Publications by authors named "Shinichi Koyama"

Dots on natural backgrounds can elicit significant pupillary constrictions within the entire image phase associated with parasympathetic activation, suggesting disgust rather than fear. Although studies have reported that dots on faces elicit stronger disgust than dots on non-face backgrounds, it remains unclear whether dots on a face elicit stronger pupil constrictions than non-face backgrounds. Pupillometry was used while viewing dots on faces and compared with luminance- and spatial frequency-controlled images (dots on phase-scrambled faces) and luminance-controlled images (face only, phase-scrambled faces).

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The Uncanny Valley hypothesis implies that people perceive a subjective border between human and robot faces. The robot-human border refers to the level of human-like features that distinguishes humans from robots. However, whether people's perceived anthropomorphism and robot-human borders are consistent across different robot occupations remains to be explored.

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Introduction: Since the enactment of the revised Pharmaceutical Affairs Act in Japan in 2009, self-medication practices have increased in the country. However, studies report that consumers pay little attention to the medication facts and risks indicated on the packages of over-the-counter (OTC) medicines, which could be a potential risk. Since the COVID-19 pandemic, the digital transformation of purchasing OTC medicines has progressed.

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Designing an over-the-counter medication electronic health record (OTC-EHR) may help improve OTC usage. An online survey for the conceptual OTC-EHR design examined participant characteristics, attitudes towards obtaining user-shared OTC medication information, health-related application usage, and the inclination to share anonymized health information. Descriptive statistics, tests to assess statistical significance, and text mining were used to analyze the results.

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Trypophobia has attracted scientific attention in recent years. Few related studies have recruited participants using online methods, and even less is known about health communication in an environment where trypophobia was first widely discussed (i.e.

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Background: Studies have shown that viewing a cluster of dots evokes feelings of discomfort in viewers and that the discomfort becomes especially strong when the dots are placed on background images of human skin. This phenomenon has been explained by the physical properties and spatial and semantic relationships between the dots and the background. However, it was not known whether the perceived, as well as the physical, spatial relationships contributes to the generation of discomfort.

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Eye movements as the indicators of human information processing have been studied in many domains. However, it is not clear how users' eye movements differ among specific product attribute, while visual impression of a product plays a crucial part in distinguishing product designs. Therefore, this paper attempts to establish guidance for exploring eye tracking applications in design concept validations through two case studies.

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To study the size-resolved characteristics of airborne bacterial community composition, diversity, and abundance, outdoor aerosol samples were analysed by 16S rRNA gene-targeted quantitative PCR and amplicon sequencing with Illumina MiSeq. The samples were collected using size-resolved samplers between August and October 2016, at a suburban site in Toyama City and an urban site in Yokohama City, Japan. The bacterial communities were found to be dominated by Actinobacteria, Firmicutes, and Proteobacteria.

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Parkinson's disease (PD) is associated with various cognitive impairments. However, the nature of cognitive modification in patients with PD remains to be elucidated. In the present study, we examined whether patients with PD could correct and maintain subjective time duration and line length estimation.

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A cluster of dots such as lotus seed pods evokes extremely strong disgust when it is placed on human and animal skins. However, few empirical studies have examined the role of the background image, such as skin, in the generation of disgust. In this study, we investigated whether the orientation of background faces influences the disgust evoked by the dot pattern.

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Background: Visual stimuli, such as stripes and texts, can induce "visual discomfort" including perceptual and somatic symptoms. Individuals reporting high levels of visual discomfort might experience migraine headache and may have reduced reading efficiency due to visual perceptual difficulties. This study aimed to develop and validate the Japanese version of the Visual Discomfort Scale, which measures proneness to visual discomfort.

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Most amputees experience phantom limb, whereby they feel that the amputated limb is still present. In some cases, these experiences include pain that can be alleviated by "mirror therapy." Mirror therapy consists of superimposing a mirrored image of the moving intact limb onto the phantom limb.

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Trypophobia refers to disgust for a cluster of objects, and is considered an extension of disgust for dangerous objects. Furthermore, trypophobic images possess certain spatial properties that can induce perceptually unpleasant states (i.e.

