Neuroarchitecture of musical emotions

La respuesta emocional ante la música, o emoción musical, es una respuesta universal que depende de diferentes procesos psicológicos y recluta una extensa red de estructuras neuronales. Mediante el empleo de técnicas como la electroencefalografía, la resonancia magnética funcional y los estudios con población clínica e individuos con formación musical previa, se ha empezado a dilucidar estos mecanismos cerebrales. El objetivo de este artículo es hacer una revisión de los trabajos más relevantes en los que se identifican los correlatos neuronales de la emoción musical, desde los procesos más automáticos hasta los más complejos, y comprender cómo interaccionan en el cerebro. En concreto, se describe cómo la presentación de música emocional está asociada a una respuesta rápida en estructuras talámicas y subtalámicas, acompañada por cambios electrodérmicos y endocrinos. También se explica que el procesamiento de la emoción musical implica la activación de la corteza auditiva y estructuras límbicas y paralímbicas, como la amígdala, la corteza cingulada anterior o el hipocampo, lo que demuestra la contribución del sistema límbico a la emoción musical. Asimismo, se detalla cómo la emoción musical depende de los significados semántico y sintáctico de la música, procesados en áreas temporales y parietofrontales, respectivamente. Además, se mencionan trabajos recientes que han demostrado cómo los mecanismos de simulación emocional también contribuyen a la emoción musical. Por último, se hace un resumen de estos trabajos, comentando sus limitaciones y ofreciendo alternativas para seguir avanzando en el estudio de la neuroarquitectura de la emoción musical

Dance as a Subject for Empirical Aesthetics

The purpose of this paper is to highlight the possibilities that research on dance appreciation offers empirical aesthetics, as well as the challenges it poses. Behavioral and neuroimaging approaches have, to date, mainly focused on the perception and recognition of human body movement and structure. A small number of studies, nonetheless, have explicitly taken the basic research on the perceptual, emotional and cognitive processes engaged during movement observation, together with their neural concomitants, as a starting point to understand the aesthetic experience triggered by the observation of a dance. We provide an overview of these studies and, thereafter, point out avenues for future research on dance appreciation within the scope of empirical aesthetics. We also note some methodological and conceptual issues that should be taken into account in the design of empirical studies of the aesthetic appreciation of dance, including dance theory scholarship and humanistic approaches to dance practice. Finally, we describe how common movement features of dance styles around the world suggest that humans may be endowed with an evolved cognitive ability to appreciate and to be aesthetically moved by dance

Modulation of motor cortex activity in a visual working memory task of hand images

Recent studies suggest that brain regions engaged in perception are also recruited during the consolidation interval of the percept in working memory (WM). Evidence for this comes from studies showing that maintaining arbitrary visual, auditory, and tactile stimuli in WM elicits recruitment of the corresponding sensory cortices. Here we investigate if encoding and WM maintenance of visually perceived body-related stimuli engage just visual regions, or additional sensorimotor regions that are classically associated with embodiment processes in studies of body and action perception. We developed a novel WM paradigm in which participants were asked to remember body and control non-body-related images. In half of the trials, visual-evoked activity that was time-locked to the sight of the stimuli allowed us to examine visual processing of the stimuli to-be-remembered (visual-only trials). In the other half of the trials we additionally elicited a task irrelevant key pressing during the consolidation interval of the stimuli in WM. This manipulation elicited motor-cortical potentials (MCPs) concomitant to visual processing (visual-motor trials). This design allowed us to dissociate motor activity depicted in the MCPs from concurrent visual processing by subtracting activity from the visual-only trials to the compound activity found in the visual-motor trials. After dissociating the MCPs from concomitant visual activity, the results show that only the body-related images elicited neural recruitment of sensorimotor regions over and above visual effects. Importantly, the number of body stimuli to-be-remembered (memory load) modulated this later motor cortical activity. The current observations link together research in embodiment and WM by suggesting that neural recruitment is driven by the nature of the information embedded in the percept

