Review article
How depression changes the way of looking – a review of research on changes in eye tracker indicators in patients suffering from depression

Changes in cognitive functioning are now widely recognized as a very important aspect of depression and depressed mood states. In addition to traditional, behavioral indicators of cognitive process quality, psychophysiological methods, including eye movement analysis, are increasingly used. Eye movement analysis is potentially a valuable tool in exploration of cognitive changes in depressed mood states as the neural circuits involved in eye movement control – especially the fronto-parietal network – are also altered in depression. The following article is a review of studies that recorded eye movements associated with cognitive tasks performance in groups of people suffering from mood disorders. Three groups of cognitive functions are discussed that were significantly altered in people with mood disorders: attention, memory, and the ability to integrate information (analysis and reasoning). Measurement of eye movements were mainly used to study the presence and characteristics of cognitive bias, and, to a less extent, to assess the influence of differences in the recorded eye movements on cognitive functioning per se. This research shows that people with mood disorders are characterized by, among other things, extended attention and often direct the gaze on images or words with negative emotional content. As a result, eye tracking indicators show a significantly greater number of fixations or return visits to negative stimuli compared to the control group.