Research - A System Oriented Approach

Significant progress has been made in the field of cellular and molecular neuroscience. Modern in-vivo imaging techniques have revolutionized non-invasive observation of brain activity even in humans. Today's challenge lies in understanding the brain as a complex and functioning system.
For example: we still cannot explain how information, processed in parallel pathways within one sensory modality, is fused into the complex object we perceive, as a face or a specific voice.

The following typical research topics will serve as interdisciplinary links within system oriented neurosciences:

The biology of information processing: links from single cells to complex circuits

One of the major challenges in the contemporary neurosciences is the transfer of the increasingly detailed knowledge of cellular processes onto more complex functional, and systemic levels. The auditory system provides an ideal example of such a transition, because it is characterized by a rather unique structure-function relationship of neural arrangements as well as the clear segregation into different anatomical and functional, parallel pathways. In general, acoustic cues carry a multitude of information in the temporal domain and, therefore, the rules and mechanisms underlying the processing of such temporal information can be particularly well studied in the auditory brainstem.

Links from system analysis to mathematical modeling

The quantitative analysis of a biological system is not possible without first constructing a simple algorithmic model. A model can provide important insights into the structure of a system, and it does increase the understanding of the system itself. Modeling can also reveal the logical errors of simple biological and clinical concepts. Moreover, to be able to simulate the complete or incomplete failure of a single element or an entire pathway permits us to pose direct clinical questions in Neurology and Neurosurgery about the localization of the damage as well as the mechanism involved.

Links from perception and cognition to mind and neurophilosophy

"Humans can do more than reflexively react to sensory information that is immediate and salient. We engage in complex and extended behaviours geared towards often far-removed goals. To do so, we have evolved mechanisms that can override or augment reflexive and habitual reactions in order to orchestrate behaviour in accordance with our intentions. These mechanisms are commonly referred to as 'cognitive' in nature and their function is to control lower level sensory, memory and/or motor operations for a common purpose" (E. Miller). How cognitive control regulates the information flow from perception to action while allowing it to be governed by current intentions is a major theme of Neurocognitive Psychology.

From Model to Patient - decoding molecular mechanisms of neurodegenerative and psychiatric disease

A complex network of different neuronal populations, their neurotransmitters as well as cerebral endocrine glands and hormones build the basis for major brain and body functions and behaviours. Their disturbance leads to the development of severe human neurological and psychiatric disorders. Using conventional (knock-outs and knock-ins) and conditional mutagenic approaches in mice complemented by a wide array of morphological, histological, molecular/cell biological, biochemical, behavioural and even bioinformatical analyses, we try to understand the physiology, the molecular mechanisms and genetic networks underlying neurogenerative and psychiatric illnesses such as Parkinson's disease and depression. This combined knowledge may aid in devising new therapeutic strategies for these disorders based on regenerative and/or stem cell-based approaches.

Links from biology to technical solutions

As biological and technical systems are governed by closely related physical laws, their sensorimotor control mechanisms are similar. The biological principles that have evolved over millions of years continue to serve as inspiration for new technical solutions. Here the human ocular motor system is exemplary. Visual exploration is made possible by the use of voluntary saccades, when the eyes are quickly moved from one visual target to another, and voluntary smooth pursuit, when the eyes follow a moving target.

The vestibulo-ocular reflex relies on inner ear sensors that signal both linear accelerations and angular head velocities to the brain. This velocity information is transformed mathematically by integration into a positional signal, which is then inverted and delivered to the eye muscles. During head movements, the biological reflex moves the eyes in their orbits in the opposite direction to the head motion, thus ensuring a stable projection of the visual scene onto the retina. A similar mechanism becomes active when large-field visual stimuli are moved in front of an observer (optokinetic reflex).
Neurologists and engineers have together developed a new camera system for surgeons, which looks where the eyes look.