Persistent recruitment of somatosensory cortex during active maintenance of hand images in working memory

Working memory (WM) supports temporary maintenance of task-relevant information. This process is associated with persistent activity in the sensory cortex processing the information (e.g., visual stimuli activate visual cortex). However, we argue here that more multifaceted stimuli moderate this sensory-locked activity and recruit distinctive cortices. Specifically, perception of bodies recruits somatosensory cortex (SCx) beyond early visual areas (suggesting embodiment processes). Here we explore persistent activation in processing areas beyond the sensory cortex initially relevant to the modality of the stimuli. Using visual and somatosensory evoked-potentials in a visual WM task, we isolated different levels of visual and somatosensory involvement during encoding of body and non-body-related images. Persistent activity increased in SCx only when maintaining body images in WM, whereas visual/posterior regions' activity increased significantly when maintaining non-body images. Our results bridge WM and embodiment frameworks, supporting a dynamic WM process where the nature of the information summons specific processing resources

Dance Expertise modulates behavioural and psychophysiological responses to affective body movement

The present study shows how motor expertise increases sensitivity to affective body movement at the behavioural and physiological level. Nineteen affective movement experts (professional ballet dancers) and twenty-four controls watched 96 video clips of emotionally expressive body movements while they performed an affect rating task (subjective response) and their galvanic skin response was recorded (psychophysiological response). The movements in the clips were either sad or happy, and in half of the trials movements were played in the order in which they are learned (forward presentation), and in the other half, backwards (control condition). Results showed that motor expertise in affective body movement specifically modulated both behavioural and physiological sensitivity to others’ affective body movement, and that this sensitivity is particularly strong when movements are shown in the way they are learnt (forward presentation). The evidence is discussed within current theories of proprioceptive arousal feedback and motor simulation accounts

Episodic Recollection Difficulties in ASD Result from Atypical Relational Encoding: Behavioral and Neural Evidence

Memory functioning in Autism Spectrum Disorder (ASD) is characterized by impairments in the encoding of relational but not item information and difficulties in the recollection of contextually rich episodic memories but not in the retrieval of relatively context-free memories through processes of familiarity. The neural underpinnings of this profile and the extent to which encoding difficulties contribute to retrieval difficulties in ASD remain unclear. Using a paradigm developed by Addis and McAndrews [2006; Neuroimage, 33, 1194-1206] we asked adults with and without a diagnosis of ASD to study word-triplets during functional Magnetic Resonance Imaging (fMRI) scanning that varied in the number of category relations amongst component words. Performance at test confirmed attenuated recollection in the context of preserved familiarity based retrieval in ASD. The results also showed that recollection but not familiarity based retrieval increases as a function of category relations in word triads for both groups, indicating a close link between the encoding of relational information and recollection. This link was further supported by the imaging results, where blood oxygen level dependent (BOLD) signal responses in overlapping regions of the inferior prefrontal cortex were sensitive to the relational encoding manipulation as well as the contrast between recollection versus familiarity based retrieval. Interestingly, however, there was no evidence of prefrontal signal differentiation for this latter contrast in the ASD group for whom signal changes in a left hippocampal region were also marginally attenuated. Together, these observations suggest that attenuated levels of episodic recollection in ASD are, at least in part, attributable to anomalies in relational encoding processes

Revealing the body in the brain: an ERP method to examine sensorimotor activity during visual perception of body-related information

