We discuss models for computation in biological neural systems that are bas
ed on the current stare of knowledge in neurophysiology. Differences and si
milarities to traditional neural network models are highlighted. It turns o
ut that many important questions regarding computation and learning in biol
ogical neural systems cannot be adequately addressed in traditional neural
network models. In particular, the role of time is quite different in biolo
gically more realistic models, and many fundamental questions regarding com
putation and learning have to be rethought for this context. Simultaneously
, a somewhat related new generation of VLSI-chips is emerging ("pulsed VLSI
") where new ideas about computing and learning with temporal coding can be
tested in an engineering context. Articles with details to models and resu
lts that are sketched in this article can be found at http://www.tu-graz.ac
.at/igi/maass/. We refer to Maass and Bishop (Eds., Pulsed Neural Network.
MIT Press, Cambridge, MA. 1999) for a collection of survey articles that co
ntain further details and references. (C) 2001 Elsevier Science B.V. All ri
ghts reserved.