Executive dysfunction in adults with moyamoya disease is associated with increased diffusion in frontal white matter.

BACKGROUND AND PURPOSE: Alteration of the cerebrovascular reserve (CVR) in the frontal lobes has been associated with cognitive dysfunction in adults with moyamoya disease (MMD). Elevation of the apparent diffusion coefficient (ADC) in normal-appearing white matter on conventional MRI may occur as a consequence of chronic haemodynamic failure. In the present study, the authors examined the relation of ADC with CVR and cognitive dysfunction in adults with MMD. METHODS: The authors measured ADC and CVR in the normal-appearing frontal white matter. CVR was calculated using dynamic susceptibility contrast-enhanced MRI and the acetazolamide challenge. A standardised and validated neuropsychological assessment test battery focusing on executive function was used. RESULTS: 14 patients, 9 women and 5 men (mean age 36.6±12.9 years), were included. The authors found executive dysfunction in 7 of 13 tested patients. ADC and CVR were negatively correlated (Spearman coefficient: -0.46; p=0.015). Elevation of ADC predicted executive dysfunction (area under receiver operating characteristic curve (95% CI): 0.85 (0.59 to 1.16); p=0.032). CONCLUSION: Elevation of ADC in the normal-appearing frontal white matter of adults with MMD was associated with reduced CVR and executive dysfunction. This preliminary study suggests that measurement of ADC might be used to detect patients at risk for cerebral ischaemia and cognitive impairment.

SMR/Theta Neurofeedback Training Improves Cognitive Performance and EEG Activity in Elderly With Mild Cognitive Impairment: A Pilot Study.

Background: Neurofeedback (NF) training, as a method of self-regulation of brain activity, may be beneficial in elderly patients with mild cognitive impairment (MCI). In this pilot study, we investigated whether a sensorimotor (SMR)/theta NF training could improve cognitive performance and brain electrical activity in elderly patients with MCI. Methods: Twenty elderly patients with MCI were assigned to 20 consecutive sessions of sensorimotor (SMR)/theta NF training, during 10 weeks, on a basis of two sessions each week. Neuropsychological assessments and questionnaires, as well as electroencephalogram (EEG), were performed and compared between baseline (T0), after the last NF training session at 10 weeks (T1), and 1-month follow-up (T2). Results: Repeated measures ANOVA revealed that from baseline to post-intervention, participants showed significant improvement in the Montreal cognitive assessment (MoCa, F = 4.78; p = 0.012), the delayed recall of the Rey auditory verbal learning test (RAVLT, F = 3.675; p = 0.032), the Forward digit span (F = 13.82; p < 0.0001), the Anxiety Goldberg Scale (F = 4.54; p = 0.015), the Wechsler Adult Intelligence Score-Fourth Edition (WAIS-IV; F = 24.75; p < 0.0001), and the Mac Nair score (F = 4.47; p = 0.016). EEG theta power (F = 4.44; p = 0.016) and alpha power (F = 3.84; p = 0.027) during eyes-closed resting-state significantly increased after the NF training and showed sustained improvement at a 1-month follow-up. Conclusion: Our results suggest that NF training could be effective to reduce cognitive deficits in elderly patients with MCI and improve their EEG activity. If these findings are confirmed by randomized controlled studies with larger samples of patients, NF could be seen as a useful non-invasive, non-pharmacological tool for preventing further decline, rehabilitation of cognitive function in the elderly. Clinical Trial Registration: This pilot study was a preliminary step before the trial registered in www.ClinicalTrials.gov, under the number of NCT03526692.

Comparison of effects between SMR/delta-ratio and beta1/theta-ratio neurofeedback training for older adults with Mild Cognitive Impairment: a protocol for a randomized controlled trial.

BACKGROUND: Older adults with Mild Cognitive Impairment (MCI) are at high risk of progressing to Alzheimer's disease (AD). Slowing down the effect of dementia by enhancing brain plasticity represents one of the most prominent challenges. Neurofeedback (NF) has shown promising results in improving working memory but has never been evaluated in people with MCI. We aim to examine whether NF training can decrease cognitive disorders, targeting memory, attention functions and brain electrical activity in elderly patients with MCI. METHODS: In this single-blind, randomized controlled trial (RCT) protocol, we will investigate the effects of two NF training protocols on cognitive performances and on brain electrical activity. Sixty MCI patients will be assigned either to an intervention program or to psycho-pedagogical care as a control condition. Participants in the intervention group will attend 30 sessions of sensorimotor/delta-ratio NF training or beta1/theta-ratio NF training. Neuropsychological assessment, questionnaires and electroencephalography (EEG) assessment parameters will be used as dependent variables in three periods: at baseline (T0), immediately after the last NF training session at 4 months (T1) and at 3-month follow-up (T2). The primary outcome will be the change in attention measured with the Trail Making Test B. Secondary outcome will be the changes in cognitive performance and in EEG activities. DISCUSSION: If the results of our study show improvement in cognitive performances of older adults with MCI, this non-invasive, low-cost technique may deserve better consideration as a therapeutic intervention to delay cognitive decline and dementia. Consequently, research in NF will need to review and develop the rigor of its application in gerontology. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT03526692 . Registered on 16 May 2018.

Differential effects of a computerized cognitive stimulation program on older adults with mild cognitive impairment according to the severity of white matter hyperintensities.

