Modulation of human corticospinal excitability by paired associative stimulation

Paired Associative Stimulation (PAS) has come to prominence as a potential therapeutic intervention for the treatment of brain injury/disease, and as an experimental method with which to investigate Hebbian principles of neural plasticity in humans. Prototypically, a single electrical stimulus is directed to a peripheral nerve in advance of transcranial magnetic stimulation (TMS) delivered to the contralateral primary motor cortex (M1). Repeated pairing of the stimuli (i.e., association) over an extended period may increase or decrease the excitability of corticospinal projections from M1, in manner that depends on the interstimulus interval (ISI). It has been suggested that these effects represent a form of associative long-term potentiation (LTP) and depression (LTD) that bears resemblance to spike-timing dependent plasticity (STDP) as it has been elaborated in animal models. With a large body of empirical evidence having emerged since the cardinal features of PAS were first described, and in light of the variations from the original protocols that have been implemented, it is opportune to consider whether the phenomenology of PAS remains consistent with the characteristic features that were initially disclosed. This assessment necessarily has bearing upon interpretation of the effects of PAS in relation to the specific cellular pathways that are putatively engaged, including those that adhere to the rules of STDP. The balance of evidence suggests that the mechanisms that contribute to the LTP- and LTD-type responses to PAS differ depending on the precise nature of the induction protocol that is used. In addition to emphasizing the requirement for additional explanatory models, in the present analysis we highlight the key features of the PAS phenomenology that require interpretation.

Ubiquitous Translation

In this book, Piotr Blumczynski explores the central role of translation as a key epistemological concept as well as a hermeneutic, ethical, linguistic and interpersonal practice. His argument is three-fold: (1) that translation provides a basis for genuine, exciting, serious, innovative and meaningful exchange between various areas of the humanities through both a concept (the WHAT) and a method (the HOW); (2) that, in doing so, it questions and challenges many of the traditional boundaries and offers a transdisciplinary epistemological paradigm, leading to a new understanding of quality, and thus also meaning, truth, and knowledge; and (3) that translational phenomena are studied by a broad range of disciplines in the humanities (including philosophy, theology, linguistics, and anthropology) using various, often seemingly unrelated concepts which nevertheless display a considerable degree of qualitative proximity. The common thread running through all these convictions and binding them together is the insistence that translational phenomena are ubiquitous. Because of its unconventional and innovative approach, this book will be of interest to translation studies scholars looking to situate their research within a broader transdisciplinary model, as well as to students of translation programs and practicing translators who seek a fuller understanding of why and how translation matters.

Equilibration and nonclassicality of a double-well potential

A double-well loaded with bosonic atoms represents an ideal candidate to simulate some of the most interesting aspects in the phenomenology of thermalisation and equilibration. Here we report an exhaustive analysis of the dynamics and steady state properties of such a system locally in contact with different temperature reservoirs. We show that thermalisation only occurs 'accidentally'. We further examine the nonclassical features and energy fluxes implied by the dynamics of the double-well system, thus exploring its finite-time thermodynamics in relation to the settlement of nonclassical correlations between the wells.