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1.
Article in English | MEDLINE | ID: mdl-38531486

ABSTRACT

INTRODUCTION: A substantial proportion of smokers wishing to quit do not stop smoking when using current therapies to aid cessation. Magnetic pulses to specific brain areas designated as transcranial magnetic stimulation may modulate brain activity and thereby change chemical dependencies. Deep transcranial magnetic stimulation (dTMS) with the H4 coil stimulates neuronal pathways in the lateral prefrontal cortex and insula bilaterally, areas involved in tobacco addiction. OBJECTIVE: To evaluate the efficacy and safety of dTMS with T4 coil in smoking cessation. METHODS: In a double blind, controlled clinical trial, adult smokers of at least 10 cigarettes/day were randomized to active (n = 50) versus sham dTMS (n = 50). The protocol involved up to 21 sessions administered over up to 12 weeks. Tobacco use was monitored by self-report and confirmed by expired air monoximetry (at each dTMS visit) and blood cotinine (at the screening visit and at the end of sessions). Participants completed abstinence, mood and cognition scales at determined timepoints during follow-up. RESULTS: In the intention to-treat-analysis, the cessation rate of the intervention and control groups was 14.0%. The reported side effects were as expected for this procedure. Although there were no serious adverse events, three participants were withdrawn according to safety criteria. CONCLUSION: Active treatment with dTMS H4 coil was safe but not effective for smoking cessation.


Subject(s)
Smoking Cessation , Adult , Humans , Prospective Studies , Smoking/therapy , Transcranial Magnetic Stimulation/methods , Treatment Outcome , Double-Blind Method
2.
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 40(3): 309-311, July-Sept. 2018. tab
Article in English | LILACS | ID: biblio-1039087

ABSTRACT

Objective: Theta-burst stimulation (TBS) modulates synaptic plasticity more efficiently than standard repetitive transcranial magnetic stimulation delivery and may be a promising modality for neuropsychiatric disorders such as autism spectrum disorder (ASD). At present there are few effective interventions for prefrontal cortex dysfunction in ASD. We report on an open-label, pilot study of intermittent TBS (iTBS) to target executive function deficits and restricted, repetitive behaviors in male children and adolescents with ASD. Methods: Ten right-handed, male participants, aged 9-17 years with ASD were enrolled in an open-label trial of iTBS treatment. Fifteen sessions of neuronavigated iTBS at 100% motor threshold targeting the right dorsolateral prefrontal cortex were delivered over 3 weeks. Results: Parent report scores on the Repetitive Behavior Scale Revised and the Yale-Brown Obsessive Compulsive Scale demonstrated improvements with iTBS treatment. Participants demonstrated improvements in perseverative errors on the Wisconsin Card Sorting Test and total time for the Stroop test. The iTBS treatments were well tolerated with no serious adverse effects. Conclusion: These preliminary results suggest that further controlled interventional studies of iTBS for ASD are warranted.


Subject(s)
Humans , Male , Child , Adolescent , Theta Rhythm/physiology , Transcranial Magnetic Stimulation/methods , Autism Spectrum Disorder/therapy , Pilot Projects , Treatment Outcome , Prefrontal Cortex/physiopathology , Signal Detection, Psychological , Aftercare , Autism Spectrum Disorder/physiopathology , Autism Spectrum Disorder/psychology , Obsessive Behavior/psychology , Obsessive-Compulsive Disorder/psychology
3.
Braz J Psychiatry ; 40(3): 309-311, 2018.
Article in English | MEDLINE | ID: mdl-29236921

ABSTRACT

OBJECTIVE: Theta-burst stimulation (TBS) modulates synaptic plasticity more efficiently than standard repetitive transcranial magnetic stimulation delivery and may be a promising modality for neuropsychiatric disorders such as autism spectrum disorder (ASD). At present there are few effective interventions for prefrontal cortex dysfunction in ASD. We report on an open-label, pilot study of intermittent TBS (iTBS) to target executive function deficits and restricted, repetitive behaviors in male children and adolescents with ASD. METHODS: Ten right-handed, male participants, aged 9-17 years with ASD were enrolled in an open-label trial of iTBS treatment. Fifteen sessions of neuronavigated iTBS at 100% motor threshold targeting the right dorsolateral prefrontal cortex were delivered over 3 weeks. RESULTS: Parent report scores on the Repetitive Behavior Scale Revised and the Yale-Brown Obsessive Compulsive Scale demonstrated improvements with iTBS treatment. Participants demonstrated improvements in perseverative errors on the Wisconsin Card Sorting Test and total time for the Stroop test. The iTBS treatments were well tolerated with no serious adverse effects. CONCLUSION: These preliminary results suggest that further controlled interventional studies of iTBS for ASD are warranted.


