as 5-5-5-12-12) |
| Classical Conditioning | The behavioral technique of pairing a naturally occurring stimulus and response chain with a different stimulus in order to produce a response which is not naturally occurring. |
| Client Centered Therapy | A humanistic therapy based on Carl Roger's beliefs that an individual has an unlimited capacity for psychological growth and will continue to grow unless barriers are placed in the way. |
| Coefficient of Determination | The statistic or number determined by squaring the correlation coefficient. Represents the amount of variance accounted for by that correlation. |
| Coercive Power | Power derived through the ability to punish. |
| Cognition | The process of receiving, processing, storing, and using information. |
| Cognitive Behavioral Therapy | Treatment involving the combination of behaviorism (based on the theories of learning) and cognitive therapy (based on the theory that our cognitions or thoughts control a large portion of our behaviors). |
| Cognitive Dissonance | The realization of contradictions in one's own attitudes and behaviors. |
| Cognitive Psychology | The sub-field of psychology associated with information processing and the role it plays in emotion, behavior, and physiology. |
| Cognitive Therapy | The treatment approach based on the theory that our cognitions or thoughts control a large part of our behaviors and emotions. Therefore, changing the way we think can result in positive changes in the way we act and feel. |
| Cohort Effects | The effects of being born and raised in a particular time or situation where all other members of your group has similar experiences that make your group unique from other groups |
| Collective Unconscious | According to Jung, the content of the unconscious mind that is passed down from generation to generation in all humans. |
| Compulsion | The physical act resulting from an obsession. Typically a compulsive act is done in an attempt to alleviate the discomfort created by an obsession. |
| Concrete Operational Stage | According to Piaget, the stage of cognitive development where a child between the ages of 7 and 12 begins thinking more globally and outside of the self but is still deficient in abstract thought. |
| Concurrent Validity | A measurements ability to correlate or vary directly with an accepted measure of the same construct |
| Conditioned Response | The response in a stimulus-response chain that is not naturally occurring, but rather has been learned through its pairing with a naturally occurring chain. |
| Conditioned Stimulus | The stimulus in a stimulus-response chain that is not naturally occurring, but rather has been learned through its pairing with a naturally occurring chain. |
| Conditioning | The process of learning new behaviors or responses as a result of their consequences. |
| Convergence | The binocular cue to distance referring to the fact that the closer an object, the more inward our eyes need to turn in order to focus |
| Convergent Thinking | Logical and conventional thought leading to a single answer. |
| Conversion Disorder | A somatoform disorder where the individual experiences a loss of sensation or function due to a psychological belief (e.g., paralysis, blindness, deafness). |
| Correlated Sample | Sample data that is related to each other. |
| Correlation | The degree to which two or more variables a related to each other. A correlation refers to the direction that the variables move and does not necessarily represent cause and effect. (Example: height and weight are correlated. As one increases, the other tends to increase as well) |
| Cross Sequential Study | A research study that examines the effects of development (maturation) by combining longitudinal and cross sectional studies |
| Crowding | The psychological and psychological response to the belief that there are too many people in a specified area. |
| Crystallized Intelligence | The part of intelligence which involves the acquisition, as opposed to the use, of information |
| Decay | Theory which states that memory fades and/or disappears over time if it is not used or accessed. |
| Declarative Memory | The part of long-term memory where factual information is stored, such as mathematical formulas, vocabulary, and life events. |
| Deductive Reasoning | Decision making process in which ideas are processed from the general to the specific. |
| Defenses (Defense Mechanisms) | Psychological forces which prevent undesirable or inappropriate impulses from entering consciousness (e.g., forgetting responsibilities that we really didn't want to do, projecting anger onto a spouse as opposed to your boss). Also called Defense Mechanisms, Defense System, or Ego Defenses. |
| Degrees of Freedom | The number of individual scores that can vary without changing the sample mean. Statistically written as 'N-1' where N represents the number of subjects. |
| Delusion | False belief system (e.g., believing you are Napoleon, have magical powers, or the false belief that others are 'out to get you.'). |
| Dendrites | Extensions of the cell body of a neuron responsible for receiving incoming neurotransmitters. |
