Mechanisms Underlying the Prosocial Construction Effect: Detail and Self-referential Processing

There is growing interest in the links between memory and imagination and in their contributions to other cognitive functions. In previous research, imagining oneself helping others increased one’s willingness to help them, and willingness to help correlated with the subjective vividness of imagination (i.e., the prosocial construction effect; PCE). We investigated the degree to which the PCE relies on self-referential processing and on more objectively measured vividness, and the relationship between episodic memory and self-reported trait empathy. We conclude that 1) self-reference is an important but not a necessary component of the PCE; 2) its role may relate to increased feelings of compassion; 3) the PCE is not limited to subjective vividness but can be demonstrated using more objective measures of vividness; and 4) self-reported trait empathy is higher when survey items cue memories of one’s own empathetic behaviour. Implications and avenues for future research are discussed.M.A

Increased Cortical Thickness in Attentional Networks in Parkinson’s Disease with Minor Hallucinations

Hallucinations are common in Parkinson’s disease (PD). Based on functional brain MRI data, hallucinations are proposed to result from alterations in the dorsal attention network (DAN), ventral attention network (VAN), and default mode network. Using structural MRI data from Parkinson’s Progression Markers Initiative (PPMI), we examined cortical thickness in these networks in PD patients with (n=30) and without (n=30) minor hallucinations who were matched on multiple clinical characteristics (e.g., age, sex, education, cognitive diagnosis, MoCA score, medication, disease duration, and severity) as well as healthy controls (n=30) matched on demographic variables. Multivariate analyses revealed mild hallucinations to be associated with thicker cortex in the DAN and VAN, and these effects were driven by the left superior precentral sulcus and postcentral sulcus for the DAN and by the right insular gyrus for the VAN. While these findings may seem at odds with prior work showing grey matter reductions, our patients are in earlier stages of the disease than those in other studies. This is consistent with an inverted U-shape pattern of cortical thickness alterations in other neurodegenerative diseases and warrants further investigations in longitudinal studies tracking brain correlates of PD psychosis progression