publications | Artur Schneider

2025

Preprint

Mechanisms of Premotor-Motor Cortex Interactions during Goal Directed Behavior

Mansour Alyahyay, Gabriel Kalweit, Maria Kalweit, and 7 more authors

2025

Abs DOI

Deciphering the neural code underlying goal-directed behavior is a long-term mission in neuroscience. Neurons exhibiting preparation and movement-related activity are intermingled in the premotor and motor cortices, thus concealing the neural code of planned movements. We employed a combination of electrophysiology, pathway-specific optogenetics, phototagging, and inverse reinforcement learning (RL) to elucidate the role of defined neuronal subpopulations in the rat rostral and caudal forelimb areas (RFA and CFA), which correspond to the premotor and motor cortical areas. The inverse RL enabled the functional dissection of spatially intermingled neuronal subpopulations, complementing our pathway-specific optogenetic manipulations and unveiling differential functions of the preparation and movement subpopulations projecting from RFA to CFA. Our results show that the projecting preparation subpopulation suppresses movements, whereas the projecting movement subpopulation promotes actions. We found the influence of RFA on CFA to be adaptable, with the projection either inhibiting or exciting neurons in the superficial and deep CFA layers, depending on context and task phase. These complex interactions between RFA and CFA likely involve the differential recruitment of inhibitory interneurons in the CFA, which is supported by our electron microscopy analysis of the connectivity between these regions. We provide here unprecedented mechanistic insights into how the premotor and primary motor cortices are functionally and structurally interlinked with the potential to advance neuroprosthetics.
Preprint
Freilaser: Flexible Pulse Generator for Laser Control in Optogenetic Experiments

Artur Schneider and Ilka Diester

2025

Abs DOI Bib

To facilitate optogenetic experiments in neuroscience, we designed a cost-effective (<40 €) and versatile laser control system, FreiLaser, based on the Raspberry Pi Pico microcontroller running CircuitPython. FreiLaser allows precise control over various stimulation parameters for up to four lasers, utilizing both analog and digital signals. It features a user-friendly graphical interface for parameter configuration and real-time visualization, as well as an API for seamless integration with existing experimental setups. The system also includes a built-in mask controller to prevent behavioral bias by synchronizing masking LEDs with laser pulses. Validation tests confirmed that FreiLaser generates stable, temporally precise control signals, suitable for a range of stimulation patterns. The system’s flexibility, ease of use, and low cost make it an invaluable tool for researchers conducting optogenetic and behavioral studies. Our open-source design ensures accessibility and adaptability for a wide range of experimental needs.
@misc{schneider_freilaser_2024, title = {Freilaser: Flexible Pulse Generator for Laser Control in Optogenetic Experiments}, url = {https://www.ssrn.com/abstract=5022052}, doi = {10.2139/ssrn.5022052}, shorttitle = {Freilaser}, publisher = {{SSRN}}, author = {Schneider, Artur and Diester, Ilka}, year = {2025}, keywords = {R}, }

2024

Poster
FreiControl: A cost-efficient, open-source system for investigating individual strategies in decision making of rodents

