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Transcranial Direct Current Stimulation of Pre-Supplementary Motor Area for SSRI resistant OCD
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Abstracts / Brain Stimulation 8 (2015) 360e377
spasticity in 4 post-stroke subjects that affected tonic stretch reflex threshold (TSRT) [2], i.e., the joint angle at which the stretch reflex begins to act due to the descending and segmental influences on motoneurons. The rectangular (4.5 cm 9 cm) electrodes were placed on each side of the spine (5 cm apart) over the paravertebral skin at the twelfth thoracic and first lumbar vertebral levels [3]. We found that only the high frequency (2100 Hz) sinusoidal stimulation (HFSS) and not the low frequency sinusoidal stimulation (LFSS) (20Hz) significantly affected the TSRT during tsACS application (45mins). LFSS showed significant aftereffects only after 45mins of tsACS application. Therefore, HFSS and LFSS may involve different mechanisms based on the ion channel distributions and their response properties in the neural tissue of the dorsal column [1].
References 1. Dutta A , Nitsche MA . “State-space analysis of Hodgkin-Huxley axonal neural mass model during subthreshold high frequency alternating current stimulation”. IEEE/EMBS NER Conference; 2013. 2. Mullick AA , Musampa NK , Feldman AG , Levin MF . “Stretch reflex spatial threshold measure discriminates between spasticity and rigidity”. Clin. Neurophys 2013;124(4):740e51. 3. Wang RY, Chan RC , Tsai MW . “Effects of thoraco-lumbar electric sensory stimulation on knee extensor spasticity of persons who survived cerebrovascular accident (CVA)”. J Rehabil Res Dev 2000;37(1):73e9.
205 Maturation of short-interval inhibitory and excitatory circuits in the human primary motor cortex L.A. Schneider , M.R. Goldsworthy , J.P. Cole , M.C. Ridding , J.B. Pitcher Robinson Research Institute, School of Paediatrics & Reproductive Health, University of Adelaide, Australia Background: Short-interval intracortical inhibition (SICI) has been reported not to reach adult levels until the late teenage years (Mall et al., 2004; Walther et al., 2009). However, SICF contamination of SICI may have influenced these previous results (Peurala et al., 2008). Here, we examined SICI maturation by constructing SICI curves at the ISI at which SICF was lowest (i.e. the first trough; T1) (Peurala et al., 2008) in children, adolescents, and adults. Methods: 51 participants aged 8e29 years (17.7 4.4 years, mean SD) underwent paired-pulse TMS. Motor evoked potentials were recorded from the right-hand first dorsal interosseous muscle. SICF was studied at ISIs of 1.5, 1.7, 1.9, 2.1, and 2.3 ms. T1 was identified for each participant, and the corresponding ISI was used for measuring SICI. SICI curves were constructed with six conditioning stimulus intensities ranging from 60e110% of resting motor threshold. Participants were segregated into five age groups for analysis: 8e12 years; 13e15 years; 16e18 years; 19e21 years; 22e29 years. Results: Mean resting and active motor thresholds were higher in the 8e12 and 13e15 years, compared with the older groups. T1 (1.99 0.17 ms ISI), peak SICI, and the CS at which it occurred did not differ between age groups. While not statistically significant, SICF appeared greater across all ISIs in children aged 8e12 and 16e18 years. Conclusions: By assessing SICI at T1, to minimise any confounding influences of SICF, we have shown that the circuitry involved in SICI has matured by 8e12 years of age. It is possible that previous reports of a more protracted maturation were confounded by increased facilitation in younger children. Motor threshold decreases with increasing age, but our data suggest that this occurs later than previously thought.
