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Hartmut Heinrich - One of the best experts on this subject based on the ideXlab platform.
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differential effects of methylphenidate and atomoxetine on Attentional processes in children with adhd an event related potential study using the Attention Network Test
Progress in Neuro-psychopharmacology & Biological Psychiatry, 2012Co-Authors: Oliver Kratz, Petra Studer, Susanne Malcherek, Karlheinz Erbe, Gunther H Moll, Jeska Baack, Hartmut HeinrichAbstract:Abstract Methylphenidate (MPH) and atomoxetine (ATX) are effective medications in the treatment of Attention deficit/hyperactivity disorder (ADHD). The aim of this study was to investigate differential effects of MPH and ATX on Attentional functions at the performance and the neuronal level in children with ADHD. Using the Attention Network Test (ANT), differential effects of both medications on the noradrenergic alerting Network and the dopaminergic executive Attention Network were considered. Nineteen children with ADHD performed the ANT three times while event-related potentials (ERPs) were recorded. The baseline Testing was conducted without medication. In two medication blocks of 8 weeks each, medication was individually titrated for each child (cross-over design, balanced order). At the end of the medication blocks the Testing was repeated. While both medications comparably reduced ADHD symptomatology, MPH had some advantages over ATX with regard to performance measures on the ANT and the underlying neuronal mechanisms. Compared with ATX, MPH led to a larger reduction in reaction time variability, which was accompanied by an MPH-related increase in the contingent negative variation (CNV) compared to the baseline Testing. Contrary to our expectations, specific alerting Network effects were not observed with ATX. Due to the chosen study design, it remains unresolved to what extent e.g. shortened reaction times and smaller conflict scores that were observed with both medications reflect practice or medication effects. The differential pattern of MPH vs. ATX effects on Attentional functions in children with ADHD may be explained by the dopaminergic effects of MPH within the cortico-striato-thalamo-cortical circuit.
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Attentional processes in children with adhd an event related potential study using the Attention Network Test
International Journal of Psychophysiology, 2011Co-Authors: Oliver Kratz, Petra Studer, Susanne Malcherek, Karlheinz Erbe, Gunther H Moll, Hartmut HeinrichAbstract:A variety of event-related potential (ERP) based studies have shown differences in neuronal processes underlying Attention, inhibition and error processing in children with Attention-deficit/hyperactivity disorder (ADHD) compared to controls. However, so far there are no studies that have compared children with ADHD and typically developing (TD) children regarding effects in ERP components associated with the Attention Network Test (ANT). The ANT allows to differentiate between three particular aspects of Attention: alerting, orienting, conflict. Twenty-five children with ADHD and 19 TD children (comparable with respect to age, sex, and IQ) performed the ANT while ERPs were recorded. Based on DSM-IV, the group of children with ADHD was divided in an inattentive (ADHDin, n=10) and a combined (ADHDcom, n=15) subgroup. On the performance level, the ADHD group showed a significantly higher variability of reaction times. Concerning ERP measures, smaller cue-P3 amplitudes were found in the ADHD group indicating that children with ADHD allocate less Attentional resources for cue processing. In addition, the target-P3 in ADHD showed smaller amplitudes. Subgroup analysis revealed reduced cue-P3 amplitudes in both subgroups and reduced target-P3 amplitudes in ADHDin compared to TD children. Except for a higher alerting score in ADHD after correction for cue-P3 group differences, performance data revealed no group differences specific for the three Attention Networks. No group differences related to the Attention Networks were observed at the ERP level. Our results suggest that deviant Attentional processing in children with ADHD is only partly related to ANT-specific effects. Findings are compatible with the model of a suboptimal energetic state regulation in ADHD. Furthermore, our results suggest that deviant cue processing in ADHD and related differences in task modulations should be accounted for in data analysis.