Artur Schneider, Julian Graef, and Ilka Diester

2024

FENS meeting

Abs DOI Bib

Well designed behavioral experiments are vital to understand the complexities of neural coding, particularly as it becomes evident that such coding may be context-specific, highly distributed, and multiplexed. Traditional commercial solutions for behavioral setups, although available, often lack flexibility and comprehensive user control, and their high costs limit accessibility. Recognizing the necessity for rapid development and adaptability in behavioral experiments, we introduce here a novel cost-efficient, open-source system for controlling behavioral experiments that maintains the crucial aspects of reproducibility, monitoring, and control. At its core stands the Raspberry Pi Pico microcontroller (5 euro), which utilizes CircuitPython. This choice offers an accessible, easy-to-learn Python-based syntax, and supports a range of affordable hardware elements. Our system integrates effortlessly with synchronized video recording, digital and analog signal acquisition, all streamlined through user-friendly GUIs.To complement behavioral experiments with causal interrogation we designed a budget-friendly (<50 euros), modular and versatile laser-controller element for optogenetics, enabling precise control over various stimulation parameters of up to four lasers through an intuitive interface.We showcase the efficacy of our system with an implementation of a behavioral task for freely moving rats, whereby the animals have to dynamically adopt their strategy depending on the environmental state or external stimuli. Using modular and progressive training procedures, we demonstrate that rats can be proficiently trained in less than three weeks. This innovative system offers a flexible, modular approach for designing behavioral experiments, significantly reducing costs and enhancing scalability, thereby supporting a wide access to advanced experimental setups in neuroscientific research.
@misc{FENSposter2024, doi = {10.57736/FB64-017C}, url = {https://www.world-wide.org/fens-24/freicontrol-cost-efficient-open-source-741ccb4d}, author = {Schneider, Artur and Graef, Julian and Diester, Ilka}, title = {FreiControl: A cost-efficient, open-source system for investigating individual strategies in decision making of rodents}, publisher = {Science Communications World Wide}, year = {2024}, copyright = {Attribution 4.0 International (CC BY 4.0)}, note = {FENS meeting}, keywords = {Animal, P}, }
Multi-intention Inverse Q-learning for Interpretable Behavior Representation

Hao Zhu, Brice De La Crompe, Gabriel Kalweit, and 4 more authors

2024

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In advancing the understanding of natural decision-making processes, inverse reinforcement learning (IRL) methods have proven instrumental in reconstructing animal’s intentions underlying complex behaviors. Given the recent development of a continuous-time multi-intention IRL framework, there has been persistent inquiry into inferring discrete time-varying rewards with IRL. To address this challenge, we introduce the class of hierarchical inverse Q-learning (HIQL) algorithms. Through an unsupervised learning process, HIQL divides expert trajectories into multiple intention segments, and solves the IRL problem independently for each. Applying HIQL to simulated experiments and several real animal behavior datasets, our approach outperforms current benchmarks in behavior prediction and produces interpretable reward functions. Our results suggest that the intention transition dynamics underlying complex decision-making behavior is better modeled by a step function instead of a smoothly varying function. This advancement holds promise for neuroscience and cognitive science, contributing to a deeper understanding of decision-making and uncovering underlying brain mechanisms.
@article{zhu_multi-intention_2024, title = {Multi-intention Inverse Q-learning for Interpretable Behavior Representation}, url = {http://arxiv.org/abs/2311.13870}, doi = {10.48550/arXiv.2311.13870}, number = {{arXiv}:2311.13870}, publisher = {{arXiv}}, author = {Zhu, Hao and Crompe, Brice De La and Kalweit, Gabriel and Schneider, Artur and Kalweit, Maria and Diester, Ilka and Boedecker, Joschka}, date = {2024-09-10}, year = {2024}, eprinttype = {arxiv}, eprint = {2311.13870 [cs]}, keywords = {J}, dimensions = {true}, }

2023

FreiBox: A Versatile Open-Source Behavioral Setup for Investigating the Neuronal Correlates of Behavioral Flexibility via 1-Photon Imaging in Freely Moving Mice

