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Gesa Hartwigsen - One of the best experts on this subject based on the ideXlab platform.
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after effects of 10 hz tacs over the prefrontal cortex on Phonological Word decisions
Brain Stimulation, 2019Co-Authors: V Moliadze, Leon Sierau, Ekaterina Lyzhko, T Stenner, Michael Werchowski, Michael Siniatchkin, Gesa HartwigsenAbstract:Abstract Introduction Previous work in the language domain has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (pIFG) in the prefrontal cortex impaired Phonological decision-making, arguing for a causal contribution of the bilateral pIFG to Phonological processing. However, the neurophysiological correlates of these effects are unclear. The present study addressed the question whether neural activity in the prefrontal cortex could be modulated by 10 Hz tACS and how this would affect Phonological decisions. Methods In three sessions, 24 healthy participants received tACS at 10 Hz or 16.18 Hz (control frequency) or sham stimulation over the bilateral prefrontal cortex before task processing. Resting state EEG was recorded before and after tACS. We also recorded EEG during task processing. Results Relative to sham stimulation, 10 Hz tACS significantly facilitated Phonological response speed. This effect was task-specific as tACS did not affect a simple control task. Moreover, 10 Hz tACS significantly increased theta power during Phonological decisions. The individual increase in theta power was positively correlated with the behavioral facilitation after 10 Hz tACS. Conclusion Our results show a facilitation of Phonological decisions after 10 Hz tACS over the bilateral prefrontal cortex. This might indicate that 10 Hz tACS increased task-related activity in the stimulated area to a level that was optimal for Phonological performance. The significant correlation with the individual increase in theta power suggests that the behavioral facilitation might be related to increased theta power during language processing.
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p108 effects of 10 hz tacs on Phonological language processing
Clinical Neurophysiology, 2018Co-Authors: T Stenner, Gesa Hartwigsen, Leon Sierau, Michael Werchowski, Michael Siniatchkin, S Matern, Christian Kaernbach, V MoliadzeAbstract:Introduction A previous study ( Hartwigsen et al., 2010 ) has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (IFG) impaired performance in a Phonological decision-making task. However, it is unclear whether the neurodisruptive effect of 10 Hz-rTMS is caused by entrainment of alpha-oscillations. To address this issue, the present study investigated the following questions: (1) Are alpha-oscillations in the IFG functionally relevant for Phonological processing? (2) Can we enhance alpha activity in the IFG using 10 Hz tACS? and (3) Does enhancement of alpha activity cause behavioral disruption? Methods 24 right-handed, healthy participants (12 male, age range: 18–30 years, mean = 21.96, SD = 3.36) participated in the study. 9 mm2 circular sponge electrodes were placed over the bilateral IFG. In three separate sessions, 1 mA tACS at 10 Hz or 16.18 Hz or sham stimulation were applied for 20 min. Before and after stimulation, 5 min of resting state EEG was recorded. The Phonological task required the subjects to indicate via button press whether highly frequent German nouns like ‘Zebra’ consisted of two or three syllables. In a simple control task, participants had to indicate whether an arrow pointed left or right to control for unspecific effects. Results (1) Stimulation was a significant predictor for decision speed in the Phonological task (p = .02). Specifically, participants responded faster after 10 Hz relative to sham stimulation, but not after 16.18 Hz. (2) This effect was task specific as tACS did not significantly affect the control task (p = 0.43). (3) Participants had an increase in resting state alpha power (p = .004), which wasn’t modulated by stimulation (p = .70). (4) We found a significant event related desynchronization in the alpha band (p Conclusion The results show an improvement in a Phonological Word task after applying 10 Hz tACS over the bilateral IFG but not in simple motoric control task. This might be explained by a paradoxical facilitation effect, resulting in an ‘optimal’ level of noise for task processing ( Miniussi et al., 2013 ) or by inhibition of surrounding areas that might be competing for task resources. Since no specific effect on alpha oscillations could be found, further studies will therefore investigate effects of focal online stimulation.
