Learn More
The eye's longitudinal chromatic aberration (LCA) is known to drive 'reflex' accommodation to moving objects, but the evidence is not as clear for stationary objects. The present study examined whether accommodation can be driven by static simulations of the effects of defocus and LCA. Accommodation was recorded continuously while each of 12 subjects viewed(More)
We wished to determine how pupil size and mean accommodation response level interact to influence the fluctuations of accommodation. A dynamic infra-red optometer was used to record accommodation responses while subjects viewed a steady target at two stimulus levels (1.5 and 3 D) through four pupils (1, 2, 4 and 6 mm). It was found for most subjects that(More)
Human saccadic eye movements have three types of overshoot: dynamic overshoot, lasting 10-30 ms; glissadic overshoot, lasting 30-500 ms; and static overshoot, which is amended-after a delay of about 200 ms-by a subsequent corrective saccade. Glissades are the slow drifting eye movements occasionally seen at the end of saccadic eye movements. Glissades are(More)
A study was conducted with the purpose of examining the possible effects of vertical and horizontal eye movements upon accommodation. A special Badal stimulator was made which was vertically rotatable around the center of an eye. The stimulator was attached to the Three-Dimensional Optometer III (TDOIII), which could measure accommodation, eye movement, and(More)
The horizontal and vertical components of oblique saccadic eye movements are not always tightly crosslinked; often they are completely independent. Most of the time the two components do not start and end simultaneously. The neurological bursting and pausing of the extraocular motoneurons that underlie the generation of these oblique movements will,(More)
Two field studies were conducted at a research station in Tampa, Florida to assess the removal of bacteriophage PRD1 from wastewater in septic tank drainfields. Infiltration cells were seeded with PRD1 and bromide and the effects of effluent hydraulic loading rate and rainfall on virus removal were monitored. Septic tank effluent samples were collected(More)
PURPOSE The authors investigated the potential of subject instructions to alter the static accommodative stimulus-response function. They also investigated whether the reduced cue environment of the Badal optical system leads to accommodative responses different from those that occur for targets presented in real space. METHODS Static accommodative(More)
The properties of small monochromatic targets as accommodative stimuli are not well understood. We used a dynamic optometer to record accommodation responses to monochromatic disc targets (1.0-27.3 min arc) and to a Maltese cross. Accommodation responded adequately to points as small as 13.6 min arc. The response to these small targets is relevant to the(More)
Previous studies have demonstrated that accommodation will respond to sine gratings in which the relative modulations of red, green and blue image components have been altered to simulate the effects of defocus and longitudinal chromatic aberration. The present study aimed to determine the tolerance of the accommodative system to relative phase shifts in(More)
It has been suggested that in the presence of astigmatism some individuals make cyclic changes in focus over the astigmatic interval to obtain better visual performance. The aim in the present study was to identify such cyclic accommodative behavior and to characterize the variability of the response in the presence of astigmatism. The dynamic accommodation(More)