Functional asymmetries in early learning during right, left, and bimanual performance in right-handed subjects.
OBJECTIVE
To elucidate differences in activity and connectivity during early learning due to the performing hand.


METHODS
Twenty right-handed subjects were recruited. The neural correlates of explicit visuospatial learning executed with the right, the left hand, and bimanually were investigated using functional magnetic resonance imaging. Connectivity analyses were carried out using the psychophysiological interactions model, considering right and left anterior putamen as index regions.


RESULTS
A common neural network was found for the three tasks during learning. Main activity increases were located in posterior cingulate cortex, supplementary motor area, parietal cortex, anterior putamen, and cerebellum (IV-V), whereas activity decrements were observed in prefrontal regions. However, the left hand task showed a greater recruitment of left hippocampal areas when compared with the other tasks. In addition, enhanced connectivity between the right anterior putamen and motor cortical and cerebellar regions was found for the left hand when compared with the right hand task.


CONCLUSIONS
An additional recruitment of brain regions and increased striato-cortical and striato-cerebellar functional connections is needed when early learning is performed with the nondominant hand. In addition, access to brain resources during learning may be directed by the dominant hand in the bimanual task.
Functional Neuroimaging Laboratory, Division of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain.
Maite
M
Aznárez-Sanado
Maria A
MA
Fernández-Seara
Francis R
FR
Loayza
Maria A
MA
Pastor
D000328:Adult; D001519:Behavior; D001921:Brain / Q000473:pathology; D001931:Brain Mapping / Q000379:methods; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007858:Learning; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008960:Models, Psychological; D009048:Motor Skills; D011597:Psychomotor Performance / Q000502:physiology; D011699:Putamen / Q000473:pathology* / Q000502:physiology; D055815:Young Adult