title: Conditioned task-set competition: Neural mechanisms of emotional interference in depression.
abstract: Depression has been associated with increased response times at the incongruent-, neutral-, and negative-word trials of the classical and emotional Stroop tasks (Epp et al., Clinical Psychology Review, 32, 316-328, 2012). Response-time slowdown effects at incongruent- and negative-word trials of the Stroop tasks were reported to correlate with depressive severity, indicating strong relevance of the effects to the symptomatology. This study proposes a novel integrative computational model of neural mechanisms of both the classical and emotional Stroop effects, drawing on the previous prominent theoretical explanations of performance at the classical Stroop task (Cohen, Dunbar, & McClelland, Psychological Review, 97, 332-361, 1990; Herd, Banich, & O'Reilly, Journal of Cognitive Neuroscience, 18, 22-32, 2006), and in addition suggesting that negative emotional words represent conditioned stimuli for future negative outcomes. The model is shown to explain the classical Stroop effect and the slow (between-trial) emotional Stroop effect with biologically plausible mechanisms, providing an advantage over the previous theoretical accounts (Matthews & Harley, Cognition & Emotion, 10, 561-600, 1996; Wyble, Sharma, & Bowman, Cognition & Emotion, 22, 1019-1051, 2008). Simulation results suggested a candidate mechanism responsible for the pattern of depressive performance at the classical and the emotional Stroop tasks. Hyperactivity of the amygdala, together with increased inhibitory influence of the amygdala over dopaminergic neurotransmission, could be at the origin of the performance deficits.
authors.affiliation: Institute for Adaptive and Neural Computation, School of Informatics, University of Edinburgh, 10 Crichton Street, Edinburgh, EH8 9AB, UK.
authors.forename: Aleks
authors.initials: A
authors.lastname: Stolicyn
authors.affiliation: School of Medicine (Neuroscience), University of Dundee, Ninewells Hospital and Medical School, Dundee, DD1 9SY, UK.
authors.forename: J Douglas
authors.initials: JD
authors.lastname: Steele
authors.affiliation: Institute for Adaptive and Neural Computation, School of Informatics, University of Edinburgh, 10 Crichton Street, Edinburgh, EH8 9AB, UK. pseries@inf.ed.ac.uk.
authors.forename: Peggy
authors.initials: P
authors.lastname: Seriès
mesh_terms: D000679:Amygdala / Q000503:physiopathology*; D000818:Animals; D003198:Computer Simulation; D003213:Conditioning, Psychological / Q000502:physiology; D003866:Depressive Disorder / Q000503:physiopathology*; D004298:Dopamine / Q000378:metabolism; D004644:Emotions / Q000502:physiology*; D006801:Humans; D008959:Models, Neurological; D009434:Neural Pathways / Q000503:physiopathology; D017397:Prefrontal Cortex / Q000503:physiopathology; D011930:Reaction Time; D057190:Stroop Test; D017557:Ventral Tegmental Area / Q000503:physiopathology
chemical_list: D004298:Dopamine
keywords: Amygdala; Computational model; Depression; Dopamine; Emotion; Neural network