Subject(s)
Autism Spectrum Disorder/therapy , Theta Rhythm/physiology , Transcranial Magnetic Stimulation/methods , Adolescent , Aftercare , Autism Spectrum Disorder/physiopathology , Autism Spectrum Disorder/psychology , Child , Humans , Male , Obsessive Behavior/psychology , Obsessive-Compulsive Disorder/psychology , Pilot Projects , Prefrontal Cortex/physiopathology , Signal Detection, Psychological , Treatment Outcome
4.
Pain ; 157(12): 2758-2765, 2016 12.
Article in English | MEDLINE | ID: mdl-27559833

ABSTRACT

Subthalamic deep brain stimulation (STN-DBS) is used to treat refractory motor complications in Parkinson disease (PD), but its effects on nonmotor symptoms remain uncertain. Up to 80% of patients with PD may have pain relief after STN-DBS, but it is unknown whether its analgesic properties are related to potential effects on sensory thresholds or secondary to motor improvement. We have previously reported significant and long-lasting pain relief after DBS, which did not correlate with motor symptomatic control. Here we present secondary data exploring the effects of DBS on sensory thresholds in a controlled way and have explored the relationship between these changes and clinical pain and motor improvement after surgery. Thirty-seven patients were prospectively evaluated before STN-DBS and 12 months after the procedure compared with healthy controls. Compared with baseline, patients with PD showed lower thermal and mechanical detection and higher cold pain thresholds after surgery. There were no changes in heat and mechanical pain thresholds. Compared with baseline values in healthy controls, patients with PD had higher thermal and mechanical detection thresholds, which decreased after surgery toward normalization. These sensory changes had no correlation with motor or clinical pain improvement after surgery. These data confirm the existence of sensory abnormalities in PD and suggest that STN-DBS mainly influenced the detection thresholds rather than painful sensations. However, these changes may depend on the specific effects of DBS on somatosensory loops with no correlation to motor or clinical pain improvement.


Subject(s)
Consciousness Disorders/etiology , Deep Brain Stimulation/methods , Pain/etiology , Parkinson Disease/complications , Parkinson Disease/therapy , Sensory Thresholds/physiology , Subthalamus/physiology , Adult , Aged , Consciousness Disorders/therapy , Female , Humans , Hyperalgesia/therapy , Male , Middle Aged , Movement/physiology , Outcome Assessment, Health Care , Pain Management , Parkinson Disease/psychology , Physical Stimulation , Quality of Life , Statistics, Nonparametric
5.
Arch Phys Med Rehabil ; 96(4 Suppl): S156-72, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25437106

ABSTRACT

OBJECTIVE: To review the literature on the analgesic effects of repetitive transcranial magnetic stimulation (rTMS) in chronic pain according to different pain syndromes and stimulation parameters. DATA SOURCES: Publications on rTMS and chronic pain were searched in PubMed and Google Scholar using the following key words: chronic pain, analgesia, transcranial magnetic stimulation, neuropathic pain, fibromyalgia, and complex regional pain syndrome. STUDY SELECTION: This review only included double-blind, controlled studies with >10 participants in each arm that were published from 1996 to 2014 and written in English. Studies with relevant information for the understanding of the effects of rTMS were also cited. DATA EXTRACTION: The following data were retained: type of pain syndrome, type of study, coil type, target, stimulation intensity, frequency, number of pulses, orientation of induced current, number of session, and a brief summary of intervention outcomes. DATA SYNTHESIS: A total of 33 randomized trials were found. Many studies reported significant pain relief by rTMS, especially high-frequency stimulation over the primary motor cortex performed in consecutive treatment sessions. Pain relief was frequently >30% compared with control treatment. Neuropathic pain, fibromyalgia, and complex regional pain syndrome were the pain syndromes more frequently studied. However, among all published studies, only a few performed repetitive sessions of rTMS. CONCLUSIONS: rTMS has potential utility in the management of chronic pain; however, studies using maintenance sessions of rTMS and assessing the effects of rTMS on the different aspects of chronic pain are needed to provide a more solid basis for its clinical application for pain relief.


