Hiroyuki Nishimoto

The images that our eyes perceive are slightly different from the objects. Images in visual space are illusions. However, they are indeed based on optics. In physical space, parallel lines never intersect. In visual space, however, parallel lines intersect at the vanishing point. This is not limited to the human eye; camera lenses produce images similarly. If visual space is spherical, the phenomenon of intersecting parallel lines is no mystery. This paper provides a new geometric model considering the intersection of parallel lines at vanishing points.

Background: Time disorientation is one of the main symptoms observed in patients with dementia; however, their clock-reading ability has not been fully reported. Objective: This study aimed to investigate the clock-reading ability of both digital and analog clocks in patients with dementia. We newly devised the clock-reading test (CRT) and the number-reading test (NRT) to assess cognitive factors that may affect clock-reading ability. Furthermore, the discriminating power of the CRT was calculated. Methods: 104 participants were categorized based on their Mini-Mental State Examination (MMSE) scores as follows: subjective cognitive decline ∼ mild cognitive impairment (SCD∼MCI, N = 43), early Alzheimer’s disease (AD) (N = 26), and middle-to-late AD (N = 35). Their cognitive abilities were evaluated using the clock-drawing test (CDT), CRT, and NRT. Results: Cognitive decline leads to impairment of clock-reading ability which is more pronounced in the analog clocks than digital ones. This deficit in clock-reading is attributed to a loss of semantic memory regarding clocks at all stages. Additionally, visuospatial dysfunction and reduced ability of number recognition may lead to deficit in clock-reading in the advanced stage of AD. The discriminating power of the CRT (analog) (AUC = 0.853) was high enough to detect cognitive decline. Conclusion: Digital clocks are more readable by patients with dementia. Since reading clocks is closely associated with daily life, the CRT has proved to be a useful tool. A decline of analog clock-reading may be an early detector for the onset of dementia in elderly patients.

Background: With the rapid aging of the population, the issue of driving by dementia patients has been causing increasing concern worldwide. Objective: To investigate the driving difficulties faced by senior drivers with cognitive impairment and identify the specific neuropsychological tests that can reflect specific domains of driving maneuvers. Methods: Senior drivers with cognitive impairment were investigated. Neuropsychological tests and a questionnaire on demographic and driving characteristics were administered. Driving simulator tests were used to quantify participants’ driving errors in various domains of driving. Results: Of the 47 participants, 23 current drivers, though they had better cognitive functions than 24 retired drivers, were found to have impaired driving performance in the domains of Reaction, Starting and stopping, Signaling, and Overall (wayfinding and accidents). The parameters of Reaction were significantly related to the diagnosis, and the scores of MMSE, TMT-A, and TMT-B. As regards details of the driving errors, “Sudden braking” was associated with the scores of MMSE (ρ= –0.707, p < 0.01), BDT (ρ= –0.560, p < 0.05), and ADAS (ρ= 0.758, p < 0.01), “Forgetting to use turn signals” with the TMT-B score (ρ= 0.608, p < 0.05), “Centerline crossings” with the scores of MMSE (ρ= –0.582, p < 0.05) and ADAS (ρ= 0.538, p < 0.05), and “Going the wrong way” was correlated with the score of CDT (ρ= –0.624, p < 0.01). Conclusion: Different neuropsychological factors serve as predictors of different specific driving maneuvers segmented from driving performance.

錯視の原理として諸説論じられているが，遠近法が幾何学的錯視の基本原理であるとすると，多くの錯視が比較的シンプルに説明できる．錯視がこのように遠近感覚に基づく副産物であるとすると，錯視は心が作り出す単なる幻想ではなく，必要に迫られて身につけた脳力の一つである．従ってこのように経験や学習により習得した能力であるならば，いずれAIも学習により全ての錯視を経験するとした観察研究の論文．

In the early Meiji period, Japanese government promoted to introduce Western drawing. In increasing demand for the domestic production of the drawing materials, in compliance with a painter Chiyoji Yazaki,, a factory of Kyoto started to produce soft pastels for the first time in Japan in 1919.In this study, we investigated what kind of colors the then Japanese artists desired, by examining the colors of the soft pastels at the time of the factory's founding. One of the characteristics of soft pastel is the prearranged wide variety of colors. Moreover, there are so-called distinctive traditional colors according to the regions and countries. Our hypothesis is that Japanese traditional colors were included in the original soft pastels.With the Munsell color system, we examined three Japanese-made soft pastel sets and one French-made set.We compared the relations between the pastel colors and those respective traditional colors. In parallel, we conducted interview survey with the manufacturer, the current president, about the startup history.The result indicates that the Japan's first soft pastels were provided in response to the senses of color that Japanese traditionally have. Furthermore, to create the delicate color tones, the founder employed a unique material compounding methods. The fact that the founder was a Sunday painter and had sympathy for the artists must have contributed to come to produce Japanese soft pastels.