Examining the processing of others’ body-related information in the perceivers’ brain across the neurotypical and clinical population is a key topic in the domain of cognitive neurosciences. We argue that beyond classical neuroimaging techniques and frequency analyses, methods that can be easily adapted to capture the fast processing of body-related information in the brain are needed. Here we introduce a novel method that allows this by measuring event-related potentials recorded with electroencephalography (ERPs-EEG). This method possesses known EEG advantages (low cost, high temporal resolution, established paradigms) plus an improvement of its main limitation; i.e., spatiotemporally smoothed resolution due to mixed neural sources. This occurs when participants are presented and process images of bodies/actions that recruit posterior visual cortices. Such stimulus-evoked activity may spread and contaminate the recording of simultaneous activity arising from sensorimotor brain areas, which also process body-related information. Therefore, it is difficult to dissociate the contributing role of different brain regions. To overcome this, we propose eliciting a combination of somatosensory, motor, and visual-evoked potentials during processing of body-related information (vs. non-body-related). Next, brain activity from sensorimotor and visual systems can be dissociated by subtracting activity from trials containing only visual-evoked potentials to those trials containing either a mixture of visual and somatosensory or visual and motor-cortical potentials. This allows isolating visually driven neural activity in areas other than visual. To introduce this method, we revise recent work using this method, consider the processing of body-related stimuli in the brain, as well as outline key methodological aspects to-be-considered. This work provides a clear guideline to researchers interested or transitioning from behavioural to ERPs studies, offering the possibility to adapt well-established paradigms in the EEG realm to study others’ body-related processing in the perceiver’s own cortical body representation (e.g., examining classical EEG components in the social and embodiment frameworks)

Interoceptive impairments do not lie at the heart of Autism or Alexithymia

Background: Quattrocki and Friston (2012) argued that abnormalities in interoception–the process of representing one’s internal physiological states–could lie at the heart of autism, because of the critical role interoception plays in the ontogeny of social-affective processes. This proposal drew criticism from proponents of the alexithymia hypothesis, who argue that social-affective and underlying interoceptive impairments are not a feature of autism per se, but of alexithymia (a condition characterised by difficulties describing and identifying one's own emotions), which commonly co-occurs with autism. Despite the importance of this debate for our understanding of ASD, and of the role of interoceptive impairments in psychopathology more generally, direct empirical evidence is scarce and inconsistent. Methods: Experiment 1 examined in a sample of 137 neurotypical individuals the association among autistic traits, alexithymia, and interoceptive accuracy on a standard heartbeat tracking measure of interoceptive accuracy. In Experiment 2, interoceptive accuracy was assessed in 46 adults with ASD (27 of whom had clinically-significant alexithymia) and 48 neurotypical adults. Results: Experiment 1 confirmed strong associations between autistic traits and alexithymia, but yielded no evidence to suggest that either was associated with interoceptive difficulties. Similarly, Experiment 2 provided no evidence for interoceptive impairments in autistic adults, irrespective of any co-occurring alexithymia. Bayesian analyses consistently supported the null hypothesis. Conclusions: The observations pose a significant challenge to notions that interoceptive impairments constitute a core feature of either ASD or alexithymia, at least as far as the direct perception of interoceptive signals is concerned. General scientific summary: This article suggests that impairments in interoception–the process of representing one’s internal physiological states–do not lie at the heart of either autism or alexithymia

Searching for bodies: ERP evidence for independent somatosensory processing during visual search for body-related information

Attention allows us to select relevant information by modulating neural activity within sensory brain areas processing that information. Previous research has shown that visual perception of body stimuli recruits visual cortices together with observer's body representation in somatosensory cortex, which is known for processing body-related information (e.g., haptics, kinematics). However, whether attentional selection of visual body stimuli involves just visual or additional somatosensory areas remains elusive. Here we elicited visual and somatosensory evoked activity during a visual search task, whereby participants searched for target hand images defined by either visual (colour) or bodily (posture) features. In line with previous studies, we found electrophysiological evidence for attentional selection over visual areas (i.e., N2pc) regardless of the feature type. Importantly, after dissociating somatosensory from visual evoked activity, we show that only attentional selection of hand posture - but not hand colour - elicits modulation of somatosensory evoked electrocortical activity over somatosensory cortex. This suggests that attention may not only modulate cortical activity associated with the input-sensory modality (in this case, visual), but, depending on the type of attended information, it may also modulate cortical activity associated with another task-relevant sensory modality (in this case, somatosensory). Overall, our results provide evidence for a flexible attention mechanism that operates according to specific behavioural goals and the information embedded in the percept