- Email: [email protected]
Effects of montage configuration on cortical excitability
Abstracts / Brain Stimulation 7 (2014) e1ee16 c
Department of Public Health, Weill Cornell Medical College, New York, New York, USA *E-mail: [email protected].
We demonstrate the utility of the self-administered Patient Health Questionnaire (PHQ-9) in assessing depression severity and treatment response of depressed individuals receiving TMS. We compared PHQ-9 responses with those of the observer-rated 17Item Hamilton Depression Rating Scale (HAMD). We measured both HAMD and PHQ-9 at weekly intervals during a 5-week course of 10Hz rTMS targeting the left Dorsolateral Prefrontal Cortex (DLPFC).We compared the change of the HAMD and PHQ-9 from beginning to end of treatment as well as the weekly time course of each scale, in 38 participants. On average, the HAMD decreased 21% during treatment while the PHQ-9 decreased 36%. The HAMD correlated highly with the PHQ-9 (r¼ 0.80, p<.0001) across all subjects and all time points. The HAMD and the PHQ-9 correlated more strongly in subjects who responded to TMS (as measured by a > 50% reduction in HAMD).The PHQ-9 is a robust measure of depressive symptom severity and response to TMS and can be used as an individual measure of depression severity throughout a course of TMS.
49 Effects of montage configuration on cortical excitability Jessica Berard a,*, Isis E. Martínez-Hernández b, Abhishek Datta c, Marom Bikson c, John W. Krakauer d, Heidi Schambra b a Motor Performance Laboratory, Department of Neurology, Columbia University, New York, NY 10032 b Motor Performance Laboratory, Department of Rehabilitation Medicine, Columbia University, New York, NY 10032 c Department of Biomedical Engineering, The City College of the City University of New York New York, NY, 10031 d Department of Neurology, Johns Hopkins University, Baltimore, Maryland, 21218 *E-mail: [email protected]. Transcranial direct stimulation (tDCS) is applied using various electrode configurations (montages). However, it is unclear to what extent montage configuration has differential effects on cortical excitability. Here, we used transcranial magnetic stimulation (TMS) to characterize the focal and remote neurophysiological changes induced by 5 separate tDCS montage configurations. Fourteen healthy subjects (8M:6F; 31.8 9.7 years) were stimulated with different montages over 10 daily sessions. 1mA anodal tDCS was applied for 20 min to the left motor cortex (M1). The cathode position was contralateral M1 (M1-M1), contralateral supraorbital forehead (M1-SO), ipsilateral deltoid (M1-Delt), or surrounding left motor cortical areas (high-definition; 4x1). Sham stimulation was applied using one of these randomly selected configurations. In the first 5 sessions, TMS was used to probe one hemisphere’s first dorsal interosseus (FDI) representation. In the second 5 sessions, the homologous FDI cortical representation was probed. Measures of intracortical and interhemispheric inhibition were assessed at baseline, immediately post-stimulation, and 30 minutes post-stimulation. Results were analyzed using a 3x5 mixed design ANOVA with 1 betweenfactor (montage) and one within-factor (time). We found no main effect of montage in any neurophysiological outcome, for either hemisphere. We found a main effect of time on cortical excitability and long-interval cortical inhibition (LICI) of left M1, but no interaction between time and montage. These preliminary data did not reveal an effect of montage on bihemispheric motor cortical activity. It is possible that response variance led to no significant differences between groups.