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neurofeedback in children with adhd specific event related potential findings of a randomized controlled trial
Clinical Neurophysiology, 2011Co-Authors: Susanne Wangler, Petra Studer, Gunther H Moll, Holger Gevensleben, Bjorn Albrecht, Aribert Rothenberger, Hartmut HeinrichAbstract:Abstract Objective In a randomized controlled trial, we could demonstrate clinical efficacy of neurofeedback (NF) training for children with ADHD (Gevensleben et al., 2009a). The present investigation aimed at learning more about the neuronal mechanisms of NF training. Methods Children with ADHD either completed a NF training or a computerized Attention skills training (ratio 3:2). NF training consisted of one block of theta/beta training and one block of slow cortical potential (SCP) training, each comprising 18 training units. At three times (pre-training, between the two training blocks and at post-training), event-related potentials (ERP) were recorded during the Attention Network Test. ERP analysis focused on the P3, reflecting inter alia Attentional resources for stimulus evaluation, and the contingent negative variation (CNV), primarily related to cognitive preparation. Results After NF training, an increase of the CNV in cue trials could be observed, which was specific for the SCP training. A larger pre-training CNV was associated with a larger reduction of ADHD symptomatology for SCP training. Conclusions CNV effects reflect neuronal circuits underlying resource allocation during cognitive preparation. These distinct ERP effects are closely related to a successful NF training in children with ADHD. In future studies, neurophysiological recordings could help to optimize and individualize NF training. Significance The findings contribute to a better understanding of the mechanisms underlying NF training in children with ADHD.
Raymond M Klein - One of the best experts on this subject based on the ideXlab platform.
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comparing youth engagement on the Attentiontrip to the child Attention Network Test
International Journal of Human-computer Interaction, 2021Co-Authors: Swasti Arora, Colin R Mccormick, Raymond M KleinAbstract:Attentional abilities affect the social, cognitive, and intellectual growth of human development. Tools for the assessment of Attention can facilitate the early diagnosis of Attention disorders and...
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comparing bilingual and monolingual performance on the Attention Network Test meta analysis of a literature inspired by albert costa
Journal of Cultural Cognitive Science, 2020Co-Authors: Swasti Arora, Raymond M KleinAbstract:Are there differences between bilinguals and monolinguals in non-linguistic cognitive processes related to Attention? Recent interest in this question, which has a long history, was stimulated by ideas presented in Bialystok’s 2001 book: Bilingualism in development: Language, literacy, and cognition. Because Attention is a multi-faceted construct Costa et al. (Cognition 106(1):59–86, 2008, Cognition 113(2):135–149, 2009) sought to answer this question using the Attention Network Test (ANT), a simple-to-administer tool that was designed to measure the efficacy of three Attention Networks: alerting, orienting and executive control. Using the ANT Database, a recently developed repository of data extracted from studies that have used the ANT to answer any question, we identified 16 papers that followed Costa’s pioneering use of the ANT to address the question whether bilingualism is associated with differences in Attention. In this paper we begin by reviewing the methods and findings from Costa’s studies, and then report the results of three meta-analyses (conducted separately for children, young adults and middle-aged adults) of the data reported in these 16 papers. Whereas, there were no noteworthy effects of language status on alerting or orienting in any group, our meta-analysis of the studies that Tested young adults revealed, in agreement with Costa et al. (2008) a bilingual advantage in executive control. A similar bilingual advantage was not observed in the other age groups.
