ELSEVIER''''S DICTIONARY OF PSYCHOLOGICAL THEORIES phần 10 potx

611 cally in perception). See also CARPEN- TERED-WORLD HYPOTHESIS; CON- SCIOUSNESS, PHENOMENON OF; CON- STRUCTIVIST THEORY OF PERCEP- TION; EMPIRICIST VERSUS NATIVIST THEORIES; PERCEPTION (I. GENERAL), THEORIES OF; PERCEPTION (II. COM- PARATIVE APPRAISAL), THEORIES OF. REFERENCES Helmholtz, H. von (1856-1866). Physiological optics. Leipzig: Voss. Wundt, W. (1862). Beitrage zur theorie der sinneswahrnehmung. Leipzig: Wun- ter’sck. Freud, S. (1915). The unconscious. In The standard edition of the complete psychological works of Sigmund Freud. London: Hogarth Press. Hochberg, J. (1994). Unconscious inference. In R. J. Corsini (Ed.), Encyclopedia of psychology. New York: Wiley. Chalmers, D. (1996). The conscious mind: In search of a fundamental theory. New York: Oxford University Press. UNCONSCIOUS MEMORY/UNCON- SCIOUSNESS THEORY. See FORGET- TING/MEMORY, THEORIES OF; FREUD’S THEORY OF PERSONALITY; UNCON- SCIOUS INFERENCE, DOCTRINE OF. UNDERSTIMULATION THEORY. See PSYCHOPATHOLGY, THEORIES OF. UNDULATORY THEORY. See VISION/ SIGHT, THEORIES OF. UNIFIED THEORY OF COGNITION. See PROBLEM-SOLVING AND CREATIVITY STAGE THEORIES. UNIFIED THEORY OF SOCIAL PSY- CHOLOGY. See INFORMATION INTE- GRATION THEORY. UNIFORMITY OF NATURE THEORY. See FINAL THEORY. UNIFYING THEORY OF DEVELOP- MENT. See DEVELOPMENTAL THEORY. UNILINEAL/UNILINEAR THEORY. See RECAPITULATION THEORY/LAW. UNIT HYPOTHESIS. See GENERALIZA- TION, PRINCIPLES OF. UNIVERSALISM, DOCTRINE OF. See MIND/MENTAL STATES, THEORIES OF. UNIVERSALISTIC THEORIES. See WORK/CAREER/OCCUPATION, THEO- RIES OF. UNIVERSAL LAW OF GENERALIZA- TION. The American psychologist/cognitive scientist Roger N. Shepard (1929- ) proposed a universal law of generalization for psycho- logical science that attempts to advance a principle in psychology that is comparable in generality to the English physicist and mathematician Sir Isaac Newton’s (1642- 1727) universal law of gravitation in physics. The new law is based on the assumption that because any object or situation experienced by an individual is unlikely to recur in exactly the same form and context, psychology’s first general law should be a law of generalization. Historically, learning theorists supposed that a principle of conditioning (via the mechanisms of reinforcement and/or contiguity) could be the primary principle, and where what is learned then generalizes to new situations (left open for later formulation) could be a secon- dary principle. Over 2,000 years ago, the Greek philosopher Aristotle (384-322 B.C.) recognized - via his principle of association by resemblance - that similarity is fundamen- tal to mental processes, but it was not until the beginning and middle of the 20 th century that experimental investigations were conducted on the issue of generalization/similarity of stimuli - first by Ivan Pavlov in the 1920s; then by Norman Guttman, H. I. Kalish, and Roger N. Shepard in the 1950s; cf., Mostofsky (1965). Shepard suggests that humans general- ize from one situation to another not because they cannot tell the difference between the two situations, but because they judge that the situations are likely to belong to a set of situa- tions having the same consequences. Gener- alization - that arises from uncertainty about the distribution of consequential stimuli in 612 “psychological space” - is to be distinguished from failure of discrimination - that arises from uncertainty about the relative locations of individual stimuli in that space. Accord- ingly, in his universal law of generalization for psychological science, Shepard posits the notion of a “psychological space” for any set of stimuli by determining metric distances between the stimuli such that the probability that a response learned to any stimulus will generalize to any other is an invariant mono- tonic function of the distance between them. This probability of generalization, to a good approximation, decays exponentially with this distance, and does so in accordance with one of two metrics, depending on the relation be- tween the dimensions along which the stimuli vary. Shepard asserts that these empirical regularities are mathematically derivable from universal principles of natural phenomena and probabilistic geometry that may – via evolu- tionary internalization - tend to govern the behaviors of all sentient organisms. Shepard suggests that psychological science undoubt- edly has lagged behind physical science by at least 300 years and, just as likely, predictions of behavior may never attain the precision for animate bodies/entities that it has for celestial bodies. However, psychology inherently may not be limited merely to the descriptive char- acterization of the behaviors of particular terrestrial species, but possibly - behind the diverse behaviors of humans and animals, as behind the various motions of planets and stars - one may eventually discern the opera- tion of universal laws. See also ASSOCIA- TION, LAWS/PRINCIPLES OF; GENER- ALIZATION, PRINCIPLES OF. REFERENCES Newton, I. (1687). Philosophiae naturalis principia mathematica. London: Royal Society. Mostofsky, D. I. (Ed.) (1965). Stimulus