Face inversion effect on perceived cuteness of infant faces.

Research has demonstrated that attractiveness evaluations of adult faces were less accurate when faces were inverted than upright. It remains unknown, however, whether a similar effect applies to perceived cuteness of infants, which is assumed to be based on elemental facial features called the "baby schema." In this research, we studied the face inversion effect on perceived cuteness of infant faces in a rating task and a two-alternative forced-choice (2AFC) task. We also examined beauty as a control dimension. Although the rating task revealed no inversion effect, the 2AFC task showed poorer discrimination performance with inverted faces than with upright faces in both evaluations. These results indicate that infant cuteness and beauty dimensions are correlated well with each other, and their perception not only relies on elemental features that are not strongly affected by inversion but is also affected by holistic facial configurations when a detailed comparison is required.

Task Difficulty Makes 'No' Response Different From 'Yes' Response in Detection of Fragmented Object Contours.

Two-alternative forced choice tasks are often used in object detection, which regards detecting an object as a 'yes' response and detecting no object as a 'no' response. Previous studies have suggested that the processing of yes/no responses arises from identical or similar processing. In this study, we investigated the difference of processing between detecting an object ('yes' response) and not detecting any object ('no' response) by controlling the task difficulty in terms of fragment length and stimulus duration. The results indicated that a 'yes' response depends on accurate and stable decisions through grouping processing, and a 'no' response might involve two distinct processing, including accurate decisions and intuitive decisions. Accurate decisions of 'no' may arise after the rejection of a 'yes' response with grouping processing, which is an accurate but slow response in an easy task. Intuitive decisions of 'no' arise as the result of breaking down the decision process when the received information was insufficient for grouping processing in a difficult task. Therefore, intuitive decisions of 'no' arise quickly but are inaccurate. The different processes associated with yes/no responses were discussed in terms of the hierarchal structure of object recognition, especially with respect to receiving information and grouping.

Large irides enhance the facial attractiveness of Japanese and Chinese women.

Since large eyes are often perceived to enhance facial attractiveness, many individuals are motivated to change their eyes' appearance. Colored contact lenses are often used by young women to darken the limbal rings of their irides, to increase their facial attractiveness. Among Westerners, wearing contact lenses with limbal rings enhances facial attractiveness; a similar effect might exist for East Asians whose irides are darker; although, the mechanism underlying these preferences in Westerners and East Asians might differ. In this study, we investigated whether larger irides increased the attractiveness of Japanese and Chinese women, and whether this effect was accompanied by changes in perceived friendliness or youthfulness. We manipulated eye size by enlarging only the iris or the whole eye, and asked participants to rate face stimuli in terms of facial attractiveness, friendliness, and youthfulness. We found that larger irides enhanced not only attractiveness but also perceived youthfulness and friendliness, and that there was a significant correlation between attractiveness and friendliness. Further, iris-enlarged faces were perceived as more attractive even when the iris was originally dark, as enlarged dark irides were confused with dilated pupils, which are often perceived as a sign of attraction.

Enlargement of female pupils when perceiving something cute.

It is reported that women's pupils dilate when they see a baby; it is unclear if this pupillary response is caused by the perception of cuteness itself. Since many objects besides babies can be perceived as cute, we investigated whether the perception of cuteness, or the type of object observed, is related to pupil dilation. In the first experiment, female participants were requested to rate the subjective cuteness of greyscale pictures of objects such as animals and foods; their pupil sizes were measured. The results showed a significant positive correlation between perceived cuteness and participants' pupil dilation. In the second experiment, participants rated the cuteness of images of female faces. Results revealed a significant negative correlation between perceived cuteness and pupil dilation. In our study, perceiving cuteness enlarged female observers' pupils except when observing female faces. Positive reactions associated with cuteness may be premised on the existence of unconscious perceptual alterations and physical responses.

Face Inversion Effect on Perceived Cuteness and Pupillary Response.

The face inversion effect reflects the special nature of facial processing and appears not only in recognizing facial identity or expression but also in subjective evaluation, such as facial attractiveness. Previous studies have revealed that the way in which we perceive attractiveness (beauty versus cuteness) differs our perceptual behavior. Therefore, the face inversion effect on attractiveness might differ based on the viewpoint of attractiveness. In this study, we measured pupillary response when judging the cuteness of facial stimuli and focused on the mechanism of perceiving attractiveness in terms of the effect of involuntary physical reaction. We investigated whether perceived cuteness - a kind of attractiveness - was affected by face inversion and whether the face inversion effect appeared in pupillary responses. We then conducted experiments in which participants observed inverted faces and rated the subjective cuteness of the faces, and we measured the participants' pupil size while they observed the facial stimuli. The results revealed a negative correlation between pupil changes and the perceived cuteness of inverted faces, which is consistent with the previous result of upright faces. Thus, we found that the perception of facial cuteness is little affected by face inversion, suggesting that the judgment of cuteness is processed differently from other types of attractiveness such as beauty. We also found that pupillary response is related to perceiving cuteness, which could lead to consistency in the perception of cuteness.

