Can we really 'read' art to see the changing brain? A review and empirical assessment of clinical case reports and published artworks for systematic evidence of quality and style changes linked to damage or neurodegenerative disease.

The past three decades have seen multiple reports of people with neurodegenerative disorders, or other forms of changes in their brains, who also show putative changes in how they approach and produce visual art. Authors argue that these cases may provide a unique body of evidence, so-called 'artistic signatures' of neurodegenerative diseases, that might be used to understand disorders, provide diagnoses, be employed in treatment, create patterns of testable hypotheses for causative study, and also provide unique insight into the neurobiological linkages between the mind, brain, body, and the human penchant for art-making itself. However-before we can begin to meaningfully build from such emerging findings, much less formulate applications-not only is such evidence currently quite disparate and in need of systematic review, almost all case reports and artwork ratings are entirely subjective, based on authors' personal observations or a sparse collection of methods that may not best fit underlying research aims. This leads to the very real question of whether we might actually find patterns of systematic change if fit to a rigorous review-Can we really 'read' art to illuminate possible changes in the brain? How might we best approach this topic in future neuroscientific, clinical, and art-related research? This paper presents a review of this field and answer to these questions. We consider the current case reports for seven main disorders-Alzheimer's and Parkinson's disease, frontotemporal and Lewy body dementia, corticobasal degeneration, aphasia, as well as stroke-consolidating arguments for factors and changes related to art-making and critiquing past methods. Taking the published artworks from these papers, we then conduct our own assessment, employing computerized and human-rater-based approaches, which we argue represent best practice to identify stylistic or creativity/quality changes. We suggest, indeed, some evidence for systematic patterns in art-making for specific disorders and also find that case authors showed rather high agreement with our own assessments. More important, through opening this topic and past evidence to a systematic review, we hope to open a discussion and provide a theoretical and empirical foundation for future application and research on the intersection of art-making and the neurotypical, the changed, and the artistic brain.

The differential power of extraneous influences to modify aesthetic judgments of biological and artifactual stimuli.

We addressed the question of the extent to which external information is capable of modifying aesthetic ratings given to two different categories of stimuli-images of faces (which belong to the biological category) and those of abstract paintings with no recognizable objects (which sit in the artifactual category). A total of 51 participants of different national origins rated the beauty of both sets of stimuli, indicating the certainty of their rating; they then re-rated them after being exposed to the opinions of others on their aesthetic status. Of these 51 participants, 42 who met our criteria were selected to complete the experiment. The results showed that individuals were less prone to modifying their ratings of stimuli belonging to the biological category compared to those falling into the artifactual category. We discuss this finding in light of our theoretical Bayesian-Laplacian model and on the evidence given by previous empirical research.

Parkinson's disease and changes in the appreciation of art: A comparison of aesthetic and formal evaluations of paintings between PD patients and healthy controls.

Parkinson's disease (PD) is a progressing neurodegenerative disease predominantly involving the loss of dopamine producing neurons with hallmark symptoms of motor disorders and cognitive, motivational, emotional, and perceptual impairments. Intriguingly, PD can also be connected-often anecdotally-with a sudden burst of artistic creativity, motivation, or changed quality/style of produced art. This has led to growing empirical interest, promising a window into brain function and the unique neurological signature of artists. This topic also fits a growing interest from researchers in other areas, including Alzheimer's or other dementia, which have suggested that specific changes in art production/appraisal may provide a unique basis for therapy, diagnosis, or understanding of these diseases. However, whether PD also shows similar impacts on how we perceive and evaluate art has never been systematically addressed. We compared a cohort of PD patients against age-matched healthy controls, asking participants to rate paintings using scales of liking and beauty and terms pertaining to artworks' formal and conceptual qualities previously designed to provide a rubric for symptom identification. We found no evidence for PD-related differences in liking or beauty. However, PD patients showed higher ratings on assessed "emotionality," potentially relating to the tie between PD, dopamine pathways, and emotion/reward.

Why would Parkinson's disease lead to sudden changes in creativity, motivation, or style with visual art?: A review of case evidence and new neurobiological, contextual, and genetic hypotheses.

Parkinson's disease (PD) is a devastating diagnosis with, however, potential for an extremely intriguing aesthetic component. Despite motor and cognitive deficits, an emerging collection of studies report a burst of visual artistic output and alterations in produced art in a subgroup of patients. This provides a unique window into the neurophysiological bases for why and how we might create and enjoy visual art, as well as into general brain function and the nature of PD or other neurodegenerative diseases. However, there has not been a comprehensive organization of literature on this topic. Nor has there been an attempt to connect case evidence and knowledge on PD with present understanding of visual art making in psychology and neuroaesthetics in order to propose hypotheses for documented artistic changes. Here, we collect the current research on this topic, tie this to PD symptoms and neurobiology, and provide new theories focusing on dopaminergic neuron damage, over-stimulation from dopamine agonist therapy, and context or genetic factors revealing the neurobiological basis of the visual artistic brain.

