2016/01/19 by Pedro A. Valdés-Hernández, Valdes-Hernandez, Pedro A., Jihye Bae +9
Computer Science · Neuroscience · #Biological Physics (physics.bio-ph) #Blind Source Separation Techniques #FOS: Biological sciences #FOS: Physical sciences #Functional Brain Connectivity Studies #Neural dynamics and brain function #Neurons and Cognition (q-bio.NC) #Neuroscience and Neural Engineering
paper · pdf · doi:10.48550/arxiv.1601.05113
openalex publication_date 2016/01/19 · openalex created_date 2022/10/04 · openalex updated_date 2026/07/28
The curtain of technical limitations impeding rat multichannel non-invasive\nelectroencephalography (EEG) has risen. Given the importance of this\npreclinical model, development and validation of EEG source imaging (ESI) is\nessential. We investigate the validity of well-known human ESI methodologies in\nrats which individual tissue geometries have been approximated by those\nextracted from an MRI template, leading also to imprecision in electrode\nlocalizations. With the half and fifth sensitivity volumes we determine both\nthe theoretical minimum electrode separation for non-redundant scalp EEG\nmeasurements and the electrode sensitivity resolution, which vary over the\nscalp because of the head geometry. According to our results, electrodes should\nbe at least ~3-3.5 mm apart for an optimal configuration. The sensitivity\nresolution is generally worse for electrodes at the boundaries of the scalp\nmeasured region, though, by analogy with human montages, concentrates the\nsensitivity enough to localize sources. Cram 'er-Rao lower bounds of source\nlocalization errors indicate it is theoretically possible to achieve ESI\naccuracy at the level of anatomical structures, such as the stimulus-specific\nsomatosensory areas, using the template. More validation for this approximation\nis provided through the comparison between the template and the individual lead\nfield matrices, for several rats. Finally, using well-accepted inverse methods,\nwe demonstrate that somatosensory ESI is not only expected but also allows\nexploring unknown phenomena related to global sensory integration. Inheriting\nthe advantages and pitfalls of human ESI, rat ESI will boost the understanding\nof brain pathophysiological mechanisms and the evaluation of ESI methodologies,\nnew pharmacological treatments and ESI-based biomarkers.\n