2012), and no studies have investigated the neural basis of patients’ loss of self-awareness regarding a complex socioemotional characteristic such as their
capacity to behave empathically toward others. Empathy is a well-characterized, complex social behavior, involving the subjective emotional feelings induced by others’ emotions, the ability to differentiate between the feelings one experiences and the feelings expressed by others, and mental flexibility (Decety and HDAC inhibitor Jackson 2004). Inhibitors,research,lifescience,medical Despite this complexity, healthy individuals are able to represent their own level of empathy fairly accurately, indicating that this information is normally accessible to awareness. Examining the neural substrates of self-awareness for this type of complex behavioral trait could provide information to better dissociate modality-specific from supramodal neural processes underlying self-awareness. Previous neuroimaging studies have
examined impaired self-awareness independent of its directionality, despite the fact that patients can show highly divergent patterns (Michon Inhibitors,research,lifescience,medical et al. 1994; Rankin et al. 2005; Tranel et al. 2010; Zamboni et al. 2010), with some patients overestimating their level of functioning Inhibitors,research,lifescience,medical (“polishers”) and others underestimating it (“tarnishers”). Rather than reflecting a continuum, being overcritical or under critical may reflect divergent pathophysiological processes, thus this should be investigated independently. In this study, we asked whether either overestimation or underestimation of one’s capacity for empathic concern predict specific patterns of focal brain damage in a large sample of neurodegenerative disease patients and healthy older adults. To answer this question, we separated the sample into “polisher” and “tarnisher” Inhibitors,research,lifescience,medical subsamples based on the Inhibitors,research,lifescience,medical subject-informant discrepancy method, using
the Interpersonal Reactivity Index (IRI) (Davis 1983). Within each of these two subsamples, discrepancy measures were then correlated with structural MR images using voxel-based morphometry (VBM) across the whole brain. We also examined the degree to which the anatomy underlying self-awareness of empathic concern corresponds to the neural correlates of empathic concern itself and the neural correlates of affective perspective taking (Davis 1983), a cognitive capacity related Linifanib (ABT-869) to empathic concern (Davis 1983; Sollberger et al. 2012). Materials and Methods Subjects We studied 102 subjects, including 83 patients diagnosed with one of five neurodegenerative diseases and 19 healthy normal controls. Of the 83 patients, 28 patients met the research diagnostic criteria for behavioral variant frontotemporal dementia (bvFTD) (Rascovsky et al. 2011), 16 met criteria for semantic variant primary progressive aphasia (svPPA) (Gorno-Tempini et al. 2011), 4 met criteria for nonfluent variant primary progressive aphasia (nfvPPA) (Gorno-Tempini et al. 2011), 23 met criteria for AD (McKhann et al.