Benoit Bediou | Université de Genève (original) (raw)
Papers by Benoit Bediou
Executive functions (EFs) involve critical top-down cognitive processes underpinning higher-order... more Executive functions (EFs) involve critical top-down cognitive processes underpinning higher-order cognitive abilities, which are fundamental for a variety of life outcomes. Their structure and development during middle childhood remain yet partially understood. This study explores the developmental trajectory of EFs, focusing on inhibition, working memory (WM), and cognitive flexibility, in a cross-sectional sample of 294 children aged 8-12 years. Using a comprehensive battery of nine cognitive tasks and advanced psychometric modeling, we examined age-related improvements and structural changes in EFs. Our findings reveal significant developmental progress across all EF components, with performance enhancements correlating with age. More notably, including both traditional correlated models and innovative bifactor analyses, the results indicate a shift from a less differentiated two-factor structure among younger children, where WM and cognitive flexibility are merged, to a distinct threefactor structure in older children, aligning with adult-like EFs characterization. This transition underscores a gradual differentiation of EFs, challenging the notion of an uniform EFs development and highlighting the nuanced nature of these processes. Additionally, bifactor modeling illuminated a common EFs factor alongside domain-specific abilities, offering novel insights into the underlying architecture of EFs during this critical developmental stage. These findings not only contribute to our understanding of EFs' developmental dynamics, but also hold implications for applied research focused on interventions targeting cognitive development in middle childhood.
Understanding the impact of video games on our health is of critical importance in today's world ... more Understanding the impact of video games on our health is of critical importance in today's world where gaming is a prevalent form of entertainment. In the present study, we sought to disentangle the relationship between time spent playing video games and Internet Gaming Disorder (IGD). We collected both self-reported and actual gameplay from Riot Games' League of Legends players across two independents samples. We also calculated two new metrics: the propensity of a player to come back quickly to play a new game after the conclusion of a previous game, and the sensitivity to the reward of winning of this come-backfast behavior. None of these variables related to IGD, a pattern that persisted whether players were below or above 30 hours of gaming per week, the APA-proposed cutoff above which disordered gaming is likely to occur. In contrast, cognitive abilities as measured by computerbased tasks, were seen to increase linearly with game playing up to 30 hours per week and then level off beyond that. Strikingly, the best predictors of IGD were mental health factors (e.g., anxiety and depression). Meanwhile, several personality factors appeared as protective. These findings, replicated across two independent samples suggest that policies and procedures aimed solely at limiting screen time may not be effective at reducing IGD prevalence or symptoms, and alternative considerations that include mental health factors must be considered to safeguard the health and well-being of individuals.
Biological Psychiatry, May 1, 2022
Schizophrenia Research, 2006
Auditory hallucinations have been associated with a disruption in monitoring one&... more Auditory hallucinations have been associated with a disruption in monitoring one's own speech suggesting an autonoetic agnosia in schizophrenia. This deficit can be measured by a source monitoring task. Low frequency transcranial magnetic stimulations (rTMS) applied to the left temporoparietal cortex can inhibit cortical areas involved both in autonoetic agnosia (which means 'the inability to identify self-generated mental events') and in auditory hallucinations (AH) phenomena. Although improvements in AH have been repeatedly reported following rTMS treatment, effects on autonoetic agnosia measured by source monitoring have never been investigated. We aimed to investigate the relation between improvements in AH and source monitoring performance after rTMS treatment. Twenty four right-handed refractory schizophrenic patients with hallucinations randomly received sham or active 10.0001-Hz rTMS to the left temporoparietal cortex and performed 2 source monitoring tasks requiring discrimination between silent- and overt-reading words before and after rTMS sessions. Compared to sham, active rTMS significantly improved AH. Source monitoring performances and the improvements tended to correlate, which would support a specific relation between autonoetic agnosia and auditory hallucinations.
