Efeitos dos sintomas de insônia no processamento visual em adultos

Abstract

Insomnia is a sleep disorder characterized by difficulty initiating and maintaining sleep, accompanied by a persistent sense of inadequate and non-restorative sleep, with negative impacts on daytime performance and quality of life. Additionally, clinical psychophysics suggests that insomnia states may influence aspects of visual information processing. In this context, two studies were conducted to investigate visual processing in adults with insomnia symptoms (Study Group – SG) and individuals without insomnia symptoms (Control Group – CG), aged between 18 and 45 years (SG: mean = 26.33 years, SD = 5.91; CG: mean = 25.75 years, SD = 5.29). The first study assessed achromatic contrast sensitivity using the Metropsis software, with spatial frequencies ranging from 0.2 to 14.5 cycles per degree (cpd). The sample consisted of 9 volunteers in the SG and 12 in the CG. Statistical analysis, performed using the Mann-Whitney test, revealed no significant differences between the groups at any of the analyzed spatial frequencies. The second study examined eye movement patterns during a visual search task, using two eye-tracking devices: the Tobii TX300 Eye Tracker in João Pessoa and the Tobii Pro Nano in Divinópolis. A total of 21 volunteers participated in the SG (mean = 27.90 years, SD = 7.589) and 18 in the CG (mean = 27.00 years, SD = 5.412). The results showed no statistically significant differences in eye-tracking metrics, such as first fixation duration, total fixation duration, and total number of fixations. However, the groups presented significant differences in the scores of the Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), certain factors of the Dysfunctional Beliefs and Attitudes about Sleep Scale (DBAS-16), and the Depression, Anxiety, and Stress Scale (DASS-21). Thus, the findings of this study do not indicate significant alterations in visual processing, either in contrast sensitivity or in fixation patterns, in individuals with insomnia symptoms. Given the absence of differences between groups in visual measures, future investigations exploring other visual and neurophysiological measures are essential to enhance the understanding of the effects of insomnia on perceptual processing. Furthermore, it is important to note that this study is not a clinical intervention investigation but rather focuses on understanding the visual mechanisms associated with insomnia.