Red Means Go! The red shows the activated brain areas in London taxi drivers as they navigated the busy London streets. Not only were these areas more active than the same areas in the average person’s brain, but they also had more dendrites. In addition, the longer a cabby had been driving, the more brain growth was evident. This research confirms plasticity, implying that we all could develop new skills, not only by remembering but also by engaging in activities that change the very structures of our brains.