Imaging neuroscience (Cambridge, Mass.)
January 1, 2025
Sebastian Ehmann, Idil Sezer, Isaac N Treves et al.
9 citations
Long-term meditators show a distinct pattern of cognitive and neural changes from prolonged mindfulness practice, including enhanced sensory integration, reduced negative emotional responses to pain, more rational decision-making, and altered self-awareness. Neuroimaging reveals increased activation in brain networks linked to interoception and pain (salience network), reduced connectivity between executive and salience networks, diminished fear and amygdala activation, and altered default-mode network activity associated with emotional neutrality and non-ordinary states of consciousness. Methodological limitations prevent firm conclusions about lasting trait effects, and a unified neurophenomenological framework is needed to systematically study advanced meditation's states and stages.
Imaging neuroscience (Cambridge, Mass.)
January 1, 2026
Hongkeun Kim
Why some moments are remembered while others are forgotten involves a dissociation in large-scale brain networks. A meta-analysis of 56 fMRI studies using the subsequent memory paradigm found that brain activity linked to forgetting is consistent across different tasks, recruiting specific subsystems within the default mode, frontoparietal, and ventral attention networks—a pattern suggesting distraction or mind-wandering. In contrast, activity supporting successful memory encoding is task-specific: verbal encoding engages language-related networks, while pictorial encoding activates visuo-perceptual systems. This indicates that encoding failure may stem from similar attentional lapses regardless of context, whereas successful encoding requires precise, context-sensitive neural engagement.
Imaging neuroscience (Cambridge, Mass.)
January 1, 2025
Brandon Taraku, Jason S Nomi, Artemis Zavaliangos-Petropulu et al.
Ketamine treatment alters how brain networks dynamically interact in people with treatment-resistant depression. After four ketamine infusions over two weeks, patients spent less time in a visual-network brain state and more time in a central-executive-network state. Transitions between the salience network and central executive network increased, while salience-to-visual transitions decreased. Reduced time in the salience-network state was linked to less rumination. Before treatment, depressed patients differed from healthy controls in these same dynamic patterns, suggesting ketamine may shift network dynamics toward a healthier profile.
Imaging neuroscience (Cambridge, Mass.)
January 1, 2024
Hanna Molla, Giovanni Novembre, Anya K. Bershad et al.
MDMA increases the perceived pleasantness of touch, but the neural mechanisms are not well understood. In a double-blind, randomized, within-subject fMRI study with 18 healthy participants, MDMA (1.5 mg/kg) compared to placebo enhanced affective ratings of gentle touch at both a slower, more pleasant speed (3 cm/s) and a faster, less pleasant speed (30 cm/s). Plasma oxytocin levels also increased more during the MDMA session. On the neural level, primary sensorimotor areas showed greater hemodynamic changes during MDMA for both touch speeds, indicating an early influence within somatosensory pathways. Changes in oxytocin levels interacted with the drug in area MT+, associated with motion perception. However, the posterior insula did not show preferential activation for the slower stroking speed.
Imaging neuroscience (Cambridge, Mass.)
January 1, 2026
Ankan Biswas, Srishty Aggarwal, Kanishka Sharma et al.
Long-term meditators show stronger stimulus-induced gamma oscillations and steeper power spectral density slopes compared to matched controls, suggesting enhanced inhibitory function. Both stimulus-induced and stimulus-free gamma coexist during meditation but arise from different brain regions—occipital and fronto-temporal respectively—indicating distinct mechanisms. Meditation-induced broadband gamma localizes to fronto-temporo-parietal regions, with stronger effects in parietal areas of meditators, while stimulus-induced gamma is stronger in occipital areas. Meditators also report higher mindfulness, lower stress, and more mystical experiences, though these traits do not correlate with gamma power. These findings suggest meditation may boost inhibitory mechanisms and mitigate age-related neural decline.
Imaging neuroscience (Cambridge, Mass.)
January 1, 2026
Tiara Bounyarith, David Braun, Aaron Kucyi
A new method called real-time fMRI-triggered experience sampling (rt-fMRI-ES) was developed to capture spontaneous thoughts with better temporal precision. In 42 to 49 participants at rest, brain activity in the posteromedial cortex (a default mode network region) was used to trigger thought probes. When probes were triggered by activity in this region, participants reported lower external attention compared to other trials, supporting the hypothesis that default mode network activity relates to internally focused thought. However, the hypothesis that dorsal anterior insular cortex activity would correspond to higher arousal ratings was not supported. The method offers a way to study spontaneous thought based on ongoing neural activity.
Imaging neuroscience (Cambridge, Mass.)
January 1, 2025
Ruiqi Chen, Matthew Singh, Todd S Braver et al.
Resting-state brain activity may reflect a nonlinear dynamical system with multiple attractors rather than noise-driven fluctuations around a single stable state. Whole-brain dynamical systems models built from individual resting-state fMRI recordings, using the MINDy framework, revealed a diverse taxonomy of attractor landscapes including multiple equilibria and limit cycles. When projected into anatomical space, these attractors mapped onto a limited set of canonical resting-state networks, such as the default mode network and frontoparietal control network, which were reliable at the individual level. Creating convex combinations of models induced bifurcations that recapitulated the full spectrum of found dynamics, suggesting the resting brain traverses diverse dynamics generating distinct but anatomically overlapping attractor landscapes.
Imaging neuroscience (Cambridge, Mass.)
January 1, 2023
Ioanna Amaya, Marianna E. Schmidt, Marie T Bartossek et al.
Flicker light stimulation (FLS) induces hyperconnectivity between the lateral geniculate nucleus (LGN) and early visual areas, as well as proximal upstream areas of the ventral visual stream (e.g., hV4, VO1). An exploratory analysis indicates that higher-order thalamic nuclei, such as the anterior and mediodorsal nuclei, are strongly affected by FLS, with connectivity changes to upstream cortical visual areas directly reflecting a frequency-dependent increase in experienced visual phenomena. These findings help identify specific thalamocortical interactions involved in the emergence of visual hallucinations.