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Effects of fatigue on Attention and vigilance as measured with a modified Attention Network Test
Experimental Brain Research, 2020Co-Authors: Brett B. T. Feltmate, Austin J. Hurst, Raymond M KleinAbstract:As part of a larger study on the effects of fatigue on various Attentional and behavioural measures, we had participants complete a modified version of Luna et al.’s (J Neurosci Methods 306:77–87, Luna et al., J Neurosci Methods 306:77–87, 2018) ANTI-Vea task (mANTI-Vea) at the beginning and end (pre/post) of each of two 8-h Testing sessions. Between these administrations of the mANTI-Vea our participants spent ~ 6 h performing an intervening task. Our intent in this project was two-fold: first, to replicate the pattern of effects reported in Luna et al.’s original presentation of the ANTI-Vea; second, to assay the impact of fatigue on vigilance and Attention by observing shifts in mANTI-Vea performance as a function of time on task and before versus after the intervening task. With time-on-task (the mANTI-Vea is divided into six sub-blocks) we observed that participants became increasingly conservative in their biases to respond towards infrequent targets, showed a decline in sensitivity, and lapsed in responding in the psychomotor vigilance task with greater frequency. In the pre/post comparison, we observed an increase in the proportion of lapses, but not in participants’ response biases. Attentional Network scores were found to be somewhat insensitive to our fatigue manipulations; the effect of time-on-task was only significant for orienting scores on RT, and our pre/post comparison was only significant for RT derived executive functioning scores.
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the Attention Network Test database adhd and cross cultural applications
Frontiers in Psychology, 2020Co-Authors: Swasti Arora, Michael A Lawrence, Raymond M KleinAbstract:Attention is a central component of cognitive and behavioral processes and plays a key role in basic and higher-level functioning. Posner's model of Attention describes three components or Networks of Attention: the alerting, which involves high intensity states of arousal; the orienting, which involves the selective direction of Attention; and the executive control, which involves cognitive functions such as conflict resolution and working memory. The Attention Network Test (ANT) is a computerized Testing measure that was developed to measure these three Networks of Attention. This project describes the ANT, its widely used variants, and the recently developed ANT Database, a repository of data extracted from all studies that have used the ANT as of 2019. To illustrate the potential uses of the database, two meta-analyses conducted using the ANT Database are described. One explores task performance in children with and without Attention deficit/hyperactivity disorder (ADHD). The other one explores regional differences between studies conducted in China, Europe, and the United States. We are currently in the process of integrating the database into a publicly available web interface. When that work is complete, researchers, clinicians, and the general public will be able to use the database to explore topics of interest related to Attention.
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a comparison of engagement between the Attention Network Test and a videogame like version called the Attentiontrip
International Journal of Human-computer Interaction, 2019Co-Authors: Raymond M Klein, Emily Howes Vallis, Joseph D ChisholmAbstract:ABSTRACTThe concept of Attention is pivotal for our understanding of normal and abnormal human performance. The Attention Network Test (ANT) is a frequently used task for measuring three Networks o...
Michael Dettling - One of the best experts on this subject based on the ideXlab platform.
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Test reTest reliability of Attention Network Test measures in schizophrenia
Schizophrenia Research, 2011Co-Authors: Eric Hahn, Andres H Neuhaus, Constanze Hahn, Linn K Kuehl, Claudia Ruehl, Michael DettlingAbstract:Abstract Background The Attention Network Test (ANT) is a well established behavioral measure in neuropsychological research to assess three different facets of selective Attention, i.e., alerting, orienting, and conflict processing. Although the ANT has been applied in healthy individuals and various clinical populations, data on reTest reliability are scarce in healthy samples and lacking for clinical populations. The objective of the present study was a longitudinal assessment of relevant ANT Network measures in healthy controls and schizophrenic patients. Methods Forty-five schizophrenic patients and 55 healthy controls were Tested with ANT in a Test–reTest design with an average interval of 7.4 months between Test sessions. Test–reTest reliability was analyzed with Pearson and Intra-class correlations. Results Healthy controls revealed moderate to high Test–reTest correlations for mean reaction time, mean accuracy, conflict effect, and conflict error rates. In schizophrenic patients, moderate Test–reTest correlations for mean reaction time, orienting effect, and conflict effect were found. The analysis of error rates in schizophrenic patients revealed very low Test–reTest correlations. Conclusions The current study provides converging statistical evidence that the conflict effect and mean reaction time of ANT yield acceptable Test–reTest reliabilities in healthy controls and, investigated longitudinally for the first time, also in schizophrenia. Obtained differences of alerting and orienting effects in schizophrenia case–control studies should be considered more carefully. The analysis of error rates revealed heterogeneous results and therefore is not recommended for case control studies in schizophrenia.
