Positronic brain
Clockwork Cherubs had positronic brains. (PROSE: Lord Thymon and the Department of Problem-Solving) Juliet the 945th recovered “positronic components” from her Fog Ship to create Juliet the 1273rd. (PROSE: Acquaintanceship-982 and the Missing Mail Mystery) Studying Pessimist-242's strangely downcast disposition, “amateur researchers at the Department of Cupid Anatomy” once hypothesised that he had a negatronic brain instead of a positronic brain. The Department of Physics found this coinage “ridiculous and entirely unscientific”. (PROSE: Acquaintanceship-982 and the Missing Mail Mystery)
Behind the scenes
The positronic brain was a critical robot component in Issac Asimov's golden age science fiction tales. Being the first writer to meaningfully address robots as both characters and plausible technological items, his robot stories were highly influential on later science fiction.