An excellent article on the state of the art of DBS by Morten L. Kringelbach and Tipu Z. Aziz. Read it here.
Dec 29, 2008
Sparking Recovery with Brain "Pacemakers"
An excellent article on the state of the art of DBS by Morten L. Kringelbach and Tipu Z. Aziz. Read it here.
Stimulus intensity dependence of cerebral blood volume changes in left frontal lobe by low-frequency rTMS to right frontal lobe: A near-infrared spec
PMID: 18992287
AUTHORS: Yoshiyuki Aoyama, Naoki Hanaoka, Masaki Kameyama, Masashi Suda, Toshimasa Sato, Mingqiao Song, Masato Fukuda, Masahiko Mikuni
AFFILIATION: Department of Psychiatry and Human Behavior, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi 371-8511, Gunma, Japan.
REFERENCE: Neurosci Res 2009 Jan 63(1):47-51
Repetitive transcranial magnetic stimulation (rTMS) has recently been widely employed for the investigation of brain function and treatment of psychiatric and neurological disorders. Although high and low stimulation frequencies are assumed to activate and deactivate brain function, respectively, the optimal parameters of rTMS for treatment of depression have been determined only on the basis of their clinical efficacy. In this study, we administered a 60-s low-frequency rTMS of three grades low intensities over the right dorsolateral prefrontal cortex (DLPFC) in 10 healthy volunteers, and monitored functional changes of the contralateral DLPFC by near-infrared spectroscopy (NIRS) during and immediately after rTMS. Obtained results demonstrated significant [oxy-Hb] decreases during rTMS, and significant differences in the time courses of [oxy-Hb] changes among three stimulus intensities , that is, [oxy-Hb] decreases were most prominent during the latter half of the stimulation and the first 30s of poststimulation only at 15mm condition (58% intensity). These results suggest that monitoring of brain functional changes due to rTMS using NIRS is useful for elucidating the brain mechanisms underlying the clinical effects of rTMS , and the effects of rTMS over contralateral DLPFC are obtained if the stimulus intensities are more than one-half of the motor thresholds.
AUTHORS: Yoshiyuki Aoyama, Naoki Hanaoka, Masaki Kameyama, Masashi Suda, Toshimasa Sato, Mingqiao Song, Masato Fukuda, Masahiko Mikuni
AFFILIATION: Department of Psychiatry and Human Behavior, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi 371-8511, Gunma, Japan.
REFERENCE: Neurosci Res 2009 Jan 63(1):47-51
Repetitive transcranial magnetic stimulation (rTMS) has recently been widely employed for the investigation of brain function and treatment of psychiatric and neurological disorders. Although high and low stimulation frequencies are assumed to activate and deactivate brain function, respectively, the optimal parameters of rTMS for treatment of depression have been determined only on the basis of their clinical efficacy. In this study, we administered a 60-s low-frequency rTMS of three grades low intensities over the right dorsolateral prefrontal cortex (DLPFC) in 10 healthy volunteers, and monitored functional changes of the contralateral DLPFC by near-infrared spectroscopy (NIRS) during and immediately after rTMS. Obtained results demonstrated significant [oxy-Hb] decreases during rTMS, and significant differences in the time courses of [oxy-Hb] changes among three stimulus intensities , that is, [oxy-Hb] decreases were most prominent during the latter half of the stimulation and the first 30s of poststimulation only at 15mm condition (58% intensity). These results suggest that monitoring of brain functional changes due to rTMS using NIRS is useful for elucidating the brain mechanisms underlying the clinical effects of rTMS , and the effects of rTMS over contralateral DLPFC are obtained if the stimulus intensities are more than one-half of the motor thresholds.
Daily left prefrontal repetitive transcranial magnetic stimulation in the acute treatment of major depression: clinical predictors of outcome in a multisite, randomized controlled clinical trial
PMID: 18704101
AUTHORS: Sarah H Lisanby, Mustafa M Husain, Peter B Rosenquist, Daniel Maixner, Rosben Gutierrez, Andrew Krystal, William Gilmer, Lauren B Marangell, Scott Aaronson, Zafiris J Daskalakis, Randolph Canterbury, Elliott Richelson, Harold A Sackeim, Mark S George
AFFILIATION: 1Division of Brain Stimulation and Therapeutic Modulation, Department of Psychiatry, Columbia University/New York State Psychiatric Institute, New York, NY, USA.
