Summary
Frequency-dependent reorganization of the primary somatosensory cortex, together with perceptual changes, arises following repetitive sensory stimulation. Here, we investigate the role of GABA in this process. We co-stimulated two finger tips and measured GABA and Glx using magnetic resonance (MR) spectroscopy at the beginning and end of the stimulation. Participants performed a perceptual learning task before and after stimulation. There were 2 sessions with stimulation frequency either at or above the resonance frequency of the primary somatosensory cortex (23 and 39 Hz, respectively). Perceptual learning occurred following above resonance stimulation only, while GABA reduced during this condition. Lower levels of early GABA were associated with greater perceptual learning. One possible mechanism underlying this finding is that cortical disinhibition “unmasks” lateral connections within the cortex to permit adaptation to the sensory environment. These results provide evidence in humans for a frequency-dependent inhibitory mechanism underlying learning and suggest a mechanism-based approach for optimizing neurostimulation frequency.
Pineapple juice (PJ) is used in Magnetic Resonance Cholangiopancreatography to suppress gastrointestinal tract signals. To explore how PJ affects multiparametric liver MRI, 30 participants underwent scans before and after ingesting PJ. Image data were analysed with LiverMultiScan (yielding iron corrected T1 (cT1), iron, and PDFF) and statistically compared. The changes post PJ administration were statistically significant for cT1 at both 1.5T and 3T but not for iron and PDFF. However, the repeatability analysis indicates the post PJ administration cT1 changes were smaller than the repeatability limits of agreement, suggesting that PJ has neglect-able clinical effect on multiparametric liver MRI.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.