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the right posterior inferior frontal gyrus contributes to Phonological Word decisions in the healthy brain evidence from dual site tms
Neuropsychologia, 2010Co-Authors: Gesa Hartwigsen, Cathy J. Price, Annette Baumgaertner, Gesine Geiss, Maria Koehnke, Stephan Ulmer, Hartwig R SiebnerAbstract:There is consensus that the left hemisphere plays a dominant role in language processing, but functional imaging studies have shown that the right as well as the left posterior inferior frontal gyri (pIFG) are activated when healthy right-handed individuals make Phonological Word decisions. Here we used online transcranial magnetic stimulation (TMS) to examine the functional relevance of the right pIFG for auditory and visual Phonological decisions. Healthy right-handed individuals made Phonological or semantic Word judgements on the same set of auditorily and visually presented Words while they received stereotactically guided TMS over the left, right or bilateral pIFG (n = 14) or the anterior left, right or bilateral IFG (n = 14). TMS started 100 ms after Word onset and consisted of four stimuli given at a rate of 10 Hz and intensity of 90% of active motor threshold. Compared to TMS of aIFG, TMS of pIFG impaired reaction times and accuracy of Phonological but not semantic decisions for visually and auditorily presented Words. TMS over left, right or bilateral pIFG disrupted Phonological processing to a similar degree. In a follow-up experiment, the intensity threshold for delaying Phonological judgements was identical for unilateral TMS of left and right pIFG. These findings indicate that an intact function of right pIFG is necessary for accurate and efficient Phonological decisions in the healthy brain with no evidence that the left and right pIFG can compensate for one another during online TMS. Our findings motivate detailed studies of Phonological processing in patients with acute and chronic damage of the right pIFG.
V Moliadze - One of the best experts on this subject based on the ideXlab platform.
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after effects of 10 hz tacs over the prefrontal cortex on Phonological Word decisions
Brain Stimulation, 2019Co-Authors: V Moliadze, Leon Sierau, Ekaterina Lyzhko, T Stenner, Michael Werchowski, Michael Siniatchkin, Gesa HartwigsenAbstract:Abstract Introduction Previous work in the language domain has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (pIFG) in the prefrontal cortex impaired Phonological decision-making, arguing for a causal contribution of the bilateral pIFG to Phonological processing. However, the neurophysiological correlates of these effects are unclear. The present study addressed the question whether neural activity in the prefrontal cortex could be modulated by 10 Hz tACS and how this would affect Phonological decisions. Methods In three sessions, 24 healthy participants received tACS at 10 Hz or 16.18 Hz (control frequency) or sham stimulation over the bilateral prefrontal cortex before task processing. Resting state EEG was recorded before and after tACS. We also recorded EEG during task processing. Results Relative to sham stimulation, 10 Hz tACS significantly facilitated Phonological response speed. This effect was task-specific as tACS did not affect a simple control task. Moreover, 10 Hz tACS significantly increased theta power during Phonological decisions. The individual increase in theta power was positively correlated with the behavioral facilitation after 10 Hz tACS. Conclusion Our results show a facilitation of Phonological decisions after 10 Hz tACS over the bilateral prefrontal cortex. This might indicate that 10 Hz tACS increased task-related activity in the stimulated area to a level that was optimal for Phonological performance. The significant correlation with the individual increase in theta power suggests that the behavioral facilitation might be related to increased theta power during language processing.
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p108 effects of 10 hz tacs on Phonological language processing
Clinical Neurophysiology, 2018Co-Authors: T Stenner, Gesa Hartwigsen, Leon Sierau, Michael Werchowski, Michael Siniatchkin, S Matern, Christian Kaernbach, V MoliadzeAbstract:Introduction A previous study ( Hartwigsen et al., 2010 ) has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (IFG) impaired performance in a Phonological decision-making task. However, it is unclear whether the neurodisruptive effect of 10 Hz-rTMS is caused by entrainment of alpha-oscillations. To address this issue, the present study investigated the following questions: (1) Are alpha-oscillations in the IFG functionally relevant for Phonological processing? (2) Can we enhance alpha activity in the IFG using 10 Hz tACS? and (3) Does enhancement of alpha activity cause behavioral disruption? Methods 24 right-handed, healthy participants (12 male, age range: 18–30 years, mean = 21.96, SD = 3.36) participated in the study. 9 mm2 circular sponge electrodes were placed over the bilateral IFG. In three separate sessions, 1 mA tACS at 10 Hz or 16.18 Hz or sham stimulation were applied for 20 min. Before and after stimulation, 5 min of resting state EEG was recorded. The Phonological task required the subjects to indicate via button press whether highly frequent German nouns like ‘Zebra’ consisted of two or three syllables. In a simple control task, participants had to indicate whether an arrow pointed left or right to control for unspecific effects. Results (1) Stimulation was a significant predictor for decision speed in the Phonological task (p = .02). Specifically, participants responded faster after 10 Hz relative to sham stimulation, but not after 16.18 Hz. (2) This effect was task specific as tACS did not significantly affect the control task (p = 0.43). (3) Participants had an increase in resting state alpha power (p = .004), which wasn’t modulated by stimulation (p = .70). (4) We found a significant event related desynchronization in the alpha band (p Conclusion The results show an improvement in a Phonological Word task after applying 10 Hz tACS over the bilateral IFG but not in simple motoric control task. This might be explained by a paradoxical facilitation effect, resulting in an ‘optimal’ level of noise for task processing ( Miniussi et al., 2013 ) or by inhibition of surrounding areas that might be competing for task resources. Since no specific effect on alpha oscillations could be found, further studies will therefore investigate effects of focal online stimulation.