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event related potentials associated with Attention Network Test
International Journal of Psychophysiology, 2010Co-Authors: Andres H Neuhaus, Carsten Urbanek, Eric Hahn, Carolin Opgenrhein, Simone Koehler, Melanie Gross, Michael DettlingAbstract:Selective visual Attention is thought to be comprised of distinct neuronal Networks that serve different Attentional functions. The Attention Network Test (ANT) has been introduced to allow for assessment of alerting, orienting, and response inhibition. Information on associated measures of neural processing during ANT is still scarce. We topographically analyzed top-down ANT effects on visual event-related potential morphology in 44 healthy participants. Significant reaction time effects were obtained for all Attention Networks. Posterior cue-locked target N1 amplitude was significantly increased during both alerting and orienting. P3 amplitude was significantly modulated at frontal and parietal leads as a function of inhibition. Our data suggests that Attentional mechanisms of alerting and orienting are employed simultaneously at early stages of the visual processing stream to amplify perceptual discrimination and load onto the same ERP component. Fronto-parietal modulations of P3 amplitude seem to mirror both response inhibition and visual target detection and may be interesting markers for further studies.
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Attention Network Test ant reveals gender specific alterations of executive function in schizophrenia
Psychiatry Research-neuroimaging, 2009Co-Authors: Carsten Urbanek, Eric Hahn, Carolin Opgenrhein, Andres Neuhaus, Silke Strathmann, Nicol Wieseke, Rainer Schaub, Michael DettlingAbstract:The Attention Network Test (ANT) provides measures for three different components of visual Attention: executive control (=conflict inhibition), orienting, and alerting. There is reasonable evidence that alterations of Attention-mainly in the executive/conflict domain-are associated with susceptibility to psychiatric illness. Specific impairments may be a characteristic for a medical condition such as schizophrenia and thus shift our understanding from a neuropsychological endophenotype to a more precise genetic understanding of this disorder. Study subjects comprised 35 schizophrenic patients and 35 healthy controls (13 female and 22 male in both groups). The ANT was administered to all participants and rated individual responses for the three factors (alerting, orienting, and conflict) and their respective ratios relative to mean reaction times. With regard to gender differences, group comparisons were performed for schizophrenic patients vs. healthy controls. Significant differences between patients and controls could be detected for mean reaction time (639 vs. 538 ms) and for conflict ratio (0.158 vs. 0.191). The latter difference mainly resulted from gender-specific variances of the conflict Network in opposite directions. The executive function as represented by the conflict Network of visual Attention of the ANT is affected in schizophrenia. We have detected hitherto unreported gender-specific differences between healthy controls and schizophrenic patients. Especially as regards the conflict Network, the ANT offers a promising methodology to detect a neuropsychological endophenotype of schizophrenia.
