Learning to solve the credit assignment problem

Understand

Backpropagation is driving today's artificial neural networks (ANNs).

• However, despite extensive research, it remains unclear if the brain implements this algorithm.
• Among neuroscientists, reinforcement learning (RL) algorithms are often seen as a realistic alternative: neurons can randomly introduce change, and use unspecific feedback signals to observe their effect on the cost and thus approximate their gradient.
• However, the convergence rate of such learning scales poorly with the number of involved neurons.