T Stenner - One of the best experts on this subject based on the ideXlab platform.
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after effects of 10 hz tacs over the prefrontal cortex on Phonological Word decisions
Brain Stimulation, 2019Co-Authors: V Moliadze, Leon Sierau, Ekaterina Lyzhko, T Stenner, Michael Werchowski, Michael Siniatchkin, Gesa HartwigsenAbstract:Abstract Introduction Previous work in the language domain has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (pIFG) in the prefrontal cortex impaired Phonological decision-making, arguing for a causal contribution of the bilateral pIFG to Phonological processing. However, the neurophysiological correlates of these effects are unclear. The present study addressed the question whether neural activity in the prefrontal cortex could be modulated by 10 Hz tACS and how this would affect Phonological decisions. Methods In three sessions, 24 healthy participants received tACS at 10 Hz or 16.18 Hz (control frequency) or sham stimulation over the bilateral prefrontal cortex before task processing. Resting state EEG was recorded before and after tACS. We also recorded EEG during task processing. Results Relative to sham stimulation, 10 Hz tACS significantly facilitated Phonological response speed. This effect was task-specific as tACS did not affect a simple control task. Moreover, 10 Hz tACS significantly increased theta power during Phonological decisions. The individual increase in theta power was positively correlated with the behavioral facilitation after 10 Hz tACS. Conclusion Our results show a facilitation of Phonological decisions after 10 Hz tACS over the bilateral prefrontal cortex. This might indicate that 10 Hz tACS increased task-related activity in the stimulated area to a level that was optimal for Phonological performance. The significant correlation with the individual increase in theta power suggests that the behavioral facilitation might be related to increased theta power during language processing.
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p108 effects of 10 hz tacs on Phonological language processing
Clinical Neurophysiology, 2018Co-Authors: T Stenner, Gesa Hartwigsen, Leon Sierau, Michael Werchowski, Michael Siniatchkin, S Matern, Christian Kaernbach, V MoliadzeAbstract:Introduction A previous study ( Hartwigsen et al., 2010 ) has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (IFG) impaired performance in a Phonological decision-making task. However, it is unclear whether the neurodisruptive effect of 10 Hz-rTMS is caused by entrainment of alpha-oscillations. To address this issue, the present study investigated the following questions: (1) Are alpha-oscillations in the IFG functionally relevant for Phonological processing? (2) Can we enhance alpha activity in the IFG using 10 Hz tACS? and (3) Does enhancement of alpha activity cause behavioral disruption? Methods 24 right-handed, healthy participants (12 male, age range: 18–30 years, mean = 21.96, SD = 3.36) participated in the study. 9 mm2 circular sponge electrodes were placed over the bilateral IFG. In three separate sessions, 1 mA tACS at 10 Hz or 16.18 Hz or sham stimulation were applied for 20 min. Before and after stimulation, 5 min of resting state EEG was recorded. The Phonological task required the subjects to indicate via button press whether highly frequent German nouns like ‘Zebra’ consisted of two or three syllables. In a simple control task, participants had to indicate whether an arrow pointed left or right to control for unspecific effects. Results (1) Stimulation was a significant predictor for decision speed in the Phonological task (p = .02). Specifically, participants responded faster after 10 Hz relative to sham stimulation, but not after 16.18 Hz. (2) This effect was task specific as tACS did not significantly affect the control task (p = 0.43). (3) Participants had an increase in resting state alpha power (p = .004), which wasn’t modulated by stimulation (p = .70). (4) We found a significant event related desynchronization in the alpha band (p Conclusion The results show an improvement in a Phonological Word task after applying 10 Hz tACS over the bilateral IFG but not in simple motoric control task. This might be explained by a paradoxical facilitation effect, resulting in an ‘optimal’ level of noise for task processing ( Miniussi et al., 2013 ) or by inhibition of surrounding areas that might be competing for task resources. Since no specific effect on alpha oscillations could be found, further studies will therefore investigate effects of focal online stimulation.