REFERENCE: Neuropsychopharmacology 2009 Jan 34(2):522-34
Randomized controlled trials support the antidepressant efficacy of transcranial magnetic stimulation (TMS); however, there is individual variability in the magnitude of response. Examination of response predictors has been hampered by methodological limitations such as small sample sizes and single-site study designs. Data from a multisite sham- controlled trial of the antidepressant efficacy of TMS provided an opportunity to examine predictors of acute outcome. An open-label extension for patients who failed to improve provided the opportunity for confirmatory analysis. Treatment was administered to the left dorsolateral prefrontal cortex at 10 pulses per second, 120% of motor threshold, for a total of 3000 pulses per day. Change on the Montgomery- Asberg Depression Rating Scale after 4 weeks was the primary efficacy outcome. A total of 301 patients with nonpsychotic unipolar major depression at 23 centers were randomized to active or sham TMS. Univariate predictor analyses showed that the degree of prior treatment resistance in the current episode was a predictor of positive treatment outcome in both the controlled study and the open-label extension trial In the randomized trial, shorter duration of current episode was also associated with a better outcome. In the open-label extension study, absence of anxiety disorder comorbidity was associated with an improved outcome, but duration of current episode was not. The number of prior treatment failures was the strongest predictor for positive response to acute treatment with TMS. Shorter duration of current illness and lack of anxiety comorbidity may also confer an increased likelihood of good antidepressant response to TMS.Neuropsychopharmacology (2009) 34, 522- 534; doi:10.1038/npp.2008.118; published online 13 August 2008.
AUTHORS: Sarah H Lisanby, Mustafa M Husain, Peter B Rosenquist, Daniel Maixner, Rosben Gutierrez, Andrew Krystal, William Gilmer, Lauren B Marangell, Scott Aaronson, Zafiris J Daskalakis, Randolph Canterbury, Elliott Richelson, Harold A Sackeim, Mark S George
AFFILIATION: 1Division of Brain Stimulation and Therapeutic Modulation, Department of Psychiatry, Columbia University/New York State Psychiatric Institute, New York, NY, USA.
REFERENCE: Neuropsychopharmacology 2009 Jan 34(2):522-34
Randomized controlled trials support the antidepressant efficacy of transcranial magnetic stimulation (TMS); however, there is individual variability in the magnitude of response. Examination of response predictors has been hampered by methodological limitations such as small sample sizes and single-site study designs. Data from a multisite sham- controlled trial of the antidepressant efficacy of TMS provided an opportunity to examine predictors of acute outcome. An open-label extension for patients who failed to improve provided the opportunity for confirmatory analysis. Treatment was administered to the left dorsolateral prefrontal cortex at 10 pulses per second, 120% of motor threshold, for a total of 3000 pulses per day. Change on the Montgomery- Asberg Depression Rating Scale after 4 weeks was the primary efficacy outcome. A total of 301 patients with nonpsychotic unipolar major depression at 23 centers were randomized to active or sham TMS. Univariate predictor analyses showed that the degree of prior treatment resistance in the current episode was a predictor of positive treatment outcome in both the controlled study and the open-label extension trial In the randomized trial, shorter duration of current episode was also associated with a better outcome. In the open-label extension study, absence of anxiety disorder comorbidity was associated with an improved outcome, but duration of current episode was not. The number of prior treatment failures was the strongest predictor for positive response to acute treatment with TMS. Shorter duration of current illness and lack of anxiety comorbidity may also confer an increased likelihood of good antidepressant response to TMS.Neuropsychopharmacology (2009) 34, 522- 534; doi:10.1038/npp.2008.118; published online 13 August 2008.
Repetitive TMS combined with exposure therapy for PTSD: A preliminary study
PMID: 18455908
AUTHORS: Elizabeth A Osuch, Brenda E Benson, David A Luckenbaugh, Marilla Geraci, Robert M Post, Una McCann
AFFILIATION: Biological Psychiatry Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MA, United States.
REFERENCE: J Anxiety Disord 2009 Jan 23(1):54-9
Treatment for anxiety and post-traumatic stress disorder (PTSD) includes exposure therapy and medications, but some patients are refractory. Few studies of repetitive transcranial magnetic stimulation (rTMS) for anxiety or PTSD exist. In this preliminary report, rTMS was combined with exposure therapy for PTSD. Nine subjects with chronic, treatment- refractory PTSD were studied in a placebo-controlled, crossover design of imaginal exposure therapy with rTMS (1Hz) versus sham. PTSD symptoms , serum and 24h urine were obtained and analyzed. Effect sizes for PTSD symptoms were determined using Cohen's d. Active rTMS showed a larger effect size of improvement for hyperarousal symptoms compared to sham; 24-h urinary norepinephrine and serum T4 increased; serum prolactin decreased. Active rTMS with exposure may have symptomatic and physiological effects. Larger studies are needed to confirm these preliminary findings and verify whether rTMS plus exposure therapy has a role in the treatment of PTSD.
