Effect of Mind Sound Resonance Technique (MSRT – A yoga-based relaxation technique) on psychological variables and cognition in school children: A randomized controlled trial

ObjectiveSchool children undergo stress, which could impact their psychological functions and cognitive abilities. Yoga practices have been found useful in enhancing psychological functions and performance. The current study was planned to evaluate a yoga-based relaxation technique's efficacy as an extracurricular activity on psychological state and cognitive function.Design and settingThis study was a parallel-group randomized controlled trial conducted at a government school in south India.ParticipantsSixty students with age ranging between 14–16 years (mean age ± SD; 15.3 ± 0.71 years) satisfying the inclusion and exclusion criteria were randomized to experimental and control groups with an allocation ratio of 1:1.InterventionExperimental group received Mind Sound Resonance Technique (MSRT), whereas the control group performed supine rest (SR) for two-weeks.Outcome measuresParticipants were assessed with State trait anxiety inventory - short form, Mind Wandering Questionnaire, State Mindfulness Attention Awareness Scale, and Trail making task at baseline and post-intervention.ResultsExperimental group showed a reduction in state anxiety and mind wandering with improvement in state mindfulness and performance in the Trail-making task compared to the control group.ConclusionResults of the current trial indicate the beneficial role of MSRT in enhancing psychological and cognitive functions in children. Further, large-scale trials are warranted to ascertain the usefulness of the technique.     

Thalamic volume mediates associations between cardiorespiratory fitness (VO2max) and cognition in Parkinson's disease

IntroductionCognitive deficits occur in Parkinson's disease (PD). Cardiorespiratory fitness (CRF) is associated with better cognitive performance in aging especially in executive function (EF) and memory. The association between CRF and cognitive performance is understudied in people with PD. Brain structures underlying associations also remains unknown. This cross-sectional study examined the associations between CRF and cognitive performance in PD. We also examined associations between CRF and brain structures impacted in PD. Mediation analysis were conducted to examine whether brain structures impacted in PD mediate putative associations between CRF and cognitive performance.MethodsIndividuals with PD (N = 33) underwent magnetic resonance imaging (MRI), CRF evaluation (estimated VO₂max), and neuropsychological assessment. Composite cognitive scores of episodic memory, EF, attention, language, and visuospatial functioning were generated. Structural equation models were constructed to examine whether MRI volume estimates (thalamus and pallidum) mediated associations between CRF and cognitive performance (adjusting for age, education, PD disease duration, sex, MDS-UPDRS motor score, and total intracranial volume).ResultsHigher CRF was associated with better episodic memory (Standardized β = 0.391; p = 0.008), EF (Standardized β = 0.324; p = 0.025), and visuospatial performance (Standardized β = 0.570; p = 0.005). Higher CRF was associated with larger thalamic (Standardized β = 0.722; p = 0.004) and pallidum (Standardized β = 0.635; p = 0.004) volumes. Thalamic volume mediated the association between higher CRF and better EF (Indirect effect = 0.309) and episodic memory (Indirect effect = 0.209) performance (p < 0.05). The pallidum did not significantly mediate associations between CRF and cognitive outcomes.ConclusionThe thalamus plays an important role in the association between CRF and both EF and episodic memory in PD.     

Neuropsychological outcomes after thalamic deep brain stimulation for essential tremor

IntroductionNon-motor DBS outcomes have received little attention in ET relative to PD. This study examines neuropsychological outcomes in ET following thalamic VIM DBS.MethodsFifty patients completed neuropsychological evaluations preoperatively and approximately seven months postoperatively. Cognition and mood changes were analyzed at the group level and individual level. Additional associations with treatment, disease, and demographic characteristics were assessed.ResultsSignificant cognitive decline was not observed at the group level. At the individual level, 46% of patients demonstrated at least subtle overall cognitive decline (≥1SD on at least one test within at least two domains). Mild decline (≥1SD) was seen in 10%–29.17% of patients on individual tests across all cognitive domains, with highest rates in verbal memory. Substantial cognitive decline (≥2SD) occurred in less than 9% of the sample across all tests. Factors related to cognitive decline included higher DBS parameter settings, older age of ET onset, intracranial complications, and inability to reduce ET medications postoperatively. Depression and anxiety did not change when accounting for questionnaire items that could be falsely elevated by tremor.ConclusionSubstantial cognitive decline after VIM DBS is rare in patients with ET. However, subtle decrements can occur across cognitive domains and particularly in verbal memory. DBS parameter settings may relate to cognitive decline. Further research is needed to better understand possible associations with electrode lateralization and other variables that could also relate to disease progression and test-retest effects. Symptoms of depression and anxiety remain stable.     