Springer eBooks, Oct 21, 2020
![Research paper thumbnail of Reconhecimento emocional de faces e funcionamento psicossocial de pessoas com esquizofrenia = Facial emotion recognition and psychosocial functioning of schizophrenic patients [Poster]](https://attachments.academia-assets.com/107821232/thumbnails/1.jpg)
](Volume IX Nº3 Maio/Junho 2007 cerca de 2-3% dos gastos totais dos serviços de saúde e sociais. (K... more Volume IX Nº3 Maio/Junho 2007 cerca de 2-3% dos gastos totais dos serviços de saúde e sociais. (Knapp M, 1997) Os estudos comparativos de COI ("cost-ofilness") entre diferentes países sugerem que os custos hospitalares representam a porção mais significativa dos custos directos em saúde na esquizofrenia. (Goeree R, 2004). Objectivos: Estudar o peso relativo dos parâmetros de internamento e reinternamento de doentes com esquizofrenia entre 2004 e 2006 no Serviço de Matosinhos do Hospital de Magalhães Lemos. Material e Métodos: Os dados foram recolhidos utilizando a base de dados do Serviço de Matosinhos. Esta base de dados inclui dados administrativos, sóciodemográficos e clínicos, relativos a todos os doentes desta área internados no serviço no triénio 2004-2006. Os dados recolhidos foram tratados estatisticamente para obter parâmetros descritivos. Resultados: A esquizofrenia foi a patologia responsável pelo maior número de internamentos, correspondendo a 26% dos internamentos neste triénio. O número médio global de dias de internamento em 2006 foi de 15,6 dias, com uma demora média na esquizofrenia de 18,9 dias. Em 2006, aproximadamente um quinto dos internamentos por esquizofrenia foram compulsivos. Conclusões: Os parâmetros estudados relativos aos internamentos num serviço de psiquiatria de doentes agudos foram substancialmente maiores nos doentes com esquizofrenia, comparativamente com outras perturbações psiquiátricas. A redução do número e duração dos internamentos, com vista à diminuição dos custos directos com a esquizofrenia deve incluir o tratamento médico adequado e intervenções psicossociais que visam optimização do funcionamento global do indivíduo (Kilian R, 2003).
Biomedicines
Emotional processing deficits are key features in major depressive disorder (MDD). Neuroimaging s... more Emotional processing deficits are key features in major depressive disorder (MDD). Neuroimaging studies indicate that the dorsolateral prefrontal cortex (DLPFC) plays a pivotal role in both depressive symptoms and emotional processing. Recently, transcranial Direct Current Stimulations (tDCS) applied over the DLPFCs have held the promise to alleviate the symptoms in patients with MDD, but the effect on emotional processing in the patients is unclear. Here, we investigated the effect of a single session of tDCS over the DLPFCs on the emotional processing in patients with treatment-resistant MDD. In a randomized sham-controlled study, 35 patients received a single 30 min session of either active (2 mA, n = 18) or sham tDCS (n = 17). The anode was placed over the left and the cathode over the right DLPFC. Emotional processing accuracy was measured by a facial emotion recognition (FER) task. We observed an overall improvement in FER performance after the active tDCS, but not the sham tD...
SEE PROFILE All in-text references underlined in blue are linked to publications on ResearchGate,... more SEE PROFILE All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
Conclusões: Os parâmetros estudados relativos aos internamentos num serviço de psiquiatria de doe... more Conclusões: Os parâmetros estudados relativos aos internamentos num serviço de psiquiatria de doentes agudos foram substancialmente maiores nos doentes com esquizofrenia, comparativamente com outras perturbações psiquiátricas. A redução do ...
Cognitive, Affective, & Behavioral Neuroscience, Jan 20, 2023
Action video game players (AVGPs) outperform nonvideo game players (NVGPs) on a wide variety of a... more Action video game players (AVGPs) outperform nonvideo game players (NVGPs) on a wide variety of attentional tasks, mediating benefits to perceptual and cognitive decision processes. A key issue in the literature is the extent to which such benefits transfer beyond cognition. Using steady-state visual evoked potentials (SSVEP) as a neural measure of attentional resource allocation, we investigated whether the attentional benefit of AVGPs generalizes to the processing of rapidly presented facial emotions. AVGPs (n = 36) and NVGPs (n = 32) performed a novel, attention-demanding emotion discrimination task, requiring the identification of a target emotion in one of two laterally presented streams of emotional faces. The emotional faces flickered at either 2.0 Hz or 2.5 Hz. AVGPs outperformed NVGPs at detecting the target emotions regardless of the type of emotion. Correspondingly, attentional modulation of the SSVEP at parieto-occipital recording sites was larger in AVGPs compared with NVGPs. This difference appeared to be driven by a larger response to attended information, as opposed to a reduced response to irrelevant distractor information. Exploratory analyses confirmed that this novel paradigm elicited the expected pattern of event-related potentials associated with target detection and error processing. These components did not, however, differ between groups. Overall, the results indicate enhanced discrimination of facial emotions in AVGPs arising from enhanced attentional processing of emotional information. This presents evidence for the attentional advantage of AVGPs to extend beyond perceptual and cognitive processes.