gen- eralization. Stanford, CA: Stanford University Press. Shepard, R. N. (1987). Toward a universal law of generalization for psycho- logical science. Science, 237, 1317- 1323. UNIVERSAL LAW OF GRAVITATION. See UNIVERSAL LAW OF GENERALIZA- TION. UNIVERSAL MODEL OF HUMAN EMOTIONS. The American neurologist/ physician Antonio R. Damasio (1994) devel- oped a universal model of human emotions that is based on a rejection of the Cartesian mind-body dualism, and is founded on neuro- psychological studies and experiments. The model begins with the assumption that human knowledge consists of dispositional represen- tations stored in the brain (where “thought” is the process by which such representations are ordered and manipulated). One of the repre- sentations is of the body as a whole and is based on information from the endocrine and peripheral nervous systems. In his model, Damasio defines emotion as the combination of a mental evaluative process (simple or complex) with dispositional responses to that process, resulting in an emotional body state - but also toward the brain itself (e.g., via neu- rotransmitter nuclei in the brain stem). In dis- tinguishing “emotions” from “feelings,” Damasio states that the brain is continually monitoring changes in the body, and suggests that people “feel” an emotion when they ex- perience such changes in juxtaposition to the mental images that initiated the cycle. The model distinguishes, also, between “primary emotions” (innate) and “secondary emotions” (feelings allowing one to form systematic connections between categories of objects and situations). Damasio suggests that the neuro- logical mechanisms of emotion and feeling evolved in humans in order to create strong biases to situationally-appropriate behaviors that do not require conscious thought; he ar- gues that the time-consuming process of ra- tional thought may decrease one’s chances of survival in situations that require instant deci- sions. See also EMOTIONS, THEORIES/ LAWS OF; MIND-BODY THEORIES. REFERENCE Damasio, A. R. (1994). Descartes’ error: Emotion, reason, and the human brain. New York: Putnam. 613 UNLEARNING HYPOTHESIS. See IN- TERFERENCE THEORIES. UNREADINESS, LAW OF. See READI- NESS, LAW OF. UNREALISTIC OPTIMISM EFFECT. This phenomenon, and its related aspects, studied by the American psychologists Freder- ick Hansen Lund (1894-1965), Albert Hadley Cantril (1906-1969), and Neil David Weinstein (1945- ), among others, refers to a judgmental bias in humans that tends to influ- ence their subjective estimates of the likeli- hood of certain future events in their own lives as compared to others, especially their peers. For example, the unrealistic optimism effect demonstrates that people overestimate the likelihood in their lives of positive/desirable events (e.g., the possibility of their living to be older than 80 years of age), and underestimate the likelihood in their lives of negative/unde- sirable events (e.g., the possibility of having a heart attack before they are 50 years old). Studies on this issue indicate that cognitive, motivational, and social factors such as degree of desirability, perceived probability, personal experience, ego-centrism, perceived control- lability, and stereotype salience all tend to affect the amount of optimistic bias evoked by different possible events in people’s lives. See also DECISION-MAKING THEORIES; OVERCONFIDENCE EFFECT. REFERENCES Lund, F. H. (1925). The psychology of belief. Journal of Abnormal and Social Psychology, 20, 63-81, 174-195. Cantril, A. H. (1938). The predicton of social events. Journal of Abnormal and Social Psychology, 33, 364-389. Weinstein, N. D. (1980). Unrealistic optimism about future life events. Journal of Personality and Social Psychology, 39, 806-820. UPWARD PYGMALION EFFECT. See PYGMALION EFFECT. URNING THEORY. See SEXUAL ORIEN- TATION THEORIES. USE-DISUSE PRINCIPLE. See LA- MARCK’S THEORY. USE, LAW OF. This principle is one of the corollaries of the American psychologist Ed- ward Lee Thorndike’s (1874-1949) law of exercise, which states that behaviors, stimu- lus-response connections, and functions that are exercised, rehearsed, or practiced are strengthened as compared to those behaviors, bonds, or functions that are not used. Some early writers held that the repeated use of a stimulus-response connection unit (neurons) bring about certain synaptic changes that made the passage of the nerve impulse more rapid in the future. For example, in 1926 A. Gates called this native capacity of nervous structure modifiability the law of modification by exercise or, more simply, the law of use [cf., the use/disuse, use-inheritance theory advanced by the French naturalist/evolutionist Jean-Baptiste Pierre Antoine de Monet La- marck (1744-1829), which holds that the structural or functional changes in organs brought about by their use or disuse are passed onto the progeny). The notion of a physiologi- cal change in nervous structure during the practice (use) of stimulus-response connec- tions anticipated the Canadian psychologist Donald Olding Hebb’s (1904-1985) later con- ceptualizations in perception and learning of cell assembly and phase sequence, where groups of neurons are functionally interrelated and organized into a complex “closed circuit” created by repeated stimulation of those units. See also DISUSE, LAW/THEORY OF; EF- FECT, LAW OF; EXERCISE, LAW OF; FREQUENCY, LAW OF; HEBB’S THEORY OF PERCEPTUAL LEARNING; LA- MARCK’S THEORY. REFERENCES Thorndike, E. L. (1898). Animal intelligence. New York: Macmillan. Gates, A. (1926). Elementary psychology. New York: Macmillan. Trowbridge, M., & Cason, H. (1932). An ex- perimental study of Thorndike’s theory of learning. Journal of Gen- eral Psychology, 7, 245-258. Hebb, D. O. (1947). Organization of behavior. New York: Wiley. 