Cognitive and psychosocial effects of an acute sun salutation intervention among adults with stress

Evidence suggests that yoga can improve executive functioning (EF) and psychological well-being, but there is no evidence whether flow-based, moderate-intensity forms of yoga can deliver similar benefits. The purpose of this randomized controlled trial was to test the aforementioned effects of engaging in a 30-min, video-guided sun salutation exercise (n = 25), relative to aerobic exercise (n = 22) and attentional control (n = 24). Low-active participants (Mage = 27.84; 87.3% female), with symptoms of stress, completed psychosocial assessments and tasks assessing EF, before and after the session. Results showed a significant group difference for state anxiety (p = .01, η_p² = 0.13) and stress (p < .05, η_p² = 0.09), in favor of the yoga group. No significant between-groups differences in EF were observed. Results suggest that video-guided, flow-based forms of yoga can induce immediate improvements in well-being, yet extended involvement may be required to realize performance improvements in memory and processing speed.     

Modifiable lifestyle factors and cognitive reserve: A systematic review of current evidence

This systematic review aims to summarize cognitive reserve (CR) evaluation approaches and to examine the role of seven selected modifiable lifestyle factors (diet, smoking, alcohol consumption, physical activity, cognitive leisure activity, sleep, and meditation) in mitigating the impacts of age- or disease-related brain changes on cognition. Eighteen population-based English empirical studies were included. We summarize the study designs and identify three CR models that were broadly used in these studies, including a residual model assessing lifestyle factors in relation to unexplained variance in cognition after accounting for brain markers, a moderation model testing whether lifestyle factors moderate the relationship between brain status and cognition, and a controlling model examining the associations between lifestyle factors and cognition when controlling for brain measures. We also present the findings for the impact of each lifestyle factor. No studies examined diet, sleep, or meditation, and only two studies focused on smoking and alcohol consumption each. Overall, the studies suggest lifestyle activity factors (physical and cognitive leisure activities) may contribute to CR and attenuate the damaging impact of brain changes on cognition. Standardized measurements of lifestyle factors and CR are needed, and mechanisms underlying CR need to be further addressed as well.     

The conflicted practice: Municipal occupational therapists’ experiences with assessment of clients with cognitive impairments

Background: The practice of Norwegian occupational therapists (OTs) in municipal practice is a little explored area and with the Coordination Reform Act from 2012, Norwegian OTs in municipal practice have received responsibilities concerning clients with cognitive impairments. The aim of this study was to explore municipal OTs experiences with assessment of clients with cognitive impairments.

Method: Fourteen individual interviews with OTs who worked with clients with cognitive impairments, were conducted. An inductive thematic analysis, using text condensation and coding, was performed.

Results: The results revealed three themes; power of occupation, advantages and disadvantages of assessments used and the need for competencies within municipal services. The participants emphasized using observation in the assessment process and reflected on pros and cons of the standardized assessment tools they used. They expressed a need for competence development, although it was difficult to prioritize to do so.

Conclusion: This study illustrated a conflicted practice related to choices OTs make in their practices. They valued the importance of working occupation based, however, they chose to use impairment based standardized assessments. They expressed a need to engage in professional development, but due to heavy workloads, the limited power they experienced and lack of knowledge, this was difficult.     

