Mechanisms of Target Selection and Feature Binding in Visual Object Recognition: Evidence from the Asynchronous Presentation of Target Features

by Bernd Sch�nw�lder

It has become common knowledge that if there is a unifying principle that enables the human brain to realize its tremendous capabilities, then it is its highly parallel organisation of underlying processes. However, the mystery of integrati on of all these distributed processes into the single, coherent consciousness that we experience, also referred to as the "binding problem", is still one of the most controversial research topics in modern cognitive neuroscience. This thesis aims to contribute methodological as well empirical advances to the understanding of general, formalised properties of different types of integration mechanisms for visual featural information, which are supposed to be involved in early as well as in late processing stages of the visual system. It focuses on developing mathematical methods that employ behavioural reaction time data to differentiate between different implementation variants of integrational mechanisms. These methods are developed with respect to their application in the visual search paradigm.A modified version of the visual search paradigm, which involves feature change asynchronies to temporally separate featural manipulations in the presentation of stimuli, is applied to investigate into current research topics of pre-attentive feature integration. In a series of experiments recent findings about the temporal organization of feature integration and binding processes are addressed. In the focus of this experimental investigation is the question in how far differences in processing delays between dimension-specific featural information, like color, motion or orientation information, can account for temporal misbindings as has been recently reported in the literature.