Ecological decoding of visual aesthetic preference with oscillatory electroencephalogram features-A mini-review.

In today's digital information age, human exposure to visual artifacts has reached an unprecedented quasi-omnipresence. Some of these cultural artifacts are elevated to the status of artworks which indicates a special appreciation of these objects. For many persons, the perception of such artworks coincides with aesthetic experiences (AE) that can positively affect health and wellbeing. AEs are composed of complex cognitive and affective mental and physiological states. More profound scientific understanding of the neural dynamics behind AEs would allow the development of passive Brain-Computer-Interfaces (BCI) that offer personalized art presentation to improve AE without the necessity of explicit user feedback. However, previous empirical research in visual neuroaesthetics predominantly investigated functional Magnetic Resonance Imaging and Event-Related-Potentials correlates of AE in unnaturalistic laboratory conditions which might not be the best features for practical neuroaesthetic BCIs. Furthermore, AE has, until recently, largely been framed as the experience of beauty or pleasantness. Yet, these concepts do not encompass all types of AE. Thus, the scope of these concepts is too narrow to allow personalized and optimal art experience across individuals and cultures. This narrative mini-review summarizes the state-of-the-art in oscillatory Electroencephalography (EEG) based visual neuroaesthetics and paints a road map toward the development of ecologically valid neuroaesthetic passive BCI systems that could optimize AEs, as well as their beneficial consequences. We detail reported oscillatory EEG correlates of AEs, as well as machine learning approaches to classify AE. We also highlight current limitations in neuroaesthetics and suggest future directions to improve EEG decoding of AE.

Cross-subject aesthetic preference recognition of Chinese dance posture using EEG.

Due to the differences in knowledge, experience, background, and social influence, people have subjective characteristics in the process of dance aesthetic cognition. To explore the neural mechanism of the human brain in the process of dance aesthetic preference, and to find a more objective determining criterion for dance aesthetic preference, this paper constructs a cross-subject aesthetic preference recognition model of Chinese dance posture. Specifically, Dai nationality dance (a classic Chinese folk dance) was used to design dance posture materials, and an experimental paradigm for aesthetic preference of Chinese dance posture was built. Then, 91 subjects were recruited for the experiment, and their EEG signals were collected. Finally, the transfer learning method and convolutional neural networks were used to identify the aesthetic preference of the EEG signals. Experimental results have shown the feasibility of the proposed model, and the objective aesthetic measurement in dance appreciation has been implemented. Based on the classification model, the accuracy of aesthetic preference recognition is 79.74%. Moreover, the recognition accuracies of different brain regions, different hemispheres, and different model parameters were also verified by the ablation study. Additionally, the experimental results reflected the following two facts: (1) in the visual aesthetic processing of Chinese dance posture, the occipital and frontal lobes are more activated and participate in dance aesthetic preference; (2) the right brain is more involved in the visual aesthetic processing of Chinese dance posture, which is consistent with the common knowledge that the right brain is responsible for processing artistic activities.

The contour effect: Differences in the aesthetic preference and stress response to photo-realistic living environments.

The interest in the response to contours has recently re-emerged, with various studies suggesting a universal preference for curved over angular stimuli. Although no consensus has yet been reached on the reasons for this preference, similar effects have been proposed in interior environments. However, the scarcely available research primarily depends on schematic or unmatched stimuli and faces heterogeneity in the reported results. In a within-subject design, we investigated the claimed contour effect in photo-realistic indoor environments using stimulus material previously tested in virtual reality (VR). A total of 198 online participants rated 20 living room images, exclusively manipulated on the contours (angular vs. curved) and style (modern vs. classic) levels. The scales represented aesthetic (beauty and liking) and stress (rest and stress) responses. Beyond our main focus on contours, we additionally examined style and sex effects to account for potential interactions. Results revealed a significant main effect of contours on both aesthetic (η2 g = 1-2%) and stress (η2 g = 8-12%) ratings. As expected, images of curved (vs. angular) contours scored higher on beauty, liking, and rest scales, and lower on stress. Regarding interactions with style, curvature was aesthetically preferred over angularity only within images depicting modern interiors, however, its positive effect on stress responses remained significant irrespective of style. Furthermore, we observed sex differences in aesthetic but not in stress evaluations, with curvature preference only found in participants who indicated female as their sex. In sum, our study primarily confirms positive effects of curvature, however, with multiple layers. First, the impact on aesthetic preference seems to be influenced by individual and contextual factors. Second, in terms of stress responses, which might be especially relevant for designs intended to promote mental-health, the consistent effects suggest a more generalizable, potentially biophilic characteristic of curves. To the best of our knowledge, this is the first study to demonstrate these effects in fully-matched, photo-realistic, and multi-perspective interior design stimuli. From the background of a previous VR trial from our research group, whereby the same rooms did not elicit any differences, our findings propose that static vs. immersive presentations might yield different results in the response to contours.

