Selective visual attention: A mechanism for optimal adjustment of sensory processing to task requirements - from method development to human psychophysics and monkey single cell recordings

This cumulative dissertation consists of three studies. In the first study we showed that feature-based attention actively suppresses non-relevant features and therefore it can be seen as a selection process different from object-based attention. In the second study we investigated the influence of the neuronal response in visual area MT on the behavioral response of the animals. We observed an increase in the transient neuronal response to the behaviorally relevant speed-change and a reduction of the latency of this response in trials with fast reaction times. This modulation in the neuronal response corresponds to an improvement of the neuronal representation of the speed-change. Furthermore, a similar modulation of the neuronal representation of the speed-change was found for attended trials. In the third study we developed a new chronical recording device. It consists of an exchangeable multielectrode array that is reversibly fixed to a new type of recording chamber. This array allows for bidirectional movement of six electrodes.