Technology, Mind, and Behavior
The possibility that playing action video games is associated with enhancements in certain aspect... more The possibility that playing action video games is associated with enhancements in certain aspects of cognitive function has attracted significant interest from researchers in education, psychology, and neuroscience. Previous meta-analyses indicated an overall positive relationship between action video game play and cognitive skills. However, follow-up to this previous work is warranted, not only because the amount of data has grown significantly since previous meta-analyses were conducted, but also because previous work left several issues unresolved (e.g., certain meta-analytic procedures). We conducted a literature search using predefined keywords and inclusion criteria to identify studies that examined the relationship between action video game play and cognitive skills. Data from (a) 105 cross-sectional studies (221 effect sizes) and (b) 28 intervention studies with an active control group (91 effect sizes) were analyzed separately via meta-analytic models for dependent effect sizes with robust variance estimates for correlated and hierarchical effects (CHE) and small-sample corrections. Consistent with our hypotheses, action video game players outperformed nonvideo game players in the cross-sectional meta-analysis (large effect, g = 0.64, 95% CI [0.53, 0.74]). Action video game play was causally related to improvements in cognitive skills in the intervention meta-analysis (small effect, g = 0.30, 95% CI [0.11, 0.50]). Publication bias was detected in the cross-sectional data set, with sensitivity analysis showing high heterogeneous estimates of the average unbiased effect. Publication bias was not detected in the intervention data set, but sensitivity analyses also point to heterogeneity. No significant moderators were found for either data set; however, this may be limited by small sample sizes.
There have been mixed messages about the impact of video games on cognition. Two meta-analyses pu... more There have been mixed messages about the impact of video games on cognition. Two meta-analyses published back to back in Psychological Bulletin have led to apparently conflicting conclusions (Bediou et al., 2018; Sala et al., 2018). Here we revisit this debate through two new meta-analyses focusing on the relationship between action-shooter video games and cognitive abilities in cross-sectional and intervention studies. References: Bediou, B., Adams, D. M., Mayer, R. E., Tipton, E., Green, C. S., & Bavelier, D. (2018). Meta-analysis of action video game impact on perceptual, attentional, and cognitive skills. Psychological Bulletin, 144(1), 77–110. https://doi.org/10.1037/bul0000130; OSF link: https://osf.io/3gd8v/ Sala, G., Tatlidil, K. S., & Gobet, F. (2018). Video game training does not enhance cognitive ability: A comprehensive meta-analytic investigation. Psychological Bulletin, 144(2), 111–139. https://doi.org/10.1037/bul0000139
Effects of outcomes and random arbitration on emotions
Action video game players demonstrate higher levels of attentional control compared to non-video ... more Action video game players demonstrate higher levels of attentional control compared to non-video game players in cognitive tasks. Whether this benefit extends to the processing of emotions remains unknown. The present study adapts the design of Mishra et al., (2011) to evaluate whether enhanced attentional control in action video game players provides advantages for the processing of emotional faces. We aim to complete a previous study using a statistically justified sample size.
Journal of Clinical Medicine, 2022
Although transcranial Direct Current stimulation (tDCS) shows promise in the treatment of major d... more Although transcranial Direct Current stimulation (tDCS) shows promise in the treatment of major depressive episodes, the optimal parameters and population to target remain unclear. We investigated the clinical interest of a 10 session tDCS regimen in patients with mild to severe treatment-resistant depression, in a pilot double-blind, randomized sham-controlled trial. tDCS was delivered over 5 consecutive days (two 30 min sessions per day separated by at least 2 h, 2 mA). The anode and cathode were placed over the left and the right dorsolateral prefrontal cortex, respectively. One month after tDCS, we observed significantly fewer patients who achieved remission (MADRS10 < 10) in the sham group (0 out of 18 patients) than in the active group (5 out of 21 patients; p = 0.05). However, no significant difference was observed between the groups regarding the mean scores of severity changes throughout the study period. Bifrontal add-on tDCS delivered twice per day over 5 days, in comb...