Does priming negative emotions really contribute to more positive aesthetic judgments? A comparative study of emotion priming paradigms using emotional faces versus emotional scenes and multiple negative emotions with fEMG.

An outstanding question in empirical aesthetics concerns whether negative emotions (e.g., fear, disgust) can improve aesthetic judgments of liking. Although negative emotions are sometimes linked with enjoyment in music or visual design/art, emotion priming studies have shown conflicting results, reporting both more negative and more positive assessments. These divergences may be driven by key differences in priming procedures. Specifically, past studies' use of either emotional faces or emotional scenes as primes as well as differing negative emotion content (fear, disgust) may involve differing processes leading to opposing effects, particularly in aesthetic judgments. To differentiate among these, we presented emotion primes (20 ms) consisting of either emotional faces or scenes, further subdivided in disgusting, fearful, neutral, or positive emotional content and tested how liking, valence, and arousal ratings of abstract patterns were affected. Additionally, facial electromyography (fEMG) over M. frontalis (indicator of fear), M. levator labii (disgust), and M. zygomaticus (positive) muscles was recorded, to see whether primes would elicit prime-emotion congruent changes. However, fEMG activations indicated no prime congruent changes. Critically, primes influenced ratings in an emotion congruent manner in both faces and emotional scenes. Stimuli were rated as more liked and positively valenced after positive primes and less liked/more negatively valenced after fear or disgust primes. The similarity of priming effects in both prime types in absence of congruent fEMG changes may suggest that priming exerts its influence via a cognitive rather than a more immediate emotional route. Overall-at least in emotional priming-negative emotions seem to be incompatible with higher liking. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Neuropsychopharmacological aesthetics: A theoretical consideration of pharmacological approaches to causative brain study in aesthetics and art.

Recent developments in neuroaesthetics have heightened the need for causative approaches to more deeply understand the mechanism underlying perception, emotion, and aesthetic experiences. This has recently been the topic for empirical work, employing several causative methods for changing brain activity, as well as comparative assessments of individuals with brain damage or disease. However, one area of study with high potential, and indeed a long history of often nonscientific use in the area of aesthetics and art, employing psychopharmacological chemicals as means of changing brain function, has not been systematically utilized. This chapter reviews the literature on this topic, analyzing neuroendocrinological (neurochemical) approaches and mechanisms that might be used to causatively study the aesthetic brain. We focus on four relevant neuromodulatory systems potentially related to aesthetic experience: the dopaminergic, serotonergic, cannabinoid, and the opioidergic system. We build a bridge to psychopharmacological methods and review drug-induced behavioral and neurobiological consequences. We conclude with a discussion of hypotheses and suggestions for future research.

The experience of beauty derived from sorrow.

We studied the neural mechanisms that are engaged during the experience of beauty derived from sorrow and from joy, two experiences that share a common denominator (beauty) but are linked to opposite emotional valences. Twenty subjects viewed and rerated, in a functional magnetic resonance imaging scanner, 120 images which each had classified into the following four categories: beautiful and sad; beautiful and joyful; neutral; ugly. The medial orbito-frontal cortex (mOFC) was active during the experience of both types of beauty. Otherwise, the two experiences engaged different parts of the brain: joyful beauty engaged areas linked to positive emotions while sorrowful beauty engaged areas linked to negative experiences. Separate regions of the cerebellum were engaged during experience of the two conditions. A functional connectivity analysis indicated that the activity within the mOFC was modulated by the supplementary motor area/middle cingulate cortex, known to be engaged during empathetic experiences provoked by other peoples' sadness. Hum Brain Mapp 38:4185-4200, 2017. © 2017 Wiley Periodicals, Inc.

Empathy as a guide for understanding the balancing of Distancing-Embracing with negative art.

We connect the Distancing-Embracing model to theoretical and empirical evidence regarding empathy, which raises questions about the ordering and modulation of distancing in particular. Namely, distancing may not be a binary, continuously on/off process. Rather we suggest that changes in distancing as actualized via the relation between the individual and art (e.g., through empathy) might be a useful avenue for further consideration.

A neurobiological enquiry into the origins of our experience of the sublime and beautiful.