614 Hebb, D. O. (1972). Textbook of psychology. Philadelphia, PA: Saunders. US-VERSUS-THEM EFFECT. See IN- GROUP BIAS THEORIES; PREJUDICE, THEORIES OF. UTERINE THEORY. See PSYCHOPA- THOLOGY, THEORIES OF. UTILITARIANISM, THEORY OF. See REFLEX ARC THEORY/CONCEPT. UTILITY THEORY. See DECISION- MAKING THEORIES; ELICITED OBSER- VING RATE HYPOTHESIS; EXPECTED UTILITY THEORY; HEDONISM, THE- ORY/LAW OF; LOGAN’S MICROMOLAR THEORY. UZNADZE/DELBOEUF ILLUSIONS. See APPENDIX A. 615 V VALENCE-EXPECTANCY THEORY. See WORK/CAREER/OCCUPATION, THEO- RIES OF. VALENCE-INSTRUMENTALITY-EX- PECTANCY THEORY. See WORK/CAR- EER/OCCUPATION, THEORIES OF. VALIDITY/RELIABILITY. See NOMO- LOGICAL NETWORK THEORY. VALUE THEORY. See DECISION-MAK- ING THEORIES; MEINONG’S THEORIES. VANDENBERGH EFFECT. See OLFAC- TION/SMELL, THEORIES OF. VASCULAR THEORY. See NAFE’S THEORY OF CUTANEOUS SENSITIVITY. VEATCH’S THEORY OF HUMOR. This humor theory, proposed by Thomas C. Veatch (1998), states that humor is characterized fully by certain conditions that individually are necessary, and are jointly sufficient, for the humor experience to occur. The conditions of Veatch’s theory of humor involve a subjective state of apparent emotional absurdity where the perceived situation is viewed as normal and where, simultaneously, some affective commitment of the perceiver (to the way something in the situation ought to be) is vali- dated. Thus, according to this approach, hu- mor occurs when one views a situation simul- taneously as being normal, as well as consti- tuting a violation of the “subjective moral order” where such an order is defined as the set of principles to which the person both has an affective commitment and a belief that he or she ought to hold those principles. Veatch explores the logical properties and empirical consequences of his theory, reviews the widely-recognized aspects and features of humor (e.g., incongruity, surprise, aggression, emotional transformation), suggests practical applications of his theory, and accounts for a wide variety of biological, social-communica- tional, and other categories/classes of humor- related phenomena. See also HUMOR, THE- ORIES OF; INCONGRUITY/INCONSIS- TENCY THEORIES OF HUMOR; SUR- PRISE THEORIES OF HUMOR. REFERENCE Veatch, T. C. (1998). A theory of humor. Hu- mor: International Journal of Hu- mor Research, 11, 161-215. VENABLE’S COLOR VISION THEORY. See COLOR VISION, THEORIES/LAWS OF. VENTRILOQUISM EFFECT. See AP- PENDIX A. VERBAL CONTEXT EFFECT. See COMMUNICATION THEORY. VERBAL DEPRIVATION HYPOTHESIS. See CHOMSKY’S PSYCHOLINGUISTIC THEORY. VERBAL LOOP HYPOTHESIS. See CHOMSKY’S PSYCHOLINGUISTIC THE- ORY. VERBAL TRANSFORMATION EFFECT. See APPENDIX A. VIBRATION/VIBRATIONAL THEORY. See OLFACTION/SMELL, THEORIES OF. VIBRATORY THEORY OF INHERIT- ANCE. See MENDEL’S LAWS/PRIN- CIPLES. VICARIOUS BRAIN PROCESS HY- POTHESIS. See LASHLEY’S THEORY. VICTIM PRECIPITATION HYPOTHE- SIS. See LOMBROSIAN THEORY. VIERORDT’S LAW OF TIME ESTIMA- TION. See VIERORDT’S LAWS. VIERORDT’S LAWS. There are two sepa- rate usages or versions subsumed under the same eponymic principle called Vierordt’s law, both of which are attributable to the 616 German physiologist Karl von Vierordt (1818- 1884). One usage is related to the study of sensory thresholds, and the other usage refers to the area of time perception. In the first case, Vierordt’s law is the proposition that the more moveable a part of the body is, the lower is the two-point threshold of the skin over it. Thus, the two-point threshold decreases (i.e., increased tactile acuity) as one goes from the acromion/shoulder blade to the tips of the fingers. In other terms, Vierordt’s law of out- ward mobility in the area of sensory psychol- ogy states that tactile acuity increases with increased mobility of body members. How- ever, although Vierordt’s outward mobility law appears to be true, generally, for the upper extremity, it is not as clearly applicable to various other body areas (cf., Greenspan & Bolanowski, 1996). In the second case, Vierordt’s law of time estimation is the princi- ple that short temporal intervals tend to be overestimated and long temporal intervals tend to be underestimated. Also, in this con- text of time perception/estimation, the concept of the in-difference interval is defined as the intermediate length of time that is neither underestimated nor overestimated. Based on this early general law of time estimation by Vierordt in the late 1800s, subsequent re- search in the area of the