How does thinking work? How do we interpret what we see, hear, smell, and touch? – and how do we decide what
we do and how we do it in the world around us? This – I believe – is one of today's greatest mysteries in science.
Looking at small animals with tiny brains, we get the impression that they act effortlessly in the world,
foraging for food and returning home safely. In contrast, today's carefully hand-designed computers and robots
with all available sensors and processing power are hardly able to successfully perform such simple behaviors.
The world is too complex and too ambiguous to get interpreted reliably with contemporary algorithms. So in
which fundamental principles does information processing in brains differ from information processing performed
by current computing algorithms?
Probably the most fundamental difference is already established by the design of the elementary unit that
performs computation: today’s engineered systems typically rely on relatively few but powerful and cautiously
hand-designed processing cores (CPUs) – even high-end machines typically have no more than four CPUs in a system.
Brains, in contrast, are composed of a large number of relatively simple processing units (neurons) – ranging in
count from a few hundred in the simplest worms up to several 1011 neurons in a mammalian brain. Each such neuron
operates with relatively low speed, but all of them work in parallel, forming a large, self-grown, recurrently
interconnected network of “computing machines”, each contributing to the overall task. No neuron – and no group
of neurons – has access to global information, as CPUs do in our computers.
This difference in computing hardware imposes severe constraints for computing algorithms, that today to a
large extent are completely unaddressed. How can a distributed system with only local knowledge perform globally
consistent actions? How does such a system build itself – starting from a nucleus – with only local knowledge and
no global supervisor? Why is such a large network of neurons relatively insensitive to changes in the connectivity
pattern and to defective computing units? How does such a deep network learn?
In my research I am addressing such questions by applying neuronal-style algorithmic primitives to artificial
engineered systems that interact intelligently with the real world – thereby working towards understanding how
brains perform computation, and ultimately gaining insight in why such systems outperform contemporary algorithms.
This page shows past and current research projects, highlighting how I apply principles from neuronal information
processing to engineering problems.
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