Human brain mapping
May 1, 2020
Joana R A Loureiro, Amber Leaver, Megha Vasavada et al.
65 citations
Both electroconvulsive therapy (ECT) and ketamine reduce amygdala reactivity to positive and negative emotional faces in people with treatment-resistant depression. In a naturalistic study of 44 patients (17 receiving ECT, 27 receiving ketamine), fMRI showed decreased amygdala response after both treatments. Subtle differences between treatments appeared in the dorsolateral prefrontal cortex and insula. Changes in brain activity in the inferior parietal cortex correlated with overall symptom improvement, while frontal region changes correlated with anxiety for negative faces and anhedonia for positive faces. The findings suggest common and distinct neural mechanisms underlying fast-acting antidepressant effects on emotion processing.
Human brain mapping
May 1, 2015
Morten Joensson, Kristine Rømer Thomsen, Lau M Andersen et al.
44 citations
Experiences that become meaningful to the self involve synchronous activity in a paralimbic network of self-awareness and dopaminergic activity, including medial prefrontal and medial parietal/posterior cingulate cortices. Oral administration of 100 mg dopamine improved noetic (conscious) metacognition in minimal self-awareness. In a separate experiment with extended self-awareness, dopamine improved retrieval accuracy of memories of self-judgment (autonoetic metacognition). Magnetoencephalography showed increased power of oscillations preferentially in the medial prefrontal cortex, explaining dopamine's specific effect on explicit self-awareness and autonoetic metacognition.
Human brain mapping
May 1, 2024
Saampras Ganesan, Winson F Z Yang, Avijit Chowdhury et al.
23 citations
In an adept practitioner performing jhana meditation over 5 days inside a 7 Tesla MRI scanner (27 runs), the thalamus and several cortical networks—somatomotor, limbic, default-mode, control, and temporo-parietal—showed good within-subject reliability across all jhanas. When fMRI measurements were adjusted for variability in self-reported phenomenology, other networks such as attention and salience showed noticeable increases in reliability. The findings provide a preliminary template of reliable brain areas likely underpinning core neurocognitive elements of jhana meditation and highlight the value of neurophenomenological designs for characterizing neuronal variability in advanced meditative states.
Human brain mapping
January 1, 2025
Isaac N Treves, Aaron Kucyi, Madelynn Park et al.
8 citations
Trait mindfulness—the tendency to attend to present experience non-judgmentally—is linked to better mental health, but its neural basis remains unclear. In the largest resting-state fMRI study of trait mindfulness to date, involving 367 meditation-naïve adults across three sites, no connections predicted overall trait mindfulness. However, neural models for two subscales, Acting with Awareness and Non-judging, were identified. Positive networks for these subscales involved distinct fronto-parietal and default-mode networks, while negative networks overlapped across subscales and included somatomotor, visual, and default-mode regions. Only negative networks generalized to predict subscale scores in some out-of-sample tests. Predictions negatively correlated with a mind-wandering model. The findings provide preliminary evidence for generalizable connectivity models of mindfulness facets, but incomplete generalization across sites and model overlap highlight the challenge of identifying robust brain markers.
Human brain mapping
April 1, 2025
Clayton R Coleman, Kenneth Shinozuka, Robert Tromm et al.
4 citations
LSD alters consciousness by changing connectivity between the dorsolateral prefrontal cortex (DLPFC), thalamus, and visual areas. In healthy participants, stronger functional connectivity between the left and right DLPFC, thalamus, and fusiform face area correlated with greater ego dissolution. Emotional arousal was linked to increased connectivity between the right DLPFC, intraparietal sulcus, and salience network. A confirmatory reverse analysis supported these findings. Magnetoencephalography data showed that LSD increased theta-band information flow from the thalamus to the DLPFC, supporting the idea that disrupted thalamic gating underlies ego dissolution. The results clarify the DLPFC's role in LSD-induced altered states.
Human brain mapping
June 1, 2025
Wataru Sato, Takanori Kochiyama, Shota Uono
1 citation
Happiness is linked to reduced spontaneous gamma-band neural oscillations in the right precuneus. Using resting-state magnetoencephalography (MEG) in participants who completed happiness questionnaires, researchers found that gamma-band fractional amplitude of low-frequency fluctuation (fALFF) in the right precuneus was negatively associated with subjective happiness scores (partial correlation coefficient = -0.56). This suggests that subjective happiness has a neural electrical correlate in the precuneus, possibly mediated by reduced self-consciousness and heightened inhibitory interneuron activity.
Human brain mapping
February 15, 2025
Harrison Watters, Aleah Davis, Abia Fazili et al.
1 citation
Cortical networks shift their dynamic functional connectivity along a spectrum that tracks the level of external to internal attention demanded by tasks. Networks often grouped into a single task-positive network show divergent responses along this axis, suggesting that defining a single task-positive network is misleading. Somatosensory and visual networks exhibit strong phase shifting along this attentional spectrum. Results were robust at both group and individual levels, supporting network dynamics as a potential individual biomarker. This work provides the first spectrum of dynamic network relationships across an axis of attention, using fMRI data from tasks including moving dots, visual working memory, congruence tasks, resting states, mindfulness meditation, and TV watching.