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Deep brain stimulation (DBS) for Parkinson's disease (PD) is an established advanced therapy that produces therapeutic effects through high frequency stimulation. Although this therapeutic option leads to improved clinical outcomes, the mechanisms of the underlying efficacy of this treatment are not well understood. Therefore, investigation of DBS and its postoperative effects on brain architecture is of great interest. Diffusion weighted imaging (DWI) is an advanced imaging technique, which has the ability to estimate the structure of white matter fibers; however, clinical application of DWI after DBS implantation is challenging due to the strong susceptibility artifacts caused by implanted devices. This study aims to evaluate the feasibility of generating meaningful white matter reconstructions after DBS implantation; and to subsequently quantify the degree to which these tracts are affected by post-operative device-related artifacts. DWI was safely performed before and after implanting electrodes for DBS in 9 PD patients. Differences within each subject between pre- and post-implantation FA, MD, and RD values for 123 regions of interest (ROIs) were calculated. While differences were noted globally, they were larger in regions directly affected by the artifact. White matter tracts were generated from each ROI with probabilistic tractography, revealing significant differences in the reconstruction of several white matter structures after DBS. Tracts pertinent to PD, such as regions of the substantia nigra and nigrostriatal tracts, were largely unaffected. The aim of this study was to demonstrate the feasibility and clinical applicability of acquiring and processing DWI post-operatively in PD patients after DBS implantation. The presence of global differences provides an impetus for acquiring DWI shortly after implantation to establish a new baseline against which longitudinal changes in brain connectivity in DBS patients can be compared. Understanding that post-ope

This chapter explores the challenging question of curriculum and assessment for music improvisation pedagogy. It begins by offering a critical review of standard approaches to improvisation pedagogy, arguing that they often neglect the processes of discovery and collaboration that more open or “free” approaches afford. It then discusses the challenges that free improvisation poses to traditional modes of practice and assessment in music education. The chapter considers the argument that improvisation, in its fullest sense, cannot be taught and assessed according to standardized models; it is not something to be inculcated in students, but rather is a fundamental disposition that should be nurtured. This perspective is then developed in light of recent advances in enactive cognitive science, in which living cognition is explored as a fundamentally embodied, embedded, enactive, and extended (4E) phenomenon. The suggestion is made that because the ways living agents engage with these dimensions are not pre-given but rather reflect the adaptive processes associated with survival and well-being in contingent sociomaterial environments, there is a very strong sense in which cognition may be understood as an improvisational process even at the most fundamental levels. Following this, the chapter explores how a 4E cognition model might help guide curriculum development and offer a framework for forms of self-assessment involving collaborative processes of creative action and reflection. In conclusion, the chapter offers a few final thoughts drawn from existing musical communities and the author’s experience as an improvising musician.