Philosophies of aesthetics have posited that experience of the sublime-commonly but not exclusively derived from scenes of natural grandeur-is distinct from that of beauty and is a counterpoint to it. We wanted to chart the pattern of brain activity which correlates with the declared intensity of experience of the sublime, and to learn whether it differs from the pattern that correlates with the experience of beauty, reported in our previous studies (e.g., Ishizu and Zeki, 2011). 21 subjects participated in a functional magnetic resonance imaging experiment. Prior to the experiment, they viewed pictures of landscapes, which they rated on a scale of 1-5, with 5 being the most sublime and 1 being the least. This allowed us to select, for each subject, five sets of stimuli-from ones experienced as very sublime to those experienced as not at all sublime-which subjects viewed and re-rated in the scanner while their brain activity was imaged. The results revealed a distinctly different pattern of brain activity from that obtained with the experience of beauty, with none of the areas active with the latter experience also active during experience of the sublime. Sublime and beautiful experiences thus appear to engage separate and distinct brain systems.

Varieties of perceptual instability and their neural correlates.

We report experiments designed to learn whether different kinds of perceptually unstable visual images engage different neural mechanisms. 21 subjects viewed two types of bi-stable images while we scanned the activity in their brains with functional magnetic resonance imaging (fMRI); in one (intra-categorical type) the two percepts remained within the same category (e.g. face-face) while in the other (cross-categorical type) they crossed categorical boundaries (e.g. face-body). The results showed that cross- and intra-categorical reversals share a common reversal-related neural circuitry, which includes fronto-parietal cortex and primary visual cortex (area V1). Cross-categorical reversals alone engaged additional areas, notably anterior cingulate cortex and superior temporal gyrus, which have been posited to be involved in conflict resolution.

Distinct neural mechanisms of tonal processing between musicians and non-musicians.

OBJECTIVE: Both behavioral and neural responses to deviant melody endings can be enhanced through musical training. Yet it is unknown whether there are any differences in the neural responses of musicians and non-musicians given no difference in their behavioral responses. It is also unknown whether the melody preceding the fixed final tone influences the sense of completion. METHODS: We recorded neuromagnetic responses in ten musicians and ten non-musicians while they were evaluating the sense of completion associated with melodies. RESULTS: The sense of a melody's completion was influenced by the combination of the preceding melody and the ending tones. The N1 had shorter latency in musicians, while the sustained field had larger amplitudes in non-musicians. CONCLUSIONS: Musicians and non-musicians rated the sense of completion similarly, yet neural responses differed between the groups. SIGNIFICANCE: These findings suggest that neural processes in musicians and non-musicians may be distinct even when the sense of completion is assessed similarly in both groups. In other words, there might be specific tonal processing available to non-musicians which can compensate for their lack of musical training.

The "Visual Shock" of Francis Bacon: an essay in neuroesthetics.

In this paper we discuss the work of Francis Bacon in the context of his declared aim of giving a "visual shock."We explore what this means in terms of brain activity and what insights into the brain's visual perceptive system his work gives. We do so especially with reference to the representation of faces and bodies in the human visual brain. We discuss the evidence that shows that both these categories of stimuli have a very privileged status in visual perception, compared to the perception of other stimuli, including man-made artifacts such as houses, chairs, and cars. We show that viewing stimuli that depart significantly from a normal representation of faces and bodies entails a significant difference in the pattern of brain activation. We argue that Bacon succeeded in delivering his "visual shock" because he subverted the normal neural representation of faces and bodies, without at the same time subverting the representation of man-made artifacts.

Disambiguation of ambiguous figures in the brain.

Disambiguation refers to the ability to interpret ambiguous information in a sensible way, which is important in an ever-changing external environment. Disambiguation occurs when prior knowledge is given before an ambiguous stimulus is presented. For example, labeling a series of meaningless blobs as a "human body" can change the observer's perception. The aim of this experiment was to study the neural circuitry underlying disambiguation caused by prior knowledge. We presented to participants a series of meaningless blobs with different contextual information. As participants performed this task, we used magnetoencephalography to map the brain areas that were activated when participants perceived blobs as a human body. The participants were presented identical sets of blob stimuli, and were instructed that a human body would appear more frequently in the "high body" condition than in the "low body" condition. We found the blob stimuli were more frequently perceived as the human body when they were presented in the "high body" condition. Such contextual modulation correlated with activity in the extrastriate body area (EBA) and the inferior frontal gyrus (IFG). Furthermore, we observed that IFG activation preceded EBA activation. These findings suggest that top-down processing in the IFG plays a role in disambiguating ambiguous information and modifying an individual's perceptions.

Toward a brain-based theory of beauty.

