The electrophysiology of IOR in overt visual search

If we focus our attention on a specific object in the environment, this helps us to perceive this object better. However, if we return our attention to it after a short break, we find it more difficult to regain focus. This phenomenon is known as "Inhibition of Return" (IOR). The IOR mechanism is particularly helpful when we are searching for something: It prevents us from repeatedly looking at the same places or objects where we have already searched unsuccessfully. Instead, it directs our attention to new areas in the environment where the probability of finding what we are looking for is higher.

IOR is a well-researched phenomenon that has been described in detail by recording eye movements. Electroencephalography (EEG) has also been used to better understand the role of brain activity in IOR. However, these two methods have so far mostly been used separately, so that no uniform picture of IOR has yet emerged. The aim of this research project is therefore to utilise both methods together in order to gain a more comprehensive understanding of IOR.

The simultaneous use of eye movement measurement and EEG is a relatively new method which, although challenging, has the potential to provide important new insights. For example, it is possible to investigate what exactly happens in the brain while we scan our environment with our eyes. In particular, the EEG makes it possible to record the processes in the brain that take place at the moment when we look at an object for the first time or when we look at it again after a short pause - in other words, precisely when IOR occurs.

As part of this FWF project, we are carrying out a series of investigations to answer the following questions, among others: Under what conditions does IOR occur? Does it only occur when we are actively looking for something, or also in general when we look at our environment? How flexible is IOR? Can it be switched on and off within a short time if the task requires it? How does IOR progress over time? How long does it last, for example? How is IOR reflected in brain activity?

This project is dedicated to basic research. It addresses the fundamental question of how human attention works and which processes in the brain play a role in this. Attention is the basis of almost all higher cognitive functions. It is essential for forming memories and helps us to focus on certain things and avoid distractions. Ultimately, in this project we are investigating how people successfully interact with their environment.