Purpose: There is evidence that attention can modulate ocular dynamics, but its effects on accommodative dynamics have yet to be fully determined. We investigated the effects of manipulating the capacity to focus on task-relevant stimuli, using two levels of dual-tasking (arithmetic task) and auditory feedback, on the accommodative dynamics at three different target distances (500, 40 and 20 cm). Methods: The magnitude and variability of the accommodative response were objectively measured in 20 healthy young adults using the Grand Seiko WAM-5500 autorefractor. They fixated on a Maltese cross while performing an arithmetic task with two levels of complexity (low and high mental load), being provided with two levels of auditory feedback (low and high feedback), and without performing any mental task or receiving feedback (control). The accommodative and pupil dynamics were monitored during the 90 seconds period of the 15 trials (5 experimental conditions x 3 target distances). Results: The lag of accommodation was sensitive to the attentional state (P=0.001), observing a lower lag of accommodation for the high feedback in comparison to the control condition (corrected P-value=0.009). The imposition of mental load while fixating on a distant target led to a greater accommodative response (corrected P-value=0.010), but no effects were found for the near targets. There was a main effect of the experimental manipulation on the accommodative variability (P<0.001), with the use of auditory feedback improving the functioning of the accommodative system. Conclusions: Our data show that the accommodative dynamics is affected by varying the capacity to focus on task-relevant stimulus, supporting an association between attention and ocular dynamics.
Bibliographical noteThis is the peer reviewed version of the following article: Redondo, B, Vera, J, Molina, R, Davies, LN, & Jiménez, R. Accommodative dynamics and attention: the influence of manipulating attentional capacity on accommodative lag and variability. Ophthalmic Physiol Opt 2020, which has been published in final form at https://doi.org/10.1111/opo.12690. This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.
Redondo, B., Vera, J., Molina, R., Davies, L., & Jiménez, R. (2020). Accommodative dynamics and attention: the influence of manipulating attentional capacity on accommodative lag and variability. Ophthalmic and Physiological Optics. https://doi.org/10.1111/opo.12690