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Prolonged continuous theta-burst stimulation is more analgesic than ‘classical’ high frequency repetitive transcranial magnetic stimulation
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Abstracts / Brain Stimulation 8 (2015) 412e427
depression. The several treatment parameters have also varied considerably between studies and reflect the lack of consensus for optimal parameters for depression. Whilst few reports have linked patterns of rTMS response to some treatment parameters, the relationship between treatment parameters and efficacy remains to be elucidated. Furthermore, unlike several trials and meta-analyses, this analysis will exclude older depressed samples with potentially different neuropathologies that may confound findings. Methods: PubMed was used to search for peer-reviewed studies published between August 1975 and October 2014 on the efficacy of high-frequency, left prefrontal cortex rTMS treatment in mood disorder cohorts under 65 years-old. Twenty-two studies met eligibility criteria (N¼906; mean-age¼45) for random effects modelling and pooled effect sizes (ES) for improvement in depression ratings were generated. Moderator analyses were performed to identify predictors of between-study heterogeneity. Results: After controlling for significant publication bias (p<.05), active rTMS was significantly more efficacious in treating depression compared with sham rTMS (ES 0.9). There was significant heterogeneity in effect size (I2¼79%; p<.001). Intensity, frequency, total number of pulses or number of sessions did not significantly predict between-study heterogeneity (all p>.05). Conclusions: In keeping with the literature, rTMS has shown to be an overall efficacious treatment for depression in people aged under 65 years despite the large degree of heterogeneity in findings and parameters between clinical trials. It is possible that the parameters included here did not appear to influence efficacy, in part, due to the confounding effects of many other treatment parameters. Future analyses with larger samples should perform multivariate analyses with all predictors in a single model. Additionally, attempts to quantify trial quality and exclude poorer quality trials in analyses may prove insightful.
372 Prolonged continuous theta-burst stimulation is more analgesic than ‘classical’ high frequency repetitive transcranial magnetic stimulation D. Bouhassira a,b, S. Goudeau c, F. Poindessous-Jazat a, S. Baudic a, P. Clavelou c, X. Moisset a,d a Inserm U987, France b Versailles-Saint-Quentin University, France c Poitiers University, France d Clermont Ferrand University, France Introduction: The objectives of this study were (1) to evaluate the analgesic effects of neuronavigated intermettent (iTBS) and prolonged continuous (pcTBS) theta burst stimulation (TBS), comparing them with those of classical high frequency rTMS (10 Hz) over the left M1, (2) to elucidate the role of conditioned pain modulation (CPM) in the antinociceptive effect of rTMS and (3) to investigate possible correlations between analgesia and cortical excitability. Methods: Fourteen healthy volunteers participated in four experimental sessions, carried out in a random order (iTBS, pcTBS, 10 Hz rTMS or sham). Cold pain threshold, CPM and cortical excitability measurements were carried out before and after rTMS. Results: We found that 10 Hz rTMS and pcTBS were significantly superior to sham rTMS for the induction of cold analgesia. Moreover, pcTBS was significantly more effective than 10Hz rTMS (p¼0.026). Analgesia did not seem to be driven by changes in CPM or cortical excitability. Conclusion: Prolonged cTBS has considerable clinical potential, as it has a shorter treatment duration (by a factor 8) and stronger analgesic effects than the classical high frequency protocol. Studies
in patients are required to confirm the potential of this new stimulation paradigm for clinical applications. 373 Cerebellar and parietal anodal transcranial direct current stimulation increases mirror drawing performance Doppelmayr M. , Pixa N. Dep. Sportscience, University Mainz, Germany Introduction: Several brain areas, including the primary motor cortex, parietal areas, basal ganglia, cerebellum and many more are involved in motor adaption. While most paradigms investigating the effects of transcranial direct current stimulation (tDCS) on motor performance focus on the stimulation of the primary motor cortex, we investigated these effects with parietal and cerebellar stimulation. Methods: 39 subjects, randomly assigned to one of three stimulation groups, had to complete a series of mirror drawing tasks. Participants (n¼39, age M¼24,44; SD¼1.62) were seated in front of a mirror and geometrical figures were presented in a way that these figures were only visible via the mirror. The task was to learn to follow the lines with a pencil, held in the right hand. Beside a pre and a posttest the participants had to perform this task for 20 minutes while stimulated. Additionally a follow up test was performed 20 minutes delayed. Stimulation was applied either at parietal or cerebellar sites or as sham stimulation. 