Aesthetic Preference for Negatively-Valenced Artworks Remains Stable in Pathological Aging: A Comparison Between Cognitively Impaired Patients With Alzheimer's Disease and Healthy Controls.

Background: Despite severe cognitive dysfunction in Alzheimer's disease (AD), aesthetic preferences in AD patients seem to retain some stability over time, similarly to healthy controls. However, the underlying mechanisms of aesthetic preference stability in AD remain unclear. We therefore aimed to study the role of emotional valence of stimuli for stability of aesthetic preferences in patients with AD compared to cognitively unimpaired elderly adults. Methods: Fifteen AD patients (Mini-Mental State Examination (MMSE) score 12-26) without visual impairment and/or psychiatric disorder, as well as 15 healthy controls without cognitive impairment (MMSE ≥ 27) matched in age, sex, art interest and highest level of education were included in this study. All participants were asked to rank-order eight artworks per stimulus category (positive, negative, neutral in emotional valence) according to their preference twice with a 2-week span in-between. Based on these two rankings a preference change score was calculated. In order to assess explicit recognition memory of the artworks in the second testing session, four artworks of each stimulus category used in the preference ranking task were presented together with a content-matched distractor artwork painted by the same artist. Participants had to indicate which of the stimuli they had seen 2 weeks previously. Results: AD patients [MMSE (M) = 18.9 ± 3.6; Age (M) = 85.4 ± 6.9; 33.3% male] had no explicit recognition memory of the artworks (recognition at chance level), whereas healthy controls [MMSE (M) = 27.7 ± 1.4; Age (M) = 84.3 ± 6.7; 33.3% male] correctly recognized 85% of stimuli after 2 weeks. AD patients had equally stable preferences compared to the control group for negative artworks, but less stable preferences for positive and neutral images (Bonferroni-corrected significance levels; p < 0.017). Conclusion: Even in cognitively impaired AD patients, aesthetic preference for negatively-valenced artworks remains relatively stable. Our study provides novel evidence that AD patients may have a somewhat preserved implicit valence system for negative compared to neutral or positive visual information, especially in the domain of aesthetics. However, more studies need to further uncover the details of the underlying neurocognitive mechanisms of preference stability in pathological aging.

Aesthetics of musical timing: Culture and expertise affect preferences for isochrony but not synchrony.

Expressive communication in the arts often involves deviations from stylistic norms, which can increase the aesthetic evaluation of an artwork or performance. The detection and appreciation of such expressive deviations may be amplified by cultural familiarity and expertise of the observer. One form of expressive communication in music is playing "out of time," including asynchrony (deviations from synchrony between different instruments) and non-isochrony (deviations from equal spacing between subsequent note onsets or metric units). As previous research has provided somewhat conflicting perspectives on the degree to which deviations from synchrony and isochrony are aesthetically relevant, we aimed to shed new light on this topic by accounting for the effects of listeners' cultural familiarity and expertise. We manipulated (a)synchrony and (non-)isochrony separately in excerpts from three groove-based musical styles (jazz, candombe, and jembe), using timings from real performances. We recruited musician and non-musician participants (N = 176) from three countries (UK, Uruguay, and Mali), selected to vary in their prior experience of hearing and performing these three styles. Participants completed both an aesthetic preference rating task and a perceptual discrimination task for the stimuli. Our results indicate an overall preference toward synchrony in these styles, but culturally contingent, expertise-dependent preferences for deviations from isochrony. This suggests that temporal processing relies on mechanisms that vary in their dependence on low-level and high-level perception, and emphasizes the role of cultural familiarity and expertise in shaping aesthetic preferences.

