Artificial intelligence · 1990
Recurrent neural networks
Networks with loops carry memory forward to process sequences like language.
Jeffrey Elman's simple recurrent network fed hidden state back as input, learning grammatical structure from word sequences. Trained by backpropagation through time, RNNs became the default for speech and text until transformers, though they struggled to remember far back.
What it built on 2
What it led to 1
Related measurements
The dashed line marks when it first worked.
Training compute of notable AI models Source: Epoch AI, Notable AI Models (CC BY 4.0)
Computation per constant dollar, 1850-2006 Latest: 7.3B million units of computer power per 2006 $ (2003) Source: Nordhaus 2007, Two Centuries of Productivity Growth in Computing, J. Econ. Hist. 67(1), Table 6