{"references": ["Vitu, F. (2005). Visual extraction processes and regressive saccades in reading. In G. Underwood (Ed.), Cognitive processes in eye guidance. Oxford, NY: Oxford University Press. pp. 1-32.", "Dimigen, O., Hohlfeld, A., Sommer, W.; Jacobs, A., Engbert, R. & Kliegl, W. (2005). Measuring ERPs during left-to-right reading, Poster presented at the IX International Conference on Cognitive Neuroscience, Havana, Cuba", "Dimigen, O., Sommer, W., Hohlfeld, A., Jacobs, Engbert, R., Kliegl, R. (2006). Concurrent recording of EEG and gaze position: Measuring effects of word predictability during left-to-right reading of normal sentences. Journal of Cognitive Neuroscience, Supplement 224", "Frazier & Rayner (1982). Making and correcting errors during sentence comprehension: Eye movements in the analysis of structurally ambiguous sentences. Cognitive Psychology, 14, pp. 178-210", "Engbert & Kliegl (2003). Microsaccades uncover the orientation of visual attention. Vision Research, 43, pp. 1035-1045"]}

About 15% of reading saccades move the eyes backwards in the text. To study the neurophysiological correlates of such regressions, we co-registered gaze position and ERPs of 54 subjects during natural, left-to-right reading. Sentences were grammatically diverse but contained no syntactic violations or local ambiguities. Accompanying the onset of long-range regressions, we observed a late centroparietal positivity, closely resembling the P600 component commonly observed for syntactic violations and garden-path sentences in traditional ERP experiments. This suggests that the P600 indexes individual comprehension difficulty or parsing problems even in the absence of syntactic ambiguity. Co-registration of eye movements and ERPs may help to differentiate between regressions caused by oculomotor overshoot, word identification failures, and syntactic parsing problems.

The abstract of this poster was published in the Journal of Eye Movement Research, Vol. 1, Number 5, p. 129.