Striatal functional connectivity associated with Sahaja Yoga meditation

Abstract

Neuroscience research has associated meditation practice with effects on cognitive, motivational and emotional processes. These processes are mediated by several brain circuits, including the striatum and its associated cortical connections. The aim of this study was to focus on the striatum and test how its functional connectivity is affected in long-term practitioners of Sahaja Yoga Meditation. We studied differences between resting and meditation states in a group of 23 Sahaja Yoga Meditation experts. We also compared the resting state between meditation experts and a control group of 23 non-meditating participants. Functional connectivity contrasts between conditions and groups were performed using seeds in the dorsal and ventral striatum (caudate, putamen and nucleus accumbens). During meditation, compared to the resting state, meditators showed altered connectivity between the striatum and parietal, sensorimotor and cerebellar regions. Resting state in meditators relative to that of controls showed reduced functional connectivity between the left accumbens and the mid cingulate, which was correlated with reduced Simon Task interference reaction time effect in meditators. In conclusion, the striatum may play a pivotal role in the practice of Sahaja Yoga Meditation by altering attention and self-referencing, and by modulating bodily sensations. Furthermore, meditation practice could produce long-term changes in striatal connectivity.

Keywords: Attention; Functional connectivity; Interference inhibition; Mental silence; Resting state; Sahaja yoga meditation.

Fig. 1

MS Comparison with RS in meditators: VSi seeds showed reduced FC with somatosensory, motor, premotor and paracentral lobule cortical regions (left VSi (top, MNI coordinates: 3-11 66) and right VSi (bottom, MNI coordinates: 8-34 68)).

Fig. 2

MS Comparison with RS in meditators: Right VSs seed showed increased FC with cerebellar and pons (MNI coordinates: -8 -43 -38).

Fig. 3

MS Comparison with RS in meditators: Left DC seed showed positive FC with the medial superior parietal lobe and occipital lobe (top, MNI coordinates: 18-87 42). Right DC seed showed positive FC with the angular gyrus in addition to parts of the superior parietal area (bottom, MNI coordinates: 35-68 47).

Fig. 4

MS Comparison with RS in meditators: Right VRP seed showed negative FC with a parietal lobe cluster in the supramarginal gyrus (MNI coordinates: -48 -37 45).

Fig. 5

RS comparison between meditators and controls: Left VSi seed showed negative FC with the Mid-cingulate cortex (MNI coordinates: -6 -24 33).

Fig. 6

RS Comparison Between meditators and controls: Left DRP seed showed negative FC with the cerebellum (top, MNI coordinates: 26-66 -18), and positive FC with the dorsomedial/ prefrontal cortex (bottom, MNI coordinates: 18 45 33).

Fig. 7

Overview of the alterations of striatal nuclei´s functional organization related to long-term SYM practice.

Fig. 8

Visual representation of the striatal regions of interest.