Comparison of two methods of hue scaling.

Hue-scaling functions are designed to characterize color appearance by assessing the relative strength of the red versus green and blue versus yellow opponent sensations comprising different hues. However, these judgments can be non-intuitive and may pose difficulties for measurement and analysis. We explored an alternative scaling method based on positioning a dial to represent the relative similarity or distance of each hue from the labeled positions for the opponent categories. The hue-scaling and hue-similarity rating methods were compared for 28 observers. Settings on both tasks were comparable though the similarity ratings showed less inter-observer variability and weaker categorical bias, suggesting that these categorical biases may reflect properties of the task rather than the percepts. Alternatively, properties that are concordant for the two paradigms provide evidence for characteristics that do reflect color appearance. Individual differences on both tasks suggest that color appearance depends on multiple, narrowly tuned color processes, which are inconsistent with conventional color-opponent theory.

Age, pupil size differences, and color choices for the "dress" and the "jacket".

The color identification responses to photographs of #thedress (white/gold and blue/black) and a jacket (white/blue and green/black, and teal) reveal obvious individual differences in color perception. To explore possible association between pupil size/retinal illuminance and color perception, we recorded the pupil diameters of participants shown 22 uniformly colored (generated from the RGB values using a laptop LCD display) screens followed by photographs of #thedress and jacket. We analyzed (a) pupil size difference in the color groups and (b) age-related pupil size and/or reflex change and its influence on color perception. The data confirms that the average pupil size of the white/gold group was significantly less than the blue/black group for the dress. The pupil size difference between the color groups is slightly higher in the 21-30-year and 31-55-year age groups but not in the 18-20-year age group, while a similar variance was not observed for the jacket color groups. Interestingly, the average pupil size of both color groups was smaller for the dress compared to the baseline (collected with a gray hue displayed on the screen), whereas an opposite effect was observed for the jacket. The contrasting results for the two photographs do not allow for a strong inference of only pupil size change principal for differences in color perception. But, a probable explanation of the pupil size difference could be the subjective variation in the perceptual interpretation of illumination cues in the photographs.

Do normal pupil diameter differences in the population underlie the color selection of #thedress?

The fundamental question that arises from the color conundrum of #thedress is "What are the phenomena that underlie the individual differences in the reported colors when all other conditions like light and device for the display are identical?" A survey of 384 participants showed near-equal distribution into blue/black (b/b) and white/gold (w/g) groups. We looked at pupil size differences in a sample population of 53 individuals from these two groups and a group that switched from w/g to b/b. Our results showed that the w/g and switch groups had significantly lower pupil size than the b/b group (w/g

An Exploratory Investigation of Functional Network Connectivity of Empathy and Default Mode Networks in a Free-Viewing Task.

This study reports dynamic functional network connectivity (dFNC) analysis on time courses of putative empathy networks-cognitive, emotional, and motor-and the default mode network (DMN) identified from independent components (ICs) derived by the group independent component analysis (ICA) method. The functional magnetic resonance imaging (fMRI) data were collected from 15 subjects watching movies of three genres, an animation (S1), Indian Hindi (S2), and a Hollywood English (S3) movie. The hypothesis of the study is that empathic engagement in a movie narrative would modulate the activation with the DMN. The clippings were individually rated for emotional expressions, context, and empathy self-response by the fMRI subjects post scanning and by 40 participants in an independent survey who rated at four time intervals in each clipping. The analysis illustrates the following: (a) the ICA method separated ICs with areas reported for empathy response and anterior/posterior DMNs. An IC indicating insula region activation reported to be crucial for the emotional empathy network was separated for S2 and S3 movies only, but not for S1, (b) the dFNC between DMN and ICs corresponding to cognitive empathy network showed higher positive periodical fluctuating correlations for all three movies, while ICs with areas crucial to motor or emotional empathy display lower positive or negative correlation values with no distinct periodicity. A possible explanation for the lower values and anticorrelation between the DMN and emotional empathy networks could possibly be inhibition due to internal self-reflections, attributed to DMN, while processing and preparing a response to external emotional content. The positive higher correlation values for cognitive empathy networks may reflect a functional overlap with DMN for enhanced internal self-reflections, inferring beliefs and intentions about the 'other', all triggered by the external stimuli. The findings are useful in the study of deviations in functional synergies of large complex networks associated with empathy responses and DMN in clinical applications like autism and schizophrenia.

Evidence of stimulus correlated empathy modes--Group ICA of fMRI data.

The analysis of the cognitive processes in response to a narrative as presented in a movie provides an insight into momentary reaction to a single depicted action like a facial expression and an aggregate processing of the entire sequence of events. In this study we report results from fMRI data analyzed by group independent component analysis (ICA) method from a free viewing experiment using a diverse set of movie clips--an animation, a Hollywood and an Indian Hindi movie. The fMRI data were collected from 15 college students as they viewed 5-8 min clips from three movies. The movie clips were rated for depiction of emotional expressions, the emotion as per the narrative and the viewer's own empathy response. The neural correlates attributed to cognitive, motor and emotional empathy were the focus of the study. The methodology of using long duration stimuli in free viewing mode combined with ICA analysis has the potential to tease out spatially distributed but temporally coherent brain activity as demonstrated in this study. The independent components obtained from group ICA method isolated spatial maps with activations which can be safely ascribed to stimulus processing. We found that the activity in the areas attributable to cognitive and motor empathy was comparable for all the three stimuli while certain critical areas for emotional empathy were not noticed for the animation movie. These findings lead to interesting questions on possible differential emotion response in viewer(s) for computer generated actors compared to actors in live-action movies and the role of narrative and exposure to different genre of movies on racial, ethnic and cultural differences in empathy response.