Research on the Healing Potential of Rural Community Streets From the Perspective of Audiovisual Integration: A Case Study of Four Rural Communities in China.

Rural communities have become a hot topic in academic circles because of their graceful natural environment and great healing potential. However, existing research still lacks attention to the street space in rural communities and rarely considers its integrated visual and soundscape design in terms of their effect on public health. As a result, the healing potential of rural community streets cannot be fully used in design practice. Relevant audiovisual materials were collected from a field investigation in four rural communities in southwestern China. Based on these data, the subjective and objective healing index data of subjects under comprehensive audiovisual conditions were collected and analyzed through laboratory experiments. The results revealed that type of street space affects healing potential, and the artificial-natural enclosed and natural semi-enclosed streets are the street types with the best healing effect. When the total sound pressure level was 55dB(A), the sound combination with birdsong accounting for 70% had a significant positive effect on improving the healing effect of rural community streets. In contrast, the sound combination with birdsong accounting for 50% or less had no significant effect on improving healing. The subjective healing perception of street space in rural communities was significantly positively correlated with aesthetic preferences. There was also a significant correlation between subjective healing perception and physiological index data in the audiovisual combination. This research explored the impact of different types of street space and sound combinations on the healing effect of rural community streets in an integrated audiovisual environment and provided a scientific basis for the healing landscape design of rural community streets in an integrated audiovisual environment. It was expected to provide new ideas for the construction of rural community landscapes, including acoustic landscapes, to promote physical and mental healing.

Is Mate Preference Recognizable Based on Electroencephalogram Signals? Machine Learning Applied to Initial Romantic Attraction.

Initial romantic attraction (IRA) refers to a series of positive reactions toward potential ideal partners based on individual preferences; its evolutionary value lies in facilitating mate selection. Although the EEG activities associated with IRA have been preliminarily understood; however, it remains unclear whether IRA can be recognized based on EEG activity. To clarify this, we simulated a dating platform similar to Tinder. Participants were asked to imagine that they were using the simulated dating platform to choose the ideal potential partner. Their brain electrical signals were recorded as they viewed photos of each potential partner and simultaneously assessed their initial romantic attraction in that potential partner through self-reported scale responses. Thereafter, the preprocessed EEG signals were decomposed into power-related features of different frequency bands using a wavelet transform approach. In addition to the power spectral features, feature extraction also accounted for the physiological parameters related to hemispheric asymmetries. Classification was performed by employing a random forest classifier, and the signals were divided into two categories: IRA engendered and IRA un-engendered. Based on the results of the 10-fold cross-validation, the best classification accuracy 85.2% (SD = 0.02) was achieved using feature vectors, mainly including the asymmetry features in alpha (8-13 Hz), beta (13-30 Hz), and theta (4-8 Hz) rhythms. The results of this study provide early evidence for EEG-based mate preference recognition and pave the way for the development of EEG-based romantic-matching systems.

The effect of visual attention process and thinking styles on environmental aesthetic preference: An eye-tracking study.

People often form different aesthetic preferences for natural and built environments, which affects their behavioral intention; however, it remains unknown whether this difference in aesthetic preference is due to differences in thinking styles. However, whether tourists' aesthetic preferences differ when using different visual attention processes has not been studied further. This study used eye-tracking and self-reporting to investigate these questions. The results show that natural environment images are more favored visually because they can evoke in tourists larger pupil diameters and longer scan paths, but we found no significant difference in fixation duration and fixation counts. We also found that the scanning path of tourists who predominantly rely on intuitive thinking is modulated by the bottom-up attention process, while the scanning path of tourists who prefer rational thinking is modulated by the top-down attention process. In the bottom-up process, tourists who prefer rational thinking exhibit more positive aesthetic preferences and emotional arousal. In summary, the present study verified that aesthetic preference is more likely to be influenced by both thinking style and visual attention processing. The results of the present work provide preliminary evidence that the aesthetic preference of the environment is not only related to visual attention but also affected by the individual visual attention process and thinking style.

The impact of action observation and motor imagery on the aesthetic preference of Chinese calligraphy.

