Max Planck Institute for Neurobiology of Behavior - caesar

When predatory mammals chase prey saccades align the retina to world motion and not the actual thing they are chasing

With twelve Synergy Grants, the Max Planck Society claims top spot in the ERC ranking

Ghost channels explain transient behaviors of complex systems like climate processes or neuronal networks

The scientists and their research teams receive around 40 million euros in funding for their work

Worms provide new insights into evolution and diversity of the TGF-beta signaling pathway

Magnetic fields have no smell or taste, they are invisible, and they do not make any noise. As a result, we humans are not able to sense them on our own. The African mole-rat, on the other hand, has a magnetic sense or magnetoreception that it uses to find its way in the darkness. Pascal Malkemper and his team at the Max Planck Institute for Neurobiology of Behavior – caesar in Bonn are studying how this subterranean rodent senses magnetic fields.

African mole-rats spend their entire life in underground tunnel systems that can extend over several kilometers. Despite absolute darkness mole-rats navigate within these mazes with utmost efficiency. They are guided by the rare sensory ability to use the Earth’s magnetic field for orientation. We aim to understand the structure of the receptors of the magnetic sense and how magnetic cues are processed in the mole-rat brain.

To navigate, animals must stabilize their path against disturbances and change direction e.g. to avoid obstacles. We study the neural circuits and mechanisms underlying such steering maneuvers by simultaneously recording behavioral and neuronal activity in tethered flying fruit flies Drosophila. Thus, we identified a descending neuron, whose activity strongly correlates with turning behavior during flight and appears sufficient to elicit steering behavior.

Amongst mammalian species, the diameter of the eye varies by more than an order of magnitude. Objects in visual space traverse the surface of the retina of a large diameter eye at a higher velocity than that of a small diameter eye, raising the question of how different species encode the velocity of moving objects. Using comparative connectomics and computational modelling, we identified a difference in the placement of synapses among neurons in the mouse versus rabbit retina. Our results suggest an adaptation in neural wiring that compensates for eye diameter differences across species.

How are decisions formed in the brain? Investigations on the rat nervous system show that the basic principles of such complex processes can be studied on detailed models of neuronal networks. Novel techniques allow reconstructing the structure of neurons after having studied their function in living animals. By means of these data, models of entire brain areas can be created. By simulating neuronal activity patterns in these anatomically detailed network models, scientists hope to gain insight into how sensory information and behaviors that arise from it are encoded in the brain.

How do the networks in the brain enable navigation and how do they control movements? Addressing these questions in the simple nervous system of the fruit fly indicates that basic network structures that are relevant for the mammalian brain contribute to navigation behavior in the fly. Thanks to the small size of the fly brain and the available genetic tools these networks can be analyzed in detail. Such experiments are expected to contribute to our understanding of how abstract computations are encoded in biological networks.