Long-lasting cortical plasticity in the object naming system.
A single exposure to an object can produce long-lasting behavioral change. Here, using event-related functional magnetic resonance imaging (fMRI), we provide evidence for long-lasting changes in cortical activity associated with perceiving and naming objects. In posterior regions, we observed an immediate (30-second) and long-lasting (3-day) decrease in neural activity after brief (200-ms) exposure to nameable and nonsense objects. In addition, slower-developing decreases in left inferior frontal activity were observed concurrently with increases in left insula activity, only for nameable objects. These time-dependent cortical changes may reflect two distinct learning mechanisms: the formation of sparser, yet more object-form-specific, representations in posterior regions, and experience-induced reorganization of the brain circuitry underlying lexical retrieval in anterior regions.
van Turennout
M
M
Laboratory of Brain and Cognition, National Institute of Mental Health, Building 10, Room 4C104, 10 Center Drive MSC 1366, Bethesda, Maryland 20892-1366, USA. Miranda.VanTurennout@mpi.nl
Ellmore
T
T
Martin
A
A
D002540:Cerebral Cortex / Q000033:anatomy & histology / Q000502:physiology*; D005625:Frontal Lobe / Q000033:anatomy & histology / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000502:physiology; D009483:Neuropsychological Tests; D009778:Occipital Lobe / Q000033:anatomy & histology / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000502:physiology; D014705:Verbal Behavior / Q000502:physiology*