Executive functions (EFs) involve critical top-down cognitive processes underpinning higher-order... more Executive functions (EFs) involve critical top-down cognitive processes underpinning higher-order cognitive abilities, which are fundamental for a variety of life outcomes. Their structure and development during middle childhood remain yet partially understood. This study explores the developmental trajectory of EFs, focusing on inhibition, working memory (WM), and cognitive flexibility, in a cross-sectional sample of 294 children aged 8-12 years. Using a comprehensive battery of nine cognitive tasks and advanced psychometric modeling, we examined age-related improvements and structural changes in EFs. Our findings reveal significant developmental progress across all EF components, with performance enhancements correlating with age. More notably, including both traditional correlated models and innovative bifactor analyses, the results indicate a shift from a less differentiated two-factor structure among younger children, where WM and cognitive flexibility are merged, to a distinct threefactor structure in older children, aligning with adult-like EFs characterization. This transition underscores a gradual differentiation of EFs, challenging the notion of an uniform EFs development and highlighting the nuanced nature of these processes. Additionally, bifactor modeling illuminated a common EFs factor alongside domain-specific abilities, offering novel insights into the underlying architecture of EFs during this critical developmental stage. These findings not only contribute to our understanding of EFs' developmental dynamics, but also hold implications for applied research focused on interventions targeting cognitive development in middle childhood.
Understanding the impact of video games on our health is of critical importance in today's world ... more Understanding the impact of video games on our health is of critical importance in today's world where gaming is a prevalent form of entertainment. In the present study, we sought to disentangle the relationship between time spent playing video games and Internet Gaming Disorder (IGD). We collected both self-reported and actual gameplay from Riot Games' League of Legends players across two independents samples. We also calculated two new metrics: the propensity of a player to come back quickly to play a new game after the conclusion of a previous game, and the sensitivity to the reward of winning of this come-backfast behavior. None of these variables related to IGD, a pattern that persisted whether players were below or above 30 hours of gaming per week, the APA-proposed cutoff above which disordered gaming is likely to occur. In contrast, cognitive abilities as measured by computerbased tasks, were seen to increase linearly with game playing up to 30 hours per week and then level off beyond that. Strikingly, the best predictors of IGD were mental health factors (e.g., anxiety and depression). Meanwhile, several personality factors appeared as protective. These findings, replicated across two independent samples suggest that policies and procedures aimed solely at limiting screen time may not be effective at reducing IGD prevalence or symptoms, and alternative considerations that include mental health factors must be considered to safeguard the health and well-being of individuals.
Biological Psychiatry, May 1, 2022
Schizophrenia Research, 2006
Auditory hallucinations have been associated with a disruption in monitoring one&amp;amp;... more Auditory hallucinations have been associated with a disruption in monitoring one&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s own speech suggesting an autonoetic agnosia in schizophrenia. This deficit can be measured by a source monitoring task. Low frequency transcranial magnetic stimulations (rTMS) applied to the left temporoparietal cortex can inhibit cortical areas involved both in autonoetic agnosia (which means &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;the inability to identify self-generated mental events&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;) and in auditory hallucinations (AH) phenomena. Although improvements in AH have been repeatedly reported following rTMS treatment, effects on autonoetic agnosia measured by source monitoring have never been investigated. We aimed to investigate the relation between improvements in AH and source monitoring performance after rTMS treatment. Twenty four right-handed refractory schizophrenic patients with hallucinations randomly received sham or active 10.0001-Hz rTMS to the left temporoparietal cortex and performed 2 source monitoring tasks requiring discrimination between silent- and overt-reading words before and after rTMS sessions. Compared to sham, active rTMS significantly improved AH. Source monitoring performances and the improvements tended to correlate, which would support a specific relation between autonoetic agnosia and auditory hallucinations.
