Neuroanatomy of pseudobulbar affect : a quantitative MRI study in multiple sclerosis

J Neurol. 2008 Mar;255(3):406-12. doi: 10.1007/s00415-008-0685-1. Epub 2008 Feb 26.


Pseudobulbar affect (PBA) is defined as episodes of involuntary crying, laughing, or both in the absence of a matching subjective mood state. This neuropsychiatric syndrome can be found in a number of neurological disorders including multiple sclerosis (MS). The aim of this study was to identify neuroanatomical correlates of PBA in multiple sclerosis (MS) using a case-control 1.5T MRI study. MS patients with (n = 14) and without (n = 14) PBA were matched on demographic, disease course, and disability variables. Comorbid psychiatric disorders including depressive and anxiety disorders were absent. Hypo- and hyperintense lesion volumes plus measurements of atrophy were obtained and localized anatomically according to parcellated brain regions. Between-group statistical comparisons were undertaken with alpha set at 0.01 for the primary analysis. Discrete differences in lesion volume were noted in six regions: Brainstem hypointense lesions, bilateral inferior parietal and medial inferior frontal hyperintense lesions, and right medial superior frontal hyperintense lesions were all significantly higher in the PBA group. A logistic regression model identified four of these variables (brainstem hypointense, left inferior parietal hyperintense, and left and right medial inferior frontal hyperintense lesion volumes) that accounted for 70% of the variance when it came to explaining the presence of PBA. In conclusion, MS patients with PBA have a distinct distribution of brain lesions when compared to a matched MS sample without PBA. The lesion data support a widely-dispersed neural network involving frontal, parietal, and brainstem regions in the pathophysiology of PBA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Affective Symptoms / etiology
  • Affective Symptoms / psychology*
  • Atrophy
  • Brain / pathology
  • Case-Control Studies
  • Expressed Emotion
  • Female
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Multiple Sclerosis / complications
  • Multiple Sclerosis / pathology*
  • Multiple Sclerosis / psychology
  • Prognosis