206 Transcranial Direct Current Stimulation of Pre-Supplementary Motor Area for SSRI resistant OCD Janardhanan C. Narayanaswamy a,b*, Dania Jose a,b, Harleen Chabra b, Sri Mahavir Agarwal a,b, Basavaraj Shrinivasa a,b, Aditya Hegde a, Aditi Subramaniam b, Anushree Bose b, Sunil V. Kalmady b, Ganesan Venkatasubramanian a,b, Y.C. Janardhan Reddy a a OCD clinic, Department of Psychiatry, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India b Translational Psychiatry Laboratory, Cognitive Neurobiology Division, Neurobiology Research Centre, National Institute of Mental Health & Neurosciences, Bangalore, India * Presenting Author: [email protected] Introduction: Among the core network brain regions that subserve response inhibition, the role of Pre-supplementary motor area(pre-SMA)seems critical. In obsessive compulsive disorder(OCD), hypoactive pre-SMA has been shown to correlate with deficient response inhibition as well as more severe symptom profile.In this report, we demonstrate add-on anodal Transcranial Direct Current Stimulation (tDCS) to pre-SMA resulting in significant clinical improvement in two patients who had OCD resistant to SSRIs. Methods: Two right-handed patients with DSM IV OCD(both the patients had “forbidden thoughts” consisting of aggressive/sexual/ blasphemous obsessions)[39 years female,7 years of illness, Yale Brown Obsessive Compulsive Scale(YBOCS)score of 25, failed 2 SSRIs;24 years male,3 years of illness,YBOCS score of 30,failed 3 SSRIs] were administered tDCS using a standard equipment (TCT device model no.M101-R-2012-V13,www.trans-cranial.com)as per established protocol with twice a day schedule(separated by at least 3-hours) for 10days keeping the medications unchanged.For one patient, pre and post-tDCS fMRI(3T) with response inhibition based cognitive activation task (Go/No-go task)was used to assess the neurohemodynamic changes in the pre-SMA. Results: Following tDCS, there was a significant reduction in the OCD severity in both the patients (52% and 40% reduction in YBOCS score respectively). The clinical improvement sustained for 6 weeks and 4 weeks respectively, till their latest follow up assessment. Concurrently, there was significant increase in left SMA activation in the No-go minus Go contrast in post tDCS compared to the pretDCS condition(uncorrected p<0.001)(MNI co-ordinates X¼2,Y¼28,Z¼64; Brodmann area 6,cluster size¼89) Discussion: To the best of our knowledge, this is the first demonstration of safe and successful use of add-on tDCS for SSRI-resistant OCD. Significant increase in the left SMA activity after tDCS during response inhibition condition might indicate that it could have resulted in efficient response inhibition leading to clinical improvement. Further systematic evaluation using shamcontrolled studies are required to explore the utility of tDCS in OCD.
207 Usefulness of interleaving programing in pallidal stimulation for Parkinson’s disease Atsushi Umemura , Genko Oyama , Yasushi Shimo , Asuka Nakajima , Takayuki Jo , Madoka Nakajima , Hisato Ishii , Hajime Arai , Nobutaka Hattori Department of Research and Therapeutics for Movement Disorder, Neurology, and Neurosurgery, Juntendo University Graduate School of Medicine, Tokyo, Japan Recently, globus pallidus internus (GPi) has been reevaluated as an effective target of deep brain stimulation (DBS) for Parkinson’s disease (PD). It is known that stimulation of the ventral GPi improves dyskinesia, however deteriorates gait and akinesia. On the
Abstracts / Brain Stimulation 8 (2015) 360e377
spasticity in 4 post-stroke subjects that affected tonic stretch reflex threshold (TSRT) [2], i.e., the joint angle at which the stretch reflex begins to act due to the descending and segmental influences on motoneurons. The rectangular (4.5 cm 9 cm) electrodes were placed on each side of the spine (5 cm apart) over the paravertebral skin at the twelfth thoracic and first lumbar vertebral levels [3]. We found that only the high frequency (2100 Hz) sinusoidal stimulation (HFSS) and not the low frequency sinusoidal stimulation (LFSS) (20Hz) significantly affected the TSRT during tsACS application (45mins). LFSS showed significant aftereffects only after 45mins of tsACS application. Therefore, HFSS and LFSS may involve different mechanisms based on the ion channel distributions and their response properties in the neural tissue of the dorsal column [1].
References 1. Dutta A , Nitsche MA . “State-space analysis of Hodgkin-Huxley axonal neural mass model during subthreshold high frequency alternating current stimulation”. IEEE/EMBS NER Conference; 2013. 2. Mullick AA , Musampa NK , Feldman AG , Levin MF . “Stretch reflex spatial threshold measure discriminates between spasticity and rigidity”. Clin. Neurophys 2013;124(4):740e51. 3. Wang RY, Chan RC , Tsai MW . “Effects of thoraco-lumbar electric sensory stimulation on knee extensor spasticity of persons who survived cerebrovascular accident (CVA)”. J Rehabil Res Dev 2000;37(1):73e9.
