Tool-use learning induces BDNF expression in a selective portion of monkey anterior parietal cortex.

Learning but not execution of tool-use induced expression of brain-derived neurotrophic factor (BDNF). The expression was highest in the anterior bank of the intraparietal sulcus, especially in the region posteriorly adjacent to the somatosensory shoulder and forearm region in area 3b, suggesting that BDNF plays a role in altering the body image of the hand to include the repeatedly used tool as its extension.