Object Categorization Processing Differs According to Category Level: Comparing Visual Information Between the Basic and Superordinate Levels.

Object category levels comprise a crucial concept in the field of object recognition. Specifically, categorization performance differs according to the category level of the target object. This study involved experiments with two types of stimulus sequences (i.e., forward condition: presenting the target name before the line-drawing stimulus; and reverse condition: presenting the target name after the line-drawing stimulus) for both basic- and superordinate-level categorizations. Adult participants were assigned to each level and asked to judge whether briefly presented stimuli included the same object and target name. Here, we investigated how the category level altered the categorization process. We conducted path analyses using a multivariate multiple regression model, and set our variables to investigate whether the predictors affected the categorization process between two types of stimulus sequence. Dependent variables included the measures of performance (i.e., reaction time, accuracy) for each categorization task. The predictors included dimensions and shapes of the line-drawings, such as primary and local shape information, shape complexity, subject estimation, and other shape variables related to object recognition. Results showed that the categorization process differed according to shape properties between conditions only for basic-level categorizations. For the forward condition, the bottom-up processing of primary visual information depended on matches with stored representations for the basic-level category. For the reverse condition at the basic-level category, decisions depended on subjective ratings in terms of object-representation accessibility. Finally, superordinate-level decisions depended on higher levels of visual information in terms of complexity, regardless of the condition. Thus, the given category level altered the processing of visual information for object recognition in relation to shape properties. This indicates that decision processing for object recognition is flexible depending on the criteria of the processed objects (e.g., category levels).

Beauty and cuteness in peripheral vision.

Guo et al. (2011) showed that attractiveness was detectable in peripheral vision. Since there are different types of attractiveness (Rhodes, 2006), we investigated how beauty and cuteness are detected in peripheral vision with a brief presentation. Participants (n = 45) observed two Japanese female faces for 100 ms, then were asked to respond which face was more beautiful (or cuter). The results indicated that both beauty and cuteness were detectable in peripheral vision, but not in the same manner. Discrimination rates for judging beauty were invariant in peripheral and central vision, while discrimination rates for judging cuteness declined in peripheral vision as compared with central vision. This was not explained by lower resolution in peripheral vision. In addition, for male participants, it was more difficult to judge cuteness than beauty in peripheral vision, thus suggesting that gender differences can have a certain effect when judging cuteness. Therefore, central vision might be suitable for judging cuteness while judging beauty might not be affected by either central or peripheral vision. This might be related with the functional difference between beauty and cuteness.

The impact of baby schema on perceived attractiveness, beauty, and cuteness in female adults.

Beauty and cuteness are considered to represent different aspects of attractiveness and to be distinguishable from each other by their respective reliance on neonate and sexually mature features found in attractive faces. In this study, we investigated whether baby schema features in adult faces affect not only cuteness, but also beauty and attractiveness. We also investigated possible differences among attractiveness, beauty, and cuteness, and possible effects of perceived youth on these judgments. Results showed that baby schema features affected judgments of attractiveness, beauty, and cuteness, but that perceived youth did not significantly influence these judgments. Furthermore, the effect of each facial feature differed across rating types with the participants' naïve interpretation of rating categories. This suggests that beauty predominantly refers to sexual attraction, while attractiveness refers to a non-sexual attraction regardless of participants' gender. However, gender differences may exist in judging cuteness. Therefore, expressions related to attractiveness may incorporate different elements and this distinction may not be fully shared across gender.

Individual differences in autistic traits predict the perception of direct gaze for males, but not for females.

Despite the emphasis of autism spectrum disorders as a continuum of atypical social behaviors and the sexual heterogeneity of phenotypic manifestations, whether gaze processing constitutes an autistic endophenotype in both sexes remains unclear. Using the Autism-Spectrum Quotient and a psychophysical approach in a normal population (N = 128), here we demonstrated that individual differences in autistic traits predicted direct-gaze perception for males, but not for females. Our findings suggest that direct-gaze perception may not constitute an autistic endophenotype in both sexes, and highlight the importance of sex differences when considering relationships between autistic traits and behaviors.

Helmholtz illusion makes you look fit only when you are already fit, but not for everyone.

A square filled with horizontal stripes is perceived as thinner than one with vertical stripes (Helmholtz illusion). This is not consistent with a common belief that horizontally striped clothing makes a person look fatter, and studies on this problem have shown inconsistent results. Here, we demonstrate three factors that could have complicated the issue. First, the Helmholtz effect is stronger for a thin figure than for a fat one, with possible reversal for the latter. Second, we found large variability across participants, suggesting dependence on features to attend. Third, there was strong hysteresis as to the order of testing fat and thin figures, suggesting the effect of surrounding people in daily life. There can be yet other factors, but we should note that this apparently simple case of application of a geometrical illusion in daily perception should be taken as a rather complex phenomenon.