 Rate distortion theory provides a powerful framework for understanding the nature of human memory by formalizing the relationship between information rate, the average number of bits per stimulus transmitted across the memory channel, and distortion, the cost of memory errors. Here, we show how this abstract computational level framework can be realized by a model at neural population coding. The model reproduces key regularities of visual working memory, including some that were not previously explained by population coding models. We verify a novel prediction of the model by re-analysing recordings of monkey prefrontal neurons during an ocular motor delayed response task. This article was authored by Anthony Mv Jacob and Samuel J. Gershman.