Acta Neuropathologica

, Volume 116, Issue 5, pp 479–489

Selective reduction of Von Economo neuron number in agenesis of the corpus callosum

  • Jason A. Kaufman
  • Lynn K. Paul
  • Kebreten F. Manaye
  • Andrea E. Granstedt
  • Patrick R. Hof
  • Atiya Y. Hakeem
  • John M. Allman
Original Paper

DOI: 10.1007/s00401-008-0434-7

Cite this article as:
Kaufman, J.A., Paul, L.K., Manaye, K.F. et al. Acta Neuropathol (2008) 116: 479. doi:10.1007/s00401-008-0434-7

Abstract

Von Economo neurons (VENs) are large spindle-shaped neurons localized to anterior cingulate cortex (ACC) and fronto-insular cortex (FI). VENs appear late in development in humans, are a recent phylogenetic specialization, and are selectively destroyed in frontotemporal dementia, a disease which profoundly disrupts social functioning and self-awareness. Agenesis of the corpus callosum (AgCC) is a congenital disorder that can have significant effects on social and emotional behaviors, including alexithymia, difficulty intuiting the emotional states of others, and deficits in self- and social-awareness that can impair humor, comprehension of non-literal or affective language, and social judgment. To test the hypothesis that VEN number is selectively reduced in AgCC, we used stereology to obtain unbiased estimates of total neuron number and VEN number in postmortem brain specimens of four normal adult controls, two adults with isolated callosal dysgenesis, and one adult whose corpus callosum and ACC were severely atrophied due to a non-fatal cerebral arterial infarction. The partial agenesis case had approximately half as many VENs as did the four normal controls, both in ACC and FI. In the complete agenesis case the VENs were almost entirely absent. The percentage of neurons in FI that are VENs was reduced in callosal agenesis, but was actually slightly above normal in the stroke patient. These results indicate that the VEN population is selectively reduced in AgCC, but that the VENs do not depend on having an intact corpus callosum. We conclude that in agenesis of the corpus callosum the reduction in the number of VENs is not the direct result of the failure of this structure to develop, but may instead be another consequence of the genetic disruption that caused the agenesis. The reduction of the VEN population could help to explain some of the social and emotional deficits that are seen in this disorder.

Keywords

StereologyAnterior cingulate cortexFronto-insular cortex

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Jason A. Kaufman
    • 1
  • Lynn K. Paul
    • 2
    • 3
  • Kebreten F. Manaye
    • 4
  • Andrea E. Granstedt
    • 5
  • Patrick R. Hof
    • 6
  • Atiya Y. Hakeem
    • 1
  • John M. Allman
    • 1
  1. 1.Division of BiologyCalifornia Institute of TechnologyPasadenaUSA
  2. 2.Division of Humanities and Social SciencesCalifornia Institute of TechnologyPasadenaUSA
  3. 3.Graduate School of PsychologyFuller Theological SeminaryPasadenaUSA
  4. 4.Department of Physiology and BiophysicsHoward University College of MedicineWashington, DCUSA
  5. 5.Department of Molecular BiologyPrinceton UniversityPrincetonUSA
  6. 6.Department of NeuroscienceMount Sinai School of MedicineNew YorkUSA