Pupillary evidence reveals the influence of positive thoughts on brightness perception

Our visual experience often varies based on momentary thoughts and feelings. For example,when positive thoughts are invoked, visual objects may appear brighter. However, it remainsunclear whether this phenomenological experience is driven by a genuine top-down modulation of brightness perception or by a mere response bias. To investigate this issue, here we use pupillometry as a more objective measure of perceived brightness. We asked participants to judge the brightness level of an iso-luminant gray color patch after evaluating the valence of a positive or negative word. We found that the gray color patch elicited greater pupillary light reflex and more frequent “bright” responses after observers had evaluated the valence of a positive word. As pupillary light reflex is unlikely driven by voluntary control or response bias, these results suggest that positive concepts can genuinely modulate brightness perception.

G0 Revisited as Equally Bright Reference Boundary

Brilliance and zero grayness (denoted as G0) and are two terms coined by Ralph Evans. Nayatani, Heckaman and Fairchild have done series of work to incorporate them into comprehensive color appearance models. In this work, those concepts were reexamined to scale lightness/brightness across the chromaticity diagram. Specifically, observers, mostly with a color science background, were asked to adjust the luminance of a color patch to appear with no grayness, or equivalently just about/cease to glow. The hypothesis was that lightness can be equalized across those chromaticities and the Helmholtz-Kohlrausch effect is automatically incorporated. This hypothesis was verified in a follow-up experiment where another group of observers completed paired comparisons of the brightness between the collected G0 results. The G0 task was also repeated under another two levels of adaption backgrounds, based on which different absolute brightness results for a given chromaticity might be derived. In addition, high correlations between the G0 results (as a perceptual boundary between appearance modes) and different physical gamut boundaries including MacAdam's optimal colors were found for possible computational proxies and ecologically meaningful implications.

Lichen Aureus with Dermoscopic Findings: A case report

Lichen aureus is a rare variant of pigmented purpuric dermatosis, which often affects young adults and is localized mainly on the lower extremities. We present here a 31-year-old female who had a solitary golden-brown-color patch on her right leg for 1 year. Punch biopsy of the lesion revealed lymphohistiocytic band-like infiltrate of the papillary dermis with erythrocyte extravasation and hemosiderin deposits. The diagnosis of Lichen aureus was made based on clinicopathologic findings. The dermoscopic findings that support this diagnosis were brownish yellow diffuse coloration of the background, round to oval red dots, globules and patches and twisted red loops. Herein, we present the dermoscopic findings of a 31-year-old female patient with a diagnosis of lichen aureus established with clinical and histopathological features. Keywords: pigmented purpuric dermatosis, lichen aureus, dermoscopy

Crossmodal Correspondences in the Sounds of Chinese Instruments

People tend to associate stimuli from different sensory modalities, a phenomenon known as crossmodal correspondences. We conducted two experiments to investigate how Chinese participants associated musical notes produced by four types of Chinese instruments (bowed strings, plucked strings, winds, and percussion instruments) with different colors, taste terms, and fabric textures. Specifically, the participants were asked to select a sound to match each color patch or taste term in Experiment 1 and to match the experience of touching each fabric in Experiment 2. The results demonstrated some associations between pitch and color, taste term, or the smoothness of fabrics. Moreover, certain types of Chinese instruments were preferentially chosen to match some of the colors, taste terms, and the texture of certain fabrics. These findings therefore provided insights about the perception of Chinese music and shed light on how to apply the multisensory features of sounds to enhance the composition, performance, and appreciation of music.

Orange Is Less Than Green: An Examination of Bidirectionality in Grapheme-Color Synesthesia

Grapheme-color synesthetes experience a sense of color when viewing graphemes (e.g., digits and letters). Traditionally, these synesthetic perceptions are considered to be unidirectional, where viewing a grapheme elicits a nonveridical sensation of color, but viewing a color does not induce a reciprocal sense of a grapheme. A growing body of research has emerged that suggests the potential for bidirectional percepts, wherein color facilitates additional grapheme perception. We present here a novel paradigm in which we presented two sets of pure color patches, based on synesthete’s reported colors, side-by-side and asked participants to indicate the color patch with the greater affiliated magnitude. Results indicated that the odds of answering correctly on trials were significantly greater for synesthetes (80.2% accuracy) than nonsynesthetes (52.1% accuracy). These results are aligned with other reports that support the notion of inducing a sense of magnitude from color in synesthetes. These findings challenge the traditional model of synesthesia as a unidirectional phenomenon and have implications of the neuronal communications that underlie perception in general.

The representation of colored objects in macaque color patches

An important question about color vision is: how does the brain represent the color of an object? The recent discovery of “color patches” in macaque inferotemporal (IT) cortex, the part of brain responsible for object recognition, makes this problem experimentally tractable. Here we record neurons in three color patches, middle color patch CLC (central lateral color patch), and two anterior color patches ALC (anterior lateral color patch) and AMC (anterior medial color patch), while presenting images of objects systematically varied in hue. We found that all three patches contain high concentrations of hue-selective cells, and the three patches use distinct computational strategies to represent colored objects: while all three patches multiplex hue and shape information, shape-invariant hue information is much stronger in anterior color patches ALC/AMC than CLC; furthermore, hue and object shape specifically for primate faces/bodies are over-represented in AMC but not in the other two patches.

Modification of Happiness Expression in Face Images

This article describes how facial expression detection and adjustment in complex psychological aspects of vision is central to a number of visual and cognitive computing applications. This article presents an algorithm for automatically estimating happiness expression of face images whose demographic aspects like race, gender and eye direction are changeable. The method is also broadening for alteration of level of happiness expression for face images. A schema of the weighted modification is proposed for enhancement of happiness expression. The authors employ a robust face representation which combines the color patch similarity and the self-resemblance of image patches. A large set of face images with appearance of the properties is learned in a statistical model for interpreting the facial expression of happiness. The authors will show the experiments of such a model using face features for learning by SVM and analyze the performance.