Perceptual holistic color combination analysis of Papilionidae butterflies as aesthetic objects.

In this study, we clarified the holistic color combination rules of human-preferred Papilionidae butterflies by examining the hue, lightness, and chroma. A set of 118 Papilionidae butterfly images used in our previous study was analyzed. These images were classified via hierarchical density-based spatial clustering based on perceptual similarities of colors that were obtained from a subjective image classification experiment. The color combinations of the clustered images were determined based on representative colors that were analyzed by a Gaussian mixture model with minimum message length and the color combination types defined in our previous study. Consequently, we obtained the following holistic color combination rules for Papilionidae: 1) contrasting lightness, similar chroma, and similar hue, 2) contrasting lightness, contrasting chroma, and similar hue, 3) similar lightness, similar chroma, and complementary hue, and 4) similar lightness, similar chroma, and similar hue. These rules suggest that minority color harmony theories are valid under particular conditions.

Trypophobia is predicted by disgust sensitivity, empathic traits, and visual discomfort.

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., visual discomfort). We examined whether trypophobia is associated with disgust sensitivity, empathic traits, and visual discomfort. Japanese adults (n = 126) completed four scales: the Trypophobia Questionnaire, which measures trypophobia proneness; the Disgust Scale-Revised, which measures disgust sensitivity; the Interpersonal Reactivity Index, which measures empathic traits; and the Visual Discomfort Scale, which measures proneness to visual discomfort. Trypophobia proneness was found to be predicted by Core disgust sensitivity (i.e., threat of disease), Personal Distress (i.e., the empathic trait of self-oriented emotional distress), and proneness to visual discomfort. We suggest a number of potential factors relating to individual differences in trypophobia and the possible cognitive and perceptual mechanisms underlying trypophobia.

Illusory visual motion stimulus elicits postural sway in migraine patients.

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. The participants' postural sway was measured when they closed their eyes either immediately after (Experiment 1), or 30 s after (Experiment 2), viewing the stimuli. The patients swayed more than the controls when they closed their eyes immediately after viewing the illusory motion (Experiment 1), and they swayed less than the controls when they closed their eyes 30 s after viewing it (Experiment 2). These results suggest that static visual stimuli with illusory motion can induce postural sway that may last for at least 30 s in patients with migraine.

Memory color effect induced by familiarity of brand logos.

BACKGROUND: When people are asked to adjust the color of familiar objects such as fruits until they appear achromatic, the subjective gray points of the objects are shifted away from the physical gray points in a direction opposite to the memory color (memory color effect). It is still unclear whether the discrepancy between memorized and actual colors of objects is dependent on the familiarity of the objects. Here, we conducted two experiments in order to examine the relationship between the degree of a subject's familiarity with objects and the degree of the memory color effect by using logographs of food and beverage companies. METHODS AND FINDINGS: In Experiment 1, we measured the memory color effects of logos which varied in terms of their familiarity (high, middle, or low). Results demonstrate that the memory color effect occurs only in the high-familiarity condition, but not in the middle- and low-familiarity conditions. Furthermore, there is a positive correlation between the memory color effect and the actual number of domestic stores of the brand. In Experiment 2, we assessed the semantic association between logos and food/beverage names by using a semantic priming task to elucidate whether the memory color effect of logos relates to consumer brand cognition, and found that the semantic associations between logos and food/beverage names in the high-familiarity brands were stronger than those in the low-familiarity brands only when the logos were colored correctly, but not when they were appropriately or inappropriately colored, or achromatic. CONCLUSION: The current results provide behavioral evidence of the relationship between the familiarity of objects and the memory color effect and suggest that the memory color effect increases with the familiarity of objects, albeit not constantly.

Self-medication behaviors among Japanese consumers: sex, age, and SES differences and caregivers' attitudes toward their children's health management.

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. This study examined Japanese consumers' self-medication practices and attitudes toward over-the-counter (OTC) medicines based on their sex, age, and socioeconomic status (SES). METHODS: The participants were 403 adults (Mage = 41.1 years, SD = 16.22). A quota sampling method was employed based on age group, and participants completed an online questionnaire. RESULTS: Participants in the 20-29 age group reported medical costs as an obstacle in seeing a doctor; in contrast, transportation was a mitigating factor for elderly people. Regarding SES, people at lower SES levels chose to rest instead of seeing a doctor or purchasing over-the-counter (OTC) medicines when sick. They also placed more value on national brand OTC medicines than private brands (likely due to advertisements). This finding suggests individuals with a low SES do not select OTC medicines based on their effects or ingredients. Regarding attitudes toward OTC medicines, Japanese participants seemed to be unaware of the potential for abuse and side effects associated with OTC medicines. Finally, in relation to caregivers' self-medication practices for their children, the majority of participants reported taking their children to the hospital since children tend to receive free medical care. Furthermore, caregivers with a high educational background are more confident in being able to help manage their children's health. CONCLUSIONS: Our results suggest that health and medical discrepancies among Japanese consumers pose new social problems. In Japan, universal health care is available, but the cost of receiving medical care is not completely free of charge. Thus, we hope that the government will attempt to meet the various needs of patients and support their well-being. Consumers also have to be more independent and aware of their health management, as self-medication practices will continue to play a more significant role in healthcare. More research is needed to find ways to teach Japanese consumers/patients of both the benefits and risks of over-the-counter (OTC) medicines.

Evaluation of cerebral dyschromatopsia using color afterimage.

Cerebral dyschromatopsia is traditionally evaluated by color discrimination tests such as the Farnsworth-Maunsell 100 Hue Test. These tests are also used to evaluate color-perception deficits caused by eye disease, and they do not tell us whether color perception is impaired in the eye or in the brain. Here, we used color afterimage to isolate color-perception deficits in the brain from those in the eyes, in a patient with cerebral dyschromatopsia. The results showed that the patient perceived color afterimage of yellow and blue with abnormal duration and chromaticity. On the other hand, the patient performed normally on the Farnsworth-Maunsell 100 Hue Test. We conclude that the color afterimage test would be useful to evaluate color perception in the brain.