Subject(s)
Chronic Pain/rehabilitation , Transcranial Magnetic Stimulation/methods , Complex Regional Pain Syndromes/rehabilitation , Fibromyalgia/rehabilitation , Humans , Motor Cortex , Neuralgia/rehabilitation , Physical Therapy Modalities
6.
Neurology ; 83(16): 1403-9, 2014 Oct 14.
Article in English | MEDLINE | ID: mdl-25217059

ABSTRACT

OBJECTIVE: To prospectively evaluate the effect of subthalamic nucleus deep brain stimulation (STN-DBS) on the different characteristics of pain and other nonmotor symptoms (NMS) in patients with Parkinson disease (PD). METHODS: Forty-four patients with PD and refractory motor symptoms were screened for STN-DBS. Patients were evaluated before and 1 year after surgery. The primary outcome was change in pain prevalence after surgery. Secondary outcome measures were changes in motor function (Unified Parkinson's Disease Rating Scale), characteristics of pain and other NMS using specific scales and questionnaires, and quality of life. RESULTS: Forty-one patients completed the study. The prevalence of pain changed from 70% to 21% after surgery (p < 0.001). There were also significant improvements in pain intensity, NMS, and quality of life after STN-DBS (p < 0.05). Dystonic and musculoskeletal pain responded well to DBS, while central pain and neuropathic pain were not influenced by surgery. There was a strong correlation between the change in pain intensity and the improvement in quality of life (r = 0.708, p < 0.005). No correlation was found between pain improvement and preoperative response to levodopa or motor improvement during stimulation (r = 0.247, p = 0.197 and r = 0.249, p = 0.193, respectively) or with changes in other NMS. CONCLUSIONS: STN-DBS decreased pain after surgery, but had different effects in different types of PD-related pain. Motor and nonmotor symptom improvements after STN-DBS did not correlate with pain relief. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that in patients with idiopathic PD with refractory motor fluctuations, STN-DBS decreases the prevalence of pain and improves quality of life.


Subject(s)
Deep Brain Stimulation , Pain Management/methods , Pain/physiopathology , Parkinson Disease/physiopathology , Parkinson Disease/therapy , Female , Humans , Male , Middle Aged , Motor Activity , Pain/epidemiology , Pain Measurement , Parkinson Disease/epidemiology , Parkinson Disease/psychology , Prevalence , Prospective Studies , Quality of Life , Regression Analysis , Severity of Illness Index , Treatment Outcome
7.
Clin EEG Neurosci ; 43(4): 285-90, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23185088

ABSTRACT

The objective of this study was to perform a systematic review regarding the effects of transcranial magnetic stimulation (TMS) on the cognitive event-related potential P300. A search was performed of the PubMed database, using the keywords "transcranial magnetic stimulation" and "P300." Eight articles were selected and, after analysis of references, one additional article was added to the list. We found the comparison among studies to be difficult, as the information regarding the effects of TMS on P300 is both scarce and heterogeneous with respect to the parameters used in TMS stimulation and the elicitation of P300. However, 7 of 9 studies found positive results. New studies need to be carried out in order to understand the contribution of these variables and others to the alteration in the latency and amplitude of the P300 wave.


Subject(s)
Brain/physiology , Cognition/physiology , Event-Related Potentials, P300/physiology , Transcranial Magnetic Stimulation/methods , Humans
8.
Neuropsychiatr Dis Treat ; 8: 197-201, 2012.
Article in English | MEDLINE | ID: mdl-22665996

ABSTRACT

UNLABELLED: Transcranial magnetic stimulation (TMS) is a promising method for both investigation and therapeutic treatment of psychiatric and neurologic disorders and, more recently, for brain mapping. This study describes the application of navigated TMS for motor cortex mapping in patients with a brain tumor located close to the precentral gyrus. MATERIALS AND METHODS: In this prospective study, six patients with low-grade gliomas in or near the precentral gyrus underwent TMS, and their motor responses were correlated to locations in the cortex around the lesion, generating a functional map overlaid on three-dimensional magnetic resonance imaging (MRI) scans of the brain. To determine the accuracy of this new method, we compared TMS mapping with the gold standard mapping with direct cortical electrical stimulation in surgery. The same navigation system and TMS-generated map were used during the surgical resection procedure. RESULTS: The motor cortex could be clearly mapped using both methods. The locations corresponding to the hand and forearm, found during intraoperative mapping, showed a close spatial relationship to the homotopic areas identified by TMS mapping. The mean distance between TMS and direct cortical electrical stimulation (DES) was 4.16 ± 1.02 mm (range: 2.56-5.27 mm). CONCLUSION: Preoperative mapping of the motor cortex with navigated TMS prior to brain tumor resection is a useful presurgical planning tool with good accuracy.

