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BACKGROUND: The purpose of this study was to investigate the long-term efficacy of transcranial direct current stimulation (tDCS) in the neurorehabilitation of Alzheimer's disease (AD). METHODS: Thirty-four AD patients were randomly assigned to three groups: anodal, cathodal, and sham tDCS. Stimulation was applied over the left dorsolateral prefrontal cortex for 25 min at 2 mA, daily for 10 days. Each patient was submitted to the following psychometric assessments: mini-mental state examination (MMSE) and Wechsler adult intelligence scale-third edition at base line, at the end of the 10th sessions and then at 1 and 2 months after the end of the sessions. Motor cortical excitability and the P300 event-related potential were assessed at baseline and after the last tDCS session. RESULTS: Significant treatment group × time interactions were observed for the MMSE and performance IQ of the WAIS. Post hoc comparisons showed that both anodal and cathodal tDCS (ctDCS) improved MMSE in contrast to sham tDCS. Whereas, this was only true for ctDCS in the performance IQ. Remarkably, tDCS also reduced the P300 latency, but had no effect on motor cortex excitability. CONCLUSION: Our findings reveal that repeated sessions of tDCS could not only improve cognitive function but also reduce the P300 latency, which is known to be pathologically increased in AD.

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BACKGROUND: Existing treatments for adults with anorexia nervosa (AN) have limited proven efficacy. New treatments that have been suggested involve targeted, brain-directed interventions such as transcranial direct current stimulation (tDCS). We describe findings from seven individuals with treatment-resistant AN who received 10 sessions of anodal tDCS, over the left dorsolateral prefrontal cortex (DLPFC). MATERIAL AND METHOD: In this open-label, single-arm study, seven patients received anodal tDCS (2mA) for 25 minutes over the left dorsolateral prefrontal cortex daily for ten days. Assessments pre-tDCS, post-tDCS and one month later included the Eating Attitude Test (EAT), Eating Disorder Inventory (EDI) and Beck Depression Inventory (BDI). RESULTS: Three patients improved in all three rating scales immediately after the treatment sessions and one month later. Two patients showed improvement at the end of treatment but returned to the baseline after one month. One subject improved only on the BDI scale but not eating scales. The scores in the three rating scales were unaffected by treatment in the remaining patient. There was a significant effect of time (pre, post and 1 month later) on the three rating scores; BDI (P = 0.016), EDI (P = 0.018) and EAT (P = 0.016) and a significant correlation between the percent improvement of BDI and EAT (p = 0.01), and between BDI and EDI (P = 0.006). CONCLUSIONS: These findings suggest that tDCS has potential as an adjuvant treatment for AN and deserves further study.

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BACKGROUND: Recent neuroimaging studies on poststroke aphasia revealed maladaptive cortical changes in both hemispheres, yet their functional contribution in language recovery remains elusive. The aim of this study was to evaluate the long-term efficacy of dual-hemisphere repetitive transcranial magnetic stimulation (rTMS) on poststroke aphasia. METHODS: Thirty patients with subacute poststroke nonfluent aphasia were randomly allocated to receive real or sham rTMS. Each patient received 1000 rTMS pulses (1 Hz at 110% of resting motor threshold [rMT] over the right unaffected Broca's area and 1000 pulses (20 Hz at 80% rMT) over the left affected Broca's area for 10 consecutive days followed by speech/language training. The language section of the Hemispheric Stroke Scale (HSS), the Stroke Aphasic Depression Questionnaire-Hospital Version (SADQ-H), and the National Institutes of Health Stroke Scale (NIHSS) were measured before, immediately after the 10 sessions, and 1 and 2 months after the last session. RESULTS: At baseline, there were no significant differences between groups in demographic and clinical rating scales. However, there was a significantly greater improvement in the HSS language score as well as in the SADQ-H after real rTMS compared with sham rTMS, which remained significant 2 months after the end of the treatment sessions. CONCLUSION: This is the first clinical study of dual-hemisphere rTMS in poststroke aphasia. Combining dual-hemisphere rTMS with language training might be a feasible treatment for nonfluent aphasia; further multicenter studies are needed to confirm this result.

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BACKGROUND: Because there have been no epidemiological studies of stroke in Egypt, a community-based survey was conducted in the Assiut Governorate to estimate the prevalence and risk factors of stroke in our community. METHODS: A three-phase door-to-door study was performed in which 6,498 participants were chosen by random sampling from 7 districts in Assiut (first phase). Out of this sample, 578 dropped out leaving 3,066 males (51.8%) and 2,854 females (48.2%). There were 3,660 (61.8%) urban residents and 2,260 (38.2%) from the rural community. In the second phase participants were screened using the questionnaire for stroke, while the third phase involved medical evaluation of all suspected cases, with diagnosis of stroke confirmed by evaluation of CT scans. The Mini Mental State Examination and Hamilton Depression Scale were evaluated for each patient. RESULTS: 65 participants were identified as positive on the survey questionnaire, but only 57 patients were found to have stroke, giving a crude prevalence rate of 963/100,000 inhabitants with an age-adjusted local prevalence rate of 699.2/100,000 and an age-adjusted prevalence relative to the standard world population of 980.9/100,000. The prevalence among males was higher than females (1174/100,000 vs. 736/100,000) with a ratio 1.7:1. There was a significantly higher prevalence of ischemic (895/100,000) than hemorrhagic (68/100,000) stroke. Stroke prevalence was the same in rural and urban areas and in males and females. There was, however, a significantly higher prevalence in illiterate (2413/100,000) than literate participants (357/100,000). Forty-two patients (73.7%) had one or more risk factors for stroke, hypertension being the commonest (66%) and diabetes mellitus second (38.6%). Nine cases had poststroke dementia (15.8%) and 14 cases (24.6%) had mild depression. CONCLUSIONS: The overall prevalence rate of stroke is high, especially in older adults, men and illiterate individuals. A higher prevalence of ischemic than hemorrhagic stroke was recorded, with hypertension and diabetes mellitus being the commonest risk factors in our community.

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The aim of the study was to compare the long-term efficacy of high versus low frequency repetitive transcranial magnetic stimulation (rTMS), applied bilaterally over the dorsolateral prefrontal cortex (DLPFC), on cognitive function and cortical excitability of patients with Alzheimer's disease (AD). Forty-five AD patients were randomly classified into three groups. The first two groups received real rTMS over the DLPFC (20 and 1 Hz, respectively) while the third group received sham stimulation. All patients received one session daily for five consecutive days. In each session, rTMS was applied first over the right DLPFC, immediately followed by rTMS over the left DLPFC. Mini Mental State Examination (MMSE), Instrumental Daily Living Activity (IADL) scale and the Geriatric Depression Scale (GDS) were assessed before, after the last (fifth) session, and then followed up at 1 and 3 months. Neurophysiological evaluations included resting and active motor threshold (rMT and aMT), and the duration of transcallosal inhibition (TI) before and after the end of the treatment sessions. At base line assessment there were no significant differences between groups in any of the rating scales. The high frequency rTMS group improved significantly more than the low frequency and sham groups in all rating scales (MMSE, IADL, and GDS) and at all time points after treatment. Measures of cortical excitability immediately after the last treatment session showed that treatment with 20 Hz rTMS reduced TI duration. These results confirm that five daily sessions of high frequency rTMS over the left and then the right DLPFC improves cognitive function in patients with mild to moderate degree of AD. This improvement was maintained for 3 months. High frequency rTMS may be a useful addition to therapy for the treatment of AD.

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