The Experts below are selected from a list of 28467 Experts worldwide ranked by ideXlab platform
Flavio Frohlich - One of the best experts on this subject based on the ideXlab platform.
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randomized trial of transcranial alternating current stimulation for treatment of auditory Hallucinations in schizophrenia
European Psychiatry, 2018Co-Authors: Juliann M Mellin, Sankaraleengam Alagapan, Caroline Lustenberger, Courtney E Lugo, Morgan L Alexander, John H Gilmore, Fredrik L Jarskog, Flavio FrohlichAbstract:Abstract Background Approximately 30% of patients with schizophrenia experience auditory Hallucinations that are refractory to antipsychotic medications. Here, we evaluated the feasibility and efficacy of transcranial alternating current stimulation (tACS) that we hypothesized would improve auditory hallucination symptoms by enhancing synchronization between the frontal and temporo-parietal areas of the left hemisphere. Method 22 participants were randomized to one of three arms and received twice daily, 20 min sessions of sham, 10 Hz 2 mA peak-to-peak tACS, or 2 mA tDCS over the course of 5 consecutive days. Symptom improvement was assessed using the Auditory Hallucination Rating Scale (AHRS) as the primary outcome measure. The Positive and Negative Syndrome Scale (PANSS) and the Brief Assessment of Cognition in Schizophrenia (BACS) were secondary outcomes. Results Primary and secondary behavioral outcomes were not significantly different between the three arms. However, effect size analyses show that tACS had the greatest effect based on the auditory Hallucinations scale for the week of stimulation (1.31 for tACS; 1.06 and 0.17, for sham and tDCS, respectively). Effect size analysis for the secondary outcomes revealed heterogeneous results across measures and stimulation conditions. Conclusions To our knowledge, this is the first clinical trial of tACS for the treatment of symptoms of a psychiatric condition. Further studies with larger sample sizes are needed to better understand the effect of tACS on auditory Hallucinations.
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exploratory study of once daily transcranial direct current stimulation tdcs as a treatment for auditory Hallucinations in schizophrenia
European Psychiatry, 2016Co-Authors: Flavio Frohlich, Juliann M Mellin, Caroline Lustenberger, John H Gilmore, T N Burrello, A L Cordle, L F JarskogAbstract:Abstract Background Auditory Hallucinations are resistant to pharmacotherapy in about 25% of adults with schizophrenia. Treatment with noninvasive brain stimulation would provide a welcomed additional tool for the clinical management of auditory Hallucinations. A recent study found a significant reduction in auditory Hallucinations in people with schizophrenia after five days of twice-daily transcranial direct current stimulation (tDCS) that simultaneously targeted left dorsolateral prefrontal cortex and left temporo-parietal cortex. Hypothesis We hypothesized that once-daily tDCS with stimulation electrodes over left frontal and temporo-parietal areas reduces auditory Hallucinations in patients with schizophrenia. Methods We performed a randomized, double-blind, sham-controlled study that evaluated five days of daily tDCS of the same cortical targets in 26 outpatients with schizophrenia and schizoaffective disorder with auditory Hallucinations. Results We found a significant reduction in auditory Hallucinations measured by the Auditory Hallucination Rating Scale (F 2,50 =12.22, P 2,48 =0.43, P =0.65). No significant change of overall schizophrenia symptom severity measured by the Positive and Negative Syndrome Scale was observed. Conclusions The lack of efficacy of tDCS for treatment of auditory Hallucinations and the pronounced response in the sham-treated group in this study contrasts with the previous finding and demonstrates the need for further optimization and evaluation of noninvasive brain stimulation strategies. In particular, higher cumulative doses and higher treatment frequencies of tDCS together with strategies to reduce placebo responses should be investigated. Additionally, consideration of more targeted stimulation to engage specific deficits in temporal organization of brain activity in patients with auditory Hallucinations may be warranted.
John H Krystal - One of the best experts on this subject based on the ideXlab platform.
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probing the pathophysiology of auditory verbal Hallucinations by combining functional magnetic resonance imaging and transcranial magnetic stimulation
Cerebral Cortex, 2007Co-Authors: Ralph E Hoffman, Keith A Hawkins, Michelle Hampson, Kun Wu, Adam W Anderson, John C Gore, Robert J Buchanan, Todd R Constable, Neayka Sahay, John H KrystalAbstract:Functional magnetic resonance imaging and repetitive transcranial magnetic stimulation (rTMS) were used to explore the pathophysiology of auditory/verbal Hallucinations (AVHs). Sixteen patients with schizophrenia-spectrum disorder were studied with continuous or near continuous AVHs. For patients with intermittent Hallucinations (N = 8), blood oxygenation level-dependent (BOLD) activation maps comparing hallucination and nonhallucination periods were generated. For patients with continuous Hallucinations (N = 8) correlations between BOLD signal time course in Wernicke’s area, and other regions were used to map functional coupling to the former. These maps were used to identify 3–6 cortical sites per patient that were probed with 1-Hz rTMS and sham stimulation. Delivering rTMS to left temporoparietal sites in Wernicke’s area and the adjacent supramarginal gyrus was accompanied by a greater rate of AVH improvement compared with sham stimulation and rTMS delivered to anterior temporal sites. For intermittent hallucinators, lower levels of hallucination-related activation in Broca’s area strongly predicted greater rate of response to left temporoparietal rTMS. For continuous hallucinators, reduced coupling between Wernicke’s and a right homologue of Broca’s area strongly predicted greater left temporoparietal rTMS rate of response. These findings suggest that dominant hemisphere temporoparietal areas are involved in expressing AVHs, with higher levels of coactivation and/or coupling involving inferior frontal regions reinforcing underlying pathophysiology.