AUTHORS: Elizabeth A Osuch, Brenda E Benson, David A Luckenbaugh, Marilla Geraci, Robert M Post, Una McCann
AFFILIATION: Biological Psychiatry Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MA, United States.
REFERENCE: J Anxiety Disord 2009 Jan 23(1):54-9
Treatment for anxiety and post-traumatic stress disorder (PTSD) includes exposure therapy and medications, but some patients are refractory. Few studies of repetitive transcranial magnetic stimulation (rTMS) for anxiety or PTSD exist. In this preliminary report, rTMS was combined with exposure therapy for PTSD. Nine subjects with chronic, treatment- refractory PTSD were studied in a placebo-controlled, crossover design of imaginal exposure therapy with rTMS (1Hz) versus sham. PTSD symptoms , serum and 24h urine were obtained and analyzed. Effect sizes for PTSD symptoms were determined using Cohen's d. Active rTMS showed a larger effect size of improvement for hyperarousal symptoms compared to sham; 24-h urinary norepinephrine and serum T4 increased; serum prolactin decreased. Active rTMS with exposure may have symptomatic and physiological effects. Larger studies are needed to confirm these preliminary findings and verify whether rTMS plus exposure therapy has a role in the treatment of PTSD.
Antidepressant efficacy of high-frequency transcranial magnetic stimulation over the left dorsolateral prefrontal cortex in double-blind sham-control
PMID: 18447962
AUTHORS: D J L G Schutter
AFFILIATION: Experimental Psychology, Utrecht University, Utrecht, The Netherlands.
REFERENCE: Psychol Med 2009 Jan 39(1):65-75
BACKGROUND: For more than a decade high-frequency repetitive transcranial magnetic stimulation (rTMS) has been applied to the left dorsolateral prefrontal cortex (DLPFC) in search of an alternative treatment for depression. The aim of this study was to provide an update on its clinical efficacy by performing a meta-analysis involving double -blind sham-controlled studies.MethodA literature search was conducted in the databases PubMed and Web of Science in the period between January 1980 and November 2007 with the search terms 'depression' and ' transcranial magnetic stimulation'. Thirty double-blind sham-controlled parallel studies with 1164 patients comparing the percentage change in depression scores from baseline to endpoint of active versus sham treatment were included. A random effects meta-analysis was performed to investigate the clinical efficacy of fast-frequency rTMS over the left DLPFC in depression. RESULTS: The test for heterogeneity was not significant (QT=30.46, p=0.39). A significant overall weighted mean effect size, d=0.39 [95% confidence interval (CI) 0.25-0.54], for active treatment was observed (z=6.52, p<0.0001). Medication resistance and intensity of rTMS did not play a role in the effect size. CONCLUSIONS: These findings show that high-frequency rTMS over the left DLPFC is superior to sham in the treatment of depression. The effect size is robust and comparable to at least a subset of commercially available antidepressant drug agents. Current limitations and future prospects are discussed.
AUTHORS: D J L G Schutter
AFFILIATION: Experimental Psychology, Utrecht University, Utrecht, The Netherlands.
REFERENCE: Psychol Med 2009 Jan 39(1):65-75
BACKGROUND: For more than a decade high-frequency repetitive transcranial magnetic stimulation (rTMS) has been applied to the left dorsolateral prefrontal cortex (DLPFC) in search of an alternative treatment for depression. The aim of this study was to provide an update on its clinical efficacy by performing a meta-analysis involving double -blind sham-controlled studies.MethodA literature search was conducted in the databases PubMed and Web of Science in the period between January 1980 and November 2007 with the search terms 'depression' and ' transcranial magnetic stimulation'. Thirty double-blind sham-controlled parallel studies with 1164 patients comparing the percentage change in depression scores from baseline to endpoint of active versus sham treatment were included. A random effects meta-analysis was performed to investigate the clinical efficacy of fast-frequency rTMS over the left DLPFC in depression. RESULTS: The test for heterogeneity was not significant (QT=30.46, p=0.39). A significant overall weighted mean effect size, d=0.39 [95% confidence interval (CI) 0.25-0.54], for active treatment was observed (z=6.52, p<0.0001). Medication resistance and intensity of rTMS did not play a role in the effect size. CONCLUSIONS: These findings show that high-frequency rTMS over the left DLPFC is superior to sham in the treatment of depression. The effect size is robust and comparable to at least a subset of commercially available antidepressant drug agents. Current limitations and future prospects are discussed.
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