A neural correlate of visual discomfort from flicker

Abstract

The theory of "visual stress" holds that visual discomfort results from overactivation of the visual cortex. Despite general acceptance, there is a paucity of empirical data that confirm this relationship, particularly for discomfort from visual flicker. We examined the association between neural response and visual discomfort using flickering light of different temporal frequencies that separately targeted the LMS, L-M, and S postreceptoral channels. Given prior work that has shown larger cortical responses to flickering light in people with migraine, we examined 10 headache-free people and 10 migraineurs with visual aura. The stimulus was a uniform field, 50 degrees in diameter, that modulated with high-contrast flicker between 1.625 and 30 Hz. We asked subjects to rate their visual discomfort while we recorded steady-state visually evoked potentials (ssVEPs) from early visual cortex. The peak temporal sensitivity ssVEP amplitude varied by postreceptoral channel and was consistent with the known properties of these visual channels. There was a direct, linear relationship between the amplitude of neural response to a stimulus and the degree of visual discomfort it evoked. No substantive differences between the migraine and control groups were found. These data link increased visual cortical activation with the experience of visual discomfort.

Cortical Mechanisms of Visual Hypersensitivity in Women at Risk for Chronic Pelvic Pain

“…Increased unpleasantness was also associated with increased visual stimulation brightness intensity, albeit seen across fewer electrode locations. These findings replicate previous investigations that demonstrated associations between unpleasantness and increased cortical activity in response to aversive visual stimulation ( Adjamian et al, 2004 ; Haigh et al, 2013 ; Huang et al, 2011 ; Patterson Gentile & Aguirre, 2020 ). Our visual task showed that SSVEPs, a measure of cortical excitation, were effectively modulated and related to self-reported measures of unpleasantness, thus promoting the use of SSVEPs conducive to the study of MSH.…”

“…Given previous literature linking visual discomfort and cortical measures across various visual stimulus parameters (Haigh et al, 2013;O'Hare, 2016;Patterson Gentile & Aguirre, 2020), we hypothesized that brightness intensity would modulate SSVEP amplitudes, . CC-BY 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.…”

“…Given previous literature linking visual discomfort and cortical measures across various visual stimulus parameters ( Haigh et al, 2013 ; O’Hare, 2016 ; Patterson Gentile & Aguirre, 2020 ), we hypothesized that brightness intensity would modulate SSVEP amplitudes, particularly in V1 (electrode Oz). Given the comorbidity of MSH in chronic visceral pain, we hypothesized that the relationship between visual unpleasantness and cortical excitation would be similarly affected by bladder pain.…”

Improving user experience of SSVEP BCI through low amplitude depth and high frequency stimuli design

“…contrast) 4 , increasing stimuli luminance 5 or reducing user’s distance from SSVEP stimulator 6 have proven to be successful approaches to maximise SNR. These methods are however detrimental to the user experience as they make the RVS more visually intrusive 7 . Over prolonged exposition, RVS may cause eye strain leading to visual fatigue but also reduction in task performance and headaches 3 .…”

Cortical mechanisms of visual hypersensitivity in women at risk for chronic pelvic pain

“…These findings replicate previous investigations that demonstrated associations between unpleasantness and increased cortical activity in response to aversive visual stimulation. 2,34,42,76 Our visual task showed that SSVEPs, a measure of stimulus-driven oscillatory activity in the cortex, were effectively modulated and related to self-reported measures of unpleasantness, thus promoting the use of SSVEPs to the study of visual sensitivity. Our study supports evidence that increased unpleasantness to a stimulus is associated with increased sensory pathway activity, 15 even in a nonsomatic pathway such as vision.…”