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Stimulus-action inhibition binding is stronger in GTS patients than healthy controls and affects inhibitory control corroborating the concept suggesting that GTS might be a condition of altered perception-action integration (binding); i.e. a disorder of purposeful actions.

Summary Cognitive flexibility is essential to achieve higher level goals. Cognitive theories assume that the activation/deactivation of goals and task rules is central to understand cognitive flexibility. However, how this activation/deactivation dynamic is implemented on a neurophysiological level is unclear. Using EEG-based multivariate pattern analysis (MVPA) methods, we show that activation of relevant information occurs parallel in time at multiple levels in the neurophysiological signal containing aspects of stimulus-related processing, response selection, and motor response execution, and relates to different brain regions. The intensity with which task sets are activated and processed dynamically decreases and increases. The temporal stability of these activations could, however, hardly explain behavioral performance. Instead, task set deactivation processes associated with left orbitofrontal regions and inferior parietal regions selectively acting on motor response task sets are relevant. The study shows how propositions from cognitive theories stressing the importance task set activation/deactivation during cognitive flexibility are implemented on a neurophysiological level.

Gilles de la tourette Syndrome (GtS) is a developmental disorder. empirical studies and an emerging cognitive framework on GtS suggest that GtS is a disorder of abnormally strong 'perception-action binding'. Theoretical considerations imply that the effectiveness of long-established behavioral interventions might be related to a normalization of increased binding in GtS. this has not been tested yet. We examined the effect of a standardized Comprehensive Behavior Intervention for Tics (CBIT) in n = 21 adolescent GTS patients and N = 21 healthy controls on perception-action binding in an inhibitory control paradigm. Prior to CBIT, GTS patients showed compromised performance compared to controls, specifically when inhibitory control was triggered by uni-modal visual compared to bi-modal stimuli. After CBIT intervention, GTS patient's performance was at the same level as healthy controls. This is supported by a Bayesian data analysis. CBIT specifically affected inhibitory control in a condition where reconfigurations of perception-action bindings are necessary to perform inhibitory control. A power of 95% was evident for these effects. CBIT reduces increased 'binding' between perception and action in GTS and thereby increases the ability to perform response inhibition. The results are the first to provide insights as to why CBIT is effective by relating elements of this intervention to overarching cognitive theoretical frameworks on perception-action bindings.Gilles de la Tourette Syndrome (GTS) is a developmental disorder with multi-faceted neuropsychiatric symptoms, as onset and highest prevalence in childhood or adolescence and is characterized by multiple motor and vocal tics 1,2 . Traditionally, GTS has been considered as a movement disorder. This is not undisputed though given that most tics can, at least partially, be controlled, are associated with premonitory sensations and might reflect motor learning and habit formation 3 . On the basis of these findings, it has recently been suggested that a hallmark of GTS is an abnormally strong interrelation of perceptual processes and motor actions, particularly between premonitory sensation including preceding urges and tics, and that GTS might be conceptualized as a disorder in which purposeful actions play an important role 3 . Indeed, several studies have reported that GTS patients make better use of multi-or bi-modal sensory stimuli for response selection 4,5 . Moreover, findings from procedural learning also suggest that GTS patients establish connections between stimuli and the corresponding response faster and more strongly 6,7 . In line with this, GTS is associated with increased habit formation tendencies 8 depending on the establishment of strong stimulus-response mappings. These findings corroborate the notion that GTS might be a disorder characterized by an abnormally strong 'binding' between perception and action, for which a cognitive framework based on the Theory of Event Coding (TEC) detailing the link between perception and action is an attractive o...

Demanding tasks like cognitive flexibility show time-related deterioration of performance (i.e. fatigability effects). Fatigability has been associated with structural and functional properties of the prefrontal cortex. However, the electrophysiological underpinnings of these processes are not well understood. We examined n = 34 healthy participants with a task switching paradigm in which switches were either signaled by cues or needed to be maintained by working memory processes. We analyzed event-related potentials (ERPs) and performed residue iteration decomposition (RIDE) to account for effects of fatigue on intra-individual variability of neurophysiological data. This was combined with source localization methods. We show that task switching is affected by time on task (TOT) effects mostly when working memory processes are needed. On a neurophysiological level, this effect could not be observed in standard ERPs, but only after accounting for intra-individual variability using RIDE. The RIDE data suggests that during task switching, fatigability specifically affects response recoding processes that are associated with functions of the middle frontal gyrus (MFG; BA10). The results underline propositions of the ‘opportunity cost model’, which states that fatigability effects of executive functions depend on the degree to which tasks engage similar prefrontal regions - in this case working memory and task switching mechanisms.