psychology of time has determined that the overestimation of short durations and the underestimation of long ones is as valid for “filled” dura- tions/intervals as for “empty” dura- tions/intervals. Thus, in turn, and ground-ed in Vierordt’s law of time estimation, psycholo- gists today study the effect of the different forms of “filling” a temporal interval (ranging from the use of short, discrete auditory tones to long, more continuous and meaningful nar- ratives/events/materials) on one’s perceived duration and estimation of time. See also FRAISSE’S THEORY OF TIME; GUY- AU’S THEORY OF TIME; SOMESTHESIS, THEORIES OF; TIME, THEORIES OF. REFERENCES Vierordt, K. von (1868). Der zeitsinn nach versuchen. Tubingen, Germany: H. Laupp. Vierordt, K. von (1870). Abhangigkeit der ausbildung des raumsinnes der haut von den beweglichkeit der korpert- heile. Zeitschrift fur Biologie, 6, 53- 72. Greenspan, J. D., & Bolanowski, S. J. (1996). The psychophysics of tactile percep- tion and its peripheral physiological basis. In L. Kruger (Ed.), Pain and touch. San Diego, CA: Academic Press. VIGILANCE, THEORIES OF. = sustained attention theories. In general, theories of vigi- lance refer to the systematic accounts of how observers maintain their focus of attention (i.e., the selective aspects of perception that function to help an organism focus on certain features of the environment to the exclusion of other features) and remain alert to stimuli over prolonged periods of time [i.e., sustained at- tention; cf., the law of prior entry - the princi- ple that if a participant is attending to one of two possible stimuli and, if they occur simul- taneously, the one to which he/she is attending tends to be perceived as having occurred be- fore the other; in social/personality psychol- ogy, this is called the prior entry effect where the first impression(s) one has of another per- son tend to be the dominate one(s) and are not easily changed by further acquaintance; cf., also, laws of attention (Woodworth, 1921): selection - of two or more inconsistent re- sponses to the same situation, only one is made at the same time; advantage - one of the alternative responses has an initial advantage over the others due to such factors as intensity and change in the stimulus, or to habits of reaction; shifting - the response that has the initial advantage loses its advantage shortly and an alternative response is made, provided the situation remains the same (cf., the law of shifting, proposed by the American psycholo- gist Edward Lee Thorndike, which states that it is relatively easy to elicit a response that an organism is capable of performing in any situation - and to which it is sensitive - and, thereby, form an association between the re- sponse and the features of that situation); ten- dency - a predisposition when aroused to ac- tivity facilitates responses that are in its line and inhibits others; and combination - a single response may be made to two or more stimuli, and two or more stimuli may arouse a single joint response]. The various specific theories 617 and models of vigilance attempt to deal with certain common questions in an observer’s behavior during a vigilance task: How is back- ground information stored? How are decisions made during observation? and How do neural attention units function? A sampling of the vigilance theories and some of their major tenets are: expectancy theory - observers act as “temporal averaging instruments” who form expectancies as to the approximate time course of critical signal appearances on the basis of samples of signal input; readiness to detect a signal is assumed to be positively related to level of expectancy; elicited observ- ing rate hypothesis - the observer constantly makes sequential decisions about whether or not to emit observing responses toward the display that is monitored; detection failures occur when the participant does not emit the observing responses due to fatigue or low motivation or does so in an imperfect fashion; signal detection theory - the decrement func- tion typically found in a vigilance task reflects a shift to a more conservative response crite- rion and decision process, rather than a de- cline in alertness or perceptual sensitivity to signals; activation/arousal theory - instead of a “cognitive” appraisal of vigilance, this ap- proach emphasizes a neurophysiological ex- planation whereby sensory input has two gen- eral functions: to convey information about the environment and to “tone up” the brain with a background of diffuse activity that helps cortical transmission via increased alert- ness; this orientation suggests that the mo- notonous aspects of vigilance tasks reduce the level of nonspecific activity that is necessary to maintain continued alertness and, conse- quently, lead to a decline in the efficiency of signal detection; and habituation theory - habituation is a lessening of neural respon- siveness due to repeated stimulation and is an “active process of inhibition;” this approach argues that the degree of neural habituation in a given task is directly related to the frequency of stimulus presentation so that with the de- velopment