Hysteresis in accommodation.
Under certain conditions the accommodative response is not a simple function of accommodative stimulus, but depends as well upon the history of the stimulus. Experimental evidence points to multiple mode control of accommodation as being responsive: a high-gain feedback control mode responds to blur; a second mode causes a drift to bias set level when visual stimuli are removed. We extend a model consistent with these results and use it to predict the results of a new experimental paradigm, 'pushdown' accommodation. Finally, we extend the model to a third mode of behaviour, schematic accommodation, which encompasses instrument myopia, proximal accommodation and voluntary accommodation.
Neveu
C
C
Program in Vision Science, School of Optometry, University of California, Berkeley 94720, USA.
Stark
L
L
D000065:Accommodation, Ocular / Q000502:physiology*; D000328:Adult; D005246:Feedback; D006801:Humans; D008297:Male; D008433:Mathematics; D008954:Models, Biological; D012684:Sensory Thresholds / Q000502:physiology