Role of ocular aberrations in photopic spatial summation in the fovea.

An adaptive optics vision simulator was used to measure the role of ocular aberrations in the photopic foveal spatial summation curve for three young subjects. After the correction of the ocular aberrations over a 6 mm pupil, the increment luminance threshold was lowered for small stimuli and the estimated area of complete summation (Ricco's area) was reduced by a factor of 2.6 on average. These results show that the image spread due to natural ocular aberrations partly accounts for the spatial summation observed in the fovea in the photopic light regime.

[1]  D R Williams,et al.  Supernormal vision and high-resolution retinal imaging through adaptive optics. , 1997, Journal of the Optical Society of America. A, Optics, image science, and vision.

[2]  A. Bradley,et al.  Statistical variation of aberration structure and image quality in a normal population of healthy eyes. , 2002, Journal of the Optical Society of America. A, Optics, image science, and vision.

[3]  J. Werner,et al.  The area of complete scotopic spatial summation enlarges with age. , 1998, Journal of the Optical Society of America. A, Optics, image science, and vision.

[4]  M E Wilson,et al.  Invariant features of spatial summation with changing locus in the visual field , 1970, The Journal of physiology.

[5]  V. Glezer.  The receptive fields of the retina. , 1965, Vision research.

[6]  Karen M. Hampson,et al.  Adaptive optics and vision , 2008 .

[7]  Wilson S. Geisler,et al.  The relative contributions of pre-neural and neural factors to areal summation in the fovea , 1991, Vision Research.

[8]  John S. Werner,et al.  Spatial summation in human cone mechanisms from 0° to 20° in the superior retina , 2000 .

[9]  John L. Barbur,et al.  Effects of higher-order aberrations on contrast acuity as a function of light level , 2008 .

[10]  P Artal,et al.  Calculations of two-dimensional foveal retinal images in real eyes. , 1990, Journal of the Optical Society of America. A, Optics and image science.

[11]  H. Barlow.  Temporal and spatial summation in human vision at different background intensities , 1958, The Journal of physiology.