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temporoparietal transcranial magnetic stimulation for auditory Hallucinations safety efficacy and moderators in a fifty patient sample
Biological Psychiatry, 2005Co-Authors: Ralph E Hoffman, Ralitza Gueorguieva, Keith A Hawkins, Maxine Varanko, Nash N Boutros, Yute Wu, Kathleen M Carroll, John H KrystalAbstract:Background Auditory Hallucinations are often resistant to treatment and can produce significant distress and behavioral difficulties. A preliminary report based on 24 patients with schizophrenia or schizoaffective disorder indicated greater improvement in auditory Hallucinations following 1-hertz left temporoparietal repetitive transcranial magnetic stimulation (rTMS) compared to sham stimulation. Data from the full 50-subject sample incorporating 26 new patients are now presented to more comprehensively assess safety/tolerability, efficacy and moderators of this intervention. Methods Right-handed patients experiencing auditory Hallucinations at least 5 times per day were randomly allocated to receive either rTMS or sham stimulation. A total of 132 minutes of rTMS was administered over 9 days at 90% motor threshold using a double-masked, sham-controlled, parallel design. Results Hallucination Change Score was more improved for rTMS relative to sham stimulation ( p = .008) as was the Clinical Global Impressions Scale ( p = .0004). Hallucination frequency was significantly decreased during rTMS relative to sham stimulation ( p = .0014) and was a moderator of rTMS effects ( p = .008). There was no evidence of neurocognitive impairment associated with rTMS. Conclusions Left temporoparietal 1-hertz rTMS warrants further study as an intervention for auditory Hallucinations. Data suggest that this intervention selectively alters neurobiological factors determining frequency of these Hallucinations.
André Aleman - One of the best experts on this subject based on the ideXlab platform.
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report on the inaugural meeting of the international consortium on hallucination research a clinical and research update and 16 consensus set goals for future research
Schizophrenia Bulletin, 2012Co-Authors: Flavie Waters, André Aleman, Charles Fernyhough, Paul AllenAbstract:This article presents a report on the first meeting of the International Consortium on Hallucination Research, which took place on September 13-14, 2011 at the Institute of Psychiatry, London. The first day of the meeting served to reflect on the current state of knowledge regarding auditory Hallucinations in different diagnostic groups, based on the presentations from the phenomenology, cognition, emotion, electrophysiology, neurochemical, neuroimaging, genetics, treatment, and computational modeling working groups. The second day comprised a discussion forum where the most important and urgent questions for future research were identified. The meeting recognized that a lot has been achieved in auditory hallucination research but that much still remains to be done. Here, we outline the top 16 goals for research on auditory Hallucinations, which cover topics of conceptual importance, academic and treatment issues, scientific rigor, and cross-disciplinary collaboration. Concerted and coordinated actions will be required to make substantial research progress.
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effects of bilateral repetitive transcranial magnetic stimulation on treatment resistant auditory verbal Hallucinations in schizophrenia a randomized controlled trial
Schizophrenia Research, 2009Co-Authors: Ans Vercammen, Henderikus Knegtering, Richard Bruggeman, Hanneke M Westenbroek, J A Jenner, C J Slooff, Lex Wunderink, André AlemanAbstract:Abstract Background Neuroimaging findings implicate bilateral superior temporal regions in the genesis of auditory–verbal Hallucinations (AVH). This study aimed to investigate whether 1 Hz repetitive transcranial magnetic stimulation (rTMS) of the bilateral temporo-parietal region would lead to increased effectiveness in the management of AVH, compared to left rTMS or placebo. Methods 38 patients with schizophrenia (DSM-IV) and medication-resistant AVH were randomly assigned to 1 Hz rTMS treatment of the left temporo-parietal region, bilateral temporo-parietal regions, or placebo. Stimulation was conducted over 6 days, twice daily for 20 min, at 90% of the motor threshold. Effect measures included the Auditory Hallucination Rating Scale (AHRS), Positive and Negative Affect Scale (PANAS), and a score for hallucination severity obtained from the Positive and Negative Syndrome Scale (PANSS). Results All groups showed some improvement on the total AHRS. Hallucination frequency was significantly reduced in the left rTMS group only. The bilateral rTMS group demonstrated the most remarkable reduction in self-reported affective responsiveness to AVH. A modest, but significant decrease on the PANSS hallucination item was observed in the combined rTMS treatment group, whereas no change occurred in the placebo group. The left rTMS group showed a significant reduction on the general psychopathology subscale. Conclusion Compared to bilateral or sham stimulation, rTMS of the left temporo-parietal region appears most effective in reducing auditory Hallucinations, and additionally may have an effect on general psychopathology. Placebo effects should however not be ruled out, since sham stimulation also led to improvement on a number of AVH parameters.