Brice De La Crompe, Megan Schneck, Florian Steenbergen, and 2 more authors

eNeuro, Apr 2023

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To survive in a complex and changing environment, animals must adapt their behavior. This ability is called behavioral flexibility and is classically evaluated by a reversal learning paradigm. During such a paradigm, the animals adapt their behavior according to a change of the reward contingencies. To study these complex cognitive functions (from outcome evaluation to motor adaptation), we developed a versatile, low-cost, open-source platform, allowing us to investigate the neuronal correlates of behavioral flexibility with 1-photon calcium imaging. This platform consists of FreiBox, a novel low-cost Arduino behavioral setup, as well as further open-source tools, which we developed and integrated into our framework. FreiBox is controlled by a custom Python interface and integrates a new licking sensor (strain gauge lickometer) for controlling spatial licking behavioral tasks. In addition to allowing both discriminative and serial reversal learning, the Arduino can track mouse licking behavior in real time to control task events in a submillisecond timescale. To complete our setup, we also developed and validated an affordable commutator, which is crucial for recording calcium imaging with the Miniscope V4 in freely moving mice. Further, we demonstrated that FreiBox can be associated with 1-photon imaging and other open-source initiatives (e.g., Open Ephys) to form a versatile platform for exploring the neuronal substrates of licking-based behavioral flexibility in mice. The combination of the FreiBox behavioral setup and our low-cost commutator represents a highly competitive and complementary addition to the recently emerging battery of open-source initiatives.
@article{DeLaCrompe2023, title = {FreiBox: A Versatile Open-Source Behavioral Setup for Investigating the Neuronal Correlates of Behavioral Flexibility via 1-Photon Imaging in Freely Moving Mice}, volume = {10}, issn = {2373-2822}, url = {http://dx.doi.org/10.1523/eneuro.0469-22.2023}, doi = {10.1523/eneuro.0469-22.2023}, number = {4}, journal = {eNeuro}, publisher = {Society for Neuroscience}, author = {De La Crompe, Brice and Schneck, Megan and Steenbergen, Florian and Schneider, Artur and Diester, Ilka}, year = {2023}, month = apr, pages = {ENEURO.0469--22.2023}, keywords = {Animal, J}, dimensions = {true}, }

2022

3D pose estimation enables virtual head fixation in freely moving rats

Artur Schneider, Christian Zimmermann, Mansour Alyahyay, and 3 more authors

Neuron, Jul 2022

Abs DOI Bib

The impact of spontaneous movements on neuronal activity has created the need to quantify behavior. We present a versatile framework to directly capture the 3D motion of freely definable body points in a marker-free manner with high precision and reliability. Combining the tracking with neural recordings revealed multiplexing of information in the motor cortex neurons of freely moving rats. By integrating multiple behavioral variables into a model of the neural response, we derived a virtual head fixation for which the influence of specific body movements was removed. This strategy enabled us to analyze the behavior of interest (e.g., front paw movements). Thus, we unveiled an unexpectedly large fraction of neurons in the motor cortex with tuning to the paw movements, which was previously masked by body posture tuning. Once established, our framework can be efficiently applied to large datasets while minimizing the experimental workload caused by animal training and manual labeling.
@article{Schneider2022, title = {3D pose estimation enables virtual head fixation in freely moving rats}, volume = {110}, issn = {0896-6273}, url = {http://dx.doi.org/10.1016/j.neuron.2022.04.019}, doi = {10.1016/j.neuron.2022.04.019}, number = {13}, journal = {Neuron}, publisher = {Elsevier BV}, author = {Schneider, Artur and Zimmermann, Christian and Alyahyay, Mansour and Steenbergen, Florian and Brox, Thomas and Diester, Ilka}, year = {2022}, month = jul, pages = {2080--2093.e10}, keywords = {Animal, J}, dimensions = {true}, }
Multichannel optogenetics combined with laminar recordings for ultra-controlled neuronal interrogation

