Form Perception: The sensory discrimination of a pattern shape or outline.Rorschach Test: A projective test used to evaluate a broad range of personality variables including pathology of thought and perception. The subject's responses to inkblot prints are scored along with subjective interpretation by the test administrator.Reality Testing: The individual's objective evaluation of the external world and the ability to differentiate adequately between it and the internal world; considered to be a primary ego function.Psychophysics: The science dealing with the correlation of the physical characteristics of a stimulus, e.g., frequency or intensity, with the response to the stimulus, in order to assess the psychologic factors involved in the relationship.Perception: The process by which the nature and meaning of sensory stimuli are recognized and interpreted.Pattern Recognition, Visual: Mental process to visually perceive a critical number of facts (the pattern), such as characters, shapes, displays, or designs.Photic Stimulation: Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.Visual Perception: The selecting and organizing of visual stimuli based on the individual's past experience.Motion Perception: The real or apparent movement of objects through the visual field.Social Perception: The perceiving of attributes, characteristics, and behaviors of one's associates or social groups.Speech Perception: The process whereby an utterance is decoded into a representation in terms of linguistic units (sequences of phonetic segments which combine to form lexical and grammatical morphemes).Depth Perception: Perception of three-dimensionality.Auditory Perception: The process whereby auditory stimuli are selected, organized, and interpreted by the organism.Pain Perception: The process by which PAIN is recognized and interpreted by the brain.Time Perception: The ability to estimate periods of time lapsed or duration of time.Pitch Perception: A dimension of auditory sensation varying with cycles per second of the sound stimulus.Taste Perception: The process by which the nature and meaning of gustatory stimuli are recognized and interpreted by the brain. The four basic classes of taste perception are salty, sweet, bitter, and sour.Space Perception: The awareness of the spatial properties of objects; includes physical space.Touch Perception: The process by which the nature and meaning of tactile stimuli are recognized and interpreted by the brain, such as realizing the characteristics or name of an object being touched.Size Perception: The sensory interpretation of the dimensions of objects.Color Perception: Mental processing of chromatic signals (COLOR VISION) from the eye by the VISUAL CORTEX where they are converted into symbolic representations. Color perception involves numerous neurons, and is influenced not only by the distribution of wavelengths from the viewed object, but also by its background color and brightness contrast at its boundary.Olfactory Perception: The process by which the nature and meaning of olfactory stimuli, such as odors, are recognized and interpreted by the brain.Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.Health Knowledge, Attitudes, Practice: Knowledge, attitudes, and associated behaviors which pertain to health-related topics such as PATHOLOGIC PROCESSES or diseases, their prevention, and treatment. This term refers to non-health workers and health workers (HEALTH PERSONNEL).Attitude to Health: Public attitudes toward health, disease, and the medical care system.Attitude of Health Personnel: Attitudes of personnel toward their patients, other professionals, toward the medical care system, etc.Weight Perception: Recognition and discrimination of the heaviness of a lifted object.Illusions: The misinterpretation of a real external, sensory experience.Sensory Thresholds: The minimum amount of stimulus energy necessary to elicit a sensory response.Discrimination (Psychology): Differential response to different stimuli.Optical Illusions: An illusion of vision usually affecting spatial relations.Music: Sound that expresses emotion through rhythm, melody, and harmony.Attitude: An enduring, learned predisposition to behave in a consistent way toward a given class of objects, or a persistent mental and/or neural state of readiness to react to a certain class of objects, not as they are but as they are conceived to be.Focus Groups: A method of data collection and a QUALITATIVE RESEARCH tool in which a small group of individuals are brought together and allowed to interact in a discussion of their opinions about topics, issues, or questions.Cues: Signals for an action; that specific portion of a perceptual field or pattern of stimuli to which a subject has learned to respond.Orientation: Awareness of oneself in relation to time, place and person.Acoustic Stimulation: Use of sound to elicit a response in the nervous system.