Brain Changes in Long-Term Zen Meditators Using Proton Magnetic Resonance Spectroscopy and Diffusion Tensor Imaging: A Controlled Study

Introduction: This work aimed to determine whether 1H magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) are correlated with years of meditation and psychological variables in long-term Zen meditators compared to healthy non-meditator controls. Materials and Methods: Design. Controlled, cross-sectional study. Sample. Meditators were recruited from a Zen Buddhist monastery. The control group was recruited from hospital staff. Meditators were administered questionnaires on anxiety, depression, cognitive impairment and mindfulness. 1H-MRS (1.5 T) of the brain was carried out by exploring four areas: both thalami, both hippocampi, the posterior superior parietal lobule (PSPL) and posterior cingulate gyrus. Predefined areas of the brain were measured for diffusivity (ADC) and fractional anisotropy (FA) by MR-DTI. Results: Myo-inositol (mI) was increased in the posterior cingulate gyrus and Glutamate (Glu), N-acetyl-aspartate (NAA) and N-acetyl-aspartate/Creatine (NAA/Cr) was reduced in the left thalamus in meditators. We found a significant positive correlation between mI in the posterior cingulate and years of meditation (r = 0.518; p = .019). We also found significant negative correlations between Glu (r =20.452; p = .045), NAA (r =20.617; p = .003) and NAA/Cr (r =20.448; P = .047) in the left thalamus and years of meditation. Meditators showed a lower Apparent Diffusion Coefficient (ADC) in the left posterior parietal white matter than did controls, and the ADC was negatively correlated with years of meditation (r =20.4850, p = .0066). Conclusions: The results are consistent with the view that mI, Glu and NAA are the most important altered metabolites. This study provides evidence of subtle abnormalities in neuronal function in regions of the white matter in meditators

Traumatic dental injuries and attention-deficit/hyperactivity disorder: is there a link?

Traumatic dental injuries (TDIs) constitute a major cause of morbidity among children worldwide. Both TDIs and attention-deficit/hyperactivity disorder (ADHD) are prevalent conditions with similar male-to-female predominance and similar age of presentation. While the commonest causes of TDIs have been identified as playground or sports accidents, a well-known feature of ADHD is accident proneness. Violence, another significant risk factor for TDIs, is more likely to be observed in conduct disorder, a common comorbidity of ADHD. Also, both TDIs and ADHD have been found to be associated with left-handedness. The presence of multiple dental trauma episodes (MDTE), as well as increased risk for non-dental injuries in children with TDIs indicates an underlying persistent condition, which resembles ADHD. Higher point prevalence of mental distress at age 30, found to be associated with increased lifetime prevalence of TDIs, may also be taken as an evidence of a background developmental disorder persisting into adulthood with various comorbidities. In conclusion, this review combines the results of several studies and explains the significance of ADHD as an underlying and predisposing factor for TDIs. Increased awareness and close collaboration between different disciplines involved are essential