Amygdala structure and function and its associations with social-emotional outcomes in a low-risk preterm sample.

Amygdala atypical volume development and functional connectivity (FC) at small gestational ages (GA) have been found across childhood. This adult-oriented study assesses whether altered amygdala structure and function is present following low-risk preterm birth. T1-weighted and resting-state functional MRI images of 33 low-risk preterm (30-36 weeks' GA) and 29 full-term (37-42 weeks' GA) young adults of both sexes, aged between 20 and 32 years old, were analyzed using FreeSurfer (v6.0.0) and Coon Toolbox (v21.a). The social-emotional assessment included Happé's Strange Stories Test, the Moral Judgment Test, Delay-Discounting Test, Adult Self Report, and Emotion Regulation Questionnaire. No differences were found in social-emotional outcomes or amygdala volumes between the groups. Low-risk preterm young adults showed increased FC between the left amygdala, right amygdala and medial frontal cortex (MedFC) (F = 9.89, p-FWE = 0.009) at cluster level compared to their full-term peers. However, significant results at connection level were not observed between left and right amygdala. Lastly, increased FC at cluster level between the right amygdala and MedFC, and left amygdala and MedFC, was related to better social-emotional outcomes only in low-risk preterm young adults (F = 6.60, p-FWE = 0.036) at cluster level. At connection level, in contrast, only right amygdala-MedFC increased FC was significantly associated with better social-emotional outcomes. This study reveals that low-risk prematurity does not have an effect on social-emotional outcomes or structural amygdala volumes during young adulthood. However, individuals who were considered to be at a lower risk of exhibiting neurodevelopmental alterations following preterm birth demonstrated increased FC between the left and right amygdala and MedFC.

Long-term effects of cognitive rehabilitation on brain, functional outcome and cognition in Parkinson's disease.

BACKGROUND AND PURPOSE: Cognitive rehabilitation has demonstrated efficacy in producing short-term cognitive and brain changes in patients with Parkinson's disease (PD). To date, no study has assessed the long-term effects of cognitive rehabilitation using neuroimaging techniques in PD. The aim was to assess the longitudinal effects of a 3-month cognitive rehabilitation programme evaluating the cognitive, behavioural and neuroimaging changes after 18 months. METHODS: Fifteen patients with PD underwent a cognitive, behavioural and neuroimaging assessment at pre-treatment (T0 ), post-treatment (T1 ) and after 18 months (T2 ). This study examined the long-term effects (from T0 to T2 ) and the maintenance of the changes (from T1 to T2 ). T1-weighted, diffusion-weighted, functional magnetic resonance imaging during both a resting-state and a memory paradigm were acquired. Voxel-based morphometry and tract-based spatial statistics were used for grey and white matter analyses. A region-of-interest-to-region-of-interest approach was used for resting-state functional connectivity (FC) and a model-based approach was used for brain activation during the memory paradigm. RESULTS: Patients with PD showed increased cognitive performance, decreased functional disability, increased brain FC and activation at T2 compared with T0 (P < 0.05, FDR). Moreover, patients showed maintenance of the improvements in cognition and functionality, and maintenance of the increased brain FC and activation at T2 compared with T1 . However, significant grey matter reduction and alterations of white matter integrity were found at T2 (P < 0.05, FWE). CONCLUSIONS: Findings suggest that the improved cognitive performance and increased brain FC and activation after cognitive rehabilitation were significantly maintained after 18 months in patients with PD, despite the structural brain changes, consistent with a progression of neurodegenerative processes.