| Discrimination | In behavioral theory, the learned ability to differentiate between two similar objects or situations. |
| Disorientation | Inability to recognize or be aware of who we are (person), what we are doing (situation), the time and date (time), or where we are in relation to our environment (place). To be considered a problem, it must be consistent, result in difficulty functioning, and not due to forgetting or being lost. |
| Displacement | The pushing out of older information in short term memory to make room for new information. |
| Dispositional Attribute | An attribute explained or interpreted as being caused by internal influences. |
| Dissociation | A separation from the self, with the most severe resulting in Dissociative Identity Disorder. Most of us experience this in very mild forms such as when we are driving long distance and lose time or find ourselves day dreaming longer than we thought. |
| Error | The amount of other variables (aside from what you are measuring) that can impact the observed score |
| Error Level | The level of accepted error within a given set of data. The greater the error level, the wider the confidence interval. |
| Escape Conditioning | Operant conditioning based on the idea that a behavior is more likely to be repeated if it results in the cessation of a negative event. |
| Estimate | An idea about a characteristic of a population based on sample data (e.g., the sample mean IQ was 102 so we estimate that the population mean IQ is also 102) |
| Eta | A correlational technique used primarily for non-linear relationships. (Example, income and age are positively correlated until older age at which point the correlation reverses itself to some extent. |
| Extroversion | Personality style where the individual prefers outward and group activity as opposed to inward and individual activity. |
| Factor Analysis | A statistical technique used to determine the number of components in a set of data. These components are then named according to their characteristics allowing a researcher to break down information into statistical groups. |
| Factorial ANOVA | An Analysis of Variance used when there are two or more independent variables. When there are two, the ANOVA is called a Two-Way ANOVA, three independent variables would use a Three-Way ANOVA, etc. |
| Family Therapy | Treatment involving family members which seeks to change the unhealthy familial patterns and interactions. |
| Fixation | In Freud's theory of psychosexual development, the failure to complete a stage successfully which results in a continuation of that stage into later adulthood. |
| Freud, Sigmund | Dr. Freud is often referred to as the father of clinical psychology. His extensive theory of personality development (psychoanalytical theory) is the cornerstone for modern psychological thought, and consists of (1) the psychosexual stages of development, (2) the structural model of personality (id, ego, superego), and (3) levels of consciousness (conscious, subconscious, and unconscious). See Psychoanalysis. |
| Flooding | A behavioral technique used to treat phobias in which the client is presented with the feared stimulus until the associated anxiety disappears. |
| Fluid Intelligence | According to Cattell, the part of intelligence which involves the use, as opposed to the acquisition, of information. |
| Formal Operational Stage | Piaget's fourth and final stage of cognitive development where thinking becomes more abstract. |
| Framing | Presenting information either positively or negatively in order to change the influence is has on an individual or group. |
| Free Association | The psychoanalytic technique of allowing a patient to talk without direction or input in order to analyze current issues of the client. |
| Frontal Lobe | The lobe at the front of the brain associated with movement, speech, and impulsive behavior. |
| Frustration | The feelings, thoughts, and behaviors associated with not achieving a particular goal or the belief that a goal has been prematurely interrupted. |
| Frustration-Aggression Hypothesis | The theory arguing that aggression is the natural reaction to frustration. |
| Functionalism | The school of thought popular in the 19th century emphasizing conscious experiences as a precursor to behavior |
| Fundamental Attribution Error | The tendency to over estimate the internal attributes of another person's actions. |
| g | General intelligence. Typically compared to s which represents specific intelligences. G is the culmination of all possible s's. |
| GABA (Gamma-Amino Butyric Acid) | A neurotransmitter involved in the inhibition of anxiety and excitation. Too little GABA has been associated with anxiety disorders. |
| Gender Identity | The internal sense of being either male or female. Usually congruent with biological gender, but not always as in Gender Identity Disorder. |
| Gender Role | The accepted behaviors, thoughts, and emotions of a specific gender based upon the views of a particular society or culture. |
| Gender Typing | The process of developing the behaviors, thoughts, and emotions associated with a particular gender. |