Medium Chain Triglycerides induce mild ketosis and may improve cognition in Alzheimer’s disease. A systematic review and meta-analysis of human studies

Introduction/aimThe brain in Alzheimer’s disease shows glucose hypometabolism but may utilize ketones for energy production. Ketone levels can potentially be boosted through oral intake of Medium Chain Triglycerides (MCTs). The aim of this meta-analysis is to investigate the effect of MCTs on peripheral ketone levels and cognitive performance in patients with mild cognitive impairment and Alzheimer’s disease.MethodsMedline, Scopus and Web of Science were searched for literature up to March 1, 2019. Meta-analyses were performed by implementing continuous random-effects models and outcomes were reported as weighted Mean Differences (MDs) or Standardized Mean Differences (SMDs).ResultsTwelve records (422 participants) were included. Meta-analysis of RCTs showed that, compared with placebo, MCTs elevated beta-hydroxybutyrate [MD = 0.355; 95 % CI (0.286, 0.424), I² = 0 %], showed a trend towards cognitive improvement on ADAS-Cog [MD = −0.539; 95% CI (−1.239, −0.161), I² = 0 %], and significantly improved cognition on a combined measure (ADAS-Cog with MMSE) [SMD = −0.289; 95 % CI (−0.551, −0.027), I² = 0 %].ConclusionsIn this meta-analysis, we demonstrated that MCTs can induce mild ketosis and may improve cognition in patients with mild cognitive impairment and Alzheimer’s disease. However, risk of bias of existing studies necessitates future trials.     

Disruption of hippocampal rhythms via optogenetic stimulation during the critical period for memory development impairs spatial cognition

BackgroundHippocampal oscillations play a critical role in the ontogeny of allocentric memory in rodents. During the critical period for memory development, hippocampal theta is the driving force behind the temporal coordination of neuronal ensembles underpinning spatial memory. While known that hippocampal oscillations are necessary for normal spatial cognition, whether disrupted hippocampal oscillatory activity during the critical period impairs long-term spatial memory is unknown. Here we investigated whether disruption of normal hippocampal rhythms during the critical period have enduring effects on allocentric memory in rodents.Objective/hypothesisWe hypothesized that disruption of hippocampal oscillations via artificial regulation of the medial septum during the critical period for memory development results in long-standing deficits in spatial cognition.MethodsAfter demonstrating that pan-neuronal medial septum (MS) optogenetic stimulation (465 nm activated) regulated hippocampal oscillations in weanling rats we used a random pattern of stimulation frequencies to disrupt hippocampal theta rhythms for either 1Hr or 5hr a day between postnatal (P) days 21–25. Non-stimulated and yellow light-stimulated (590 nm) rats served as controls. At P50-60 all rats were tested for spatial cognition in the active avoidance task. Rats were then sacrificed, and the MS and hippocampus assessed for cell loss. Power spectrum density of the MS and hippocampus, coherences and voltage correlations between MS and hippocampus were evaluated at baseline for a range of stimulation frequencies from 0.5 to 110 Hz and during disruptive hippocampal stimulation. Unpaired t-tests and ANOVA were used to compare oscillatory parameters, behavior and cell density in all animals.ResultsNon-selective optogenetic stimulation of the MS in P21 rats resulted in precise regulation of hippocampal oscillations with 1:1 entrainment between stimulation frequency (0.5–110 Hz) and hippocampal local field potentials. Across bandwidths MS stimulation increased power, coherence and voltage correlation at all frequencies whereas the disruptive stimulation increased power and reduced coherence and voltage correlations with most statistical measures highly significant (p < 0.001, following correction for false detection). Rats receiving disruptive hippocampal stimulation during the critical period for memory development for either 1Hr or 5hr had marked impairment in spatial learning as measured in active avoidance test compared to non-stimulated or yellow light-control rats (p < 0.001). No cell loss was measured between the blue-stimulated and non-stimulated or yellow light-stimulated controls in either the MS or hippocampus.ConclusionThe results demonstrated that robust regulation of hippocampal oscillations can be achieved with non-selective optogenetic stimulation of the MS in rat pups. A disruptive hippocampal stimulation protocol, which markedly increases power and reduces coherence and voltage correlations between the MS and hippocampus during the critical period of memory development, results in long-standing spatial cognitive deficits. This spatial cognitive impairment is not a result of optogenetic stimulation-induced cell loss.