Fig. 6: Schematic highlighting the essential role of dopaminergic inputs from the VTA to M1 in motor learning.

During training for a hand-reach task, the beginner M1 layer 2-3 network (light blue) reorganizes into an expert configuration (dark blue), while the overall network connectivity (represented by the number of edges) remains unchanged. Dopaminergic inputs from the VTA to M1 are essential for both motor learning and the transformation of the network into the expert configuration. Figure credit to Dafna Antes.