of habituation the observer’s abil- ity to discriminate critical signals is degraded, attention to the task becomes increasingly more difficult, and performance declines over a period of time; this theory holds that ha- bituation accumulates more rapidly at fast, than at slow, rates and results in a decline in performance at fast stimulus/event rates. The current status of vigilance theories is that each model focuses on a somewhat different aspect of the sustained attention situation, even though many theories can account for similar data. To date, the task remains of synthesizing the various theoretical positions of vigilance into a unified framework where stronger “law- ful” cause-effect statements may be provided. See also ACTIVATION/AROUSAL THE- ORY; ATTENTION, LAWS/PRINCIPLES OF; ELICITED OBSERVING RATE HY- POTHESIS; HABITUATION, PRINCIPLE/ LAW OF; IMPRESSION FORMATION, THEORIES OF; REINFORCEMENT, THORNDIKE’S THEORY OF; SIGNAL DETECTION THEORY. REFERENCES Woodworth, R. S. (1921). Psychology: A study of mental life. New York: Holt. Deese, J. (1955). Some problems in the theory of vigilance. Psychological Review, 62, 359-368. Baker, C. (1963). Further toward a theory of vigilance. In D. Buckner & J. McGrath (Eds.), Vigilance: A sym- posium. New York: McGraw-Hill. Davies, D., & Tune, G. (1969). Human vigi- lance performance. New York: American Elsevier. Mackworth, J. (1969). Vigilance and habitua- tion. Baltimore: Penguin Books. Stroh, C. (1971). Vigilance: The problem of sustained attention. New York: Per- gamon. Mackie, R. (Ed.) (1977). Vigilance: Theory, operational performance, and phys- iological correlates. New York: Plenum. Parasuraman, R., & Davies, D. (1989). Varie- ties of attention. Orlando, FL: Aca- demic Press. VIRAL HYPOTHESIS OF SCHIZO- PHRENIA. See SCHIZOPHRENIA, THEO- RIES OF. VIRTUAL SELF. See SELF-CONCEPT THEORY. 618 VISION/SIGHT, THEORIES OF. One of the earliest theories that attempted to describe a mechanism for human vision was proposed by the Greek mathematician/mystic Pythagor- as (c. 582-507 B.C.). He asserted that rays of light sprang from the eyes themselves, much like twin spotlights; somehow, the light strik- ing objects in front of the observer triggered a reaction in the eye, and vision was the result. However, by the 15 th century, Pythagoras’ theory was reversed, where the eyes were considered the receivers, not senders, of light. By that time, some of the greatest scientists of the say began to investigate the question of light’s influence on the eye. For example, Leonardo da Vinci (1452-1519) made detailed drawings of the eye’s anatomy; Johannes Ke- pler (1571-1630) formulated the basic laws of light refraction, which explained how light rays can be bent as they travel from one me- dium to another; and Rene Descartes (1596- 1650) conducted studies concerning the appli- cation of these refraction laws to the structural features of the eye, which led to a basic under- standing of how the eye focused incoming light [cf., Maxwellian view - named after the Scottish physicist James Clerk Maxwell (1831-1879), refers to the elimination of light fluctuations entering the eye due to pupil size fluctuations by concentrating light coming off an object by the use of a spherical, or “fish- eye,” lens to focus light in the pupil’s plane]. By 1666, Sir Isaac Newton’s (1642-1727) experiments on the composition of light itself was the formal beginning of inquiries into the physical nature of light as well as inquiries into the way the eye interprets color phenom- ena [cf., the inverse square law - the principle that the intensity of a stimulus that reaches the receptor from a distant source varies inversely as the square of the distance of the source from the receptor (Note: In the context of inferential statistics, the inverse square law is the principle that the sampling error tends to be inversely proportional to the square root of the sample size); the law of illumination - the principle that the illumination upon a surface varies directly as the luminous intensity of the light source, inversely as the square of its distance, and directly as the cosine of the an- gle made by the light rays with the perpen- dicular to the surface; and the Arago phe- nomenon - named after the French astronomer and physicist Francois Arago (1786-1853), is the relative insensitivity to light of the very center of the visual field at very low levels of illumination]. According to modern vision theory, the stimulus for the sensory modality of vision/sight is electromagnetic radiation (light) between approximately 380 and 740 nanometers (nm, where 1 nm = 1 billionth of a meter), and where the initial processing of visual information is the receptor system con- sisting of photosensitive cells (rods and cones) in the retina of the eye. Vision is the process of transforming (“transducing”) physical light energy into biological neural impulses that can then be interpreted by the brain. The electro- magnetic radiation can vary in intensity (per- ceived as a difference in brightness level) and wavelength (perceived as a difference in hue or “color”). The quantum theory of vision maintains that light