| Generalization | The tendency to associate stimuli, and therefore respond similarly to, due to their closeness on some variable such as size, shape, color, or meaning. |
| Genital Stage | Freud's final stage of psychosexual development where healthy sexual development is defined as attraction to a same aged, opposite sexed peer. |
| Gestalt | German word typically translated as meaning 'whole' or 'form.' |
| Gestalt Therapy | Treatment focusing on the awareness and understanding of one's feelings. |
| Grouped Frequency Distribution | A table showing the number of occurrences for a grouping of scores. Used a lot in educational settings where a score of 90 to 100 may be grouped as an A, a score of 80 to 90 may be grouped as a B, etc. |
| Group Polarization | The tendency for members of a cohesive group to make more extreme decisions due to the lack of opposing views. |
| Group Therapy | Psychotherapy conducted with at least three or four non-related individuals who are similar in some are, such as gender, age, mental illness, or presenting problem. |
| Group Think | The tendency for members of a cohesive group to reach decisions without weighing all the facts, especially those contradicting the majority opinion. |
| Gustation | Sense of taste. |
| Habituation | The decrease in response to a stimulus due to repetition (e.g., not hearing the ticking of a clock after getting used to it) |
| Hallucination | False perception of reality (e.g., hearing voices that aren't there or seeing people who do not exist) [auditory (hearing); visual (sight); olfactory (smell); tactile (touch); and taste]. |
| Halo Effect | The tendency to assign generally positive or generally negative traits to a person after observing one specific positive or negative trait, respectively. |
| Hawthorne Effect | The phenomenon that subject behavior changes by the mere fact that they are being observed. |
| Health Psychology | The specific field in psychology concerned with psychology's impact on health, physical well being, and illness. |
| Heterosexuality | Being attracted to or aroused by members of the opposite gender. See Sexual Orientation. |
| Heuristic | A rule of thumb based on experience used to make decisions. |
| Hierarchy of Needs | Maslow's Theory of Motivation which states that we must achieve lower level needs, such as food, shelter, and safety before we can achieve higher level needs, such as belonging, esteem, and self-actualization. |
| Higher Order Conditioning | Pairing a second conditioned stimulus with the first conditioned stimulus in order to produce a second conditioned response. |
| Hippocampus | Part of the limbic system. Involved more in memory, and the transfer of information from short-term to long-term memory. |
| Humanistic Therapy | Treatment focused on increasing awareness of one's self concept. |
| Hypnosis | A deep state of relaxation where an individual is more susceptible to suggestions. |
| Hypnotherapist | A trained, and often licensed, therapist who utilizes the therapeutic technique of hypnosis as part of a treatment regimen. |
| Hypnotist | An individual, most likely unlicensed, who uses hypnosis techniques or variations of these techniques for a variety of reasons, including treatment and/or entertainment. |
| Hypothalamus | A part of the brain that controls the autonomic nervous system, and therefore maintains the body's homeostasis (controls body temperature, metabolism, and appetite. Also translates extreme emotions into physical responses. |
| Hypothesis | A prediction about the relationship between two or more variables. |
| Id | In Psychoanalytical theory, the part of the personality which contains our primitive impulses such as sex, anger, and hunger. |
| Ideal Self | Humanistic term representing the characteristics, behaviors, emotions, and thoughts to which a person aspires. |
| Illusion | Misperception of reality (e.g., the illusion of a lake in the middle of a desert). |
| Imagery | Utilizing the mind to create a mental representation of a sensory experience. |
| Inferential Statistics | The branch of statistics that focuses on describing in numerical format what might be happening or what might happen (estimation) in the future (probability). Inferential statistics required the testing of only a sample of the population. (Example: 100 students rather than all students). |
| Inhalant | Substances such as spray paint, freon, and glue that produce an intoxicating effect when inhaled. |
| Innate | Occurring without learning, inborn. |
| Insanity | A legal term representing the inability to know right from wrong or the inability to understand the consequences of one's actions. |
| Insight | The understanding of a relationship between current thoughts, feelings, and/or behaviors and where these originated or how they are maintained. |
| Internal Locus of Control | The belief that an individual has more control over life circumstances than the environment does. |
| Internal Validity | A measure of the trustworthiness of a sample of data. Internal validity looks at the subject, testing, and environment in which the data collection took place. |
| Interquartile Range | The difference between the scores (or estimated scores) at the 75th percentile and the 25th percentile. Used more than the range because it eliminates extreme scores. |
