AUTHOR=Palermo Sara , Lopiano Leonardo , Morese Rosalba , Zibetti Maurizio , Romagnolo Alberto , Stanziano Mario , Rizzone Mario Giorgio , Geminiani Giuliano Carlo , Valentini Maria Consuelo , Amanzio Martina 

TITLE=Role of the Cingulate Cortex in Dyskinesias-Reduced-Self-Awareness: An fMRI Study on Parkinson’s Disease Patients

JOURNAL=Frontiers in Psychology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2018.01765

DOI=10.3389/fpsyg.2018.01765

ISSN=1664-1078

ABSTRACT=<p><bold>Objectives:</bold> The detection of dyskinesias-reduced-self-awareness (DRSA), in Parkinson’s disease (PD), was previously associated to executive and metacognitive deficits mainly due to dopaminergic overstimulation of mesocorticolimbic circuits. Response-inhibition dysfunction is often observed in PD. Apart from being engaged in response-inhibition tasks, the anterior cingulate cortex (ACC), is part of a functional system based on self-awareness and engaged across cognitive, affective and behavioural contexts. The purpose of the study was to examine the relationship between response-inhibition disabilities and DRSA using whole-brain event-related functional magnetic resonance imaging (fMRI), over the course of a specific executive task.</p><p><bold>Methods:</bold> Twenty-seven cognitively preserved idiopathic PD patients – presenting motor fluctuations and dyskinesias – were studied. They underwent a neurological and neuropsychological evaluation. The presence of DRSA was assessed using the Dyskinesias Subtracted-Index (DS-I). Cingulate functionality was evaluated with fMRI, while patients performed an ACC-sensitive GO-NoGO task. Association between blood oxygenation level dependent response over the whole-brain during the response-inhibition task and DS-I scores was investigated by regression analysis.</p><p><bold>Results:</bold> The presence of DRSA was associated with reduced functional recruitment in the bilateral ACC, bilateral anterior insular cortex and right dorsolateral prefrontal cortex (<italic>p<sub>FWE</sub></italic>&lt;0.05). Moreover, DS-I scores significantly correlated with percent errors on the NoGO condition (<italic>r</italic> = 0.491, <italic>p<sub>FWE</sub></italic> = 0.009).</p><p><bold>Discussion:</bold> These preliminary findings add evidence to the relevant role of executive dysfunctions in DRSA pathogenesis beyond the effects of chronic dopaminergic treatment, with a key leading role played by ACC as part of a functionally impaired response-inhibition network. Imaging biomarkers for DRSA are important to be studied, especially when the neuropsychological assessment seems to be normal.</p>