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executive Attention in schizophrenic males and the impact of comt val108 158met genotype on performance on the Attention Network Test
Schizophrenia Bulletin, 2008Co-Authors: Carolin Opgenrhein, Carsten Urbanek, Eric Hahn, Andres H Neuhaus, Thomas Sander, Michael DettlingAbstract:Background: Executive control of Attention in schizophrenia has recently been assessed by means of the Attention Network Test (ANT). In the past, for tasks assessing executive Attention, findings in schizophrenia have been contradictory, among others suggesting a lack of increased stimulus interference effects. Attention and executive functioning are substantially influenced by candidate genes of schizophrenia, including the functional single-nucleotide polymorphism catechol-o-methyltransferase (COMT) Val108/158Met, with task-dependent, specific effects of Met allele load on cognitive function. Therefore, we aimed at investigating executive Attention in schizophrenic patients (SZP) as compared with healthy controls (HC), and to assess the specific impact of COMT Val108/158Met on executive Attention, using ANT. Methods: We applied ANT to 63 SZP and 40 HC. We calculated a general linear model to investigate the influence of affection status and the COMT Val108/158Met genotype on executive Attention as assessed by the ANT. Results: Multivariate analysis of variance revealed a significant effect of group on executive Attention. SZP exhibited smaller conflict effects in the ANT. Met allele load significantly modulated executive Attention efficiency, with homozygous Met individuals showing low overall reaction time but increased effects conflicting stimulus information in executive Attention. Conclusions: Our data suggest a disease-related dissociation of executive Attention with reduced conflict effects in SZP. Furthermore, they support the hypothesis of differential tonic-phasic dopamine activation and specific dopamine level effects in different cognitive tasks, which helps interpreting contradictory findings of Met allele load on cognitive performance. Disease status seems to modulate the impact of COMT Val108/158Met on cognitive performance.
Maria Casagrande - One of the best experts on this subject based on the ideXlab platform.
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development in Attention functions and social processing evidence from the Attention Network Test
British Journal of Development Psychology, 2017Co-Authors: Francesca Federico, Andrea Marotta, Diana Martella, Maria CasagrandeAbstract:According to the Attention Network approach, Attention is best understood in terms of three functionally and neuroanatomically distinct Networks – alerting, orienting, and executive Attention. Recent findings showed that social information influences the efficiency of these Networks in adults. Using some social and non-social variants of the Attentional Network Test (ANT), this study was aimed to evaluate the development of the three Attention Networks in childhood, also assessing the development of the ability to manage social or non-social conflicting information. Sixty-six children (three groups of 6, 8, and 10 years of age) performed three variants of the original ANT, using fish, schematic, or real faces looking to the left or right as target and flanker stimuli. Results showed an improvement from 6 to 8 and 10 years of age in reaction time (RT) and accuracy, together with an improvement of executive control and a decrement in alerting. These developmental changes were not unique to social stimuli, and no differences were observed between social and no-social variants of the ANT. However, independently from the age of the children, a real face positively affected the executive control (as indexed by RTs) as compared to both a schematic face and a fish. Findings of this study suggest that Attentional Networks are still developing from 6 to 10 years of age and underline the importance of face information in modulating the efficiency of executive control. Statement of contribution What is already known? Younger children made more errors and slower reaction times (RTs) than older children, in line with the majority of the past selective Attention studies. Younger children showed both greater conflict and alerting effect than older children. The prediction that younger children would display larger interference effects than older children was supported. What does this study add? Extending the findings observed in adults and children, independently from their age, demonstrated greater cognitive interference (i.e., slower RTs and higher percentage of errors to incongruent relative to congruent conditions) when fish and schematic faces were presented than when photographs of real faces were used as stimuli. Like adults, children have a greater ability in the control of social information as compared to non-social information. These results seem to indicate that the ability to handle social conflicts proceeds in parallel with the ability to manage non-social conflicting information.
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Attention Network Test the impact of social information on executive control alerting and orienting
Acta Psychologica, 2013Co-Authors: Francesca Federico, Andrea Marotta, Tiziana Adriani, Lisa Maccari, Maria CasagrandeAbstract:Abstract According to the Attention Network approach, Attention is best understood in terms of three functionally and neuroanatomically distinct Networks — alerting, orienting, and executive Attention. An important question is whether social information influences the efficiency of these Networks. Using the same structure as the Attentional Network Test (ANT), we developed a variant of this Test to examine Attentional effects in response to stimuli with and without social-cognitive content. Fish, drawings or photographs of faces looking to the left or right were used as target stimuli. Results collected from twenty-four university students showed that photographs of faces positively affected Attentional orienting and executive control, whereas reduced the efficiency of alerting, as compared to both face drawings and fish. These results support the status of human faces as a special class of visual stimuli for the human Attentional systems.