energy travels to the eye in the form of discrete or discontinuous changes in energy where wavelength frequen- cies correspond to definite energies of the light quanta called photons. The Dutch physi- cist Christiaan Huygens (1629-1693) first proposed the undulatory theory, which forms a part of the wave theory of light that sup- planted the earlier corpuscular/particle the- ory. The wave theory offers a ready explana- tion of interference, diffraction, and polariza- tion of light but fails to explain the interaction of light with matter, the emission and absorp- tion of light, photoelectricity, and other phe- nomena. These can be explained only by a quasi-corpuscular theory involving packets of energy - light quanta or photons. The quantum theory was introduced by the German physi- cist Max Planck (1858-1947) in 1900. Ulti- mately, it appears that two models are re- quired to explain the phenomenon of light. According to the complementarity principle of the Danish physicist Niels Bohr (1885-1962), a system such as an electron can be described either in terms of particles or in terms of wave motion. Theories of vision are systematic at- tempts to account for the various phenomena of visual perception in relation to the known structure and functions of the visual organs. Included by extension is the study of photore- ceptors; the action of nerves and nerve end- ings [cf., Hering’s law of equal innervation - 619 named after the German physiologist Karl Ewald Hering (1834-1918), states that the muscles of each eye always operate in syn- chrony because they receive the same innerva- tion; the study of responses to light in lower organisms; the higher psychological implica- tions of light, color, form, and their temporal and spatial relations (cf., Harvey’s principle - when a grating is viewed, the number of verti- cal stripes per unit of total breath is overesti- mated and the number of horizontal stripes is underestimated; Leonardo’s paradox - named after the Italian artist/scientist Leonardo da Vinci (1452-1519), refers to da Vinci’s asser- tion that it is not possible to reproduce via a painting what a person sees binocularly, be- cause in binocular vision, each eye sees some- thing that the other eye does not see; Hering’s law of identical visual direction - in binocular vision, any pair of corresponding lines of di- rection in objective space are represented by a single line of direction in visual space; and the superposition hypothesis - the binocular vision of newborn infants blends together the mo- nocular visual responses of the two eyes, even when the visual stimulus evokes binocular rivalry in adults, and suggests that such blend- ing is replaced by binocular rivalry after the development/emergence of stereopsis at about age 8-12 weeks old (cf., Brown & Miracle, 2003). In his computational theory of vision, the English psychologist David C. Marr (1945-1980) makes a formal analysis of per- ception that is based on a theory of vision that attempts to explain how the pattern of light falling on the retinas of the eyes is trans- formed into an internal representation of the colors, shapes, and movements of what is observed; three stages are involved in the process: the “primal sketch,” the “two-and- one-half dimensional sketch,” and the “three- dimensional model” description. The ana- tomical and physiological basis for vision may be hypothesized much as is the case for the theories of color vision; for example, the three-component Young-Helmholtz theory; the antagonistic/opponent-process theory of Her- ing; the Ladd-Franklin genetic theory; and the von Kries duplicity theory. The cone cells (“daylight vision”) in the retina are responsi- ble for chromatic/color vision and visual acu- ity [cf., Charpentier’s law - named after the French physician Augustin Charpentier (1852- 1916), states that in the retinal fovea, the product of the area of a stimulus and its inten- sity is constant for stimuli at threshold intensi- ties; Charpentier bands - illusory black spokes that may be seen when a black disk with a white sector is rotated slowly; the blue-arc phenomenon - an effect produced by a stimu- lus at the center of the visual field against a dark background; it consists of a pair of blu- ish, luminous arcs seen as connecting the stimulus with the locus of the blind spot; the Troxler fading/effect - named after the Swiss- German physician/philosopher Ignaz P. V. Troxler (1780-1866), is the fading of visual objects in the periphery of the visual field when a point in its center is steadily fixated; this is due to the organization of the peripheral retina, which requires larger eye movements than are needed in the fovea, to break the ad- aptation brought about by steady fixation; the Ditchburn-Riggs effect - named after the Eng- lish physicist Robert William Ditchburn (1903-1987) and the American psychologist Lorin A. Riggs (1912- ), is the phenomenon of the rapid cessation of the vision of contours when the image of the contours undergoes prolonged stabilization with respect to the retina; and the Rayleigh equation - named after the English physicist Lord J. W. S. Rayleigh (1842-1919), is an index