PURPOSE Some debate surrounds the accommodative mechanism in primates, particularly whether the lens equatorial diameter increases or decreases during accommodation. This study has been undertaken to measure the relationship between changes in lens diameter and refraction during accommodation in rhesus monkeys. METHODS Photorefraction was used to measure accommodation, and goniovideography wa...

PURPOSE To determine the distribution of negative relative accommodation (NRA) and positive relative accommodation (PRA) and its relationship with binocular vision indices in a young population. METHODS In this cross-sectional study conducted in a student population, samples were selected through multistage cluster sampling. All the samples underwent the measurement of uncorrected and correct...

Certain visual stimuli, such as striped patterns and filtered noise, have been reported to be uncomfortable. Some filtered noise patterns judged as uncomfortable are those with a relative decrease in contrast amplitude at high spatial frequencies, compared with the statistics typical of natural images. Decreased amplitude at high spatial frequencies is a characteristic often associated with per...

PURPOSE The purpose of this study was to compare the mean findings and the repeatability of the minus lens (ML) amplitude of accommodation (AA) at 33 cm and 40 cm. MATERIALS AND METHODS AA was measured from the dominant eye of 120 fully corrected subjects using the ML procedure when viewing the target at both 33 and 40 cm. Each measurement was repeated between 24 and 48 hours after the first ...

Pyramidal neurons in the rat hippocampus contain mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs) to which the adrenal steroid corticosterone binds with differential affinity. We have used intracellular recording techniques to examine MR-mediated effects on membrane properties of CA1 pyramidal neurons in hippocampal slices from adrenalectomized rats. Low doses of corticoster...

Background: The purpose of this research was to investigate the diurnal effect Ramadan fasting on amplitude accommodation and anterior segment parameters in visually healthy participants.Materials Methods: study included 68 individuals, aged 26–42 years. subjective measured using "minus lens" technique. Corneal refraction (K1, K2, Kmax), central corneal thickness, volume, chamber depth were eva...

Purpose: To assess the accommodation response after short reading periods using a tablet and a smartphone as well as determine potential differences in the accommodation response at various stimulus vergences using a Hartmann- Shack aberrometer. Methods: Eighteen healthy subjects with astigmatism of less than 1 D, corrected visual acuity of 20/20 or better, and normal findings in an ophthalmi...