Über Wahrnehmungsverhalten beim 8- bis 10wöchigen Säugling

Zusammenfassung Im Rahmen einer Systemtheorie des Verhaltens und der Persönlichkeit und auf dem Hintergrund der Ergebnisse der Berner Längsschnittuntersuchungen wird eine Hypothese über die Genese der Wahrnehmung entwickelt, wonach die frühesten Wahrnehmungen im wesentlichen Verarbeitungen der Reizwirkungen in einer von zwei Klassen von Verhaltenssystemen sind, nämlich der Abwendung und Selbstsicherung (A-Systeme) bzw. der Zuwendung zur Außenwelt (Z-Systeme).In einem Experiment mit 8-, 9- und l0wöchigen Säuglingen wurde das Wahrnehmungsverhalten in Abhängigkeit von verschiedenen Reizfiguren, von der individuellen Eigenart und vom Aktivationsniveau des Kindes mit Hilfe eines Zeitstichprobenverfahrens beobachtet. Der auf die Differenzierung zwischen den verschiedenen Reizfiguren entfallende Varianzanteil steigt mit zunehmendem Alter an, während die Wirkung der autonomen Aktivationsprozesse allmählich zurücktritt. Mit 10 Wochen kann eine geordnete Form oder gute Gestalt leichter verarbeitet werden als eine mehr zufällige Form.Einige Probleme im Zusammenhang mit Annahmen, Methoden und Ergebnissen des Experiments werden diskutiert, darunter die Theorie der Formwahrnehmung, die Genese von Subjekt- und Objektsystem und die beschränkte Bedeutung der Methode der bevorzugten Fixierung in der Erforschung der Säuglingswahrnehmung.

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Summary Within the framework of a System Theory of behavior and personality and against the background of the results of the Bernese Longitudinal Studies, a hypothesis of the genesis of perception is developed. It states that the earliest perceptions are essentially integrations of the effects of stimuli into one of two classes of behavioral systems, viz. withdrawal and self-preservation (A-systems) or, respectively, approach to the outer world (Z-systems).The perceptual behavior of 8-, 9-, and 10-week-old infants as a function of different stimulus forms, individuality, and activation level was observed by means of a time-sampling rating method. The proportion of variance accounted for by the differences between stimuli was found to increase with age; at the same time the effect of autonomic activation processes was decreasing. At the age of 10 weeks the infant can work up an orderly form or good Gestalt more readily than a more irregularly-shaped form.Some problems in connection with the assumptions, methods, and results of the study are then discussed, including form perception theory, the genesis of subject- and object-system, and some restriction of the method of preferred fixation in the study of infant perception.

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Gegenwärtig als Canada Council Postdoctoral Fellow an der York University in Toronto, Ont., Canada. Der Verfasser möchte seinem verehrten Lehrer Richard Meili seinen herzlichen Dank für die Anregung dieser Arbeit ausdrücken.     

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