Abstract
Visual discomfort is the adverse effects reported by some on viewing certain stimuli, such as stripes and certain filtered noise patterns. Stimuli that deviate from natural image statistics might be encoded inefficiently, which could cause discomfort (Juricevic, Land, Wilkins and Webster, 2010, Perception, 39(7), 884–899), possibly through excessive cortical responses (Wilkins, 1995, Visual Stress, Oxford, Oxford University Press). A less efficient visual system might exacerbate the effects of difficult stimuli. Extreme examples are seen in epilepsy and migraines (Wilkins, Bonnanni, Prociatti, Guerrini, 2004, Epilepsia, 45, 1–7; Aurora and Wilkinson, 2007, Cephalalgia, 27(12), 1422–1435). However, similar stimuli are also seen as uncomfortable by non-clinical populations, eg, striped patterns (Wilkins et al, 1984, Brain, 107(4)). We propose that oversensitivity of clinical populations may represent extreme examples of visual discomfort in the general population. To study the prevalence and impact of visual discomfort in a wider context than typically studied, an Internet-based survey was conducted, including standardised questionnaires measuring visual discomfort susceptibility (Conlon, Lovegrove, Chekaluk and Pattison, 1999, Visual Cognition, 6(6), 637–663; Evans and Stevenson, 2008, Ophthal Physiol Opt 28(4) 295–309) and judgments of visual stimuli, such as striped patterns (Wilkins et al, 1984) and filtered noise patterns (Fernandez and Wilkins, 2008, Perception, 37(7) 1098–1013). Results show few individuals reporting high visual discomfort, contrary to other researchers (eg, Conlon et al, 1999).