The laboratory

The Groschner lab studies signal processing in the brain. We use the fruit fly as a model in which
numerical simplicity, well-charted connectivity, and our ability to control nervous activity have
aligned to make mechanistic ideas precise and testable. Our work is based on the premise that
nervous systems across species employ a common set of circuit architectures to perform certain
core computations. Bridging biophysics and behaviour, we describe these circuits in molecular
detail and search for general principles of how they operate. [1-4]

The project

How does a brain construct a memory that is stable during times of immobility, but exquisitely
malleable—sensitive to every step—during locomotion? When moving about, animals keep track
of their current speed and heading in allocentric coordinates [5]. Temporal integration of these
momentary travel vectors allows insects to generate and maintain a mental representation of
the shortest route to the point of origin. We want to find out how the brain encodes the length
of such a vector.

The project relies on behavioural assays and manipulations of neural activity in vivo. The
sucessful candidate will use optogenetics to instill a sense of distance into the fly brain and
screen transgenic fly lines to discover the neurons involved in this type of memory. The project
is expected to last five to six months.

Equality, diversity & inclusion

The Groschner lab strives to foster an environment that welcomes, includes, and values people
with diverse backgrounds and experiences. We provide all student with the support, space, and
resources they need to pursue their goals and further their careers.

References

References
1. Borst & Groschner (2023) How flies see motion. Annu. Rev. Neurosci. 46: 17-37.
2. Groschner et al. (2022) A biophysical account of multiplication by a single neuron. Nature 603: 119-123.
3. Groschner & Miesenböck (2019) Mechanisms of sensory discrimination: insights from Drosophila olfaction. Annu. Rev.
Biophys. 48: 209-229.
4. Groschner et al. (2018) Dendritic integration of sensory evidence in perceptual decision-making. Cell 173: 894-905.
5. Lyu et al. (2021) Building an allocentric travelling direction signal via vector computation. Nature 601: 92-97.