Perception of Coherent Motion in Infantile Nystagmus Syndrome

Abstract

Purpose Research on infantile nystagmus syndrome (INS) and motion perception is limited. We investigated how individuals with INS perform coherent motion tasks. Particularly, we assessed how the null position affects their performance. Methods Subjects with INS and controls identified the direction of coherent motion stimuli (22 subjects with INS and 13 controls) in a two-alternative forced-choice design. For subjects with INS, testing was done at the null position and 15 degrees away from it. If there was no null, testing was done at primary gaze position and 15 degrees away from primary. For controls, testing was done at primary gaze position and 20 degrees away from primary. Horizontal and vertical motion coherence thresholds were determined. Results Subjects with INS showed significantly higher horizontal and vertical motion coherence thresholds compared with controls at both gaze positions ( P < 0.001). Within the INS group, for 12 subjects with INS who had an identified null position, no differences in coherence thresholds were found between their null and 15 degrees away from it ( P > 0.05). Conclusions Coherent motion perception was impaired in subjects with INS. The null position did not significantly influence motion coherence thresholds for either horizontal or vertical motion.

Measurement of visual function in infantile nystagmus: a systematic review

“…Jones et al [22] and Fadardi et al [23] assessed the impact of stress and mental load on VA, respectively. Costa et al [24], Dunn et al [25] and Roberts et al [26] assessed the impact of gaze angle on VA, while two studies by Dai et al [27][28] assessed its impact on motion perception. Pascal and Abadi [29] and Tailor et al [30] each assessed the impact of visual crowding in IN.…”

“…The coherent motion study used 100 limited-lifetime dots travelling at 10°/s, shown for 650 ms within a 10° aperture. [28] Participants with IN performed worse than controls in both tasks. In addition, nystagmats with an identified null zone had lower thresholds for horizontal motion; this difference was significant for velocity discrimination but not for coherent motion.…”

“…In two studies by Dai et al [27][28], the impact of gaze angle on velocity discrimination and coherent motion perception was assessed for horizontal and vertical motion at two gaze angles; at the null zone and 15° away from it (for nystagmats), or at primary gaze and 20° away in the case of control participants.…”

Comparison of stereopsis thresholds measured with conventional methods and a new eye tracking method

“…In diagnostics, eye trackers have emerged as helpful instruments in ophthalmology, serving various applications [21]. They can assess ocular motility and detect disorders such as strabismus and nystagmus [22][23][24][25], evaluate binocular vision by examining eye coordination [26], and assist in visual field testing to monitor glaucoma progression and other visual impairments [27,28]. Furthermore, eye trackers can analyze reading difficulties or dyslexia by observing eye movements, fixations, and saccades during reading tasks [29,30].…”

Visual Function and Neuropsychological Profiling of Idiopathic Infantile Nystagmus

“…It is already known how IIN affects predominantly ocular motor abilities [ 19 , 20 , 21 ], while the literature has scarcely focused on the involvement of other visual functions, apart from some reports concerning, in particular, velocity discrimination [ 22 ], spatial bisection acuity [ 23 ], motion perception [ 24 ], and visual crowding [ 25 , 26 ]. Such dysfunctions may come along with a disruption in the development of cognitive competencies and a negative repercussion on functional vision (i.e., how the child functions in everyday life vision-related tasks, including academic abilities).…”