The challenges of developing a contrast-based video game for treatment of amblyopia

Abstract

Perceptual learning of visual tasks is emerging as a promising treatment for amblyopia, a developmental disorder of vision characterized by poor monocular visual acuity. The tasks tested thus far span the gamut from basic psychophysical discriminations to visually complex video games. One end of the spectrum offers precise control over stimulus parameters, whilst the other delivers the benefits of motivation and reward that sustain practice over long periods. Here, we combined the advantages of both approaches by developing a video game that trains contrast sensitivity, which in psychophysical experiments, is associated with significant improvements in visual acuity in amblyopia. Target contrast was varied adaptively in the game to derive a contrast threshold for each session. We tested the game on 20 amblyopic subjects (10 children and 10 adults), who played at home using their amblyopic eye for an average of 37 sessions (approximately 11 h). Contrast thresholds from the game improved reliably for adults but not for children. However, logMAR acuity improved for both groups (mean = 1.3 lines; range = 0–3.6 lines). We present the rationale leading to the development of the game and describe the challenges of incorporating psychophysical methods into game-like settings.

A dichoptic custom-made action video game as a treatment for adult amblyopia

“…A similar conclusion was reached by Hussain et al (2014) in a study that tested the benefits of a monocular videogame with a PL task. The dichoptic game we tested here, resulted in a similar level of improvement in VA (Fig.…”

“…This is the case for multihour monocular PL training applied to the amblyopic eye (Astle, Webb, & McGraw, 2010, 2011; Chung, Li, & Levi, 2008, 2012; Hussain et al, 2012; Levi, 2012; see recent reviews in Levi & Li, 2009; Levi & Polat, 1996; Levi, Polat, & Hu, 1997; Zhang et al, 2014), and for video game training, either off-the shelf action games (Jeon, Maurer, & Lewis, 2012; e.g. Li et al, 2011) or customized games (Hussain et al, 2014). …”

“…For example, playing an off-the-shelf action video game (Medal of Honor) monocularly for 40 h results in improvements in visual acuity and other visual functions (Li et al, 2011) and reduces the “attentional blink” (Li, Ngo, & Levi, 2015). Recently, Hussain et al (2014) have developed a contrast-based videogame for treating both adults and children with amblyopia.…”

“…Interestingly, despite the very different methodologies employed (PL or videogame play; monocular or dichoptic presentation, a few hours of training to several months), most studies report, on average, improvement in visual acuity of between 1 and 2 lines on a LogMAR chart (for recent reviews see Hussain et al, 2014; Levi, 2012; Levi & Li, 2009), and variable improvement in stereopsis (Levi, Knill, & Bavelier, 2015 – this issue).…”

Virtual Interactive Environment for Low-Cost Treatment of Mechanical Strabismus and Amblyopia

“…Later Li, Ngo, and Levi [25] observed that after 40 s of video game play, there was a reduction in the blinking action of the eye. Hussain et al [26] developed a video game with adaptive contrast for the treatment of 20 people with amblyopia and obtained excellent results.…”