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cognitive basis of Hallucinations in schizophrenia role of top down information processing
Schizophrenia Research, 2003Co-Authors: André Aleman, K B E Bocker, Ron Hijman, Edward H F De Haan, Rene S KahnAbstract:Hallucinations in schizophrenia have been regarded to result from the erroneous attribution of internally generated information to an external source. Distortions in mental imagery may underlie such confusions. We investigated performance of 77 subjects on multiple behavioral measures of auditory and visual mental imagery and perception, and a measure of reality monitoring. Comparisons were made between performance of schizophrenia patients with (N=22) and without (N=35) Hallucinations and matched normal comparison subjects (N=20), after controlling for attentional factors. No differences emerged on any of the mental imagery measures, nor on reality monitoring accuracy. This suggests that there is no stable disposition towards abnormal mental imagery associated with Hallucinations. However, for patients with active Hallucinations (N=12), hallucination severity correlated positively with a measure of imagery-perception interaction in the auditory modality, r=0.70, p=0.01. Although preliminary, this finding is consistent with recent theoretical proposals in which Hallucinations have been suggested to result from an increased influence of top-down sensory expectations on conscious perception.
Vikas Menon - One of the best experts on this subject based on the ideXlab platform.
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repetitive transcranial magnetic stimulation in persistent auditory hallucination in schizophrenia predictors of response
Current Behavioral Neuroscience Reports, 2020Co-Authors: Sujita Kumar Kar, Vikas MenonAbstract:This review aims to discuss the role of repetitive Transcranial Magnetic Stimulation (rTMS) in schizophrenia for the management of persistent auditory hallucination, along with the predictors of response. Schizophrenia is a chronic, highly disabling, severe mental illness. Antipsychotic medications are the mainstay of treatment in schizophrenia. Despite adequate pharmacotherapy, a considerable number of patients remain symptomatic, for which brain stimulation (neuromodulation) techniques like electroconvulsive therapy, repetitive transcranial magnetic stimulation and transcranial direct current stimulation are being increasingly used. Persistent auditory hallucination resistant to pharmacotherapy (antipsychotic treatment) is a therapeutic challenge. It is found to be due to abnormal hyperactivity of the neurons at the temporo-parietal junction of dominant hemisphere. Commonly, low-frequency repetitive transcranial magnetic stimulation has been used in the treatment of medication-resistant auditory hallucination. Various factors predict the response to repetitive transcranial magnetic stimulation in the management of resistant auditory hallucination. Identification of various predictors will guide clinicians in the appropriate selection of rTMS to target auditory Hallucinations in schizophrenia.
L F Jarskog - One of the best experts on this subject based on the ideXlab platform.
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exploratory study of once daily transcranial direct current stimulation tdcs as a treatment for auditory Hallucinations in schizophrenia
European Psychiatry, 2016Co-Authors: Flavio Frohlich, Juliann M Mellin, Caroline Lustenberger, John H Gilmore, T N Burrello, A L Cordle, L F JarskogAbstract:Abstract Background Auditory Hallucinations are resistant to pharmacotherapy in about 25% of adults with schizophrenia. Treatment with noninvasive brain stimulation would provide a welcomed additional tool for the clinical management of auditory Hallucinations. A recent study found a significant reduction in auditory Hallucinations in people with schizophrenia after five days of twice-daily transcranial direct current stimulation (tDCS) that simultaneously targeted left dorsolateral prefrontal cortex and left temporo-parietal cortex. Hypothesis We hypothesized that once-daily tDCS with stimulation electrodes over left frontal and temporo-parietal areas reduces auditory Hallucinations in patients with schizophrenia. Methods We performed a randomized, double-blind, sham-controlled study that evaluated five days of daily tDCS of the same cortical targets in 26 outpatients with schizophrenia and schizoaffective disorder with auditory Hallucinations. Results We found a significant reduction in auditory Hallucinations measured by the Auditory Hallucination Rating Scale (F 2,50 =12.22, P 2,48 =0.43, P =0.65). No significant change of overall schizophrenia symptom severity measured by the Positive and Negative Syndrome Scale was observed. Conclusions The lack of efficacy of tDCS for treatment of auditory Hallucinations and the pronounced response in the sham-treated group in this study contrasts with the previous finding and demonstrates the need for further optimization and evaluation of noninvasive brain stimulation strategies. In particular, higher cumulative doses and higher treatment frequencies of tDCS together with strategies to reduce placebo responses should be investigated. Additionally, consideration of more targeted stimulation to engage specific deficits in temporal organization of brain activity in patients with auditory Hallucinations may be warranted.
