Shape Perception Is Altered by Normal Aging

Abstract

Shape perception is not robust to the effects of aging. Greater deficits were manifest for the discrimination of shape from texture than for the discrimination of closed contours.

The accuracy of home monitoring to detect disease activity during maintenance therapy for neovascular ARMD

“…The reasons for this are unclear but there may have been differences in the patient population, length of treatment or the training provided. Prior studies have identified that shape discrimination ability decreases with worse visual acuity, increasing age and more advanced ARMD [13,14]. However, an exploratory analysis of the agreement between subgroups in this study failed to find a trend to suggest better agreement according to participant age, baseline near acuity letter score or a "dry" macula on OCT imaging at the prior examination.…”

Visual Form Perception from Age 20 through 80 Years

“…Table 1 shows a summary of these previous results, and the estimated sample sizes for a power of 0.80 and an alpha of P < 0.05. 16,18,24,27 With the exception of collinear facilitation, the required sample size was less than 20 people in each group (aged 20-40 years and age 60-80 years). We decided to use a sample of approximately 10 per decade for all tasks (resulting in 20 people in the younger and older age groups), given the a priori expectation of some relationship in performance across tasks when tested in the same individuals.…”

“…18,19 The ability to detect and discriminate contours comprised of local elements declines 20 and is more susceptible to the effects of surrounding clutter. [21][22][23] Age-related differences exist in the perception of shapes defined by texture, 24 and for higher levels of form processing, such as facial matching when faces are displayed from different viewpoints. 25 Previous studies that have documented age-related changes to form perception generally have included two age groups: younger adults (usually below ages 35 to 40 years) and older adults (typically over the age of 60 years), and have conducted detailed experiments on a specific aspect of form perception (e.g., orientation discrimination, 12 center-surround suppression of perceived contrast, 18,19 contour integration, 22 shape discrimination 26 ).…”

Investigation of the segregated visual system

“…They often demonstrate impairments in visual motion sensitivity, including the perception of apparent motion, and have poorer orientation-judging capabilities Betts et al, 2007;Roudaia et al, 2010)(for a review, see (Andersen, 2012). It has been reported that aging also has an impact on form perception and shape discrimination (Habak et al, 2009;McKendrick et al, 2010;Weymouth and McKendrick, 2012) and figure-background separation (Chee et al, 2006), but it is not clear what changes accompany these impairments.…”

“…Although, some age-related gap exists between the simple and complex cells in V1 as regarding age-related deteriorations (Liang et al, 2012). Human investigations showed evidence in changes in shape perception (McKendrick et al, 2010;Weymouth and McKendrick, 2012) and also in visuo-spatial memory (Carp et al, 2010).…”