Comparing cognition, coping skills and vedic personality of individuals practicing yoga, physical exercise or sedentary lifestyle: a cross-sectional fMRI study

The neurobiological effects of mind-body exercise: a systematic review and meta-analysis of neuroimaging studies

The neurobiological effects of mind-body exercise on brain activation, functional neural connections and structural changes in the brain remain elusive. This systematic review and coordinate-based meta-analysis investigated the changes in resting-state and task-based brain activation, as well as structural brain changes before and after mind-body exercise compared to waitlist or active controls based on published structural or functional magnetic resonance imaging randomized controlled trials or cross-sectional studies. Electronic database search and manual search in relevant publications yielded 34 empirical studies with low-to-moderate risk of bias (assessed by Cochrane risk-of-bias tool for randomized trials or Joanna Briggs Institute's critical appraisal checklist for analytical cross-sectional studies) that fulfilled the inclusion criteria, with 26 studies included in the narrative synthesis and 8 studies included in the meta-analysis. Coordinate-based meta-analysis showed that, while mind-body exercise enhanced the activation of the left anterior cingulate cortex within the default mode network (DMN), it induced more deactivation in the left supramarginal gyrus within the ventral attention network (uncorrected ps < 0.05). Meta-regression with duration of mind-body practice as a factor showed that, the activation of right inferior parietal gyrus within the DMN showed a positive association with increasing years of practice (voxel-corrected p < 0.005). Although mind-body exercise is shown to selectively modulate brain functional networks supporting attentional control and self-awareness, the overall certainty of evidence is limited by small number of studies. Further investigations are needed to understand the effects of both short-term and long-term mind-body exercise on structural changes in the brain.PROSPERO registration number: CRD42021248984.

Composition of yoga-philosophy based mental traits (Gunas) in major psychiatric disorders: A trans-diagnostic approach

Yoga philosophy includes the theory of Tri-guna (three mental traits): sattva (signifies a tendency to 'goodness'), rajas (tendency towards 'activity'), and tamas (tendency towards "inertia"). This cross-sectional study aimed to understand the differences in the expression of gunas in patients suffering from major psychiatric disorders (n = 113, 40 females) and age-gender-education-matched healthy controls (HCs; n = 113, 40 females). Patients were diagnosed by a psychiatrist using DSM 5 criteria and suffered from the following disorders: depression (n = 30), schizophrenia (SCZ; n = 28), obsessive-compulsive disorder (OCD; n = 23), anxiety (n = 16), and bipolar affective disorder (BPAD; n = 16). Tri-gunas were assessed using a validated tool (Vedic Personality Inventory) and symptoms were assessed using standard scales as per the diagnosis. Multi-variate analysis of variance (MANOVA) was used to assess the differences in guna scores between HCs and patients, and between patients with different diagnoses. A two-tailed Pearson correlation was performed between the gunas and psychometric scales. Results revealed that HCs had significantly higher sattva traits as compared to patients (except those with OCD). Each psychiatric diagnosis also showed a specific guna configuration: (1) Anxiety disorders and OCD: High sattva-rajas, low tamas; (2) Depression: High sattva-tamas, low rajas; (3) Psychotic disorders (SCZ/BPAD): High tamo-rajas, low sattva. Significant positive correlations were observed between rajas traits and anxiety/OC/positive psychotic symptoms, negative psychotic symptoms and tamas traits, and sattva traits and OC symptoms. This finding has clinical implications, both to develop ways of predicting outcomes of psychiatric disorders, as well as to develop psycho-therapeutic and lifestyle interventions targeting the gunas.

Effects of preventive interventions on neuroimaging biomarkers in subjects at-risk to develop Alzheimer's disease: A systematic review

Alzheimer's Disease (AD) is a multifactorial and complex neurodegenerative disorder. Some modifiable risk factors have been associated with an increased risk of appearance of the disease and/or cognitive decline. Preventive clinical trials aiming at reducing one or combined risk factors have been implemented and their potential effects assessed on cognitive trajectories and on AD biomarkers. However, the effect of interventions on surrogate markers, in particular imaging biomarkers, remains poorly understood. We conducted a review of the literature and analyzed 43 interventional studies that included physical exercise, nutrition, cognitive training or multidomain interventions, and assessed various brain imaging biomarkers, to determine the effects of preventive interventions on imaging biomarkers for subjects at-risk to develop AD. Deciphering the global and regional brain effect of each and combined interventions will help to better understand the interplay relationship between multimodal interventions, cognition, surrogate brain markers, and to better design primary and secondary outcomes for future preventive clinical trials. Those studies were pondered using generally-admitted quality criteria to reveal that interventions may affect the brain of patients with cognitive impairment rather than those without cognitive impairment thus indicating that particular care should be taken when selecting individuals for interventions. Additionally, a majority of the studies concurred on the effect of the interventions and particularly onto the frontal brain areas.