The creation of artwork requires motor activity. However, few empirical studies have directly explored the relationship between the experience of an artist's action and aesthetic experience. This study aimed to examine the effect of observing and imagery of the artist's action on the participants' aesthetic preferences. In Experiment 1 and 2, we took hard-pen and brush-pen Chinese calligraphy images as the stimulus, respectively, to explore the influence of action observation on the aesthetic preference by manipulating the artists' actions. The results of both Experiment 1 and 2 show that when participants observed the artists' actions, they tended to report a higher preference for calligraphy images compared with the control condition. In Experiments 3 and 4, we used instructions to manipulate the motor imagery tasks and investigated the effect of imaging the artist's action on the participants' aesthetic preferences. The results showed that both kinesthetic imagery and visual imagery increased the participants' preference. In general, our study shows that both action observation and motor imagery contribute to participants' aesthetic preferences. The results are discussed in terms of how artists' actions possibly influence the aesthetic preference of Chinese calligraphy.

The Implicit Aesthetic Preference for Mobile Marketing Interface Layout-An ERP Study.

Businesses and scholars have been trying to improve marketing effect by optimizing mobile marketing interfaces aesthetically as users browse freely and aimlessly through mobile marketing interfaces. Although the layout is an important design factor that affects interface aesthetics, whether it can trigger customer's aesthetic preferences in mobile marketing remains unexplored. To address this issue, we employ an empirical methodology of event-related potentials (EPR) in this study from the perspective of cognitive neuroscience and psychology. Subjects are presented with a series of mobile marketing interface images of different layouts with identical marketing content. Their EEG waves were recorded as they were required to distinguish a target stimulus from the others. After the experiment, each of the subjects chose five stimuli interfaces they like and five they dislike. By analyzing the ERP data derived from the EEG data and the behavioral data, we find significant differences between the disliked interfaces and the other interfaces in the ERP component of P2 from the frontal-central area in the 200-400 ms post-stimulus onset time window and LPP from both the frontal-central and parietal-occipital area in the 400-600 ms time window. The results support the hypothesis that humans do make rapid implicit aesthetic preferences for interface layouts and suggest that even under a free browsing context like the mobile marketing context, interface layouts that raise high emotional arousal can still attract more user attention and induce users' implicit aesthetic preference.

Effects of Visual Attributes of Flower Borders in Urban Vegetation Landscapes on Aesthetic Preference and Emotional Perception.

The vegetation landscape in urban green space has been shown to provide great psychological benefits to people. Flower border is a well-designed small-scale vegetation landscape with the advantages of color and vegetation richness. This study focused on the effects of the visual attributes of flower borders on the aesthetic preference and emotional perception. The face recognition measurement method was used to obtain the emotional perception and the questionnaire survey method was used to measure the aesthetic preference. The results indicated the following: (1) regarding the 'color features' factor, high proportions of cool color and green vegetation significantly increased aesthetic preference and emotional valence, while the proportion of warm color had a negative effect on valence; (2) the 'visual attractiveness' (color brightness, and visual richness) and 'color configuration' (number of plant patches and number of color hues) factor was positively associated with aesthetic preference and emotional valence; (3) aesthetic preference was significantly related to emotional valence; (4) males expressed higher aesthetic preference and valence for flower border images than females. The results are expected to improve the aesthetic quality of flower borders and to promote public emotional health through the effective design of urban vegetation landscapes.

The effect of action observation on aesthetic preference of Chinese calligraphy: An fMRI study.

INTRODUCTION: There is some evidence suggesting that movement perception has an effect on aesthetic experience. However, the neural mechanisms underlying the observation of creators' creative action (the process that calligraphers create calligraphy) remain unclear. METHODS: In this study, participants were scanned with fMRI while performing aesthetic judgments on Chinese calligraphy images with/without action observation. RESULTS: Behavioral results showed that both the work by the expert and novice with action observation were rated significantly higher on aesthetic preference than those without action observation. Imaging results showed that brain regions associated with perceptual, cognitive, and emotional processing were commonly activated by calligraphy images with/without action observation. However, compared with no action observation, aesthetic judgments of calligraphy images with action observation elicited stronger activation in the anterior cingulate cortex and the bilateral insula. Meanwhile, the superior parietal lobe which is associated with relevant inner action imitation, was also activated when observing the creator's action. CONCLUSIONS: Brain activation in the superior parietal lobe, anterior cingulate cortex, and the bilateral insula indicated that observing the creative action of the creators contributed to the aesthetic experience of the observer.