9.
Brain Stimul ; 2(1): 14-21, 2009 Jan.
Article in English | MEDLINE | ID: mdl-20633399

ABSTRACT

Brain imaging studies performed over the past 20 years have generated new knowledge about the specific brain regions involved in the brain diseases that have been classically labeled as psychiatric. These include the mood and anxiety disorders, and the schizophrenias. As a natural next step, clinical researchers have investigated whether the minimally invasive brain stimulation technologies (transcranial magnetic stimulation [TMS] or transcranial direct current stimulation [tDCS]) might potentially treat these disorders. In this review, we critically review the research studies that have examined TMS or tDCS as putative treatments for depression, mania, obsessive-complusive disorder, posttraumatic stress disorder, panic disorder, or schizophrenia. (Separate controversy articles deal with using TMS or tDCS to treat pain or tinnitus. We will not review here the large number of studies using TMS or tDCS as research probes to understand disease mechanisms of psychiatric disorders.) Although there is an extensive body of randomized controlled trials showing antidepressant effects of daily prefrontal repetitive TMS, the magnitude or durability of this effect remains controversial. US Food and Drug Administration approval of TMS for depression was recently granted. There is much less data in all other diseases, and therapeutic effects in other psychiatric conditions, if any, are still controversial. Several issues and problems extend across all psychiatric TMS studies, including the optimal method for a sham control, appropriate coil location, best device parameters (intensity, frequency, dosage, and dosing schedule) and refining what subjects should be doing during treatment (activating pathologic circuits or not). In general, TMS or tDCS as a treatment for most psychiatric disorders remains exciting but controversial, other than prefrontal TMS for depression.


Subject(s)
Anxiety Disorders/therapy , Bipolar Disorder/therapy , Depressive Disorder/therapy , Schizophrenia/therapy , Transcranial Magnetic Stimulation/methods , Transcutaneous Electric Nerve Stimulation/methods , Clinical Trials as Topic , Device Approval , Humans
10.
J Clin Psychiatry ; 68(10): 1528-32, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17960967

ABSTRACT

OBJECTIVE: To study the therapeutic effects on auditory hallucinations refractory to clozapine with 1-Hz repetitive transcranial magnetic stimulation (rTMS) applied on the left temporoparietal cortex. METHOD: Eleven patients with schizophrenia (DSM-IV) experiencing auditory hallucinations (unresponsive to clozapine) were randomly assigned to receive either active of rTMS (N = 6) or sham stimulation (N = 5) (with concomitant use of clozapine) using a double-masked, sham-controlled, parallel design. A total of 160 minutes of rTMS (9600 pulses) was administered over 10 days at 90% motor threshold. The study was conducted from January 2003 to December 2005. RESULTS: There was a reduction in hallucination scores in both groups, which persisted during follow-up in the active group for the items reality (p = .0493) and attentional salience (p = .0360). Both groups showed similar patterns of symptomatic changes on subscales (negative symptoms, general psychopathology) and total scores of the Positive and Negative Syndrome Scale, Clinical Global Impressions scale, and Visual Analog Scale. CONCLUSION: Active rTMS in association with clozapine can be administered safely to treat auditory hallucinations, although its clinical utility is still questionable. No significant clinical effects were observed in the sample studied, possibly because it was too small and/or due to its high refractoriness.


Subject(s)
Clozapine/therapeutic use , Drug Resistance , Hallucinations/drug therapy , Hallucinations/etiology , Schizophrenia/diagnosis , Schizophrenia/therapy , Schizophrenic Psychology , Transcranial Magnetic Stimulation/methods , Adult , Demography , Diagnostic and Statistical Manual of Mental Disorders , Double-Blind Method , Female , Hallucinations/epidemiology , Humans , Male , Severity of Illness Index , Treatment Outcome
11.
J ECT ; 23(1): 6-8, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17435563

ABSTRACT

Cardiovascular alterations during electroconvulsive therapy (ECT) are a major concern for this treatment. Although several studies have been performed to compare the effects of anesthetics on these alterations, the results are mixed and doubt still exists regarding the choice of the best drug. We conducted a randomized, double-blind clinical trial to compare the effects of 3 anesthetics used in ECT: etomidate, propofol, and thiopental. Patients (N=30) were randomized to receive one of these drugs as the anesthetic for the ECT procedure. Cardiovascular evaluation consisted of the measurement of blood systolic and diastolic pressure and heart rate before and immediately after the end of the seizure for each patient during a course of ECT. The results showed that etomidate, propofol, and thiopental were associated with similar cardiovascular effects.