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50 Bursts of high frequency repetitive transcranial magnetic stimulation suppress ongoing seizures and augment lorazepam efficacy in a rat kainate status epilepticus model Roman Gersner a, Sameer C. Dhamne a, Abraham Zangen b, Alvaro Pascual-Leone c, Alexander Rotenberg a,c,* a Department of Neurology, Division of Epilepsy and Clinical Neurophysiology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115 b Department of Life Sciences and the Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel c Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115 *E-mail: [email protected]. Background: Status epilepticus (SE) is a condition of prolonged, and often drug-resistant, seizures. Successful pharmacologic SE treatment often leads to sedation and respiratory depression. A non-pharmacologic and non-sedating SE therapeutic thus remains an important unmet need. Repetitive transcranial magnetic stimulation (rTMS) is emerging as a means to suppress seizures, but has not been extensively studies in SE models. Methods: We summarize two experiments using the rat intraperitoneal kainate (KA) under urethane anesthesia model. In both, EEG was collected continuously after KA injection. In the first, we tested whether high-frequency rTMS suppresses seizures. Rats were divided into three groups to receive (1) KA+verum rTMS (10 bursts of 20 Hz, 30 sec ITI, 80% MO intensity, N¼9), (2) KA+sham rTMS (N¼9) and (3) saline+sham rTMS (N¼6). Next, we tested whether rTMS interacts synergistically with lorazepam (LZP), a first-line SE treatment. Rats were divided into three groups to receive: (1) two LZP half-doses (LZP+LZP, N¼10), (2) half-dose LZP and saline (LZP+Saline, N¼10) or (3) half-dose LZP and saline (LZP+rTMS, N¼6). Results: In the first experiment, we found that verum rTMS resulted in a 3-fold decrease in epileptic spike frequency during the stimulation block, (p<0.01) but epileptic spikes resumed once stimulation stopped. In the second experiment, we found that halfdose LZP together with rTMS was as effective in suppressing epileptic spikes during and after treatment as a full LZP dose (p<0.01). Conclusion: We report that high frequency rTMS has modest antiepileptic potential alone, but acts synergistically with LZP to suppress seizures.
51 Subcranial magnetic stimulation: a novel method of focal, noninvasive deep brain neuromodulation for the treatment of posttraumatic stress disorder. Jonathan R. Young BA a,b,d,*, Artem Rozkov MS c,d, Zhao Li MS c,d, Oliver Young MS d, Tim Barber BS d, Pascal Wallisch PhD e a Stony Brook University School of Medicine, Stony Brook, NY 11790 USA b Cognitive Neurophysiology Research Group, Department of Neurology, New York University School of Medicine, New York, NY 10016 USA c Department of Electrical and Computer Engineering, Polytechnic Institute of New York University, Brooklyn, NY 11201 USA d NeuTx Research Group, Stony Brook, NY 11790 USA e Computational Neuroimaging Laboratory, Center for Neural Science, Department of Psychology, New York University, New York, NY 10003 USA *E-mail: [email protected]. Current treatment options for post-traumatic stress disorder (PTSD) have only limited efficacy. This is due to the fact that the
Department of Public Health, Weill Cornell Medical College, New York, New York, USA *E-mail: [email protected].
We demonstrate the utility of the self-administered Patient Health Questionnaire (PHQ-9) in assessing depression severity and treatment response of depressed individuals receiving TMS. We compared PHQ-9 responses with those of the observer-rated 17Item Hamilton Depression Rating Scale (HAMD). We measured both HAMD and PHQ-9 at weekly intervals during a 5-week course of 10Hz rTMS targeting the left Dorsolateral Prefrontal Cortex (DLPFC).We compared the change of the HAMD and PHQ-9 from beginning to end of treatment as well as the weekly time course of each scale, in 38 participants. On average, the HAMD decreased 21% during treatment while the PHQ-9 decreased 36%. The HAMD correlated highly with the PHQ-9 (r¼ 0.80, p<.0001) across all subjects and all time points. The HAMD and the PHQ-9 correlated more strongly in subjects who responded to TMS (as measured by a > 50% reduction in HAMD).The PHQ-9 is a robust measure of depressive symptom severity and response to TMS and can be used as an individual measure of depression severity throughout a course of TMS.
