title: A distributed left hemisphere network active during planning of everyday tool use skills.
abstract: Determining the relationship between mechanisms involved in action planning and/or execution is critical to understanding the neural bases of skilled behaviors, including tool use. Here we report findings from two fMRI studies of healthy, right-handed adults in which an event-related design was used to distinguish regions involved in planning (i.e. identifying, retrieving and preparing actions associated with a familiar tools' uses) versus executing tool use gestures with the dominant right (experiment 1) and non-dominant left (experiment 2) hands. For either limb, planning tool use actions activates a distributed network in the left cerebral hemisphere consisting of: (i) posterior superior temporal sulcus, along with proximal regions of the middle and superior temporal gyri; (ii) inferior frontal and ventral premotor cortices; (iii) two distinct parietal areas, one located in the anterior supramarginal gyrus (SMG) and another in posterior SMG and angular gyrus; and (iv) dorsolateral prefrontal cortex (DLFPC). With the exception of left DLFPC, adjacent and partially overlapping sub-regions of left parietal, frontal and temporal cortex are also engaged during action execution. We suggest that this left lateralized network constitutes a neural substrate for the interaction of semantic and motoric representations upon which meaningful skills depend.
authors.affiliation: Department of Psychology, University of Oregon, Eugene, OR 97403-1227, USA. shfrey@darkwing.uoregon.edu
authors.forename: Scott H
authors.initials: SH
authors.lastname: Johnson-Frey
authors.forename: Roger
authors.initials: R
authors.lastname: Newman-Norlund
authors.forename: Scott T
authors.initials: ST
authors.lastname: Grafton
mesh_terms: D000328:Adult; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D004292:Dominance, Cerebral / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009048:Motor Skills / Q000502:physiology*; D010296:Parietal Lobe / Q000502:physiology; D013702:Temporal Lobe / Q000502:physiology