Subject(s)
Anesthetics, Intravenous/administration & dosage , Cardiovascular System/drug effects , Depressive Disorder, Major/therapy , Electroconvulsive Therapy , Etomidate/administration & dosage , Propofol/administration & dosage , Thiopental/administration & dosage , Adult , Anesthesia, Intravenous , Anesthetics, Intravenous/adverse effects , Dose-Response Relationship, Drug , Double-Blind Method , Etomidate/adverse effects , Female , Humans , Logistic Models , Male , Middle Aged , Propofol/adverse effects , Thiopental/adverse effects , Treatment Outcome
12.
J ECT ; 22(4): 237-9, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17143152

ABSTRACT

The use of right unilateral electrode placement for electroconvulsive therapy (ECT) is one of the most important developments on the technique because it is considered to spare cognition. Nevertheless, the best way to determine the charge to be given to the individual patient is still controversial. We present an open study on the use of right unilateral ECT using the technique of method of limits and giving treatments with 6 times the seizure threshold. Of 30 patients, there was a response/remission rate of 53.33%, as measured by the Hamilton Depression Rating Scale, after a mean of 8 sessions. Half of the nonresponders (n = 7) received subsequent bilateral ECT, with improvement on 4. The data suggest that it is a good practice to start the treatment with unilateral ECT and, if no response is achieved, to switch to bilateral placement.


Subject(s)
Depressive Disorder, Major/therapy , Electric Stimulation Therapy , Electroconvulsive Therapy/methods , Adult , Anesthetics/therapeutic use , Electroconvulsive Therapy/standards , Electrodes/standards , Female , Functional Laterality , Humans , Male , Titrimetry , Treatment Outcome
13.
J ECT ; 22(4): 265-6, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17143158

ABSTRACT

Accidental induction of convulsions by using repetitive transcranial magnetic stimulation (rTMS) has been reported to have occurred in 6 normal voluntary subjects, in 1 patient with depression and in 1 patient who had temporal lobe epilepsy, with secondary generalization. In addition, 3 other cases have been published relating its use with seizure induction and in 1 case, using 1-Hz stimulation. In this paper, we report a patient who was participating in a protocol for the use of rTMS in chronic pain, with stimulation in the motor cortex, who developed a generalized seizure in the fifth application. Intertrain interval was within safety guidelines, but the combination of 10 Hz for 10 seconds was excessive and must be considered the main cause for the episode. No further complication has been noted after she was withdrawn from the study protocol.


Subject(s)
Motor Cortex/physiopathology , Seizures/etiology , Transcranial Magnetic Stimulation/adverse effects , Adult , Female , Humans , Seizures/physiopathology
14.
Int J Neuropsychopharmacol ; 9(6): 641-54, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16939662

ABSTRACT

Although previous clinical trials have suggested that repetitive transcranial magnetic stimulation (rTMS) has a significant antidepressant effect, the results of these trials are heterogeneous. We hypothesized that individual patients' characteristics might contribute to such heterogeneity. Our aim was to identify predictors of antidepressant response to rTMS. We pooled data from six separate clinical trials conducted independently, which evaluated the effects of rapid rTMS of the left dorsolateral prefrontal cortex in patients with major depression. We investigated 195 patients with regard to demographic, depression and treatment characteristics, psychiatric and drug history. Results showed that age and treatment refractoriness were significant negative predictors of depression improvement when adjusting these variables to other significant predictors and confounders. These findings were not confounded by methodological differences from the six studies, as the results were adjusted for the study site. In conclusion TMS antidepressant therapy in younger and less treatment-resistant patients is associated with better outcome.