| Interval Estimation | Estimating the population statistic based on a range around a sample statistic. |
| Interval Scale | Any scale of measurement possessing magnitude and equal intervals, but not an absolute zero. |
| Lower Confidence Limit | The lower limit of a confidence interval. If prediction states that the true score falls between 80 and 90, then the lower confidence level is 80. |
| Lucid Dream | A dream in which you are aware of dreaming and are sometimes able to manipulate the dream. |
| Magnitude | Characteristic of a scale of measurement where the individual units possess the qualities of greater than, equal to, or less than. |
| Main Effect | The effect of one variable on another without any other variables or subgroups involvement. |
| Manifest Content | According to Freud, the story-like superficial content of a dream, often representing only the daily activities and little underlying unconscious material. |
| Maslow, Abraham | Humanistic Theorist most famous for the development of the Hierarchy of Needs. |
| Maturation | Changes due to the natural process of aging as determined by your genetics |
| Mean | A measure of central tendency determined by adding all scores together and dividing by the number of scores. Often referred to as the statistical average. |
| Measure of Central Tendency | An average (see Mean, Median, and/or Mode) |
| Measurement, Scales of | Categories of data based on their numerical characteristics (See Ratio, Interval, Ordinal, and Nominal Scales) |
| Minnesota Multiphasic Personality Inventory, 2nd. Edition | An Objective test utilizing 567 items which have been empirically derived to measure a variety of psychological concerns. |
| MMPI-2 | See Minnesota Multiphasic Personality Inventory, 2nd. Edition. |
| Mode | A measure of central tendency that uses the most frequently occurring score. A distribution with two or more scores that are equal and occur most frequently is called multi-modal. |
| Modeling | Learning through the imitation or observation of others. |
| Mortality | Subject drop-out in a research study. Mortality becomes a problem when a disproportionate drop out rate occurs between two or more groups (Example: 30% of males drop out of group one while only 2% of males drop out in group two, resulting in uneven groups). |
| NCE Score | A standard score that sets the mean to fifty and standard deviation to 21.06, allowing the 99th percentile to have a score of 99 and the first percentile a score of 1. |
| Negative Correlation | a correlation where one two variables tend to move in the opposite direction (example: the number of pages printed and the amount of ink left in your printer are negatively correlated. The more pages printed, the less ink you have left.) |
| Negative Skew | A curve or distribution of scores that has extreme scores below the mean that are atypical of the majority of scores. |
| Neuron | A specialized nerve cell. |
| Neurotransmitter | A chemical found in animals that plays a role in our behavior, cognitions, and emotions. |
| Nightmare | A frightening dream occurring in REM sleep. |
| Nominal Scale | Any scale that contains no magnitude. Often nominal is thought of as name only, meaning that the variables of a nominal scale can be identified but not measured. |
| Nondeclarative Memory | A subsystem within Long term memory which consists of skills we acquire through repetition and practice (e.g., dance, playing the piano, driving a car) |
| Nonparametric Test | Any statistic that is designed for ordinal or nominal data or data that is not normally distributed |
| Norepinephrine | A neurotransmitter associated with eating and alertness. Too little has been associated with depression and too much has been associated with schizophrenia. |
| Norm | An expectation based on multiple observations. |
| Normal Curve | A graphical interpretation of a population that is 'bell shaped' as it has the highest frequency in the middle and this frequency diminishes the farther you get from the center on either end. The mean, median, and mode are all equal in a perfect normal curve. |
| Normal Distribution | The scores of a sample or population that, when graphed, fall on or close to a normal curve. A normal distribution is often ideal in research because the data can then be said to have all of the characteristics of a normal curve. |
| Null Hypothesis | The hypothesis that states there is no difference between two or more sets of data. |
| Object Permanence | The understanding that objects exist even when they are not directly observed. |
| One-Way ANOVA | An Analysis of Variance used when there is only one main effect. |
| Operant Conditioning | Learning that occurs due to the manipulation of the possible consequences. |
| Optimal Level of Arousal | Theory arguing that humans are driven to increase or decrease arousal to produce a comfortable level that is not over- nor under stimulating. |
| Oral Aggressive Personality | Stemming from the Oral stage, a child who becomes fixated due to over stimulation transfers his or her unresolved oral issues into aggression and hostility. |
