MEG source models distinguish energy-onset responses from between-note transition responses

Evidence

Subjects watched a silent movie, while their AEFs were recorded; they were instructed to direct their attention to the movie. Spatio-temporal source analyses (Scherg 1990 ) were performed offline using the BESA 5.2 software package (BESA Software GmbH). Separate source models with one equivalent dipole in each hemisphere were created to analyze the P50m (using unfiltered data) and the sustained field (SF) (using data lowpass filtered at 1 Hz). Then, a model with two dipoles per hemisphere was built to localize the N1m/P2m complex associated with energy onset at the start of each sequence, and to localize changes between adjacent notes within a given sequence (pooled notes 2–4). — Dijk, Pim van, Physiology, Psychoacoustics and…, 4709

Categorization

• QUESTION: The attention diversion to a silent movie is a notable design choice — how does diverted attention shape the melodic processing signal being measured?