Team

Arrenberg Lab, August 2019

If you’re interested in joining the group as a postdoc, or for a doctoral thesis or student project, please contact Aristides Arrenberg.

Aristides Arrenberg

+49 (0)7071 29 88798
I studied biochemistry and neuroscience at the University of Hamburg and the University of California San Francisco (UCSF). During my doctoral thesis at UCSF (2005-2010), I implemented and characterized optogenetic tools in zebrafish and used them to study visual, oculomotor and cardiovascular function. Oftentimes it is necessary to develop new experimental tools before being able to answer biological questions, as the community of zebrafish systems neuroscientists is young and growing. During my postdoctoral time at the University of Freiburg I set up a two-photon-microscope and used it to investigate the role of a specific population of dopaminergic neurons in locomotion. At the University of Tübingen, my laboratory continues to work on vision and oculomotor circuits and furthermore started to study the ecological adaptations of the zebrafish brain to its habitat and behavior.   

Florian Dehmelt
Postdoc
As a physicist and biologist, I’m interested in understanding how constraints and perturbations shape neural network dynamics. To provide a reality-check on previous spiking network simulations, I was drawn towards the reflexive oculomotor behaviours of zebrafish larvae, and the concurrent imaging of neural activity. At Arrenberg lab, my current focus is on data analysis, visualisation and methods development. Using a spherical, nearly full-field visual stimulation arena, we were able to demonstrate the anisotropic dependence of OKR on stimulus location and its relation to the anisotropic retinal photoreceptor density (Dehmelt, Meier, Hinz et al., in preparation). We are always happy to share our methods and setups with the zebrafish community, and have published mostly open-source eyetracking solutions (Dehmelt et al. 2018 Nature Protocols). I’ve also had the opportunity to contribute to refinement studies in lab animal science, including zebrafish anaesthesia (Leyden et al., unpublished). Both within and outside the lab, I’m passionate about science outreach and communications. 

Christian Brysch
PhD student
I got my Bachelor’s and Master’s degree in Biology from the Technical University Munich. I joined the Arrenberg-Lab initially in Freiburg and then moved with the lab to the CIN in Tübingen. In my project, I use 2 Photon-Calcium imaging to investigate the neuronal integration of eye velocity in the zebrafish hindbrain that helps in retinal image stabilization. The structure responsible for that (the neural  integrator for horizontal eye movements) transforms a transient eye velocity input into a persistent eye position output, which is in turn relayed to the motoneurons to keep the eyes stable. Understanding this mechanism and the structures involved will help us to elucidate the formation of short-term memory and how it is formed.  

Claire Leyden
PhD student

My PhD focuses on the zebrafish oculomotor system. I am interested in how eye movements, and saccadic eye movements in particular, are encoded. I would also like to understand how right and left eye are coordinated, and what is happening when the eyes are unyoked and moving somewhat independent of each other. In my research I carry out behavioural experiments usually in combination with two photon calcium imaging which allows me to probe the relationships between neural activity and behaviour.  

Kun Wang
PhD student
My PhD project focuses mainly on the optic flow encoding in the larval zebrafish visual system. Zebrafish can perceive and differentiate rotational and translational whole field motion and initiate optokinetic or optomotor responses to maintain external images in the retina or body position. One main goal of my research is to identify the sensory neurons specifically representing whole filed binocular visual stimuli. These neurons are likely to send outputs to the (pre-)motor neurons to initiate final behavioral outputs. Meanwhile, whole field optic flow and local motion are mainly detected by neurons which extract different size features. To understand the encoding of optic flow, characterizing visual receptive fields of the neurons in zebrafish brain is another major topic for us.  

Yue Zhang
PhD student
How many neurons will a person need, to breathe and feel and suffer and love? If we find a brain has just enough neurons for “love”, will we learn more about the essence of love by thoroughly studying the functions of each neuron in the brain? 
I’m developing a noise-robust receptive field estimation method that can characterize the functions of hundreds of neurons within less than an hour. Using this systematic functional characterization method, I’d first like to investigate the visual motion information processing in the larval zebrafish brain with 2-photon calcium imaging. I’m curious to know if such a systematic approach could lead us closer to the essence of, not love, but visual motion perception. Because after all, love is such a complicated thing. 

Tim Hladnik
PhD student
I obtained my bachelor’s degree in biology studying the jamming behavior of wave-type weakly-electric fish and my master’s degree in neurobiology about the neuronal encoding of their electric fields. My current focus of study is on how the visuomotor systems of zebrafish and african cichlids are adapted to the statistics of their natural habitats and how these adaptations differ based on their respective habitats and innate behaviors. I am currently working on constructing a visual display setup that will allow us to faithfully display naturalistic, multi-color movies to fish while using 2-photon calcium imaging to record whole-brain activity in the visual system. 

Other Lab Members

Nina Omejc – MSc Student
Wiebke Nörenberg – MSc Student
Bild Julia Fechner
Julia Fechner – Student Assistant
Florentyna Debinsky – BSc Student
Timo Brüggemann – MSc Student
Sabrina Fuchs – Scientist
Maximilian Wandl, Student Assistant

Punting on the Neckar river