Simulation of the primary somatosensory neocortex (S1)

Stephanie R. Jones PhD is a researcher working at the
Martinos Center for Biomedical Imaging
Massachusetts General Hospital
Department of Radiology

"My research focuses on understanding brain neurodynamics by combining insights from human experimental measures (MEG/EEG and fMRI) and computational neural network modeling. This two-fold approach enables us to make a connection between microscopic cellular level neuronal events and macroscopic, non-invasively measured, brain activity. I am particularly interested in the neurodynamics of attention in the somatosenosory system. Some of my current questions of inquiry include: How does selective tactile attention affect brain activity measured in both the time and frequency domain? Does this activity correlate with perception? Are there specific cellular level neuronal events that regulate this activity? "

A 200+ cell model of the S1 somatosensory neocortex was constructed utilizing 3 cell types which are realisticaly simulated using up to 8 ion channels. A language was developed to connect these cells into a microcircuit. The MEG was calculated as a function of the net sum of current flow perpendicular to the apical dendritic longitudinal axis of the model Pyramidal cells.

This work was reported in
J Neurophysiol 102: 3554–3572, 2009 --
Quantitative Analysis and Biophysically Realistic Neural Modeling of the MEG Mu Rhythm:
Rhythmogenesis and Modulation of Sensory-Evoked Responses



Movie (Mpeg 10.7 MB) of dipole activity in a 10x10 cell 3D matrix
of 100 Layer V and 100 Layer II/III Pyramidal cells from 3 perspectives.
30 inhibitory cells are not shown. The simulated MEG (lower-right) closely
emulates the response to a finger-tap in Human subjects