| Oral Receptive Personality | Stemming from the Oral stage, a child who becomes fixated due to under stimulation transfers his or her unmet oral needs into smoking, drinking, talking, biting fingernails, or sucking one's own thumb, for example. |
| Panic Attack | Period of extreme anxiety and physical symptoms such as heart palpitations, shakiness, dizziness, and racing thoughts. Initial attacks are often reported to feel like a heart attack due to the heart palpitations. A medical exam should be conducted to rule out any such condition. |
| Parallel Form Reliability | The correlation coefficient determined by comparing the scores of the two similar measuring devices (or forms of the same test) administered to the same people at one time. |
| Parameter | A summary value of a specific population characteristic (e.g., mean age, standard deviation of IQ's, median income) |
| Parasympathetic Nervous System | A subsystem of the Autonomic Nervous System (ANS) that returns the body to homeostasis. |
| Parietal Lobe | One of four lobes of the brain. Contains the Somatosensory Cortex d is therefore involved in the processing of touch, pressure, temperature, and pain. |
| Peak Experience | A life experience considered paramount due to the feeling of unity with the world. |
| Pearson Product-Moment Correlation | A correlation statistic used primarily for two sets of data that are of the ratio or interval scale. The most commonly used correlational technique. |
| Penis Envy | In Psychoanalytic Thought, the desire of girls to posses a penis and therefore have the power that being male represents. |
| Percentile Rank | Percentage of scores falling at or below a specific score. A percentile rank of 95 means that 95% of all of the scores fall at or below this point. In other words, the score is as good as or better than 95% of the scores. |
| Perception | The process of organizing and using information that is received through the senses. |
| Permissive [parents] | Parenting style consisting of very few rules and allowing children to make most decisions and control their own behavior. |
| Persuasion | The deliberate attempt to influence the thoughts, feelings or behaviors of another. |
| Phallic Personality | Stemming from the Phallic stage, a child who becomes fixated may develop a personality characterized by selfishness, impulsivity, and a lack of or reduced ability to feel empathy. |
| Phallic Stage | Freud's third stage of psychosexual development where the primary sexual focus is on symbolism of the genitals. |
| Phi Correlation | A correlational technique used when both variables are binary (Example true/false, yes/no, or on/off) |
| Phi Phenomenon | The perception of motion based on two or more stationary objects (e.g., the perception of chaser lights brought about by different lights blinking at different times). |
| Phobia | An intense fear of a specific object or situation. Most of us consider ourselves to have phobias, but to be diagnosable, the fear must significantly restrict our way of life. |
| Placebo | A treatment condition used to control for the placebo effect where the treatment has no real effect on its own. |
| Placebo Effect | The phenomenon in research where the subject's beliefs about the outcome can significantly effect the outcome without any other intervention. |
| Plasticity | The ability of the brain, especially in our younger years to compensate for damage. |
| Population | The entire group to which research is hoping to generalize (e.g., males, adults, U.S. citizens). |
| Population Mean | The true mean of the entire population often estimated using the sample mean. Abbreviated with the lowercase Greek letter mu. (m) |
| Population Standard Deviation | The true standard deviation of the population often estimated by using the sample standard deviation. Often abbreviated with the lowercase Greek letter sigma. (s) |
| Positive Correlation | A correlation where as one variable increases, the other also increases, or as one decreases so does the other. Both variables move in the same direction. |
| Positive Reinforcement | Something positive provided after a response in order to increase the probability of that response occurring in the future. |
| Probability Sample | Also called representative samples, a probability sample consists of characteristics that are close to the population that they represent. |
| Projection | In Psychoanalytic Theory, the defense mechanism whereby we transfer or project our feelings about one person onto another. |
| Projective Techniques | A generic term for the psychological procedures used to measure personality which rely on ambiguous stimuli. |
| Psychiatrist | A medical doctor with training in mental illness. |
| Psychoanalysis | Developed by Sigmund Freud, this type of therapy is known for long term treatment, typically several times per week, where the unresolved issues from the individual's childhood are analyzed and resolved. These issues are considered to be primarily unconscious in nature and are kept from consciousness through a complex defense system. |