Eric Hahn - One of the best experts on this subject based on the ideXlab platform.
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Test reTest reliability of Attention Network Test measures in schizophrenia
Schizophrenia Research, 2011Co-Authors: Eric Hahn, Andres H Neuhaus, Constanze Hahn, Linn K Kuehl, Claudia Ruehl, Michael DettlingAbstract:Abstract Background The Attention Network Test (ANT) is a well established behavioral measure in neuropsychological research to assess three different facets of selective Attention, i.e., alerting, orienting, and conflict processing. Although the ANT has been applied in healthy individuals and various clinical populations, data on reTest reliability are scarce in healthy samples and lacking for clinical populations. The objective of the present study was a longitudinal assessment of relevant ANT Network measures in healthy controls and schizophrenic patients. Methods Forty-five schizophrenic patients and 55 healthy controls were Tested with ANT in a Test–reTest design with an average interval of 7.4 months between Test sessions. Test–reTest reliability was analyzed with Pearson and Intra-class correlations. Results Healthy controls revealed moderate to high Test–reTest correlations for mean reaction time, mean accuracy, conflict effect, and conflict error rates. In schizophrenic patients, moderate Test–reTest correlations for mean reaction time, orienting effect, and conflict effect were found. The analysis of error rates in schizophrenic patients revealed very low Test–reTest correlations. Conclusions The current study provides converging statistical evidence that the conflict effect and mean reaction time of ANT yield acceptable Test–reTest reliabilities in healthy controls and, investigated longitudinally for the first time, also in schizophrenia. Obtained differences of alerting and orienting effects in schizophrenia case–control studies should be considered more carefully. The analysis of error rates revealed heterogeneous results and therefore is not recommended for case control studies in schizophrenia.
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event related potentials associated with Attention Network Test
International Journal of Psychophysiology, 2010Co-Authors: Andres H Neuhaus, Carsten Urbanek, Eric Hahn, Carolin Opgenrhein, Simone Koehler, Melanie Gross, Michael DettlingAbstract:Selective visual Attention is thought to be comprised of distinct neuronal Networks that serve different Attentional functions. The Attention Network Test (ANT) has been introduced to allow for assessment of alerting, orienting, and response inhibition. Information on associated measures of neural processing during ANT is still scarce. We topographically analyzed top-down ANT effects on visual event-related potential morphology in 44 healthy participants. Significant reaction time effects were obtained for all Attention Networks. Posterior cue-locked target N1 amplitude was significantly increased during both alerting and orienting. P3 amplitude was significantly modulated at frontal and parietal leads as a function of inhibition. Our data suggests that Attentional mechanisms of alerting and orienting are employed simultaneously at early stages of the visual processing stream to amplify perceptual discrimination and load onto the same ERP component. Fronto-parietal modulations of P3 amplitude seem to mirror both response inhibition and visual target detection and may be interesting markers for further studies.
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Attention Network Test reveals alerting Network dysfunction in multiple sclerosis
Multiple Sclerosis Journal, 2010Co-Authors: Carsten Urbanek, Nicholetta Weingesevers, Judith Bellmannstrobl, Markus Bock, Jan Dorr, Eric Hahn, Andres H Neuhaus, Carolin Opgenrhein, Katja Herges, Caspar F PfuellerAbstract:Attention is one of the cognitive domains typically affected in multiple sclerosis. The Attention Network Test was developed to measure the function of the three distinct Attentional Networks, alerting, orienting, and executive control. The Attention Network Test has been performed in various neuropsychiatric conditions, but not in multiple sclerosis. Our objective was to investigate functions of Attentional Networks in multiple sclerosis by means of the Attention Network Test. Patients with relapsing-remitting multiple sclerosis (n = 57) and healthy controls (n = 57) matched for age, sex, and education performed the Attention Network Test. Significant differences between patients and controls were detected in the alerting Network (p = 0.003), in contrast to the orienting (p = 0.696) and the conflict (p = 0.114) Network of visual Attention. Mean reaction time in the Attention Network Test was significantly longer in multiple sclerosis patients than in controls (p = 0.032), Multiple sclerosis patients benefited less from alerting cues for conflict resolution compared with healthy controls. The Attention Network Test revealed specific alterations of the Attention Network in multiple sclerosis patients which were not explained by an overall cognitive slowing.
