Multiple cues are typically available for perceiving the 3D slant of surfaces, and slant perception has been used as a test case for investigating cue integration. Previous evidence suggests that texture and stereo slant cues contribute in an optimal Bayesian manner. We tested whether a Bayesian model could also account for perceptual underestimation of slant from texture. One explanation proposed by Todd, Christensen, and Guckes (2010) is that slant from texture is based on an inaccurate optical variable. An alternative Bayesian explanation is that perceptual underestimation is due to the influence of frontal cues and/or a frontal prior, which is weighted according to the reliability of slant cues. We measured slant perception using a hand-alignment task for conditions that provided only texture, only stereo, or combined texture and stereo cues. Slant estimates from monocular texture showed large biases toward frontal, with proportionally more underestimation at low slants than high slants. Slant estimates from stereo alone were more accurate, and adding texture information did not reduce accuracy. These results are consistent with a frontal influence that is decreasingly weighted as slant information becomes more reliable. We also included conditions with small cue conflicts to measure the relative weighting of texture and stereo cues. Consistent with previous studies, texture had a significant effect on slant estimates in binocular conditions, and the relative weighting of texture increased with slant. In some cases, perceived slant from combined stereo and texture cues was higher than from either cue in isolation. Both the perceptual biases and the cue weights were generally consistent with a Bayesian model that optimally integrates texture and stereo slant cues with frontal cues and/or a frontal prior.

No abstract

Aim To describe the optical coherence topographic (OCT) characteristics and outcome of vitrectomy with triamcinolone acetonide (TA)-assisted epiretinal tissue removal and gas tamponade in eyes with myopic foveoschisis (MF). Methods We examined 101 myopic eyes, and the OCT characteristics of 18 eyes (18%) with an MF were studied. Six eyes underwent vitrectomy with TA-assisted epiretinal tissue removal and gas tamponade. The postoperative outcome measures were bestcorrected visual acuity (BCVA), resolution of the MF as determined by OCT, and complications. Results OCT scans showed an isolated MF in three (17%) eyes, and the MF were associated with two or more macular anomalies in 15 (83%) eyes. A foveal detachment was found in 13 (72%), lamellar macular hole in 4 (22%), and a tractional epimacular membrane in 11 (61%) of the 18 eyes. Six eyes underwent surgery, in which the epiretinal tissue was made visible by intravitreal TA and completely removed. The median BCVA significantly improved from 20/400 preoperatively (range, 20/1000-20/160) to 20/160 postoperatively (range, 20/200-20/40; P ¼ 0.03, Wilcoxon signed-rank test). The mean VA improved by 5.6 lines. OCT showed a complete reattachment of the fovea in four (67%) eyes and a small subfoveal or parafoveal detachment in two (33%) eyes. Conclusions MF is commonly observed in highly myopic eyes and most are associated with one or more macular anomalies. Vitrectomy with TA-assisted complete removal of all tractional premacular structures followed by gas tamponade resulted in good visual and anatomical outcomes for treating MF.

No abstract

In this paper, we summarize the Holocene environmental history of the lower Yangtze region, east China, based on the sedimentary records and microfossil diatom, pollen, fungal and charcoal data that were published in the past two decades. We then examine the linkage between changes in the coastal environment and the development of rice agriculture in the region, with reference to the available archaeological evidence and historical archives. Based on the sedimentary and archaeological evidence, we conclude that during the early Holocene sea-level movements and sedimentary processes significantly changed the region’s landscape from an open, brackish water environment to a largely enclosed, wetland system. This newly established freshwater marsh environment provided a habitat favourable to rice agriculture. The early Neolithic farmers took the opportunity presented to them and started rice cultivation in locations where freshwater wetland systems were established. During the middle Holocene, environmental conditions were largely stable, and the coastal wetlands evolved slowly. Environmental change was only a supportive player in the Neolithic cultural processes, because the Neolithic people were able to adapt to these changes and took advantages of the newly emerging marsh land for food collection and production. Around 4200 years ago, the prosperous Liangzhu society fell, but there is no evidence to suggest the fall was related to a significant environmental change. The coastal environment continued to evolve slowly during the late Holocene. But this period saw rapid technological development in irrigation and flood protection, and the environmental factor was reduced to background noise. Throughout the Holocene, the main strategy taken by the Neolithic people to cope with environmental change was migration to find better food sources. Along with this strategy was the development of technology in landscape management to ensure a more reliable food production in addition to food collection through hunting, gathering and fishing.