feedforward neural networks recurrent neural networks Wilhelm Lenz Ernst Ising Ising model Shun'ichi Amari John Hopfield speech recognition language processing Hopfield feedforward neural network
There are two types of neural networks: feedforward neural networks (FNNs) and recurrent neural networks (RNNs). RNNs have cycles in their connectivity structure, FNNs don't. In the 1920s, Wilhelm Lenz and Ernst Ising created and analyzed the Ising model which is essentially a non-learning RNN architecture consisting of neuron-like threshold elements. In 1972, Shun'ichi Amari made this architecture adaptive. His learning RNN was popularised by John Hopfield in 1982. RNNs have become central for speech recognition and language processing.