1mA with pi-electrodes (3,14cm2) was applied for 20 minutes and multiple return sites were used. Results: Analyzing the speed of the drawing a two-way ANOVA TIME (Pre, Training, Post, Follow up) and GROUP revealed significant (p < 0,05) effects for TIME and GROUP as well as a significant interaction. Participants stimulated at cerebellar locations had the shortest and the sham stimulation group the longest drawing times with increasing group differences with TIME. Concerning drawing quality a similar result emerged indicating the best results for the cerebellar stimulation group and the worst for the sham group. Again differences increased with TIME. Discussion: Taken together the data indicate that tDCS can be effective in increasing motor adaption for small hand movements. Further research is needed to disentangle cognitive and motor aspects of these results. 374 Antidepressant Effects of ECT may be related to Hippocampal Neurogenesis Colleen Loo a,b,c, Narcis Cardoner d,e,f, Harry Hallock g, Jesus Pujol d, Christos Pantelis h,i, Dennis Velakoulis h,i, Murat Yucel j, Perminder Sachdev k,l, Oren Contreras-Rodriguez d, Mikel Urretavizcaya e,f, Jose Menchon e,f, Chao Suo g,j, Petar Djuric m, Mirjana Maletic-Savatic n, Michael Valenzuela g a University of New South Wales, Sydney, Australia b St George Hospital, Sydney, Australia c Black Dog Institute, Sydney, Australia d MRI Research Unit, Hospital del Mar, CIBERSAM G21, Barcelona e Department of Psychiatry, Bellvitge University Hospital-IDIBELL, Barcelona, Spain f Instituto de Salud Carlos III, Centro de Investigación en Red de Salud Mental (CIBERSAM), Madrid, Spain g Regenerative Neuroscience Group, Brain and Mind Research Institute, University of Sydney, Sydney, Australia h Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne, Melbourne, Australia i Melbourne Health, Melbourne, Australia j Monash Clinical & Imaging Neuroscience, School of Psychological Sciences, Monash University k School of Psychiatry, University of New South Wales, Sydney, Australia
Abstracts / Brain Stimulation 8 (2015) 412e427
depression. The several treatment parameters have also varied considerably between studies and reflect the lack of consensus for optimal parameters for depression. Whilst few reports have linked patterns of rTMS response to some treatment parameters, the relationship between treatment parameters and efficacy remains to be elucidated. Furthermore, unlike several trials and meta-analyses, this analysis will exclude older depressed samples with potentially different neuropathologies that may confound findings. Methods: PubMed was used to search for peer-reviewed studies published between August 1975 and October 2014 on the efficacy of high-frequency, left prefrontal cortex rTMS treatment in mood disorder cohorts under 65 years-old. Twenty-two studies met eligibility criteria (N¼906; mean-age¼45) for random effects modelling and pooled effect sizes (ES) for improvement in depression ratings were generated. Moderator analyses were performed to identify predictors of between-study heterogeneity. Results: After controlling for significant publication bias (p<.05), active rTMS was significantly more efficacious in treating depression compared with sham rTMS (ES 0.9). There was significant heterogeneity in effect size (I2¼79%; p<.001). Intensity, frequency, total number of pulses or number of sessions did not significantly predict between-study heterogeneity (all p>.05). Conclusions: In keeping with the literature, rTMS has shown to be an overall efficacious treatment for depression in people aged under 65 years despite the large degree of heterogeneity in findings and parameters between clinical trials. It is possible that the parameters included here did not appear to influence efficacy, in part, due to the confounding effects of many other treatment parameters. Future analyses with larger samples should perform multivariate analyses with all predictors in a single model. Additionally, attempts to quantify trial quality and exclude poorer quality trials in analyses may prove insightful.
