Perception of Vibrotactile Cues in Musical Performance

We suggest that studies on active touch psychophysics are needed to inform the design of haptic musical interfaces and better understand the relevance of haptic cues in musical performance. Following a review of the previous literature on vibrotactile perception in musical performance, two recent experiments are reported. The first experiment investigated how active finger-pressing forces affect vibration perception, finding significant effects of vibration type and force level on perceptual thresholds. Moreover, the measured thresholds were considerably lower than those reported in the literature, possibly due to the concurrent effect of large (unconstrained) finger contact areas, active pressing forces, and long-duration stimuli. The second experiment assessed the validity of these findings in a real musical context by studying the detection of vibrotactile cues at the keyboard of a grand and an upright piano. Sensitivity to key vibrations in fact not only was highest at the lower octaves and gradually decreased toward higher pitches; it was also significant for stimuli having spectral peaks of acceleration similar to those of the first experiment, i.e., below the standard sensitivity thresholds measured for sinusoidal vibrations under passive touch conditions

Neural correlates of audiovisual motion capture

Visual motion can affect the perceived direction of auditory motion (i.e., audiovisual motion capture). It is debated, though, whether this effect occurs at perceptual or decisional stages. Here, we examined the neural consequences of audiovisual motion capture using the mismatch negativity (MMN), an event-related brain potential reflecting pre-attentive auditory deviance detection. In an auditory-only condition occasional changes in the direction of a moving sound (deviant) elicited an MMN starting around 150 ms. In an audiovisual condition, auditory standards and deviants were synchronized with a visual stimulus that moved in the same direction as the auditory standards. These audiovisual deviants did not evoke an MMN, indicating that visual motion reduced the perceptual difference between sound motion of standards and deviants. The inhibition of the MMN by visual motion provides evidence that auditory and visual motion signals are integrated at early sensory processing stages

Concepts and the `new' empiricism

This article examines the role of concepts in the so-called 'new' empiricism that is currently emerging from the writings of Gilles Deleuze. It asks what concepts are, and how they might be put to work to present the 'pure difference' of the empirical world. In addressing these questions, a number of parallels and contrasts are drawn between the writings of Deleuze and Max Weber. It is shown that many of Deleuze's key arguments about concepts- in particular, that they are pedagogical, multiple, networked and problem-oriented in basis - are anticipated by Weber's sociological methodology of concept formation. This leads, finally, to a consideration of whether the creation of concepts as a practice belongs primarily within the domain of philosophy (as argued by Deleuze), or if it is a key part of social scientific work more generally