Springer eBooks, Oct 21, 2020
Volume IX Nº3 Maio/Junho 2007 cerca de 2-3% dos gastos totais dos serviços de saúde e sociais. (K... more Volume IX Nº3 Maio/Junho 2007 cerca de 2-3% dos gastos totais dos serviços de saúde e sociais. (Knapp M, 1997) Os estudos comparativos de COI ("cost-ofilness") entre diferentes países sugerem que os custos hospitalares representam a porção mais significativa dos custos directos em saúde na esquizofrenia. (Goeree R, 2004). Objectivos: Estudar o peso relativo dos parâmetros de internamento e reinternamento de doentes com esquizofrenia entre 2004 e 2006 no Serviço de Matosinhos do Hospital de Magalhães Lemos. Material e Métodos: Os dados foram recolhidos utilizando a base de dados do Serviço de Matosinhos. Esta base de dados inclui dados administrativos, sóciodemográficos e clínicos, relativos a todos os doentes desta área internados no serviço no triénio 2004-2006. Os dados recolhidos foram tratados estatisticamente para obter parâmetros descritivos. Resultados: A esquizofrenia foi a patologia responsável pelo maior número de internamentos, correspondendo a 26% dos internamentos neste triénio. O número médio global de dias de internamento em 2006 foi de 15,6 dias, com uma demora média na esquizofrenia de 18,9 dias. Em 2006, aproximadamente um quinto dos internamentos por esquizofrenia foram compulsivos. Conclusões: Os parâmetros estudados relativos aos internamentos num serviço de psiquiatria de doentes agudos foram substancialmente maiores nos doentes com esquizofrenia, comparativamente com outras perturbações psiquiátricas. A redução do número e duração dos internamentos, com vista à diminuição dos custos directos com a esquizofrenia deve incluir o tratamento médico adequado e intervenções psicossociais que visam optimização do funcionamento global do indivíduo (Kilian R, 2003).
Biomedicines
Emotional processing deficits are key features in major depressive disorder (MDD). Neuroimaging s... more Emotional processing deficits are key features in major depressive disorder (MDD). Neuroimaging studies indicate that the dorsolateral prefrontal cortex (DLPFC) plays a pivotal role in both depressive symptoms and emotional processing. Recently, transcranial Direct Current Stimulations (tDCS) applied over the DLPFCs have held the promise to alleviate the symptoms in patients with MDD, but the effect on emotional processing in the patients is unclear. Here, we investigated the effect of a single session of tDCS over the DLPFCs on the emotional processing in patients with treatment-resistant MDD. In a randomized sham-controlled study, 35 patients received a single 30 min session of either active (2 mA, n = 18) or sham tDCS (n = 17). The anode was placed over the left and the cathode over the right DLPFC. Emotional processing accuracy was measured by a facial emotion recognition (FER) task. We observed an overall improvement in FER performance after the active tDCS, but not the sham tD...
SEE PROFILE All in-text references underlined in blue are linked to publications on ResearchGate,... more SEE PROFILE All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
Conclusões: Os parâmetros estudados relativos aos internamentos num serviço de psiquiatria de doe... more Conclusões: Os parâmetros estudados relativos aos internamentos num serviço de psiquiatria de doentes agudos foram substancialmente maiores nos doentes com esquizofrenia, comparativamente com outras perturbações psiquiátricas. A redução do ...
Cognitive, Affective, & Behavioral Neuroscience, Jan 20, 2023
Action video game players (AVGPs) outperform nonvideo game players (NVGPs) on a wide variety of a... more Action video game players (AVGPs) outperform nonvideo game players (NVGPs) on a wide variety of attentional tasks, mediating benefits to perceptual and cognitive decision processes. A key issue in the literature is the extent to which such benefits transfer beyond cognition. Using steady-state visual evoked potentials (SSVEP) as a neural measure of attentional resource allocation, we investigated whether the attentional benefit of AVGPs generalizes to the processing of rapidly presented facial emotions. AVGPs (n = 36) and NVGPs (n = 32) performed a novel, attention-demanding emotion discrimination task, requiring the identification of a target emotion in one of two laterally presented streams of emotional faces. The emotional faces flickered at either 2.0 Hz or 2.5 Hz. AVGPs outperformed NVGPs at detecting the target emotions regardless of the type of emotion. Correspondingly, attentional modulation of the SSVEP at parieto-occipital recording sites was larger in AVGPs compared with NVGPs. This difference appeared to be driven by a larger response to attended information, as opposed to a reduced response to irrelevant distractor information. Exploratory analyses confirmed that this novel paradigm elicited the expected pattern of event-related potentials associated with target detection and error processing. These components did not, however, differ between groups. Overall, the results indicate enhanced discrimination of facial emotions in AVGPs arising from enhanced attentional processing of emotional information. This presents evidence for the attentional advantage of AVGPs to extend beyond perceptual and cognitive processes.
