Learning about rhythm, pitch, and melody for 20 days increased preschoolers' verbal-intelligence scores by an average of about 20%, with more than 90% of the children showing improvement, according to a study led by Sylvain Moreno of the Rotman Research Institute in Toronto. Music and language appear to be closely linked in the brain: The processing of music may overlap with mechanisms for handling other cognitive activities, the researchers say. A comparable training program in visual art yielded no improvement in verbal intelligence.

Source: Short-Term Music Training Enhances Verbal Intelligence and Executive Function