We wanted to learn whether activity in the same area(s) of the brain correlate with the experience of beauty derived from different sources. 21 subjects took part in a brain-scanning experiment using functional magnetic resonance imaging. Prior to the experiment, they viewed pictures of paintings and listened to musical excerpts, both of which they rated on a scale of 1-9, with 9 being the most beautiful. This allowed us to select three sets of stimuli--beautiful, indifferent and ugly--which subjects viewed and heard in the scanner, and rated at the end of each presentation. The results of a conjunction analysis of brain activity showed that, of the several areas that were active with each type of stimulus, only one cortical area, located in the medial orbito-frontal cortex (mOFC), was active during the experience of musical and visual beauty, with the activity produced by the experience of beauty derived from either source overlapping almost completely within it. The strength of activation in this part of the mOFC was proportional to the strength of the declared intensity of the experience of beauty. We conclude that, as far as activity in the brain is concerned, there is a faculty of beauty that is not dependent on the modality through which it is conveyed but which can be activated by at least two sources--musical and visual--and probably by other sources as well. This has led us to formulate a brain-based theory of beauty.

Magnetoencephalographic study of the neural responses in body perception.

A fundamental trait of human beings is the ability to discern information communicated by others. The human body is one of the important sources of such information. To date, several researchers have reported two body-selective regions in the brain-the extrastriate body area (EBA) and fusiform body area. As compared to the number of studies on spatial distribution, studies on the temporal processing of body perception are few. The electroencephalography (EEG) findings of a recent study indicate that observation of the human body induces a remarkable response leading to the generation of event-related-potentials that peak at 190 ms. However, source localization by using EEG has limitations. The advantage of magnetoencephalography (MEG) is that it enables localization of cortical activities and has excellent temporal resolution. In this study, we used MEG to measure the neural responses underlying the perception of the human body. Our results suggest that cortical activation induced by body images was observed in the bilateral EBA region with a latency of 190 ms and right-hemispheric dominance. Our study revealed the regions involved and the latency differences between these regions in body perception. Further, our results show the usefulness of MEG for body perception studies and suggest that like the face, the body plays a unique role in the human recognition process.

Effects of motor imagery on intermanual transfer: a near-infrared spectroscopy and behavioural study.

Intermanual transfer is the ability that previous studies by one limb promote the later learning by the other limb. This ability has been demonstrated in various effectors and types of training. Motor imagery, the mental simulation of motor execution, is believed to be strongly associated with the cognitive aspects of motor execution, and the pattern of brain activity during motor imagery is similar to that of motor execution, although the activation pattern is smaller, and the level is lower. If the cognitive component of motor execution strongly contributes to transfer, the training effect of motor imagery would be expected to transfer to the contralateral limb. In the present study, we used the tapping sequence paradigm to evaluate the occurrence of intermanual transfer through motor imagery and to compare differences of transfer effects to motor execution learning. We divided participants into three groups: an execution group, a motor imagery group and a no-training control group. Before and after a nondominant left hand training session, ipsilateral hand tests were conducted. After the post-test, a contralateral right-hand test was also conducted. In order to investigate the relationship between transfer effect and neural activation during the learning phase, we measured motor-related brain area activity using near-infrared spectroscopy (NIRS). Execution was effective especially for trained movement, imagery was effective for both trained movement and intermanual transfer. Brain activity suggesting predictive transfer differed between two groups, suggesting that motor execution and motor imagery training have different behavioural effects and neural contributions.

Motor activity and imagery modulate the body-selective region in the occipital-temporal area: a near-infrared spectroscopy study.

The extrastriate body area (EBA) lies in the occipital-temporal cortex and has been described as a "body-selective" region that responds when viewing other people's bodies. Recently, several studies have reported that EBA is also modulated when the subject moves or imagines moving their own body, even without visual feedback. The present study involved 3 experiments, wherein the first experiment was conducted to examine whether near-infrared spectroscopy (NIRS) could capture any activity in the EBA when viewing images of bodies. The second experiment was designed to elucidate whether this region also responds when the subjects move their own body, and the third to observe whether imagining carrying out a movement would activate EBA. Images of human bodies and chairs were used as the stimuli for the first experiment, simple hand movements carried out by the subject were used for the second and the act of imagining hand movements for the third. Our results confirmed that the region we defined as EBA was clearly activated when the subject viewed images of human bodies, carried out movements of their own body and imagined moving parts of their own body, thus demonstrating the usefulness of NIRS as a new brain imaging method. Moreover, we found a gender-based difference when imagining movement; male subjects showed a greater response than female subjects. This may reflect a gender difference in imagery skills; however, further research is needed to verify this hypothesis.