49 Effects of montage configuration on cortical excitability Jessica Berard a,*, Isis E. Martínez-Hernández b, Abhishek Datta c, Marom Bikson c, John W. Krakauer d, Heidi Schambra b a Motor Performance Laboratory, Department of Neurology, Columbia University, New York, NY 10032 b Motor Performance Laboratory, Department of Rehabilitation Medicine, Columbia University, New York, NY 10032 c Department of Biomedical Engineering, The City College of the City University of New York New York, NY, 10031 d Department of Neurology, Johns Hopkins University, Baltimore, Maryland, 21218 *E-mail: [email protected]. Transcranial direct stimulation (tDCS) is applied using various electrode configurations (montages). However, it is unclear to what extent montage configuration has differential effects on cortical excitability. Here, we used transcranial magnetic stimulation (TMS) to characterize the focal and remote neurophysiological changes induced by 5 separate tDCS montage configurations. Fourteen healthy subjects (8M:6F; 31.8 9.7 years) were stimulated with different montages over 10 daily sessions. 1mA anodal tDCS was applied for 20 min to the left motor cortex (M1). The cathode position was contralateral M1 (M1-M1), contralateral supraorbital forehead (M1-SO), ipsilateral deltoid (M1-Delt), or surrounding left motor cortical areas (high-definition; 4x1). Sham stimulation was applied using one of these randomly selected configurations. In the first 5 sessions, TMS was used to probe one hemisphere’s first dorsal interosseus (FDI) representation. In the second 5 sessions, the homologous FDI cortical representation was probed. Measures of intracortical and interhemispheric inhibition were assessed at baseline, immediately post-stimulation, and 30 minutes post-stimulation. Results were analyzed using a 3x5 mixed design ANOVA with 1 betweenfactor (montage) and one within-factor (time). We found no main effect of montage in any neurophysiological outcome, for either hemisphere. We found a main effect of time on cortical excitability and long-interval cortical inhibition (LICI) of left M1, but no interaction between time and montage. These preliminary data did not reveal an effect of montage on bihemispheric motor cortical activity. It is possible that response variance led to no significant differences between groups.
e15
50 Bursts of high frequency repetitive transcranial magnetic stimulation suppress ongoing seizures and augment lorazepam efficacy in a rat kainate status epilepticus model Roman Gersner a, Sameer C. Dhamne a, Abraham Zangen b, Alvaro Pascual-Leone c, Alexander Rotenberg a,c,* a Department of Neurology, Division of Epilepsy and Clinical Neurophysiology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115 b Department of Life Sciences and the Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel c Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115 *E-mail: [email protected]. Background: Status epilepticus (SE) is a condition of prolonged, and often drug-resistant, seizures. Successful pharmacologic SE treatment often leads to sedation and respiratory depression. A non-pharmacologic and non-sedating SE therapeutic thus remains an important unmet need. Repetitive transcranial magnetic stimulation (rTMS) is emerging as a means to suppress seizures, but has not been extensively studies in SE models. Methods: We summarize two experiments using the rat intraperitoneal kainate (KA) under urethane anesthesia model. In both, EEG was collected continuously after KA injection. In the first, we tested whether high-frequency rTMS suppresses seizures. Rats were divided into three groups to receive (1) KA+verum rTMS (10 bursts of 20 Hz, 30 sec ITI, 80% MO intensity, N¼9), (2) KA+sham rTMS (N¼9) and (3) saline+sham rTMS (N¼6). Next, we tested whether rTMS interacts synergistically with lorazepam (LZP), a first-line SE treatment. Rats were divided into three groups to receive: (1) two LZP half-doses (LZP+LZP, N¼10), (2) half-dose LZP and saline (LZP+Saline, N¼10) or (3) half-dose LZP and saline (LZP+rTMS, N¼6). Results: In the first experiment, we found that verum rTMS resulted in a 3-fold decrease in epileptic spike frequency during the stimulation block, (p<0.01) but epileptic spikes resumed once stimulation stopped. In the second experiment, we found that halfdose LZP together with rTMS was as effective in suppressing epileptic spikes during and after treatment as a full LZP dose (p<0.01). Conclusion: We report that high frequency rTMS has modest antiepileptic potential alone, but acts synergistically with LZP to suppress seizures.
51 Subcranial magnetic stimulation: a novel method of focal, noninvasive deep brain neuromodulation for the treatment of posttraumatic stress disorder. Jonathan R. Young BA a,b,d,*, Artem Rozkov MS c,d, Zhao Li MS c,d, Oliver Young MS d, Tim Barber BS d, Pascal Wallisch PhD e a Stony Brook University School of Medicine, Stony Brook, NY 11790 USA b Cognitive Neurophysiology Research Group, Department of Neurology, New York University School of Medicine, New York, NY 10016 USA c Department of Electrical and Computer Engineering, Polytechnic Institute of New York University, Brooklyn, NY 11201 USA d NeuTx Research Group, Stony Brook, NY 11790 USA e Computational Neuroimaging Laboratory, Center for Neural Science, Department of Psychology, New York University, New York, NY 10003 USA *E-mail: [email protected]. Current treatment options for post-traumatic stress disorder (PTSD) have only limited efficacy. This is due to the fact that the