| Psychoanalytic Theory | Theory developed by Freud consisting of the structural model of personality, topographical model of personality, defense mechanisms, drives, and the psychosexual stages of development. The primary driving force behind the theory is the id, ego and superego and the division of consciousness into the conscious mind, the pre/subconscious, and the unconscious. |
| Psychodynamic Therapy | A modern adaptation of psychoanalytic therapy which has made sometimes minor and sometimes major changes to Freud's original theories. |
| Psychotherapy | The treatment of mental illness or related issues based on psychological theory. |
| Psychology | The study of emotion, cognition, and behavior, and their interaction. |
| Psychosis | Break from reality, usually identified by hallucinations, delusions, and/or disorientation. |
| Random Sample | A group of subjects representing the population who are selected through chance. |
| Range | the difference between the highest and lowest score in a distribution (often 1 is added to the result when computing statistics to allow for the 0.5 on either end lost due to rounding). |
| Rank-Ordered Array | A table consisting of data in order of highest to lowest or lowest to highest where each data is given a numbered rank depicting it's difference from the highest or lowest score |
| Ratio Scale | Any scale of measurement possessing magnitude, equal intervals, and an absolute zero |
| Rational Emotive Therapy | A Cognitive Therapy based on Albert Ellis' theory that cognitions control our emotions and behaviors; therefore, changing the way we think about things will affect the way we feel and the way we behave. |
| Representative Sample | A sample or subgroup of the population that possesses the same characteristics of the population |
| Representativeness Heuristic | A rule of thumb where similarity to a prototype or similar situation dictates a decision. |
| Repression | In Psychoanalytic Theory, the defense mechanism whereby our thoughts are pulled out of our consciousness and into our unconscious. |
| Resistance | In psychoanalysis, the client's refusal to participate in a therapeutic intervention due to underlying issues unrelated to the intervention. |
| Response Prevention | A therapeutic technique where stimuli is presented to the client but the client is not permitted to exercise his or her typical response. Used for the treatment of phobias, obsessive compulsive disorder and other anxiety disorders. |
| Reticular Formation (Reticular Activating System) | Part of the brain stem involved in arousal and attention, sleep and wakefulness, and control of reflexes. |
| Retinal Disparity | The binocular cue to distance referring to the distance between the two images sent to the brain by our eyes. The farther apart these images, the closer the object. |
| Retrieval | The process of bringing material out of long term memory and into consciousness. |
| Retroactive Interference | Interference in memory created by later learning. |
| Reversal Design | Any single subject design that includes the removal of treatment to determine if the subject reverts to baseline (ex. ABA, ABAB) |
| Sensory Adaptation | The reduced ability to sense a stimulus after prolonged exposure. |
| Sensory Memory | The brief storage of information brought in through the senses; typically only lasts up to a few seconds. |
| Separation Anxiety | Distress caused by the absence of an infant's primary caregiver |
| Serotonin | A neurotransmitter involved in mood, sleep, appetite, and impulsive and aggressive behavior. Too little has been associated with depression and some anxiety disorders (e.g., obsessive-compulsive disorder). Many antidepressants attempt to reduce the amount of serotonin that is taken back (reuptake) into the sending neuron (e.g., Serotonin Reuptake Inhibitors [SRI]). |
| Sexual Orientation | A feeling of attractedness or arousal associated with a particular gender. Sexual behavior can be a result of this but does not necessarily define a person's orientation. |
| Stage Theory | The idea that an individual must pass through one stage of development before he or she can reach the next stage. |
| Standard Deviation | A measure of spread within a distribution (the square root of the variance). The most popular and most reliable measure of variability but the more skewed a distribution, the more error there will be in the standard deviation because of its reliance on the mean. |
| Standard Error of Measurement | a statistical procedure used to determine the amount of error of any measurement device |
| Standard Error of the Mean | An estimation of the unaccounted for error within a mean. If the mean is 10 and the standard error of the mean is 2, then the true score is likely to fall somewhere between 8 and 12 or 10 +/- 2. |
| Standardization | The process of making a test or procedure the same for everyone so that results can be compared to each other. |
| Standard Score | A score derived by transforming the data based on the standard deviation. Standard scores can then be compared to one another on face value. (See z-score, T-score, NCE score, stanines, and Wechsler's Deviation IQ Score) |
| Stanine | A standard score that literally means Standard Nine, stanines have a mean of five and a standard deviation of approximately two. Stanines 2 through 8 are exactly 1/2 standard deviations and stanines one and nine or open ended. |
