Stochastic dynamic causal modelling of fMRI data: should we care about neural noise?
Neuroimage
; 62(1): 464-81, 2012 Aug 01.
Article
in En
| MEDLINE
| ID: mdl-22579726
ABSTRACT
Dynamic causal modelling (DCM) was introduced to study the effective connectivity among brain regions using neuroimaging data. Until recently, DCM relied on deterministic models of distributed neuronal responses to external perturbation (e.g., sensory stimulation or task demands). However, accounting for stochastic fluctuations in neuronal activity and their interaction with task-specific processes may be of particular importance for studying state-dependent interactions. Furthermore, allowing for random neuronal fluctuations may render DCM more robust to model misspecification and finesse problems with network identification. In this article, we examine stochastic dynamic causal models (sDCM) in relation to their deterministic counterparts (dDCM) and highlight questions that can only be addressed with sDCM. We also compare the network identification performance of deterministic and stochastic DCM, using Monte Carlo simulations and an empirical case study of absence epilepsy. For example, our results demonstrate that stochastic DCM can exploit the modelling of neural noise to discriminate between direct and mediated connections. We conclude with a discussion of the added value and limitations of sDCM, in relation to its deterministic homologue.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Brain Mapping
/
Magnetic Resonance Imaging
/
Image Interpretation, Computer-Assisted
/
Stochastic Processes
/
Models, Statistical
/
Models, Neurological
/
Nerve Net
Type of study:
Diagnostic_studies
/
Prognostic_studies
/
Risk_factors_studies
Limits:
Humans
Language:
En
Journal:
Neuroimage
Journal subject:
DIAGNOSTICO POR IMAGEM
Year:
2012
Document type:
Article
Affiliation country: