Regional dendritic and spine variation in human cerebral cortex: a quantitative Golgi study

B. Jacobs et al., Regional dendritic and spine variation in human cerebral cortex: a quantitative Golgi study, CEREB CORT, 11(6), 2001, pp. 558-571
Citations number
Categorie Soggetti
Neurosciences & Behavoir
Journal title
ISSN journal
1047-3211 → ACNP
Year of publication
558 - 571
SICI code
The present study explored differences in dendritic/spine extent across sev eral human cortical regions. Specifically, the basilar dendrites/spines of supragranular pyramidal cells were examined in eight Brodmann's areas (BA) arranged according to Benson's functional hierarchy: primary cortex (somato sensory, BA3-1-2; motor, BA4), unimodal cortex (Wernicke's area, BA22: Broc a's area, BA44), heteromodal cortex (supplementary motor area, BA6 beta; an gular gyrus, BA39) and supramodal cortex (superior frontopolar zone, BA10; inferior frontopolar zone, BA11), To capture more general aspects of region al variability, primary and unimodal areas were designated as low integrati ve regions: heteromodal and supramodal areas were designated as high integr ative regions. Tissue was obtained from the left hemisphere of 10 neurologi cally normal individuals (M-ago = 30 +/- 17 years; five males, five females ) and stained with a modified rapid Golgi technique. Ten neurons were sampl ed from each cortical region (n = 800) and evaluated according to total den dritic length, mean segment length, dendritic segment count, dendritic spin e number and dendritic spine density. Despite considerable inter-individual variation, there were significant differences across the eight Brodmann's areas and between the high and low integrative regions for all dendritic an d spine measures. Dendritic systems in primary and unimodal regions were co nsistently less complex than in heteromodal and supramodal areas. The range within these rankings was substantial, with total dendritic length in BA10 being 31% greater than that in BA3-1-2, and dendritic spins number being 6 9% greater. These findings demonstrate that cortical regions involved in th e early stages of processing (e.g. primary sensory areas) generally exhibit less complex dendritic/spine systems than those regions involved in the la ter stages of information processing (e.g, prefrontal cortex). This dendrit ic progression appears to reflect significant differences in the nature of cortical processing, with spine-dense neurons at hierarchically higher asso ciation levels integrating a broader range of synaptic input than those at lower cortical levels.