| Statistic | An observed characteristic of a sample (e.g., 20% improvement rate, range of IQ's) |
| State | A temporary internal characteristic (e.g., depressed, angry) |
| State Dependent Memory | The theory that information learned in a particular state of mind (e.g., depressed, happy, somber) is more easily recalled when in that same state of mind. |
| Stem and Leaf Display | A multiple column table depicting the individual digits of the scores. A score of 95 would have a stem of 9 and a leaf of 5, a score of 62 would have a stem of 6 and a leaf of 2. If a particular stem has more than one leaf, such as the scores 54, 58, and 51, the stem of 5 has three leaves, in this case 458. |
| Stimulus | Anything in the environment to which one responds. |
| Stimulus Discrimination | The ability to tell the difference and therefore not respond to similar stimuli. |
| Stimulus Generalization | The response to new stimuli due its similarity to the original stimuli. |
| Storage | The process of saving information in long term memory |
| Syllogism | Aristotle's theory of reasoning where two true statements are followed by a single logical conclusion. |
| Sympathetic Nervous System (SNS) | Part of the Autonomic Nervous System responsible for the fight or flight phenomenon and which plays a role (along with the Parasympathetic Nervous System) in maintaining the body's homeostasis. |
| Synapse | The space between the axon of one neuron and the dendrites of another through which neurotransmitters travel. |
| Systematic Desensitization | A treatment technique where the client is exposed to gradually increasing anxiety provoking stimuli while relaxing; the goal is for the client to eventually confront a phobia or fear without the previously associated anxiety. |
| T-Score | A standard score that sets the mean to fifty and standard deviation to ten. Used on a number of tests including the MMPI. |
| Test-Retest Reliability | The correlation coefficient determined by comparing the scores of the same measuring device administered to the same people on two different occasions. |
| Tetrachoric Correlation | A correlational technique used to estimate the Pearson-Product correlation of two continuous variables that have been dichotomized (Example: age is continuous, but when it is split into two groups, such as over 40 and under 40, it becomes dichotomous). |
| Thalamus | Considered the central switching station of the brain because all of the body's senses (except the olfactory senses) pass through this before being relayed to the brain. |
| Thematic Apperception Test (TAT) | A subjective personality test where ambiguous pictures are shown to a subject and they are asked to tell a story related to them. |
| Theory | A general idea about the relationship of two or more variables. |
| True Score | the amount of the observed score that truly represents what you are intending to measure. |
| Two-Way ANOVA | An Analysis of Variance used when there are two independent variables. |
| Type A Personality | A theory used to describe a person with a significant number of traits focused on urgency, impatience, success, and excessive competition. |
| Type B Personality | A theory used to describe person with a significant number of traits focused on relaxation, lack of urgency, and normal or reduced competition. |
| Type I Error | The error that is committed when a true null hypothesis is rejected erroneously. The probability of a Type I Error is abbreviated with the lowercase Greek letter alpha. |
| Upper Confidence Level | The upper limit of a confidence interval. If prediction states that the true score falls between 80 and 90, then the upper confidence level is 90. |
| Validity | Statistical technique used to determine if a test is actually measuring what it is intended to measure. |
| Variability | The degree to which a distribution of scores vary around the mean. High variability means scores are spread wider apart and low variability means scores are relatively close together. Typical ways of determining variability are the range, interquartile range, semi-interquartile range, variance, and standard deviation. |
| Variable | Any factor which has the potential to influence another factor in a research study. |
| Variable Interval Schedule | A schedule in which the reinforcement is presented after a varying amount of time. |
| Wechsler Adult Intelligence Scale, 3rd Ed | An objective measure of intelligence. The Stanford-Binet test is also used, has very similar validity, but is not as popular. |
| Wernicke's Aphasia | Aphasia resulting from damage to the Wernicke's area of the frontal lobe. Affects written and spoken language. |
| Yerkes-Dodson Law | Theory arguing that for performance to be optimal, the amount of arousal required must be optimized. Too much or too little stimulation will result in a poorer performance. |
| Zero Correlation | the absence of a relationship between two or more variables as determined by a correlational statistic. Often abbreviated as 'r=0.' |
| z-score | a standard score that sets the mean to zero and standard deviation to one. |
