Altered Eye-Movement Patterns During Text Reading in Obsessive-Compulsive Disorder and Internet Gaming Disorder

Abstract

Obsessive-compulsive disorder (OCD) and internet gaming disorder (IGD), which are similar in that both involve repetitive behaviors and related with cognitive dysfunctions, frequently begin in early adolescence, which is a critical period for learning. Although the deterioration in cognitive functioning caused by these conditions may have adverse effects on information processing, such as text reading, there has been no comprehensive research on the objective indicators of altered reading patterns in these patients. Therefore, we evaluated eye-movement patterns during text reading in patients with OCD or IGD. In total, 20 patients with OCD, 28 patients with IGD and 24 healthy controls (HCs) participated in the reading task using an eye tracker. We compared the fixation durations (FDs), saccade amplitudes and eye-movement regressions of the three groups during reading. We explored relationships between the parameters reflecting altered reading patterns and those reflecting the severity of clinical symptoms. The average FDs and forward saccade amplitudes did not differ significantly among the groups. There were more eye-movement regressions in patients with OCD than in patients with IGD and HCs. No correlation was found between altered eye-movement patterns during reading and the severity of clinical symptoms in any of the patient groups. The significantly increased number of regressions (NRs) in the OCD group during reading may reflect these patients' difficulties with inferential information processing, whereas the reading pattern in the IGD group is relatively intact. These findings suggest that patients with OCD and patients with IGD have different eye-movement patterns during reading reflecting distinct cognitive impairments in the two patient groups.

Keywords: eye-movement; information processing; internet gaming disorder; obsessive-compulsive disorder; reading.

Figure 1

Image of the sample scene of the reading task with the eye-movement variables superimposed. The text, written in Korean in the box in bold, was presented in the task. Gray circles mean that the fixation and size of the circle varied according to the duration of each fixation. Arrows with dotted lines indicate forward saccades. Arrows with bold lines indicate regressions.

Figure 2

The distribution of data by group for total duration (A), number of regression (NR) (B), fixation duration (FD) (C) and saccade amplitude (D). In each plot, solid line indicates the OCD group and dotted line indicates the IGD group and the dashed line indicates the HC group. The vertical line indicates the mean value of the group in (A) and (B). In (C) and (D), the vertical line indicates the median value of each groups Abbreviations: OCD, Obsessive-compulsive disorder; IGD, internet gaming disorder; HC, healthy control.

Figure 3

NRs in the three groups according to post hoc analyses using the Bonferroni method. The error bar indicates the standard error. *P < 0.05. Abbreviations: OCD, obsessive-compulsive disorder; IGD, internet gaming disorder; HC, healthy control.