205 Maturation of short-interval inhibitory and excitatory circuits in the human primary motor cortex L.A. Schneider , M.R. Goldsworthy , J.P. Cole , M.C. Ridding , J.B. Pitcher Robinson Research Institute, School of Paediatrics & Reproductive Health, University of Adelaide, Australia Background: Short-interval intracortical inhibition (SICI) has been reported not to reach adult levels until the late teenage years (Mall et al., 2004; Walther et al., 2009). However, SICF contamination of SICI may have influenced these previous results (Peurala et al., 2008). Here, we examined SICI maturation by constructing SICI curves at the ISI at which SICF was lowest (i.e. the first trough; T1) (Peurala et al., 2008) in children, adolescents, and adults. Methods: 51 participants aged 8e29 years (17.7 4.4 years, mean SD) underwent paired-pulse TMS. Motor evoked potentials were recorded from the right-hand first dorsal interosseous muscle. SICF was studied at ISIs of 1.5, 1.7, 1.9, 2.1, and 2.3 ms. T1 was identified for each participant, and the corresponding ISI was used for measuring SICI. SICI curves were constructed with six conditioning stimulus intensities ranging from 60e110% of resting motor threshold. Participants were segregated into five age groups for analysis: 8e12 years; 13e15 years; 16e18 years; 19e21 years; 22e29 years. Results: Mean resting and active motor thresholds were higher in the 8e12 and 13e15 years, compared with the older groups. T1 (1.99 0.17 ms ISI), peak SICI, and the CS at which it occurred did not differ between age groups. While not statistically significant, SICF appeared greater across all ISIs in children aged 8e12 and 16e18 years. Conclusions: By assessing SICI at T1, to minimise any confounding influences of SICF, we have shown that the circuitry involved in SICI has matured by 8e12 years of age. It is possible that previous reports of a more protracted maturation were confounded by increased facilitation in younger children. Motor threshold decreases with increasing age, but our data suggest that this occurs later than previously thought.
206 Transcranial Direct Current Stimulation of Pre-Supplementary Motor Area for SSRI resistant OCD Janardhanan C. Narayanaswamy a,b*, Dania Jose a,b, Harleen Chabra b, Sri Mahavir Agarwal a,b, Basavaraj Shrinivasa a,b, Aditya Hegde a, Aditi Subramaniam b, Anushree Bose b, Sunil V. Kalmady b, Ganesan Venkatasubramanian a,b, Y.C. Janardhan Reddy a a OCD clinic, Department of Psychiatry, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India b Translational Psychiatry Laboratory, Cognitive Neurobiology Division, Neurobiology Research Centre, National Institute of Mental Health & Neurosciences, Bangalore, India * Presenting Author: [email protected] Introduction: Among the core network brain regions that subserve response inhibition, the role of Pre-supplementary motor area(pre-SMA)seems critical. In obsessive compulsive disorder(OCD), hypoactive pre-SMA has been shown to correlate with deficient response inhibition as well as more severe symptom profile.In this report, we demonstrate add-on anodal Transcranial Direct Current Stimulation (tDCS) to pre-SMA resulting in significant clinical improvement in two patients who had OCD resistant to SSRIs. Methods: Two right-handed patients with DSM IV OCD(both the patients had “forbidden thoughts” consisting of aggressive/sexual/ blasphemous obsessions)[39 years female,7 years of illness, Yale Brown Obsessive Compulsive Scale(YBOCS)score of 25, failed 2 SSRIs;24 years male,3 years of illness,YBOCS score of 30,failed 3 SSRIs] were administered tDCS using a standard equipment (TCT device model no.M101-R-2012-V13,www.trans-cranial.com)as per established protocol with twice a day schedule(separated by at least 3-hours) for 10days keeping the medications unchanged.For one patient, pre and post-tDCS fMRI(3T) with response inhibition based cognitive activation task (Go/No-go task)was used to assess the neurohemodynamic changes in the pre-SMA. Results: Following tDCS, there was a significant reduction in the OCD severity in both the patients (52% and 40% reduction in YBOCS score respectively). The clinical improvement sustained for 6 weeks and 4 weeks respectively, till their latest follow up assessment. Concurrently, there was significant increase in left SMA activation in the No-go minus Go contrast in post tDCS compared to the pretDCS condition(uncorrected p<0.001)(MNI co-ordinates X¼2,Y¼28,Z¼64; Brodmann area 6,cluster size¼89) Discussion: To the best of our knowledge, this is the first demonstration of safe and successful use of add-on tDCS for SSRI-resistant OCD. Significant increase in the left SMA activity after tDCS during response inhibition condition might indicate that it could have resulted in efficient response inhibition leading to clinical improvement. Further systematic evaluation using shamcontrolled studies are required to explore the utility of tDCS in OCD.
207 Usefulness of interleaving programing in pallidal stimulation for Parkinson’s disease Atsushi Umemura , Genko Oyama , Yasushi Shimo , Asuka Nakajima , Takayuki Jo , Madoka Nakajima , Hisato Ishii , Hajime Arai , Nobutaka Hattori Department of Research and Therapeutics for Movement Disorder, Neurology, and Neurosurgery, Juntendo University Graduate School of Medicine, Tokyo, Japan Recently, globus pallidus internus (GPi) has been reevaluated as an effective target of deep brain stimulation (DBS) for Parkinson’s disease (PD). It is known that stimulation of the ventral GPi improves dyskinesia, however deteriorates gait and akinesia. On the