Which piece of legislation granted African Americans the legal right to vote?

The 15th amendment guaranteed the right to vote to African Americans.

There's a saying in brain science based on the work of Donald Hebb: neurons that fire together, wire together. The more they fire together, the more they wire together. In essence, you develop psychological resources by having sustained and repeated experiences of them that are turned into durable changes in your brain. You become more grateful, confident, or determined by repeatedly installing experiences of gratitude, confidence, or determination. Similarly, you center yourself increasingly in the Responsive, green zone - with an underlying sense of peace, contentment, and love - by having and internalizing many experiences of safety, satisfaction, and connection.