An independent contribution of colour to the aesthetic preference for paintings.

Walking around an art museum we can see how colours influence our aesthetic preferences: many great works of art would not be as impressive in grey scales. Is the beauty of colours in abstract paintings anchored to the spatial composition of the paintings, or can it be preserved even with random spatial arrangements? To test whether colour can have an independent contribution to aesthetic appreciation, we asked participants to select the preferred image among pairs of colour-manipulated versions of the same painting. We changed hue, but preserved lightness and saturation, by rotating the colour volume around the L* axis in CIELAB space. To test the influence of the spatial structure, the images of the paintings were presented: (1) in their original format, (2) spatially scrambled but preserving the colour composition, and (3) in a control condition with both colour and spatial scrambling. Relative preference as a function of hue angle was obtained for the four paintings in their original and modified forms. For the original paintings, we found that participants generally preferred the colour angles that matched the original version of the paintings. Crucially, participants preferred the same colour distributions for spatially scrambled paintings as for the original paintings. For the control condition, there were no preferred colour configurations. This suggests that the aesthetic preference of colours in our abstract paintings is not anchored to particular spatial compositions, but is at least partly preserved even when the spatial composition is destroyed. Paintings thus can contain an aesthetic component that is exclusively related to colour.

Individual Differences in Aesthetic Preferences for Multi-Sensorial Stimulation.

The aim of the current project was to investigate aesthetics in multi-sensorial stimulation and to explore individual differences in the process. We measured the aesthetics of interactive objects (IOs) which are three-dimensional objects with electronic components that exhibit an autonomous behaviour when handled, e.g., vibrating, playing a sound, or lighting-up. The Q-sorting procedure of Q-methodology was applied. Data were analysed by following the Qmulti protocol. The results suggested that overall participants preferred IOs that (i) vibrate, (ii) have rough surface texture, and (iii) are round. No particular preference emerged about the size of the IOs. When making an aesthetic judgment, participants paid more attention to the behaviour variable of the IOs than the size, contour or surface texture. In addition, three clusters of participants were identified, suggesting that individual differences existed in the aesthetics of IOs. Without proper consideration of potential individual differences, aesthetic scholars may face the risk of having significant effects masked by individual differences. Only by paying attention to this issue can more meaningful findings be generated to contribute to the field of aesthetics.

The Perceptual and Aesthetic Aspects of the Music-Paintings Congruence.

The purpose of the present study is to investigate the effect of congruence between music and paintings on the aesthetic preference of paintings. Congruence was specified as the similarity in perceived regularity and the complexity of jazz compositions and abstract paintings (the ratings of regularity and complexity in both sets of stimuli were obtained in the pilot study). In the main experiment, 32 participants rated the aesthetic pleasantness of paintings with congruent, incongruent, and no music background. In addition, they rated the music-paintings matching (how well the music goes with the painting). The results show no effect of congruence on aesthetic pleasantness ratings. The effect on the perceived matching was significant; matching is higher in the congruent compared to the incongruent condition. These findings suggest that congruency has a strong effect on the perceptual aspect of the music-paintings compatibility (visuo-auditory similarity) and no effect on the aesthetic aspect (liking).

Like what you see: Generalization of social learning determines art appreciation.

We examine whether a stimulus generalization framework can provide insight in how experience shapes evaluative responses to artworks. Participants received positive information about one artwork and negative information about another artwork. Afterwards, we tested their evaluative responses not only to these artworks but also to similar artworks, which allowed us to assess generalization. Results showed that the artwork that was paired with positive information and the artwork that was similar to it were evaluated more positively than the other artworks. These findings confirm that theories that aim to explain art appreciation could benefit from taking learning and its generalization into account.

The sound of beauty: How complexity determines aesthetic preference.