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Article Synopsis
  • The study explores how the brain perceives ownership and control over limbs through the sensorimotor system, particularly focusing on prosthetic arms.
  • Nine unilateral upper-limb amputees participated, divided into frequent users of their prosthetic arm and those who rarely used it.
  • Results showed that frequent users felt more stable with their prosthesis and had a stronger sense of agency, while rare users experienced instability when using it, suggesting that body awareness influences postural control in amputees.
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The scientific exploration of the self has progressed, with much attention focused on the Embodied Sense of Self (ESS). Empirical studies have suggested the mechanisms for self-representation. On the other hand, less attention has been paid to the subjectivity itself of the self.

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Altering physical actions when responding to changing environmental demands is important but not always effectively performed. This ineffectiveness, which is an error of social behavior generated by mutual interactions, is not well understood. This study investigated mechanisms of a hesitant behavior that occurs in people walking toward each other, causing people to move in the same direction when attempting to avoid a collision.

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Although the perception of visual motion modulates postural control, it is unknown whether illusory visual motion elicits postural sway. The present study examined the effect of illusory motion on postural sway in patients with migraine, who tend to be sensitive to it. We measured postural sway for both migraine patients and controls while they viewed static visual stimuli with and without illusory motion.

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Most patients, post-amputation, report the experience of a phantom limb. Some even sense voluntary movements when viewing a mirror image of the intact limb superimposed onto the phantom limb. While delayed visual feedback of an action is known to reduce a sense of agency, the effect of delayed visual feedback on phantom motor sensation (i.

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This paper reviews clinical neuropsychological studies that have indicated that the recognition of a person's identity and the recognition of facial expressions are processed by different cortical and subcortical areas of the brain. The fusiform gyrus, especially the right fusiform gyrus, plays an important role in the recognition of identity. The superior temporal sulcus, amygdala, and medial frontal cortex play important roles in facial-expression recognition.

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Acquired higher brain dysfunction is for the most part due to cerebral vascular disease, but epilepsy may also be a cause. In this study with five patients, we discuss the advantages of anti-epileptic drugs (AEDs) for persistent higher brain dysfunction. The patients showed chronic amnesia or acute aphasia, with associated symptoms like personality change.

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Background: Since 2009, when the revised Pharmaceutical Affairs Act was enacted in Japan, self-medication practices have increased. Because the concept of self-medication was recently introduced in Japan, few studies exist on this topic. Therefore, it is necessary to explore how self-medication is practiced.

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Background: Posterior cortical atrophy (PCA) is a degenerative disease characterized by progressive visual agnosia with posterior cerebral atrophy. We examine the role of the picture naming test and make a number of suggestions with regard to diagnosing PCA as atypical dementia.

Methods: We investigated 3 cases of early-stage PCA with 7 control cases of Alzheimer disease (AD).

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Prosopagnosia, the inability to recognize faces, has a history going back to Charcot and Hughlings-Jackson, but was first named by Bodamer in 1947. Its anatomical loci are still unclear. However, progressive prosopagnosia is normally linked to right dominant temporal lobe atrophy, and diagnosed as part of frontotemporal lobar degeneration.

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Background: To investigate whether Japanese multiple sclerosis (MS) patients with minor brain lesion loads have attention deficits and brain atrophy, and to correlate their circumstance.

Method: Twenty-one Japanese patients with relapsing-remitting MS were included in this study. Attention deficits were evaluated using Clinical Assessment for Attention (CAT) standardized according to age groups.

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We examined two male patients (64 and 70 years old) with rapid eye movement sleep behaviour disorder (RBD) using cognitive tests, myocardial (123)I-metaiodobenzylguanidine (MIBG) scintigraphy, and dopamine positron emission tomography (PET) imaging. One patient had impaired social cognition and decision-making skills and reduced MIBG reuptake, and dopamine PET imaging indicated striatal terminal loss. The other patient had normal social cognition and reduced MIBG reuptake, but no abnormalities were detected by dopamine PET imaging.

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