Subject(s)
Depressive Disorder, Major/therapy , Transcranial Magnetic Stimulation , Adolescent , Adult , Aged , Aged, 80 and over , Aging/psychology , Antidepressive Agents/therapeutic use , Depressive Disorder, Major/psychology , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Psychiatric Status Rating Scales , Randomized Controlled Trials as Topic , Treatment Outcome
15.
Clin Neurophysiol ; 117(6): 1217-27, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16644277

ABSTRACT

OBJECTIVE: The preliminary results of noninvasive brain stimulation for epilepsy treatment have been encouraging, but mixed. Two important factors may contribute to this heterogeneity: the altered brain physiology of patients with epilepsy and the variable presence of antiepileptic drugs. Therefore, we aimed to study the effects of 1 Hz rTMS on corticospinal excitability in patients with juvenile myoclonic epilepsy (JME) in two different conditions: low- or high-plasma valproate levels. METHODS: Fifteen patients with JME and 12 age-matched healthy subjects participated in this study. Corticospinal excitability before and after 1 Hz rTMS was assessed in JME patients with low- and high-plasma valproate levels; and these results were compared with those in healthy subjects. RESULTS: In patients with chronic use of valproate and low-plasma concentrations, 1 Hz rTMS had a similar significant inhibitory effect on corticospinal excitability as in healthy subjects. However, in the same patients when the serum valproate concentration was high, 1 Hz rTMS increased the corticospinal excitability significantly. In addition, there was a significant positive correlation between plasma valproate levels and the motor threshold changes after 1 Hz rTMS. CONCLUSIONS: Our findings can be accounted for by mechanisms of homeostatic plasticity and illustrate the dependency of the modulatory effects of rTMS on the physiologic state of the targeted brain cortex. SIGNIFICANCE: The therapeutic use of rTMS in epilepsy should take into consideration the interaction between rTMS and drugs that change cortical excitability.


Subject(s)
Anticonvulsants/blood , Myoclonic Epilepsy, Juvenile/drug therapy , Pyramidal Tracts/drug effects , Transcranial Magnetic Stimulation , Valproic Acid/blood , Adolescent , Adult , Anticonvulsants/administration & dosage , Combined Modality Therapy , Homeostasis/drug effects , Humans , Myoclonic Epilepsy, Juvenile/physiopathology , Pyramidal Tracts/physiopathology , Treatment Outcome , Valproic Acid/administration & dosage
17.
Psychiatry Res ; 141(1): 1-13, 2006 Jan 30.
Article in English | MEDLINE | ID: mdl-16352348

ABSTRACT

Repetitive transcranial magnetic stimulation (rTMS) holds promise as a therapeutic tool in major depression. However, a means to assess the effects of a single rTMS session on mood to guide subsequent sessions would be desirable. The present study examined the effects of a single rTMS session on an affective go/no-go task known to measure emotional-cognitive deficits associated with major depression. Ten patients with an acute episode of unipolar major depression and eight partially or completely remitted (improved) patients underwent 1 Hz rTMS over the left and right dorsolateral prefrontal cortex prior to task performance. TMS over the mesial occipital cortex was used as a control. We observed significantly improved performance in depressed patients following right prefrontal rTMS. This beneficial effect declined with decreasing depression severity and tended to reverse in the improved group. Left prefrontal rTMS had no significant effect in the depressed group, but it resulted in impaired task performance in the improved group. Our findings indicate that the acute response of depressed patients to rTMS varies with the stimulation site and depression severity. Further studies are needed to determine whether the present paradigm could be used to predict antidepressant treatment success or to individualize stimulation parameters according to specific pathology.


Subject(s)
Brain/physiology , Depressive Disorder, Major/therapy , Transcranial Magnetic Stimulation/methods , Antidepressive Agents/therapeutic use , Cognition Disorders/epidemiology , Depressive Disorder, Major/diagnosis , Depressive Disorder, Major/drug therapy , Female , Functional Laterality/physiology , Humans , Male , Middle Aged , Occipital Lobe/physiology , Photic Stimulation/methods , Prefrontal Cortex/physiology , Severity of Illness Index , Treatment Outcome
18.
Neuroreport ; 16(14): 1551-5, 2005 Sep 28.
Article in English | MEDLINE | ID: mdl-16148743

ABSTRACT

Recovery of function after a stroke is determined by a balance of activity in the neural network involving both the affected and the unaffected brain hemispheres. Increased activity in the affected hemisphere can promote recovery, while excessive activity in the unaffected hemisphere may represent a maladaptive strategy. We therefore investigated whether reduction of the excitability in the unaffected hemisphere by cathodal transcranial direct current stimulation could result in motor performance improvement in stroke patients. We compared these results with excitability-enhancing anodal transcranial direct current stimulation of the affected hemisphere and sham transcranial direct current stimulation. Both cathodal stimulation of the unaffected hemisphere and anodal stimulation of the affected hemisphere (but not sham transcranial direct current stimulation) improved motor performance significantly. These results suggest that the appropriate modulation of bihemispheric brain structures can promote motor function recovery.