of one’s color vision given by the proportion of light from the red and green portions of the visible spectrum that need to be mixed to make a standard yellow]. The rod cells (“night-time vision”) are sensitive to minute amounts of light but are not sensitive to colors (cf., Ka- neko’s photochemical theory of vision). Be- cause of the anatomical features of the visual system, the left visual field is represented in the right occipital lobe of the brain, and the right visual field is represented in the left oc- cipital lobe. It is much easier to trace anatomi- cally the visual pathway from the retina to the occipital lobes than it is to explain and under- stand how the eyes and the brain interact to produce the perception of vision (cf., mind’s eye theory - proposes an as-yet-unidentified neurological structure located in the brain where visual information obtained from the two eyes or from long-term memory is stored temporarily while being processed as a visual 620 image, allowing one to reason from visual images; the Cheshire cat effect - relies on the phenomenon of binocular rivalry, where each eye has a different input from the same part of the visual field, and where motion in the field of one eye can cause either the entire image to disappear or parts of the image to be erased; the movement captures the brain’s attention momentarily; this effect is named after the Cheshire cat in Lewis Carroll’s “Alice’s Ad- ventures in Wonderland” where the cat van- ishes slowly, beginning with the end of its tail and ending with its grin that remained some time after the rest of the cat had disappeared). More is known about how photochemical processes and mechanisms operate in the rod cells than about the cone cells. In addition to responding directly to light, the receptor cells are affected, also, by the surrounding receptor cells. Studies have shown that there are both inhibitory and excitatory effects when neighboring receptor cells fire simultaneously. Other studies indicate that various cells in the visual cortex are maximally activated by ob- jects in the visual field with specific shapes, of particular orientations, and moving in particu- lar directions. For instance, D. Hubel and T. Wiesel hypothesize the existence of four gen- eral types of hierarchically organized cells (simple, complex, lower-order hypercomplex, and upper-order hypercomplex), and this no- tion has found anatomical support from other research, but the theory that those cells are arranged hierarchically is not yet supported. Over 100 years ago, the German physican and psychologist Hermann Aubert (1826-1892) provided a number of theoretical and lawful propositions concerning visual acuity and perception; cf., Listing’s law of visual ac- commodation - named after the German phy- sicist Johann Benedict Listing (1808-1882), refers to the case where, if the eye moves from a primary position to any other position, the torsional rotation of the eyeball in the new position is the same as it would be if the eye had turned about a fixed axis, and lies at right angles to the initial and final directions of the line of regard; and Alexander’s law - named after the Austrian otologist Gustav Alexander (1873-1932), refers to nystagmus, produced either by rotation or thermally, that can be accentuated voluntarily by moving the eyes in the direction of the jerky component of the nystagmus. Among Aubert’s eponymous ref- erents are the following: the Aubert-Fleischl paradox/phenomenon - named after Aubert and the Austrian physiologist Marxow Ernst Fleischl (1846-1891), is a perceptual effect whereby a moving stimulus seems to move more slowly when the observer fixates on the stimulus than when she or he fixates on the background; the Aubert-Forster phenomenon - named after Aubert and the Polish-born Ger- man ophthalmologist Carl F. R. Forster (1825- 1902), refers to the situation where two ob- jects of different physical sizes are placed at different distances from the observer such that both subtend the same number of degrees of visual arc, the physically closer one can be recognized over a greater area of the retina than the physically more distant one; the Au- bert phenomenon - refers to the case where a single vertical straight-line stimulus is pre- sented to an observer, and the line is displaced perceptually as the observer tilts his/her head (cf., the Muller effect - named after the Ger- man psychologist Georg Elias Muller (1850- 1934), refers to the case where an observer views a luminous vertical rod in the dark, and it appears to be tilted out of vertical in the same direction as the head; this effect occurs only with small tilts of the head); and the Au- bert-Forster law - a generalization regarding visual acuity based on the Aubert-Forster phenomenon that states that objectively small objects can be distinguished as two at greater distances from the fovea than objectively lar- ger objects subtending the same visual angle (cf., the Alice in Wonderland effect - is a vis- ual defect where one sees things as smaller than they are in actuality; in a clinical context, the Alice in Wonderland syndrome refers to depersonalization and “Lilliputian hallucina- tions,” that is, hallucinations involving objects that appear to be extremely small, derived from Jonathan Swift’s (1726) novel, Gulli- ver’s Travels in which the imaginary country of Lilliput has inhabitants who are only six inches tall; and associative/ geometric illusion - a visual misperception in which one part of an object or image is viewed erroneously due to the effect of another object/image; Appen- dix A provides a listing of various visual illu- sions/effects). See also ADAPTATION, [...]