Preventing Substance Abuse Among American-Indian Adolescents: A Bicultural Competence Skills Approach

Tobacco, alcohol, and drug use are problems for American-Indian people. We reviewed these problems and the explanations for them and described a bicultural competence skills approach for preventing substance abuse with American-Indian adolescents. Data from a study of that approach suggest its efficacy with American-Indian youth. At posttest and a 6-month follow-up, American-Indian subjects who received preventive intervention based on bicultural competence skills concepts improved more than did American-Indian subjects in a no-intervention control condition on measures of substance-use knowledge, attitudes, and interactive skills, and on self-reported rates of tobacco, alcohol, and drug use. Our findings have implications for future substance-abuse prevention research with American-Indian people.     

The height of a stereokinetic cone: A quantitative determination of a 3-D effect from 2-D moving patterns without a “rigidity assumption”

Summary When a circular disc with an eccentric dot painted on it is set in slow circular motion, a three-dimensional solid object appears to the observer: the stereokinetic cone. The cone shows a well-defined height and tilt. All current theories of how the visual system can extract 3-D percepts from 2-D moving patterns, are based on a rigidity assumption hypothesis. But this assumption cannot explain why the stereokinetic cone appears to have a well-defined height. An alternative hypothesis is proposed here, which avoids the rigidity assumption and is based on a minimization process of the relative velocity differences between all the points of the rotating pattern. The hypothesis allows a quantitative prediction of the stereokinetic cone height both when the rotating disc is circular and when it is elliptical. The predictions are in good agreement with previously reported experimental results and with our own observations.     

Conceptualizations of valence and instrumentality: A fourfold model

Within the framework of valence-instrumentality (VI) theory, a fourfold model is developed to predict the contribution which is made by one outcome of an alternative to the valence of that alternative. The proposed model uses four subjective conditional probabilities which are based on the presence and absence of an alternative, and on the occurrence and nonoccurrence of an outcome. Valence is defined as the difference between the attractiveness values of the occurrence of an alternative (or an outcome) and the nonoccurrence of an alternative (or an outcome). Also, differences between subjective probabilities replace instrumentalities. Alternative valence-instrumentality formulations are analyzed in relation to the proposed fourfold model. The proposed model can be understood as a consistent application of Vroom's model (1964, Work and motivation, New York: Wiley), while other models are judged to be relatively deficient. The fourfold model, in combination with a matrix formulation of expectancy concepts, addresses a number of criticisms of VI theory and makes possible a test of the theory within the limits of its own assumptions.     

Meinungsänderung durch eigenes Handeln Die Rückwirkung einstellungskonträrer Agitation

Zusammenfassung Zur Klärung der Frage, ob und unter welchen Umständen einstellungskonträre Agitation auf den Agitator zurückwirkt, wurden Gruppen- und Einzelversuche durchgeführt. Als Versuchspersonen dienten insgesamt 409 männliche und weibliche Oberschüler und Studenten. In allen Versuchen mußten die Versuchspersonen Reden erfinden und halten. Die Messung der Meinungsänderung und einiger hypothetischer Variablen wurde mit Fragebogen vorgenommen, zum Teil wurden nach den Versuchen Interviews durchgeführt.Wir erhielten folgende Hauptergebnisse: Erfinden und Vortragen von Argumenten für einen zudiktierten Standpunkt führen, unabhängig voneinander und von der im Vortrag enthaltenen Argumentation, zu einer Meinungsänderung. Ihre Richtung und ihr Ausmaß sind außerdem abhängig vom Verhältnis der zudiktierten Stellungnahme zu anderen, bereits vorhandenen psychischen Inhalten — starke Verankerung der ursprünglichen Meinung führt zur Meinungsänderung im Gegensinne der Agitation (Bumerang-Effekt) — sowie vom Grad der Willentlichkeit der Handlung: bereits die Entscheidung, einen einstellungskonträren Standpunkt nach außen zu vertreten, kann zu einer Meinungsänderung führen. Das Lernen der Argumente, die Bewertung der eigenen Leistung, des Versuchs und Versuchsleiters sowie Eigenschaften eines Themas für sich erweisen sich nicht als alleinige Bedingungen der Meinungsänderung.Diese und andere, weniger wichtige Ergebnisse werden diskutiert. Die Theorie der kognitiven Dissonanz wird als beste einheitliche Erklärungsgrundlage der empirischen Befunde angesehen.

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Summary Experiments with groups and single persons were conducted to test the effect of persuasive behaviour on the communicator. 409 male and female high-school and university students served as subjects. In all experiments the subjects had to invent and verbalize speeches contradicting their own opinion. Opinion change and some hypothetical variables were measured by questionnaires, the sessions were partially followed by interviews.Main results: Inventing or speaking of arguments in favour of an appointed opinion lead, independently of each other and of the informational content of the arguments, to opinion change the direction and magnitude of which are, in addition, dependent on the relation of the argument to previously existent mental contents (if the original opinion is strongly anchored, the persuasive behaviour results in a boomerang effect), as well as the degree of volition of the subject's persuasive behaviour. (Already the decision to defend a point of view contrary to one's own may lead to opinion change). Learning of arguments and evaluation of own achievement, of the experiment and the experimenter as well as the qualities of a topic in itself cannot be shown to be the only conditions of opinion change.These and other, less important results are discussed; the theory of cognitive dissonance is considered the best uniform explanation of these empirical results.

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Diese Arbeit wurde von der philosophischen Fakultät der Ludwig Maximilians-Universität in München als Dissertation angenommen.Die referierten Versuche wurden durch das Yale Communication and Attitude Change Programme und die Gesellschaftder Freunde der Wirtschaftshochschule Mannheim e.V. finanziell gefördert. Der Verfasser dankt den genannten Institutionen für ihre Unterstützung.     

A new approach to the generation of visual stimuli for eye-movement research

An interactive, computer-controlled, visual stimulus generator is described, suitable for both psychophysical and neurophysiological experimentation on human subjects. The system core is a wide-screen electrostatic cathode-ray tube, which can be used both as a television monitor, to display standard video pictures, and as anx-y oscilloscope, so that a bright dot can be moved around the display by electrical signals. In addition, a third working mode is provided, according to which a time-compressed video picture of limited size (fast picture) plays the role that is typical of the spot in a standard oscilloscope. Through computer-assisted time compression, the frame period of the video signal is reduced to about one tenth of its standard value. The fast picture can accordingly be driven by even the fastest eye movements, and it can be displayed as a stabilized image, or, more generally, in the altered retinal feedback condition. Moreover, as compared with a standard video picture, the fast image can be “flashed” over much shorter time periods. Since a standard input video signal is used for both standard and fast video pictures, all the image processing facilities of commercial videographic systems can be fully exploited by the proposed device.