Stimulus complexity is an important determinant of aesthetic preference. An influential idea is that increases in stimulus complexity lead to increased preference up to an optimal point after which preference decreases (inverted-U pattern). However, whereas some studies indeed observed this pattern, most studies instead showed an increased preference for more complexity. One complicating issue is that it remains unclear how to define complexity. To address this, we approached complexity and its relation to aesthetic preference from a predictive coding perspective. Here, low- and high-complexity stimuli would correspond to low and high levels of prediction errors, respectively. We expected participants to prefer stimuli which are neither too easy to predict (low prediction error), nor too difficult (high prediction error). To test this, we presented two sequences of tones on each trial that varied in predictability from highly regular (low prediction error) to completely random (high prediction error), and participants had to indicate which of the two sequences they preferred in a two-interval forced-choice task. The complexity of each tone sequence (amount of prediction error) was estimated using entropy. Results showed that participants tended to choose stimuli with intermediate complexity over those of high or low complexity. This confirms the century-old idea that stimulus complexity has an inverted-U relationship to aesthetic preference.

Body Aesthetic Preference in Preschoolers and Attraction to Canons Violation: An Exploratory Study.

Sensitivity to canons of beauty as represented in the human body-and as typically defined in the Western Culture-has been poorly studied in children. Current literature shows that infants as young as about three months are sensitive to the human body structure and its parts. Using a sample of 54 three- to five-year-old children, the present study investigated preference for drawings representing the "canonical" body structure, contrasting these with drawings showing the same bodies, but where the relation between trunk and legs was modified. It was hypothesized that preference for the canonical body structures would emerge as early as three years, increasing with age. Results only partially supported the hypothesis: while three-year-olds showed a significant preference for the canonical body structures as predicted, a significant preference reversal was found for the four-year-olds, with a tendency to return to preferring the canonical body at five years. The results are discussed in light of research findings associated with developmental theories hallmarking visual art perception in children.

Image Feature Types and Their Predictions of Aesthetic Preference and Naturalness.

Previous research has investigated ways to quantify visual information of a scene in terms of a visual processing hierarchy, i.e., making sense of visual environment by segmentation and integration of elementary sensory input. Guided by this research, studies have developed categories for low-level visual features (e.g., edges, colors), high-level visual features (scene-level entities that convey semantic information such as objects), and how models of those features predict aesthetic preference and naturalness. For example, in Kardan et al. (2015a), 52 participants provided aesthetic preference and naturalness ratings, which are used in the current study, for 307 images of mixed natural and urban content. Kardan et al. (2015a) then developed a model using low-level features to predict aesthetic preference and naturalness and could do so with high accuracy. What has yet to be explored is the ability of higher-level visual features (e.g., horizon line position relative to viewer, geometry of building distribution relative to visual access) to predict aesthetic preference and naturalness of scenes, and whether higher-level features mediate some of the association between the low-level features and aesthetic preference or naturalness. In this study we investigated these relationships and found that low- and high- level features explain 68.4% of the variance in aesthetic preference ratings and 88.7% of the variance in naturalness ratings. Additionally, several high-level features mediated the relationship between the low-level visual features and aaesthetic preference. In a multiple mediation analysis, the high-level feature mediators accounted for over 50% of the variance in predicting aesthetic preference. These results show that high-level visual features play a prominent role predicting aesthetic preference, but do not completely eliminate the predictive power of the low-level visual features. These strong predictors provide powerful insights for future research relating to landscape and urban design with the aim of maximizing subjective well-being, which could lead to improved health outcomes on a larger scale.

The colors of paintings and viewers' preferences.

One hypothesis to explain the aesthetics of paintings is that it depends on the extent to which they mimic natural image statistics. In fact, paintings and natural scenes share several statistical image regularities but the colors of paintings seem generally more biased towards red than natural scenes. Is the particular option for colors in each painting, even if less naturalistic, critical for perceived beauty? Here we show that it is. In the experiments, 50 naïve observers, unfamiliar with the 10 paintings tested, could rotate the color gamut of the paintings and select the one producing the best subjective impression. The distributions of angles obtained are described by normal distributions with maxima deviating, on average, only 7 degrees from the original gamut orientation and full width at half maximum just above the threshold to perceive a chromatic change in the paintings. Crucially, for data pooled across observers and abstract paintings the maximum of the distribution was at zero degrees, i.e., the same as the original. This demonstrates that artists know what chromatic compositions match viewers' preferences and that the option for less naturalistic colors does not constrain the aesthetic value of paintings.