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Chiappini, E.

Publications and source records attributed to Chiappini, E..

2 recordsLinked to original sources

Optimizing Network-Level TMS-fMRI: Benchmarking a Novel TMS-Compatible "Sushi" MR Coil

Concurrent TMS-fMRI can map how stimulation affects both the targeted cortex and connected brain-wide networks, but this requires MR receive hardware that allows TMS coil placement while preserving reliable whole-brain BOLD sensitivity. We developed and benchmarked a practical TMS-compatible "Sushi" MR receive setup assembled from two flexible 18-channel body arrays. Across six experiments, we tested functional readout validity, signal quality, and active TMS-fMRI compatibility. Resting-state fMRI (n = 12) and verbal N-back task-fMRI (n = 8) were acquired with Sushi, a commercially available 2x7-channel Surface setup, and a standard 64-channel head/neck array. Functional similarity to the 64-channel reference was quantified with spatial overlap, and multi-echo combination (MEcomb) was tested as a post-acquisition signal optimization strategy. Sushi recovered subject-specific resting-state networks that more closely matched the 64-channel reference than Surface, with no significant difference from the 64-channel test-retest reference. For task-fMRI, MEcomb increased task-map similarity for Sushi, whereas setup comparisons within each pipeline were not significant. MEcomb also improved resting-state similarity and increased temporal signal-to-noise ratio (tSNR) across receive setups. In phantom measurements, TMS coil placement produced spatially graded tSNR reductions relative to the no-TMS-coil condition, strongest near the coil. In one participant, active interleaved single-pulse TMS-fMRI over two cortical sites showed no detectable pulse-locked image artifacts; whole-brain MEcomb tSNR during active TMS-fMRI was reduced by 2.6-6.9% relative to the no-coil/no-stimulation reference. Together, Sushi and MEcomb provide complementary hardware and processing tools for TMS-compatible whole-brain fMRI. This combination supports network-level functional readouts while preserving feasibility for active interleaved TMS-fMRI.

neuroscience↗

Effects of dopamine and opioid receptor antagonism on the neural processing of social and non-social rewards

Rewards are a broad category of stimuli inducing approach behavior to aid survival. Extensive evidence from animal research has shown that wanting (the motivation to pursue a reward) and liking (the pleasure associated with its consumption) are mostly regulated by dopaminergic and opioidergic activity in dedicated brain areas. However, less is known about the neuroanatomy of dopaminergic and opioidergic regulation of reward processing in humans, especially when considering different types of rewards (i.e., social and non-social). To fill this gap of knowledge, we combined dopaminergic and opioidergic antagonism (via amisulpride and naltrexone administration) with functional neuroimaging to investigate the neurochemical and neuroanatomical bases of wanting and liking of matched non-social (food) and social (interpersonal touch) rewards, using a randomized, between-subject, placebo-controlled, double-blind design. While at the behavioral level no drug effect was observed, brain activity was modulated by the administered compounds. In particular, opioid antagonism, compared to placebo, was associated with reduced activity in the medial orbitofrontal cortex during consumption of the most valued social and non-social rewards. Dopamine antagonism, however, had no clear effects on brain activity in response to rewards anticipation. These findings provide insights into the neurobiology of human reward processing and suggest a similar opioidergic regulation of the neural responses to social and non-social reward consumption.

neuroscience↗