Short‐term meditation training influences brain energy metabolism: A pilot study on ³¹P MR spectroscopy

Abstract

Background Meditation is increasingly attracting interest among neuroimaging researchers for its relevance as a cognitive enhancement technique and several cross‐sectional studies have indicated cerebral changes. This longitudinal study applied a distinct and standardized meditative technique with a group of volunteers in a short‐term training program to analyze brain metabolic changes. Methods The effect of 7 weeks of meditation exercises (focused attention meditation, FAM) was assessed on 27 healthy volunteers. Changes in cerebral energy metabolism were investigated using 31P‐MR spectroscopy. Metabolite ratios were compared before (T1) and after training (T2). Additional questionnaire assessments were included. Results The participants performed FAM daily. Depression and anxiety scores revealed a lower level of state anxiety at T2 compared to T1. From T1 to T2, energy metabolism ratios showed the following differences: PCr/ATP increased right occipitally; Pi/ATP decreased bilaterally in the basal ganglia and temporal lobe on the right; PCr/Pi increased in occipital lobe bilaterally, in the basal ganglia and in the temporal lobe on the right side. The pH decreased temporal on the left side and frontal in the right side. The observed changes in the temporal areas and basal ganglia may be interpreted as a higher energetic state, whereas the frontal and occipital areas showed changes that may be related to a down‐regulation in ATP turnover, energy state, and oxidative capacity. Conclusions The results of the current study indicate for the first time in a longitudinal study that even short‐term training in FAM may have considerable effects on brain energy state with different local energy management in specific brain regions. Especially higher energetic state in basal ganglia may represent altered function in their central role in complex cerebral distributed networks including frontal and temporal areas. Further studies including different forms of relaxation techniques should be performed for more specific and reliable insights.

Brain Energy Metabolism in Two States of Mind Measured by Phosphorous Magnetic Resonance Spectroscopy

“…After 7 weeks of meditation training, 31 P-MRS was performed during focused attention meditation state using the learned meditative technique, which means that each participant was in a relaxed state, with closed eyes and focusing on breathing, and then repeated in focused attention awake state (psychic wakefulness due to basic mental arithmetic—counting). The 7 weeks of meditative training was performed as described in the study of Gizewski et al ( 2021 ). All volunteers were scanned during evening hours to account for changes throughout the day.…”

“…Yoga nidra is a deep relaxation in lying position, known as “yogic sleep”. This meditation technique was combined with the focused meditation technique, antar mouna including observation of the mind and calming the thoughts of an individual to achieve inner silence (Gizewski et al, 2021 ).…”

“…Five designated brain areas (frontal, parietal, occipital, temporal, and basal ganglia) were analyzed with one or more 31 P-MRS voxels in each volunteer (see Supplementary Material , similar as the study of Gizewski et al, 2021 ). The amount of the included voxels per area depended on the size of the respective area and the quality of the spectra.…”

“…Without determining the relative concentration of absolute values and their change, it is impossible to say which constituent of a certain ratio is to "blame" for the change of that ratio. Gizewski et al ( 2021 ) analyzed a longitudinal part of the study with the same participants and could reveal significant differences in brain metabolism between meditation-naive participants and following 7 weeks of meditation exercise. However, that study, like others before, could analyze only ratios and not the absolute values of metabolites due to significant influences of different coil loadings after position changes.…”