Technology, Mind, and Behavior
The possibility that playing action video games is associated with enhancements in certain aspect... more The possibility that playing action video games is associated with enhancements in certain aspects of cognitive function has attracted significant interest from researchers in education, psychology, and neuroscience. Previous meta-analyses indicated an overall positive relationship between action video game play and cognitive skills. However, follow-up to this previous work is warranted, not only because the amount of data has grown significantly since previous meta-analyses were conducted, but also because previous work left several issues unresolved (e.g., certain meta-analytic procedures). We conducted a literature search using predefined keywords and inclusion criteria to identify studies that examined the relationship between action video game play and cognitive skills. Data from (a) 105 cross-sectional studies (221 effect sizes) and (b) 28 intervention studies with an active control group (91 effect sizes) were analyzed separately via meta-analytic models for dependent effect sizes with robust variance estimates for correlated and hierarchical effects (CHE) and small-sample corrections. Consistent with our hypotheses, action video game players outperformed nonvideo game players in the cross-sectional meta-analysis (large effect, g = 0.64, 95% CI [0.53, 0.74]). Action video game play was causally related to improvements in cognitive skills in the intervention meta-analysis (small effect, g = 0.30, 95% CI [0.11, 0.50]). Publication bias was detected in the cross-sectional data set, with sensitivity analysis showing high heterogeneous estimates of the average unbiased effect. Publication bias was not detected in the intervention data set, but sensitivity analyses also point to heterogeneity. No significant moderators were found for either data set; however, this may be limited by small sample sizes.
There have been mixed messages about the impact of video games on cognition. Two meta-analyses pu... more There have been mixed messages about the impact of video games on cognition. Two meta-analyses published back to back in Psychological Bulletin have led to apparently conflicting conclusions (Bediou et al., 2018; Sala et al., 2018). Here we revisit this debate through two new meta-analyses focusing on the relationship between action-shooter video games and cognitive abilities in cross-sectional and intervention studies. References: Bediou, B., Adams, D. M., Mayer, R. E., Tipton, E., Green, C. S., & Bavelier, D. (2018). Meta-analysis of action video game impact on perceptual, attentional, and cognitive skills. Psychological Bulletin, 144(1), 77–110. https://doi.org/10.1037/bul0000130; OSF link: https://osf.io/3gd8v/ Sala, G., Tatlidil, K. S., & Gobet, F. (2018). Video game training does not enhance cognitive ability: A comprehensive meta-analytic investigation. Psychological Bulletin, 144(2), 111–139. https://doi.org/10.1037/bul0000139
Effects of outcomes and random arbitration on emotions
Action video game players demonstrate higher levels of attentional control compared to non-video ... more Action video game players demonstrate higher levels of attentional control compared to non-video game players in cognitive tasks. Whether this benefit extends to the processing of emotions remains unknown. The present study adapts the design of Mishra et al., (2011) to evaluate whether enhanced attentional control in action video game players provides advantages for the processing of emotional faces. We aim to complete a previous study using a statistically justified sample size.
Journal of Clinical Medicine, 2022
Although transcranial Direct Current stimulation (tDCS) shows promise in the treatment of major d... more Although transcranial Direct Current stimulation (tDCS) shows promise in the treatment of major depressive episodes, the optimal parameters and population to target remain unclear. We investigated the clinical interest of a 10 session tDCS regimen in patients with mild to severe treatment-resistant depression, in a pilot double-blind, randomized sham-controlled trial. tDCS was delivered over 5 consecutive days (two 30 min sessions per day separated by at least 2 h, 2 mA). The anode and cathode were placed over the left and the right dorsolateral prefrontal cortex, respectively. One month after tDCS, we observed significantly fewer patients who achieved remission (MADRS10 < 10) in the sham group (0 out of 18 patients) than in the active group (5 out of 21 patients; p = 0.05). However, no significant difference was observed between the groups regarding the mean scores of severity changes throughout the study period. Bifrontal add-on tDCS delivered twice per day over 5 days, in comb...