372 Prolonged continuous theta-burst stimulation is more analgesic than ‘classical’ high frequency repetitive transcranial magnetic stimulation D. Bouhassira a,b, S. Goudeau c, F. Poindessous-Jazat a, S. Baudic a, P. Clavelou c, X. Moisset a,d a Inserm U987, France b Versailles-Saint-Quentin University, France c Poitiers University, France d Clermont Ferrand University, France Introduction: The objectives of this study were (1) to evaluate the analgesic effects of neuronavigated intermettent (iTBS) and prolonged continuous (pcTBS) theta burst stimulation (TBS), comparing them with those of classical high frequency rTMS (10 Hz) over the left M1, (2) to elucidate the role of conditioned pain modulation (CPM) in the antinociceptive effect of rTMS and (3) to investigate possible correlations between analgesia and cortical excitability. Methods: Fourteen healthy volunteers participated in four experimental sessions, carried out in a random order (iTBS, pcTBS, 10 Hz rTMS or sham). Cold pain threshold, CPM and cortical excitability measurements were carried out before and after rTMS. Results: We found that 10 Hz rTMS and pcTBS were significantly superior to sham rTMS for the induction of cold analgesia. Moreover, pcTBS was significantly more effective than 10Hz rTMS (p¼0.026). Analgesia did not seem to be driven by changes in CPM or cortical excitability. Conclusion: Prolonged cTBS has considerable clinical potential, as it has a shorter treatment duration (by a factor 8) and stronger analgesic effects than the classical high frequency protocol. Studies
in patients are required to confirm the potential of this new stimulation paradigm for clinical applications. 373 Cerebellar and parietal anodal transcranial direct current stimulation increases mirror drawing performance Doppelmayr M. , Pixa N. Dep. Sportscience, University Mainz, Germany Introduction: Several brain areas, including the primary motor cortex, parietal areas, basal ganglia, cerebellum and many more are involved in motor adaption. While most paradigms investigating the effects of transcranial direct current stimulation (tDCS) on motor performance focus on the stimulation of the primary motor cortex, we investigated these effects with parietal and cerebellar stimulation. Methods: 39 subjects, randomly assigned to one of three stimulation groups, had to complete a series of mirror drawing tasks. Participants (n¼39, age M¼24,44; SD¼1.62) were seated in front of a mirror and geometrical figures were presented in a way that these figures were only visible via the mirror. The task was to learn to follow the lines with a pencil, held in the right hand. Beside a pre and a posttest the participants had to perform this task for 20 minutes while stimulated. Additionally a follow up test was performed 20 minutes delayed. Stimulation was applied either at parietal or cerebellar sites or as sham stimulation. 1mA with pi-electrodes (3,14cm2) was applied for 20 minutes and multiple return sites were used. Results: Analyzing the speed of the drawing a two-way ANOVA TIME (Pre, Training, Post, Follow up) and GROUP revealed significant (p < 0,05) effects for TIME and GROUP as well as a significant interaction. Participants stimulated at cerebellar locations had the shortest and the sham stimulation group the longest drawing times with increasing group differences with TIME. Concerning drawing quality a similar result emerged indicating the best results for the cerebellar stimulation group and the worst for the sham group. Again differences increased with TIME. Discussion: Taken together the data indicate that tDCS can be effective in increasing motor adaption for small hand movements. Further research is needed to disentangle cognitive and motor aspects of these results. 374 Antidepressant Effects of ECT may be related to Hippocampal Neurogenesis Colleen Loo a,b,c, Narcis Cardoner d,e,f, Harry Hallock g, Jesus Pujol d, Christos Pantelis h,i, Dennis Velakoulis h,i, Murat Yucel j, Perminder Sachdev k,l, Oren Contreras-Rodriguez d, Mikel Urretavizcaya e,f, Jose Menchon e,f, Chao Suo g,j, Petar Djuric m, Mirjana Maletic-Savatic n, Michael Valenzuela g a University of New South Wales, Sydney, Australia b St George Hospital, Sydney, Australia c Black Dog Institute, Sydney, Australia d MRI Research Unit, Hospital del Mar, CIBERSAM G21, Barcelona e Department of Psychiatry, Bellvitge University Hospital-IDIBELL, Barcelona, Spain f Instituto de Salud Carlos III, Centro de Investigación en Red de Salud Mental (CIBERSAM), Madrid, Spain g Regenerative Neuroscience Group, Brain and Mind Research Institute, University of Sydney, Sydney, Australia h Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne, Melbourne, Australia i Melbourne Health, Melbourne, Australia j Monash Clinical & Imaging Neuroscience, School of Psychological Sciences, Monash University k School of Psychiatry, University of New South Wales, Sydney, Australia