title: Abnormal neural filtering of irrelevant visual information in depression.
abstract: The pathophysiology of major depressive disorder (MDD) includes both affective and cognitive dysfunctions. We aimed to clarify how regions regulating affective processing interact with those involved in attention, and how such interaction impacts perceptual processing within sensory cortices. Based on previous work showing that top-down influences from attention can determine the processing of external inputs within early sensory cortices, we tested with functional magnetic resonance imaging (fMRI) whether MDD alters attentional ("top-down") effects on the neural filtering of irrelevant, nonemotional visual stimuli. The present fMRI study was conducted in 14 nonmedicated patients with a first episode of unipolar MDD and 14 matched controls. During scanning, subjects performed two tasks imposing two different levels of attentional load at fixation (easy or difficult), while irrelevant colored stimuli were presented in the periphery. Analyses of fMRI data revealed that MDD patients show (1) an abnormal filtering of irrelevant information in visual cortex, (2) an altered functional connectivity between frontoparietal networks and visual cortices, and (3) a hyperactivity in subgenual cingulate/medial orbitofrontal cortex that was modulated by attentional load. These results demonstrate that biological abnormalities contribute to the cognitive deficits seen in major depression, and clarify how neural networks implicated in mood regulation influence executive control and perceptual processes. These findings not only improve our understanding of the pathophysiological mechanisms underlying cognitive dysfunctions in MDD, but also shed new light on the interaction between cognition and mood regulation.
authors.affiliation: Cyclotron Research Centre, University of Liège, 4000 Liège, Belgium.
authors.forename: Martin
authors.initials: M
authors.lastname: Desseilles
authors.forename: Evelyne
authors.initials: E
authors.lastname: Balteau
authors.forename: Virginie
authors.initials: V
authors.lastname: Sterpenich
authors.forename: Thien Thanh
authors.initials: TT
authors.lastname: Dang-Vu
authors.forename: Annabelle
authors.initials: A
authors.lastname: Darsaud
authors.forename: Gilles
authors.initials: G
authors.lastname: Vandewalle
authors.forename: Geneviève
authors.initials: G
authors.lastname: Albouy
authors.forename: Eric
authors.initials: E
authors.lastname: Salmon
authors.forename: Fréderic
authors.initials: F
authors.lastname: Peters
authors.forename: Christina
authors.initials: C
authors.lastname: Schmidt
authors.forename: Manuel
authors.initials: M
authors.lastname: Schabus
authors.forename: Stephen
authors.initials: S
authors.lastname: Gais
authors.forename: Christian
authors.initials: C
authors.lastname: Degueldre
authors.forename: Christophe
authors.initials: C
authors.lastname: Phillips
authors.forename: Andre
authors.initials: A
authors.lastname: Luxen
authors.forename: Marc
authors.initials: M
authors.lastname: Ansseau
authors.forename: Pierre
authors.initials: P
authors.lastname: Maquet
authors.forename: Sophie
authors.initials: S
authors.lastname: Schwartz
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D001931:Brain Mapping / Q000379:methods; D003865:Major Depressive Disorder / Q000503:physiopathology* / Q000523:psychology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation / Q000379:methods*; D011597:Psychomotor Performance / Q000502:physiology; D014793:Visual Cortex / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult