title: Visual activation in prefrontal cortex is stronger in monkeys than in humans.
abstract: The prefrontal cortex supports many cognitive abilities, which humans share to some degree with monkeys. The specialized functions of the prefrontal cortex depend both on the nature of its inputs from other brain regions and on distinctive aspects of local processing. We used functional MRI to compare prefrontal activity between monkey and human subjects when they viewed identical images of objects, either intact or scrambled. Visual object-related activation of the lateral prefrontal cortex was observed in both species, but was stronger in monkeys than in humans, both in magnitude (factors 2-3) and in spatial extent (fivefold or more as a percentage of prefrontal volume). This difference was observed for two different stimulus sets, at two field strengths, and over a range of tasks. These results suggest that there may be more volitional control over visual processing in humans than in monkeys.
authors.affiliation: K. U. Leuven Medical School, B-3000 Leuven, Belgium.
authors.forename: Katrien
authors.initials: K
authors.lastname: Denys
authors.forename: Wim
authors.initials: W
authors.lastname: Vanduffel
authors.forename: Denis
authors.initials: D
authors.lastname: Fize
authors.forename: Koen
authors.initials: K
authors.lastname: Nelissen
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Sawamura
authors.forename: Svetlana
authors.initials: S
authors.lastname: Georgieva
authors.forename: Rufin
authors.initials: R
authors.lastname: Vogels
authors.forename: David
authors.initials: D
authors.lastname: Van Essen
authors.forename: Guy A
authors.initials: GA
authors.lastname: Orban
mesh_terms: D000818:Animals; D001143:Arousal / Q000502:physiology*; D001931:Brain Mapping; D005074:Evoked Potentials, Visual / Q000502:physiology*; D006801:Humans; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging; D008297:Male; D008606:Mental Processes / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology; D017397:Prefrontal Cortex / Q000502:physiology*; D012016:Reference Values; D013045:Species Specificity