... VITAMIN MODEL OF EMPLOYEE SATISFACTION See WORK/CAREER/ OCCUPATION, THEORIES OF VIVIDNESS/CLEARNESS, LAW OF See ASSOCIATION, LAWS/PRINCIPLES OF VOLLEY/PERIODICITY THEORY AND VOLLEY PRINCIPLE See AUDITION/ HEARING, THEORIES OF von DOMARUS PRINCIPLE See SCHIZOPHRENIA, THEORIES OF von FREY’S FOUR-ELEMENT THEORY See SOMESTHESIS, THEORIES OF von KRIES’ COEFFICIENT LAW In the context of the phenomenon of chromatic... PROCESSING /THEORIES 632 WORK ADJUSTMENT, THEORY OF See WORK/CAREER/OCCUPATION, THEORIES OF WORK/CAREER/OCCUPATION, THEORIES OF The psychological study of work, career, and occupational factors ranges from theories of decision-making in career development to ergonomic/ergopsychometry/anthropometry, human engineering/human factors, work fatigue/efficiency, applications research, and work motivation theories Theories... PSYCHOPATHOLOGY, THEORIES OF REFERENCE Davis, E W (1985/1997) The serpent and the rainbow New York: Simon & Schuster ZONE/STAGE THEORIES OF COLOR VISION Zone- or stage -theories of color vision include several theories that give separate accounts of the processes at various stages or levels of the visual mechanism, such as receptor-, retina-, and optic nerve fiberlevels Examples of the zone/stage theories of color... LATERALITY THEORIES; PERCEPTION (II COMPARATIVE APPRAISAL), THEORIES OF; PERSONALITY, THEORIES OF; SELFCONCEPT THEORY REFERENCES Mach, E (1886/1959) The analysis of sensations and the relation of the physical to the psychical New York: Dover Mach, E (1902) The analysis of experience Jena, East Germany: Fisher Witkin, H A (1950) Individual differences in ease of perception of embedded figures Journal of Personality,... position on each of the three dimensions (cf., Wundt’s formulation of three principles of emotional expression as a reformulation of Darwin’s principles: the principles of innervation, association of analogous sensations, and relation of movements to images) Wundt’s theory of feeling stimulated a great deal of research in his own, and rival, laboratories but it has not withstood the test of time Wundt... a satisfied employee) The theories of motivation and adjustment have practical implications for workrelated activities in organizations and contribute to the maximization of job satisfaction and worker morale See also BALANCE, PRINCIPLES/THEORY OF; DECISION-MAKING THEORIES; DEVELOPMENTAL THEORY; LEADERSHIP, THEORIES OF; MASLOW’S THEORY OF PERSONALITY; MOTIVATION, THEORIES OF; ORGANIZATIONAL/INDUSTRIAL/SYSTEMS... language - holds that the structure of a language is a dependent function of the patterns of thought embedded in the particular culture) See also BEHAVIORIST THEORY; CHOMSKY’S PSYCHOLINGUISTIC THEORY; CONCEPT LEARNING/CONCEPT FORMATION, THEORIES OF; LANGUAGE ACQUISITION THEORY; LANGUAGE ORIGINS, THEORIES OF; PIAGET’S DEVELOPMENTAL STAGES THEORY; SPEECH THEORIES; THOUGHT, LAWS OF REFERENCES Watson, J B (1924)...621 PRINCIPLES/LAWS OF; ATTENTION, LAWS/PRINCIPLES/ THEORIES OF; COLOR VISION, THEORIES/ LAWS OF; DOPPLER EFFECT/PRIN-CIPLE/SHIFT; IMAGERY/MENTAL IMAGERY, THEORIES OF; NORMAL DISTRIBUTION THEORY; PERCEPTION (I GENERAL), THEORIES OF; PERSONAL EQUATION PHENOMENON; PURKINJE EFFECT/PHENOMENON/SHIFT REFERENCES Aubert, H (1865) Physiologie... WOLPE’S THEORY/TECHNIQUE OF RECIPROCAL INHIBITION WATERFALL ILLUSION/EFFECT See APPENDIX A WATSON’S THEORY See BEHAVIORIST THEORY WAVE THEORY OF LIGHT See VISION/ SIGHT, THEORIES OF WEAK LAW OF EFFECT See EFFECT, LAW OF WEAR-AND-TEAR THEORIES OF AGING See AGING, THEORIES OF WEBER-FECHNER FECHNER’S LAW LAW See WEBER’S LAW = relativity law = Weber’s fraction = Weber’s function = Weber’s ratio The German physiologist/psychophysicist... production of the “white sensation.” Hartridge describes an experiment that fails to corroborate certain assumptions of Willmer’s theory, namely, that strong stimulation of the rods and cones simultaneously would cause an appreciation of green, yellow, or orange, whereas weak stimulation of those receptors should result in the perception of violet, mauve, or crimson Holbourn offers a criticism of Willmer’s . THEORY. WAVE THEORY OF LIGHT. See VISION/ SIGHT, THEORIES OF. WEAK LAW OF EFFECT. See EFFECT, LAW OF. WEAR-AND-TEAR THEORIES OF AG- ING. See AGING, THEORIES OF. WEBER-FECHNER LAW GENERALIZA- TION, PRINCIPLES OF. UNIVERSALISM, DOCTRINE OF. See MIND/MENTAL STATES, THEORIES OF. UNIVERSALISTIC THEORIES. See WORK/CAREER/OCCUPATION, THEO- RIES OF. UNIVERSAL LAW OF GENERALIZA- TION one’s perceived duration and estimation of time. See also FRAISSE’S THEORY OF TIME; GUY- AU’S THEORY OF TIME; SOMESTHESIS, THEORIES OF; TIME, THEORIES OF. REFERENCES Vierordt, K. von (1868).