OBJECTIVE: This study aimed to explore whether a computerized cognitive stimulation program (CCS) induced differential effects in older adults with mild cognitive impairment (MCI) according to the severity of white matter hyperintensities (WMH), which are associated with cognitive impairment and increased risk of progression to Alzheimer's disease because of the damage they cause to cortical and subcortical networks. PATIENTS AND METHODS: Twenty-nine MCI patients with no or little WMH (MCI-non-WMH) and 22 MCI patients with moderate or severe WMH (MCI-WMH) attended a 24-session CCS program (two sessions per week for a duration of 3 months) focused on executive functions, attention, and processing speed. Cognitive and psychosocial assessments were performed at baseline, postintervention, and 3 months after the intervention. RESULTS: Both groups improved on several cognitive measures after the intervention. However, the MCI-non-WMH group improved on a higher number of cognitive measures than the MCI-WMH group. At postintervention assessment, CCS had a more beneficial effect on the MCI-non-WMH group than on the MCI-WMH group with regard to improving categorical fluency (4.6±6.8 vs 0.4±6.4; effect size=0.37; p=0.002). During the 3-month follow-up assessment, significantly higher score improvements were observed in the MCI-non-WMH group for the paired-associate learning test (6.4±3 vs 4.7±3.5 points; effect size=0.43; p=0.005) as well as categorical fluency (3.8±7.8 vs -0.7±6 points; effect size=0.55; p=0.0003). CONCLUSIONS: These findings suggest that WMH severity was related to cognitive improvement induced by a CCS program and highlight the importance of considering WMH in interventional studies on subjects with MCI.

Computerized cognitive stimulation and engagement programs in older adults with mild cognitive impairment: comparing feasibility, acceptability, and cognitive and psychosocial effects.

PURPOSE: Mild cognitive impairment (MCI) is associated with a higher risk of dementia and is becoming a topic of interest for pharmacological and nonpharmacological interventions. With advances in technology, computer-based cognitive exercises are increasingly integrated into traditional cognitive interventions, such as cognitive training. Another type of cognitive intervention involving technology use is cognitive engagement, consisting of involving participants in highly motivational and mentally challenging activities, such as learning to use a form of new digital technology. This study examined the feasibility and acceptability of a computerized cognitive stimulation (CCS) program and a computerized cognitive engagement (CCE) program, and then compared their effects in older adults with MCI. PATIENTS AND METHODS: In this randomized study, data from 19 MCI patients were analyzed (n=9 in CCS and n=10 in CCE). The patients attended a group weekly session for a duration of 3 months. Assessments of cognitive and psychosocial variables were conducted at baseline (M0) and at the end of the programs (M3). RESULTS: All of the participants attended the 12 sessions and showed a high level of motivation. Attrition rate was very low (one dropout at M3 assessment). At M3, the CCS participants displayed a significant improvement in part B of the Trail Making Test (TMT-B; p=0.03) and self-esteem (p=0.005), while the CCE participants showed a significant improvement in part A of the Trail Making Test (TMT-A; p=0.007) and a higher level of technology acceptance (p=0.006). The two groups did not differ significantly (p>0.05) in cognitive and psychosocial changes after the intervention. However, medium effect sizes (Cohen's d=0.56; 95% CI =-0.43:1.55) were found on the free recall, favoring the CCS group, as well as on TMT-A (d=0.51; 95% CI =-0.48:1.49) and technology acceptance (d=-0.65; 95% CI =-1.64:0.34), favoring the CCE group. CONCLUSION: Both interventions were highly feasible and acceptable and allowed improvement in different aspects of cognitive and psychosocial functioning in MCI subjects.

Improvement in cognitive function and cerebral perfusion after bur hole surgery in an adult with moyamoya disease. Case report.

Recent studies have suggested that cognitive impairment may be a common complication in adults with moyamoya disease (MMD). However, the mechanisms of cognitive dysfunction have not been clarified. Whether cognitive impairment may occur as a consequence of cerebral hypoperfusion and may improve after revascularization surgery has not been determined. A 39-year-old West Indian woman with subacute dysexecutive cognitive syndrome and no history of stroke was diagnosed with MMD. Magnetic resonance imaging showed an old, small cerebral infarction in the left frontal white matter and no evidence of recent cerebral ischemia. Perfusion MR imaging with acetazolamide challenge demonstrated a reduced cerebrovascular reserve in both frontal lobes. Revascularization with bur hole surgery was performed, which resulted in complete regression of initial cognitive impairment. Improvement in cognitive function correlated with the development of transdural collaterals on angiography and improvement in cerebral perfusion on MR imaging. This case suggests a relationship between cognitive dysfunction and cerebral hypoperfusion in MMD. Cognitive impairment may be potentially reversible after bur hole surgery and cerebral perfusion improvement.

Correlation between cognitive impairment and cerebral hemodynamic disturbances on perfusion magnetic resonance imaging in European adults with moyamoya disease. Clinical article.

OBJECT: Although cognitive impairment has been reported in adults with moyamoya disease (MMD), its relationship with cerebral hemodynamic disturbances has not been investigated. The aims of the present study were to confirm the presence of dysexecutive cognitive syndrome (DCS) in adults with MMD and to explore the relationship of DCS with frontal lobe perfusion as measured by perfusion MR imaging. METHODS: Cerebral blood volume (CBV) ratio and mean transit time delay were measured in frontal and temporoparietal regions using the cerebellum as a reference region in 10 European adults with MMD. In addition, the authors calculated the cerebrovascular reserve (CVR) using the CBV ratio and the acetazolamide challenge. All patients underwent a standardized neuropsychological assessment test battery. The authors defined DCS as an impairment shown on 3 tests or more of executive function. RESULTS: The authors found DCS in 6 patients. The frontal CVR was lower in patients with DCS than in patients without DCS (mean ± SD: -13.5 ± 13.2% and 20.3 ± 21.3%; p = 0.019, Mann-Whitney U-test). Other parameters of frontal perfusion and temporoparietal CVR were not correlated with DCS. CONCLUSIONS: The authors' findings suggest that DCS is common in European adults with MMD and may be related to frontal perfusion impairment.