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Attention Network Test ant reveals gender specific alterations of executive function in schizophrenia
Psychiatry Research-neuroimaging, 2009Co-Authors: Carsten Urbanek, Eric Hahn, Carolin Opgenrhein, Andres Neuhaus, Silke Strathmann, Nicol Wieseke, Rainer Schaub, Michael DettlingAbstract:The Attention Network Test (ANT) provides measures for three different components of visual Attention: executive control (=conflict inhibition), orienting, and alerting. There is reasonable evidence that alterations of Attention-mainly in the executive/conflict domain-are associated with susceptibility to psychiatric illness. Specific impairments may be a characteristic for a medical condition such as schizophrenia and thus shift our understanding from a neuropsychological endophenotype to a more precise genetic understanding of this disorder. Study subjects comprised 35 schizophrenic patients and 35 healthy controls (13 female and 22 male in both groups). The ANT was administered to all participants and rated individual responses for the three factors (alerting, orienting, and conflict) and their respective ratios relative to mean reaction times. With regard to gender differences, group comparisons were performed for schizophrenic patients vs. healthy controls. Significant differences between patients and controls could be detected for mean reaction time (639 vs. 538 ms) and for conflict ratio (0.158 vs. 0.191). The latter difference mainly resulted from gender-specific variances of the conflict Network in opposite directions. The executive function as represented by the conflict Network of visual Attention of the ANT is affected in schizophrenia. We have detected hitherto unreported gender-specific differences between healthy controls and schizophrenic patients. Especially as regards the conflict Network, the ANT offers a promising methodology to detect a neuropsychological endophenotype of schizophrenia.
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executive Attention in schizophrenic males and the impact of comt val108 158met genotype on performance on the Attention Network Test
Schizophrenia Bulletin, 2008Co-Authors: Carolin Opgenrhein, Carsten Urbanek, Eric Hahn, Andres H Neuhaus, Thomas Sander, Michael DettlingAbstract:Background: Executive control of Attention in schizophrenia has recently been assessed by means of the Attention Network Test (ANT). In the past, for tasks assessing executive Attention, findings in schizophrenia have been contradictory, among others suggesting a lack of increased stimulus interference effects. Attention and executive functioning are substantially influenced by candidate genes of schizophrenia, including the functional single-nucleotide polymorphism catechol-o-methyltransferase (COMT) Val108/158Met, with task-dependent, specific effects of Met allele load on cognitive function. Therefore, we aimed at investigating executive Attention in schizophrenic patients (SZP) as compared with healthy controls (HC), and to assess the specific impact of COMT Val108/158Met on executive Attention, using ANT. Methods: We applied ANT to 63 SZP and 40 HC. We calculated a general linear model to investigate the influence of affection status and the COMT Val108/158Met genotype on executive Attention as assessed by the ANT. Results: Multivariate analysis of variance revealed a significant effect of group on executive Attention. SZP exhibited smaller conflict effects in the ANT. Met allele load significantly modulated executive Attention efficiency, with homozygous Met individuals showing low overall reaction time but increased effects conflicting stimulus information in executive Attention. Conclusions: Our data suggest a disease-related dissociation of executive Attention with reduced conflict effects in SZP. Furthermore, they support the hypothesis of differential tonic-phasic dopamine activation and specific dopamine level effects in different cognitive tasks, which helps interpreting contradictory findings of Met allele load on cognitive performance. Disease status seems to modulate the impact of COMT Val108/158Met on cognitive performance.