Subject(s)
Deep Brain Stimulation , Functional Laterality/radiation effects , Psychomotor Performance/radiation effects , Stroke/therapy , Aged , Analysis of Variance , Demography , Electrodes , Female , Humans , Male , Middle Aged , Stroke/physiopathology , Time Factors
19.
Exp Brain Res ; 166(1): 23-30, 2005 Sep.
Article in English | MEDLINE | ID: mdl-15999258

ABSTRACT

Previous studies have claimed that weak transcranial direct current stimulation (tDCS) induces persisting excitability changes in the human motor cortex that can be more pronounced than cortical modulation induced by transcranial magnetic stimulation, but there are no studies that have evaluated the effects of tDCS on working memory. Our aim was to determine whether anodal transcranial direct current stimulation, which enhances brain cortical excitability and activity, would modify performance in a sequential-letter working memory task when administered to the dorsolateral prefrontal cortex (DLPFC). Fifteen subjects underwent a three-back working memory task based on letters. This task was performed during sham and anodal stimulation applied over the left DLPFC. Moreover seven of these subjects performed the same task, but with inverse polarity (cathodal stimulation of the left DLPFC) and anodal stimulation of the primary motor cortex (M1). Our results indicate that only anodal stimulation of the left prefrontal cortex, but not cathodal stimulation of left DLPFC or anodal stimulation of M1, increases the accuracy of the task performance when compared to sham stimulation of the same area. This accuracy enhancement during active stimulation cannot be accounted for by slowed responses, as response times were not changed by stimulation. Our results indicate that left prefrontal anodal stimulation leads to an enhancement of working memory performance. Furthermore, this effect depends on the stimulation polarity and is specific to the site of stimulation. This result may be helpful to develop future interventions aiming at clinical benefits.


Subject(s)
Electric Stimulation Therapy/methods , Memory, Short-Term/physiology , Prefrontal Cortex/physiology , Adult , Electrodes/standards , Female , Humans , Male , Memory Disorders/therapy , Motor Cortex/physiology , Neuropsychological Tests
20.
Mov Disord ; 20(9): 1178-84, 2005 Sep.
Article in English | MEDLINE | ID: mdl-15895421

ABSTRACT

Previous studies show that cognitive functions are more impaired in patients with Parkinson's disease (PD) and depression than in nondepressed PD patients. We compared the cognitive effects of two types of antidepressant treatments in PD patients: fluoxetine (20 mg/day) versus repetitive transcranial magnetic stimulation (rTMS, 15 Hz, 110% above motor threshold, 10 daily sessions) of the left dorsolateral prefrontal cortex. Twenty-five patients with PD and depression were randomly assigned either to Group 1 (active rTMS and placebo medication) or to Group 2 (sham rTMS and fluoxetine). A neuropsychological battery was assessed by a rater blind to treatment arm at baseline and 2 and 8 weeks after treatment. Patients in both groups had a significant improvement of Stroop (colored words and interference card) and Hooper and Wisconsin (perseverative errors) test performances after both treatments. Furthermore, there were no adverse effects after either rTMS or fluoxetine in any neuropsychological test of the cognitive test battery. The results show that rTMS could improve some aspects of cognition in PD patients similar to that of fluoxetine. The mechanisms for this cognitive improvement are unclear, but it is in the context of mood improvement.


Subject(s)
Cognition Disorders/diagnosis , Cognition Disorders/epidemiology , Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/epidemiology , Fluoxetine/therapeutic use , Parkinson Disease/epidemiology , Periodicity , Selective Serotonin Reuptake Inhibitors/therapeutic use , Transcranial Magnetic Stimulation/instrumentation , Aged , Antiparkinson Agents/therapeutic use , Double-Blind Method , Female , Functional Laterality/physiology , Humans , Levodopa/therapeutic use , Male , Neuropsychological Tests , Parkinson Disease/drug therapy , Parkinson Disease/physiopathology , Prefrontal Cortex/physiopathology , Severity of Illness Index
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