title: Functional neural correlates of emotional expression processing deficits in behavioural variant frontotemporal dementia.
abstract: BACKGROUND
  Frontotemporal dementia (FTD) is a neurodegenerative disorder resulting in social-cognitive deficits partially attributed to abnormalities processing social cues, such as facial expressions. However, to our knowledge, the functional neuroanatomy of deficient social cue processing in individuals with FTD has not been examined. The objective of this study was to delineate the functional abnormalities under lying altered facial expression processing in individuals with FTD using functional magnetic resonance imaging (fMRI).
  
  
  METHODS
  Patients meeting Neary criteria for behavioural variant FTD (bvFTD) with supportive neuroimaging and 18 age-matched healthy controls completed an implicit facial expression task during fMRI. We conducted volumetric brain morphometry to correct functional imaging data for volume differences.
  
  
  RESULTS
  We included 20 patients with bvFTD and 18 controls in our study. The results demonstrate emotion-specific functional abnormalities in frontal and limbic regions in patients with bvFTD. Patients also showed decreased activity in posterior ventral visual regions, specifically the fusiform cortex, possibly reflecting reduced afferent input from limbic regions. Finally, bvFTD was associated with increased activity in posterior regions, including the inferior parietal cortex.
  
  
  CONCLUSIONS
  Autopsy validation of frontotemporal dementia is not yet available for this cohort.
  
  
  CONCLUSIONS
  Together, these findings suggest that fMRI combined with tasks targeting social-cognitive deficits is a powerful technique to objectively measure neural systems involved in emotion processing in individuals with bvFTD. As viewing emotional expressions is known to engage many of the same neural systems that are active when experiencing the emotion itself, fMRI during expression processing provides a novel window into the emotions of patients with FTD.
authors.affiliation: Graduate Program in Neuroscience, University of Western Ontario, London, Ontario.
authors.forename: Karim
authors.initials: K
authors.lastname: Virani
authors.forename: Sarah
authors.initials: S
authors.lastname: Jesso
authors.forename: Andrew
authors.initials: A
authors.lastname: Kertesz
authors.forename: Derek
authors.initials: D
authors.lastname: Mitchell
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Finger
mesh_terms: D000368:Aged; D001921:Brain / Q000503:physiopathology*; D016022:Case-Control Studies; D003463:Cues; D004192:Discrimination, Psychological / Q000502:physiology; D004644:Emotions / Q000502:physiology*; D005149:Facial Expression; D005260:Female; D057180:Frontotemporal Dementia / Q000503:physiopathology / Q000523:psychology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008606:Mental Processes / Q000502:physiology; D009483:Neuropsychological Tests; D010775:Photic Stimulation; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed