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O2‐10‐02: Atrophy in distinct corticolimbic networks subserving social‐affective behavior in semantic‐variant primary progressive aphasia
Author(s) -
Perez David L.,
Makaretz Sara,
Caso Christina,
Stepanovic Michael,
Brickhouse Michael,
Quimby Megan,
Hochberg Daisy,
Xia Chenjie,
Dickerson Bradford C.
Publication year - 2015
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1016/j.jalz.2015.07.184
Subject(s) - primary progressive aphasia , psychology , insula , entorhinal cortex , orbitofrontal cortex , atrophy , superior temporal sulcus , audiology , frontotemporal dementia , anterior cingulate cortex , neuroscience , functional magnetic resonance imaging , dementia , hippocampus , medicine , prefrontal cortex , cognition , disease
OBJECTIVE : Semantic-variant Primary Progressive Aphasia(svPPA) is a neurodegenerative disorder with core impairments in semantic memory. Although many svPPA patients also exhibit symptoms involving social-emotional behavior, these have received relatively little study. We investigated atrophy in large-scale brain networks subserving social-emotional behaviors in svPPA compared to controls. BACKGROUND : We previously defined three social-emotional brain networks in healthy subjects. The perception network guiding detection/interpretation of social sensory cues includes the fusiform gyrus, ventral temporal pole, superior temporal sulcus and lateral orbitofrontal cortex. The affiliation network facilitating prosocial behaviors includes the ventromedial prefrontal, subgenual and rostral anterior cingulate cortices, dorsal temporal pole, hippocampus, parahippocampus, entorhinal cortex and nucleus accumbens. The aversion network mediating avoidant behaviors includes the insula, caudal anterior cingulate cortex and putamen. These networks are linked to amygdalar subregions. We hypothesized that these three networks would exhibit atrophy in svPPA and relate to socioemotional impairment. DESIGN/METHODS : Seventeen svPPA subjects and thirty age-and-gender matched controls were studied. T1-weighted MPRAGE MRI scans were acquired, and FreeSurfer software was used to process data and extract cortical thickness or volumetric data across a priori regions-of-interest. Findings were statistically significant at p≤0.005 to correct for multiple comparisons. The types and severity of social symptoms were rated using the Social Impairment Rating Scale (SIRS). RESULTS : svPPA subjects showed left-lateralized perception(z-score=-4.729; p<0.0001) and affiliation(z-score=-3.483; p=0.0005) network atrophy. Trends toward bilateral amygdala and right perception network atrophy were also observed. Left affiliation network atrophy correlated with SIRS socioemotional detachment sub-scores(r=0.56; p=0.037). The aversion network and control networks (mentalizing and mirror networks) did not show statistically significant atrophy. CONCLUSIONS : svPPA patients demonstrated left-lateralized perception and affiliation network atrophy which may provide the biological basis for social-emotional deficits in these patients. Future symptom-specific analyses may further clarify these brain-behavior relationships.Study Supported by: R21 NS077059, R21 MH097094, and R25 NS065743-05S1. Disclosure: Dr. Perez has nothing to disclose. Dr. Makaretz has nothing to disclose. Dr. Caso has nothing to disclose. Dr. Stepanovic has nothing to disclose. Dr. Brickhouse has nothing to disclose. Dr. Quimby has nothing to disclose. Dr. Hochberg has nothing to disclose. Dr. Xia has nothing to disclose. Dr. Dickerson has received personal compensation for activities with Pfizer, Inc., En Vivo, and Merck.