Efforts for the Correct Comprehension of Deceitful and Ironic Communicative Intentions in Schizophrenia: A Functional Magnetic Resonance Imaging Study on the Role of the Left Middle Temporal Gyrus.

Deficits in social cognition and more specifically in communication have an important impact on the real-life functioning of people with schizophrenia (SZ). In particular, patients have severe problems in communicative-pragmatics, for example, in correctly inferring the speaker's communicative intention in everyday conversational interactions. This limit is associated with morphological and functional alteration of the left middle temporal gyrus (L-MTG), a cerebral area involved in various communicative processes, in particular in the distinction of ironic communicative intention from sincere and deceitful ones. We performed an fMRI study on 20 patients with SZ and 20 matched healthy controls (HCs) while performing a pragmatic task testing the comprehension of sincere, deceitful, and ironic communicative intentions. We considered the L-MTG as the region of interest. SZ patients showed difficulties in the correct comprehension of all types of communicative intentions and, when correctly answering to the task, they exhibited a higher activation of the L-MTG, as compared to HC, under all experimental conditions. This greater involvement of the L-MTG in the group of patients could depend on different factors, such as the increasing inferential effort required in correctly understanding the speaker's communicative intentions, and the higher integrative semantic processes involved in sentence processing. Future studies with a larger sample size and functional connectivity analysis are needed to study deeper the specific role of the L-MTG in pragmatic processes in SZ, also in relation to other brain areas.

A novel neurocognitive approach for placebo analgesia in neurocognitive disorders.

Neural correlates of placebo analgesia (PA) in patients with neurocognitive disorders have not yet been elucidated. The present study aimed to evaluate how and to what extent executive (dys)functions of the medial prefrontal cortex (MPFC) may be related to PA. To this end, twenty-three subjects complaining of different cognitive deficits (from mild cognitive impairment likely due to Alzheimer's disease to mild AD) were recruited. PA was investigated by a well-known experimental venipuncture pain paradigm (open versus hidden [O-H] application of lidocaine). Patients also underwent a comprehensive neuropsychological evaluation and a functional magnetic resonance imaging (fMRI) GO/No-GO task for eliciting selective activation of the MPFC. Selected neuropsychological variables were correlated to the OH-PA paradigm. The association between the fMRI response on the "No-GO" versus "GO" contrast and PA was investigated over the whole-brain by regression analysis. We showed the existence of a relationship between a lower PA and MPFC dysfunctions through the neuropsychological and fMRI assessment. A separate voxel-based morphometry (VBM) analysis controlled for possible influence of grey matter (GM) volume reduction on both fMRI results and PA. fMRI results were not directly affected by, and therefore independent of, disease-specific GM atrophy, which was indeed located more anteriorly within the rostral anterior cingulate and inversely correlated with PA. Our findings shed new light on the underestimated contribution of executive (dys)functions mediated by the MPFC (response-inhibition, self-monitoring and set-shifting abilities) in PA pathogenesis, with a special purely (i.e. independently from brain structural alterations) functional role played by the MCC. Results are discussed in terms of possible clinical relevance in the management of patients with neurocognitive disorders.