TY - JOUR
T1 - Depression alters "top-down" visual attention
T2 - a dynamic causal modeling comparison between depressed and healthy subjects
AU - Desseilles, Martin
AU - Schwartz, Sophie
AU - Dang-Vu, Thien Thanh
AU - Sterpenich, Virginie
AU - Ansseau, Marc
AU - Maquet, Pierre
AU - Phillips, Christophe
N1 - Copyright © 2010 Elsevier Inc. All rights reserved.
PY - 2011/1/15
Y1 - 2011/1/15
N2 - Using functional magnetic resonance imaging (fMRI), we recently demonstrated that nonmedicated patients with a first episode of unipolar major depression (MDD) compared to matched controls exhibited an abnormal neural filtering of irrelevant visual information (Desseilles et al., 2009). During scanning, subjects performed a visual attention task imposing two different levels of attentional load at fixation (low or high), while task-irrelevant colored stimuli were presented in the periphery. In the present study, we focused on the visuo-attentional system and used "Dynamic Causal Modeling" (DCM) on the same dataset to assess how attention influences a network of three dynamically-interconnected brain regions (visual areas V1 and V4, and intraparietal sulcus (P), differentially in MDD patients and healthy controls. Bayesian model selection (BMS) and model space partitioning (MSP) were used to determine the best model in each population. The best model for the controls revealed that the increase of parietal activity by high attention load was selectively associated with a negative modulation of P on V4, consistent with high attention reducing the processing of irrelevant colored peripheral stimuli. The best model accounting for the data from the MDD patients showed that both low and high attention levels exerted modulatory effects on P. The present results document abnormal effective connectivity across visuo-attentional networks in MDD, which likely contributes to deficient attentional filtering of information.
AB - Using functional magnetic resonance imaging (fMRI), we recently demonstrated that nonmedicated patients with a first episode of unipolar major depression (MDD) compared to matched controls exhibited an abnormal neural filtering of irrelevant visual information (Desseilles et al., 2009). During scanning, subjects performed a visual attention task imposing two different levels of attentional load at fixation (low or high), while task-irrelevant colored stimuli were presented in the periphery. In the present study, we focused on the visuo-attentional system and used "Dynamic Causal Modeling" (DCM) on the same dataset to assess how attention influences a network of three dynamically-interconnected brain regions (visual areas V1 and V4, and intraparietal sulcus (P), differentially in MDD patients and healthy controls. Bayesian model selection (BMS) and model space partitioning (MSP) were used to determine the best model in each population. The best model for the controls revealed that the increase of parietal activity by high attention load was selectively associated with a negative modulation of P on V4, consistent with high attention reducing the processing of irrelevant colored peripheral stimuli. The best model accounting for the data from the MDD patients showed that both low and high attention levels exerted modulatory effects on P. The present results document abnormal effective connectivity across visuo-attentional networks in MDD, which likely contributes to deficient attentional filtering of information.
KW - Attention
KW - Brain
KW - Depressive Disorder, Major
KW - Humans
KW - Magnetic Resonance Imaging
KW - Models, Neurological
KW - Photic Stimulation
KW - Visual Perception
U2 - 10.1016/j.neuroimage.2010.08.061
DO - 10.1016/j.neuroimage.2010.08.061
M3 - Article
C2 - 20807578
SN - 1053-8119
VL - 54
SP - 1662
EP - 1668
JO - NeuroImage
JF - NeuroImage
IS - 2
ER -