Explicit action perception shares resources with music syntax: A controlled behavioral study

Given evidence that neural resources monitoring language syntax also underlie the perception of music syntax (Koelsch, 2005) and recently a proposed ‘syntax’ in sequential action (Fazio et al., 2009), a previous EEG study investigated whether neural resources may be shared between implicit perception of music and action (Sammler et al., 2010). Results yielded a syntactic-like ERP pattern elicited by the errors in sequential action, but no interaction of resources across the music and action domains. The present follow-up study sought behavioral signs of resource-overlap when perception is instead explicit. Five chords accompanied five reach-to-grasp images in a 2x2 factorial interference paradigm (target: regular/irregular cadence paired with correct/incorrect grasp). Results indeed revealed an interaction of resources which monitored the action and music sequences, manifested in task accuracy. A control experiment with accompanying pure tones instead of chords (standard/deviant final tone) did not, however, show the same interaction. Crucially, the null-result control study speaks to a neural resource involved in action perception that is shared only with syntactically organized sound, not a simple auditory distraction. This promising behavioral data warrants follow-up neuropsychological experimentation with explicit-task paradigms

PSS21 The Cost-Effectiveness of Intravitreal Aflibercept (IVT-AFL) in Treating Neovascular Age-Related Macular Degeneration in an Italian Setting

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Digital LED Pixels: Instructions for use and a characterization of their properties

This article details how to control light emitting diodes (LEDs) using an ordinary desktop computer. By combining digitally addressable LEDs with an off-the-shelf microcontroller (Arduino), multiple LEDs can be controlled independently and with a high degree of temporal, chromatic, and luminance precision. The proposed solution is safe (can be powered by a 5-V battery), tested (has been used in published research), inexpensive (∼ $60 +$2 per LED), highly interoperable (can be controlled by any type of computer/operating system via a USB or Bluetooth connection), requires no prior knowledge of electrical engineering (components simply require plugging together), and uses widely available components for which established help forums already exist. Matlab code is provided, including a ‘minimal working example’ of use suitable for use by beginners. Properties of the recommended LEDs are also characterized, including their response time, luminance profile, and color gamut. Based on these, it is shown that the LEDs are highly stable in terms of both luminance and chromaticity, and do not suffer from issues of warm-up, chromatic shift, and slow response times associated with traditional CRT and LCD monitor technology

Selective Influences of Precision and Power Grips on Speech Categorization

Peer reviewe

Joint action aesthetics

Synchronized movement is a ubiquitous feature of dance and music performance. Much research into the evolutionary origins of these cultural practices has focused on why humans perform rather than watch or listen to dance and music. In this study, we show that movement synchrony among a group of performers predicts the aesthetic appreciation of live dance performances. We developed a choreography that continuously manipulated group synchronization using a defined movement vocabulary based on arm swinging, walking and running. The choreography was performed live to four audiences, as we continuously tracked the performers’ movements, and the spectators’ affective responses. We computed dynamic synchrony among performers using cross recurrence analysis of data from wrist accelerometers, and implicit measures of arousal from spectators’ heart rates. Additionally, a subset of spectators provided continuous ratings of enjoyment and perceived synchrony using tablet computers. Granger causality analyses demonstrate predictive relationships between synchrony, enjoyment ratings and spectator arousal, if audiences form a collectively consistent positive or negative aesthetic evaluation. Controlling for the influence of overall movement acceleration and visual change, we show that dance communicates group coordination via coupled movement dynamics among a group of performers. Our findings are in line with an evolutionary function of dance–and perhaps all performing arts–in transmitting social signals between groups of people. Human movement is the common denominator of dance, music and theatre. Acknowledging the time-sensitive and immediate nature of the performer-spectator relationship, our study makes a significant step towards an aesthetics of joint actions in the performing arts

Passive sensorimotor stimulation triggers long lasting alpha-band fluctuations in visual perception

Movement planning and execution rely on the anticipation and online control of the incoming sensory input. Evidence suggests that sensorimotor processes may synchronize visual rhythmic activity in preparation of action performance. Indeed, we recently reported periodic fluctuations of visual contrast sensitivity that are time-locked to the onset of an intended movement of the arm. However, the origin of the observed visual modulations has so far remained unclear because of the endogenous (and thus temporally undetermined) activation of the sensorimotor system that is associated with voluntary movement initiation. In this study, we activated the sensorimotor circuitry involved in the hand control in an exogenous and controlled way by means of peripheral stimulation of the median nerve and characterized the spectrotemporal dynamics of the ensuing visual perception. The stimulation of the median nerve triggers robust and long-lasting (∼1 s) alpha-band oscillations in visual perception, whose strength is temporally modulated in a way that is consistent with the changes in alpha power described at the neurophysiological level after sensorimotor stimulation. These findings provide evidence in support of a causal role of the sensorimotor system in modulating oscillatory activity in visual areas with consequences for visual perception

Alpha-band cortico-muscular coherence predicts visual sensitivity

Brain oscillations are now recognized to have a key role in regulating cortical excitability and orchestrating the interactions between relevant populations of neurons. Recent evidence suggests that oscillations-based mechanisms may structure sensorimotor integration in humans. Here, we exploited the ongoing oscillations that can be measured in the motor output (i.e., in the force) as a window into the central motor rhythms. We recorded EEG/EMG activity while participants (n=20) performed continuous isometric contraction with their right hand for 5 s; at random times during hand contraction, we briefly (16 ms) presented a visual flash at the individual luminance threshold and participants had to report whether they had seen or not seen the stimulus (50-50%, hits-misses). We found that hand force fluctuates at ~10 Hz, which is commonly reported as the main frequency of physiological tremor. This rhythm is coupled (phase coherent) with an EEG alpha rhythm, with the central rhythm driving the peripheral one. Remarkably, just before stimulus presentation (~200 ms), brainforce alpha phase synchronization is significantly stronger for hits compared to misses. Visual perception is thus not only dependent on the oscillatory activity in sensory areas but on its continuous, dynamic interplay with the ongoing motor activity. These findings outline a new andpromising view on the intimate interconnection between sensory and motor functions and its possible neurophysiological substrate