The role of expertise in the aesthetic evaluation of mathematical equations

Movement synchrony among dance performers predicts brain synchrony among dance spectators

Performing dance is an intrinsically social art form where at least one person moves while another person watches. Dancing in groups promotes social bonding, but how does group dance affect the people watching? A group of dancers and dance novices watched a 30 min dance video individually in an fMRI scanner. In a follow-up behavioural study, the same people watched the video again and provided continuous enjoyment ratings. Firstly, we computed cross-recurrence of continuous enjoyment ratings and inter-subject correlations (ISCs) in fMRI separately for both groups, and with the choreographer of the dance work. At both behavioural and neural levels, dancers responded more similarly to each other than novices. ISCs among dancers extended beyond brain areas involved in audio-visual integration and sensory areas of human movement perception into motor areas, suggesting greater sensorimotor familiarity with the observed dance movements in the expert group. Secondly, we show that dancers' brain activations and continuous ratings are more similar to the choreographer's ratings in keeping with sharing an aesthetic and artistic perspective when viewing the dance. Thirdly, we show that movement synchrony among performers is the best predictor of brain synchrony among both expert and novice spectators. This is consistent with the idea that changes in emergent movement synchrony are a key aesthetic feature of performing dance. Finally, ISCs across perceptual and motor brain areas were primarily driven by movement acceleration and synchrony, whereas ISCs in orbital and pre-frontal brain areas were overall weaker and better explained by the continuous enjoyment ratings of each group. Our findings provide strong evidence that the aesthetic appreciation of dance involves a common experience between dance spectators and the choreographer. Moreover, the similarity of brain activations and of enjoyment increases with shared knowledge of - and practice in - the artform that is being experienced, in this case contemporary performing dance.

Modelling individual aesthetic judgements over time

Listening to music, watching a sunset-many sensory experiences are valuable to us, to a degree that differs significantly between individuals, and within an individual over time. We have theorized (Brielmann & Dayan 2022 Psychol. Rev. 129, 1319-1337 (doi:10.1037/rev0000337))) that these idiosyncratic values derive from the task of using experiences to tune the sensory-cognitive system to current and likely future input. We tested the theory using participants' (n = 59) ratings of a set of dog images (n = 55) created using the NeuralCrossbreed morphing algorithm. A full realization of our model that uses feature representations extracted from image-recognizing deep neural nets (e.g. VGG-16) is able to capture liking judgements on a trial-by-trial basis (median r = 0.65), outperforming predictions based on population averages (median r = 0.01). Furthermore, the model's learning component allows it to explain image sequence dependent rating changes, capturing on average 17% more variance in the ratings for the true trial order than for simulated random trial orders. This validation of our theory is the first step towards a comprehensive treatment of individual differences in evaluation. This article is part of the theme issue 'Art, aesthetics and predictive processing: theoretical and empirical perspectives'.