Michael Siniatchkin - One of the best experts on this subject based on the ideXlab platform.
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after effects of 10 hz tacs over the prefrontal cortex on Phonological Word decisions
Brain Stimulation, 2019Co-Authors: V Moliadze, Leon Sierau, Ekaterina Lyzhko, T Stenner, Michael Werchowski, Michael Siniatchkin, Gesa HartwigsenAbstract:Abstract Introduction Previous work in the language domain has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (pIFG) in the prefrontal cortex impaired Phonological decision-making, arguing for a causal contribution of the bilateral pIFG to Phonological processing. However, the neurophysiological correlates of these effects are unclear. The present study addressed the question whether neural activity in the prefrontal cortex could be modulated by 10 Hz tACS and how this would affect Phonological decisions. Methods In three sessions, 24 healthy participants received tACS at 10 Hz or 16.18 Hz (control frequency) or sham stimulation over the bilateral prefrontal cortex before task processing. Resting state EEG was recorded before and after tACS. We also recorded EEG during task processing. Results Relative to sham stimulation, 10 Hz tACS significantly facilitated Phonological response speed. This effect was task-specific as tACS did not affect a simple control task. Moreover, 10 Hz tACS significantly increased theta power during Phonological decisions. The individual increase in theta power was positively correlated with the behavioral facilitation after 10 Hz tACS. Conclusion Our results show a facilitation of Phonological decisions after 10 Hz tACS over the bilateral prefrontal cortex. This might indicate that 10 Hz tACS increased task-related activity in the stimulated area to a level that was optimal for Phonological performance. The significant correlation with the individual increase in theta power suggests that the behavioral facilitation might be related to increased theta power during language processing.
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p108 effects of 10 hz tacs on Phonological language processing
Clinical Neurophysiology, 2018Co-Authors: T Stenner, Gesa Hartwigsen, Leon Sierau, Michael Werchowski, Michael Siniatchkin, S Matern, Christian Kaernbach, V MoliadzeAbstract:Introduction A previous study ( Hartwigsen et al., 2010 ) has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (IFG) impaired performance in a Phonological decision-making task. However, it is unclear whether the neurodisruptive effect of 10 Hz-rTMS is caused by entrainment of alpha-oscillations. To address this issue, the present study investigated the following questions: (1) Are alpha-oscillations in the IFG functionally relevant for Phonological processing? (2) Can we enhance alpha activity in the IFG using 10 Hz tACS? and (3) Does enhancement of alpha activity cause behavioral disruption? Methods 24 right-handed, healthy participants (12 male, age range: 18–30 years, mean = 21.96, SD = 3.36) participated in the study. 9 mm2 circular sponge electrodes were placed over the bilateral IFG. In three separate sessions, 1 mA tACS at 10 Hz or 16.18 Hz or sham stimulation were applied for 20 min. Before and after stimulation, 5 min of resting state EEG was recorded. The Phonological task required the subjects to indicate via button press whether highly frequent German nouns like ‘Zebra’ consisted of two or three syllables. In a simple control task, participants had to indicate whether an arrow pointed left or right to control for unspecific effects. Results (1) Stimulation was a significant predictor for decision speed in the Phonological task (p = .02). Specifically, participants responded faster after 10 Hz relative to sham stimulation, but not after 16.18 Hz. (2) This effect was task specific as tACS did not significantly affect the control task (p = 0.43). (3) Participants had an increase in resting state alpha power (p = .004), which wasn’t modulated by stimulation (p = .70). (4) We found a significant event related desynchronization in the alpha band (p Conclusion The results show an improvement in a Phonological Word task after applying 10 Hz tACS over the bilateral IFG but not in simple motoric control task. This might be explained by a paradoxical facilitation effect, resulting in an ‘optimal’ level of noise for task processing ( Miniussi et al., 2013 ) or by inhibition of surrounding areas that might be competing for task resources. Since no specific effect on alpha oscillations could be found, further studies will therefore investigate effects of focal online stimulation.
