Tracing Neural Circuits by Dynamically Simulating Whole-Brain Activity Patterns in the Human Connectome
Universitat Pompeu Fabra, Dept of Technology, Spain
Institució Catalana de Recerca i Estudis Avançats (ICREA), Spain
How does one unravel neural circuits from whole-brain connectivity data? To answer that we build a large-scale dynamic simulation of the human connectome in virtual reality, that reconstructs whole-brain activity in real-time. Using DTI structural connectivity data from  we built an interactive 3D visualization of the human connectome network in an immersive virtual reality environment (Fig. 1) using the Unity 3D gaming engine. Further, the virtual reality brain network in Unity is coupled to a real-time neuronal simulator, iqr . As we see, coupling structural connectivity data with detailed enough neuronal population dynamics is sufficient in predicting functional correlations and large-scale activity patterns. We model neuronal dynamics by a linear-threshold filter (as work in progress, we are currently implementing population dynamics from mean-field models ). Each population module is stochastic, having Gaussian noise. The user can stimulate any region or simultaneous regions of the network with external input currents. The simulation then reconstructs reverberating neural activity propagating throughout the network in real-time. As an explicit example, we stimulate the superior parietal areas and watch causal activity propagating in the parietal lobe, indicative of visuo-motor integration (Fig. 2). This is a first step to simulating and mapping large-scale brain activity in real-time.
As quantitative analysis methods and data-recording technology in neuroscience make improvements, it is becoming evident large-scale dynamics and whole-brain quantitative measures play an important role. For instance, oscillations across large brain regions are precursors to several cognitive functions. Moreover, the causal map in these interactions is crucial. Compared to functional correlations, large-scale temporal activity maps across directionally connected brain structures serve as a more powerful tools to unravel mechanisms of large-scale neural circuits. Our results show that stimulating brain areas triggers a sequence of causal activations in associated network loops that represent cognitively related functions.
The work is supported by the CEEDS project (258749 FP7-ICT-2009-5)
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Large scale modeling,
Whole Brain dynamics,
Neuroinformatics 2013, Stockholm, Sweden, 27 Aug - 29 Aug, 2013.
Large scale modeling
(2013). Tracing Neural Circuits by Dynamically Simulating Whole-Brain Activity Patterns in the Human Connectome.
08 Apr 2013;
11 Jul 2013.
Mr. Riccardo Zucca, Universitat Pompeu Fabra, Dept of Technology, Barcelona, Spain, email@example.com