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Recent evidence shows that individuals with Anorexia Nervosa (AN) can be characterized by dysfunctional metacognition as well as reductions of gray matter volumes (GMV) in prefrontal brain regions involved in cognitive processes. However, whether these differences are reversible or stable markers has yet to be understood. Thus, we aimed at characterizing metacognition and brain morphometry in individuals recovered from AN (rec-AN). A combined psychometric-brain morphometry investigation on metacognitive functioning in rec-AN individuals was conducted. Fifteen healthy controls (HC) and fifteen rec-AN women underwent a psychometric assessment for metacognitive functioning and a high-resolution T1-weighted Magnetic Resonance Imaging measurement to assess global and regional brain volumes, using Voxel-Based Morphometry. The two groups did not differ for metacognitive functioning and GMV, while regional GMV reductions were observed in rec-AN compared to HC in the left Inferior Frontal Gyrus (IFG). While changes in metacognitive abilities may not represent a stable trait of AN, regional GMV reductions in brain regions devoted to specific cognitive functions, such as inhibitory/top-down control processes, can act as a neurobiological fingerprint for such condition. These findings can represent a promising hint for future investigations on the maintaining factors of AN., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: A promising new approach to cognitive neuroscience based on real-time functional magnetic resonance imaging (rtfMRI) demonstrated that the learned regulation of the neurophysiological activity in circumscribed brain regions can be used as an independent variable to observe its effects on behavior. Here, for the first time, we investigated the modulatory effect of learned regulation of blood oxygenation level-dependent (BOLD) response in the left anterior insula on the perception of visual emotional stimuli., Methods: Three groups of participants (n = 27) were tested: two underwent four rtfMRI training sessions receiving either specific (n = 9) or unspecific feedback (n = 9) of the insula's BOLD response, respectively, and one group used emotional imagery alone (n = 9) without rtfMRI feedback. During training, all groups were required to assess aversive and neutral pictures., Results: Participants able to significantly increase BOLD signal in the target region rated the aversive pictures more negatively. We measured a significant correlation between enhanced left anterior insula activity and increased negative valence ratings of the aversive stimuli. Control groups performing either rtfMRI training with unspecific feedback or an emotional imagery training alone were not able to significantly enhance activity in the left anterior insula and did not show changes in subjective emotional responses., Conclusions: This study corroborates traditional neuroimaging studies demonstrating a critical role of the anterior insula in the explicit appraisal of emotional stimuli and indicates the adopted approach as a potential tool for clinical applications in emotional disorders., (Copyright 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Broca's area is classically associated with speech production. Recently, Broca's area has also been implicated in speech perception and non-linguistic information processing. With respect to the latter function, Broca's area is considered to be a central area in a network constituting the human mirror system, which maps observed or heard actions onto motor programs to execute analogous actions. These mechanisms share some similarities with Liberman's motor theory, where objects of speech perception correspond to listener's intended articulatory gestures. The aim of the current series of behavioral, TMS and fMRI studies was to test if Broca's area is indeed implicated in such audio-motor transformations. More specifically, using a classical phonological rhyme priming paradigm, we investigated whether the role of Broca's area could be purely phonological or rather, is lexical in nature. In the behavioral baseline study, we found a large priming effect in word prime/target pairs (W-W) and no effect for pseudo-words (PW-PW). Online TMS interference of Broca's area canceled the priming difference between W-W and PW-PW by enhancing the effects for PW-PW. Finally, the fMRI study showed activation of Broca's area for W-W pairs, but not for PW-PW pairs. Our data show that Broca's area plays a significant role in speech perception strongly linked to the lexicality of a stimulus., (2009 Elsevier Inc. All rights reserved.)