Leon Sierau - One of the best experts on this subject based on the ideXlab platform.
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after effects of 10 hz tacs over the prefrontal cortex on Phonological Word decisions
Brain Stimulation, 2019Co-Authors: V Moliadze, Leon Sierau, Ekaterina Lyzhko, T Stenner, Michael Werchowski, Michael Siniatchkin, Gesa HartwigsenAbstract:Abstract Introduction Previous work in the language domain has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (pIFG) in the prefrontal cortex impaired Phonological decision-making, arguing for a causal contribution of the bilateral pIFG to Phonological processing. However, the neurophysiological correlates of these effects are unclear. The present study addressed the question whether neural activity in the prefrontal cortex could be modulated by 10 Hz tACS and how this would affect Phonological decisions. Methods In three sessions, 24 healthy participants received tACS at 10 Hz or 16.18 Hz (control frequency) or sham stimulation over the bilateral prefrontal cortex before task processing. Resting state EEG was recorded before and after tACS. We also recorded EEG during task processing. Results Relative to sham stimulation, 10 Hz tACS significantly facilitated Phonological response speed. This effect was task-specific as tACS did not affect a simple control task. Moreover, 10 Hz tACS significantly increased theta power during Phonological decisions. The individual increase in theta power was positively correlated with the behavioral facilitation after 10 Hz tACS. Conclusion Our results show a facilitation of Phonological decisions after 10 Hz tACS over the bilateral prefrontal cortex. This might indicate that 10 Hz tACS increased task-related activity in the stimulated area to a level that was optimal for Phonological performance. The significant correlation with the individual increase in theta power suggests that the behavioral facilitation might be related to increased theta power during language processing.
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p108 effects of 10 hz tacs on Phonological language processing
Clinical Neurophysiology, 2018Co-Authors: T Stenner, Gesa Hartwigsen, Leon Sierau, Michael Werchowski, Michael Siniatchkin, S Matern, Christian Kaernbach, V MoliadzeAbstract:Introduction A previous study ( Hartwigsen et al., 2010 ) has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (IFG) impaired performance in a Phonological decision-making task. However, it is unclear whether the neurodisruptive effect of 10 Hz-rTMS is caused by entrainment of alpha-oscillations. To address this issue, the present study investigated the following questions: (1) Are alpha-oscillations in the IFG functionally relevant for Phonological processing? (2) Can we enhance alpha activity in the IFG using 10 Hz tACS? and (3) Does enhancement of alpha activity cause behavioral disruption? Methods 24 right-handed, healthy participants (12 male, age range: 18–30 years, mean = 21.96, SD = 3.36) participated in the study. 9 mm2 circular sponge electrodes were placed over the bilateral IFG. In three separate sessions, 1 mA tACS at 10 Hz or 16.18 Hz or sham stimulation were applied for 20 min. Before and after stimulation, 5 min of resting state EEG was recorded. The Phonological task required the subjects to indicate via button press whether highly frequent German nouns like ‘Zebra’ consisted of two or three syllables. In a simple control task, participants had to indicate whether an arrow pointed left or right to control for unspecific effects. Results (1) Stimulation was a significant predictor for decision speed in the Phonological task (p = .02). Specifically, participants responded faster after 10 Hz relative to sham stimulation, but not after 16.18 Hz. (2) This effect was task specific as tACS did not significantly affect the control task (p = 0.43). (3) Participants had an increase in resting state alpha power (p = .004), which wasn’t modulated by stimulation (p = .70). (4) We found a significant event related desynchronization in the alpha band (p Conclusion The results show an improvement in a Phonological Word task after applying 10 Hz tACS over the bilateral IFG but not in simple motoric control task. This might be explained by a paradoxical facilitation effect, resulting in an ‘optimal’ level of noise for task processing ( Miniussi et al., 2013 ) or by inhibition of surrounding areas that might be competing for task resources. Since no specific effect on alpha oscillations could be found, further studies will therefore investigate effects of focal online stimulation.
