title: Representing the forest before the trees: a global advantage effect in monkey inferotemporal cortex.
abstract: Hierarchical stimuli (large shapes composed of small shapes) have long been used to study how humans perceive the global and the local content of a scene--the forest and the trees. Studies using these stimuli have revealed a global advantage effect: humans consistently report global shape faster than local shape. The neuronal underpinnings of this effect remain unclear. Here we demonstrate a correlate and possible mechanism in monkey inferotemporal cortex (IT). Inferotemporal neurons signal the global content of a hierarchical display approximately 30 ms before they signal its local content. This is a specific expression of a general principle, related to spatial scale or spatial frequency rather than to hierarchical level, whereby the representation of a large shape develops in IT before that of a small shape. These findings provide support for a coarse-to-fine model of visual scene representation.
authors.affiliation: Center for Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA. sparun@cnbc.cmu.edu
authors.forename: Arun P
authors.initials: AP
authors.lastname: Sripati
authors.forename: Carl R
authors.initials: CR
authors.lastname: Olson
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000704:Analysis of Variance; D000818:Animals; D005260:Female; D006801:Humans; D008253:Macaca mulatta; D008297:Male; D009474:Neurons / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011930:Reaction Time / Q000502:physiology; D012858:Size Perception / Q000502:physiology*; D013223:Statistics as Topic; D013702:Temporal Lobe / Q000166:cytology / Q000502:physiology*; D013997:Time Factors; D014795:Visual Pathways / Q000502:physiology