David Eriksson, Artur Schneider, Anupriya Thirumalai, and 5 more authors

Nature Communications, Feb 2022

Abs DOI Bib

Simultaneous large-scale recordings and optogenetic interventions may hold the key to deciphering the fast-paced and multifaceted dialogue between neurons that sustains brain function. Here we have taken advantage of thin, cell-sized, optical fibers for minimally invasive optogenetics and flexible implantations. We describe a simple procedure for making those fibers side-emitting with a Lambertian emission distribution. Here we combined those fibers with silicon probes to achieve high-quality recordings and ultrafast multichannel optogenetic inhibition. Furthermore, we developed a multi-channel optical commutator and general-purpose patch-cord for flexible experiments. We demonstrate that our framework allows to conduct simultaneous laminar recordings and multifiber stimulations, 3D optogenetic stimulation, connectivity inference, and behavioral quantification in freely moving animals. Our framework paves the way for large-scale photo tagging and controlled interrogation of rapid neuronal communication in any combination of brain areas.
@article{Eriksson2022, title = {Multichannel optogenetics combined with laminar recordings for ultra-controlled neuronal interrogation}, volume = {13}, issn = {2041-1723}, url = {http://dx.doi.org/10.1038/s41467-022-28629-6}, doi = {10.1038/s41467-022-28629-6}, number = {1}, journal = {Nature Communications}, publisher = {Springer Science and Business Media LLC}, author = {Eriksson, David and Schneider, Artur and Thirumalai, Anupriya and Alyahyay, Mansour and de la Crompe, Brice and Sharma, Kirti and Ruther, Patrick and Diester, Ilka}, year = {2022}, month = feb, dimensions = {true}, keywords = {Animal, J}, }
Conserved structures of neural activity in sensorimotor cortex of freely moving rats allow cross-subject decoding

Svenja Melbaum, Eleonora Russo, David Eriksson, and 4 more authors

Nature Communications, Feb 2022

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Our knowledge about neuronal activity in the sensorimotor cortex relies primarily on stereotyped movements that are strictly controlled in experimental settings. It remains unclear how results can be carried over to less constrained behavior like that of freely moving subjects. Toward this goal, we developed a self-paced behavioral paradigm that encouraged rats to engage in different movement types. We employed bilateral electrophysiological recordings across the entire sensorimotor cortex and simultaneous paw tracking. These techniques revealed behavioral coupling of neurons with lateralization and an anterior–posterior gradient from the premotor to the primary sensory cortex. The structure of population activity patterns was conserved across animals despite the severe under-sampling of the total number of neurons and variations in electrode positions across individuals. We demonstrated cross-subject and cross-session generalization in a decoding task through alignments of low-dimensional neural manifolds, providing evidence of a conserved neuronal code.
@article{melbaum_conserved_2022, title = {Conserved structures of neural activity in sensorimotor cortex of freely moving rats allow cross-subject decoding}, volume = {13}, issn = {2041-1723}, url = {https://www.nature.com/articles/s41467-022-35115-6}, doi = {10.1038/s41467-022-35115-6}, pages = {7420}, number = {1}, journal = {Nature Communications}, shortjournal = {Nat Commun}, author = {Melbaum, Svenja and Russo, Eleonora and Eriksson, David and Schneider, Artur and Durstewitz, Daniel and Brox, Thomas and Diester, Ilka}, date = {2022-12-02}, year = {2022}, langid = {english}, dimensions = {true}, keywords = {Animal, J}, }
Poster

3D pose estimation enables virtual head-fixation in freely moving rats

Artur Schneider, Christian Zimmermann, Thomas Brox, and 1 more author

Feb 2022

NCM Society meeting

2021

Effects of Optogenetic Stimulation of Primary Somatosensory Cortex and Its Projections to Striatum on Vibrotactile Perception in Freely Moving Rats

Zongpeng Sun, Artur Schneider, Mansour Alyahyay, and 2 more authors

eneuro, Feb 2021

DOI Bib

@article{Sun2021,
  title = {Effects of Optogenetic Stimulation of Primary Somatosensory Cortex and Its Projections to Striatum on Vibrotactile Perception in Freely Moving Rats},
  volume = {8},
  issn = {2373-2822},
  url = {http://dx.doi.org/10.1523/eneuro.0453-20.2021},
  doi = {10.1523/eneuro.0453-20.2021},
  number = {2},
  journal = {eneuro},
  publisher = {Society for Neuroscience},
  author = {Sun, Zongpeng and Schneider, Artur and Alyahyay, Mansour and Karvat, Golan and Diester, Ilka},
  year = {2021},
  month = feb,
  pages = {ENEURO.0453--20.2021},
  keywords = {Animal, J},
  dimensions = {true},
  astract = {Tactile sensation is one of our primary means to collect information about the nearby environment and thus crucial for daily activities and survival. Therefore, it is of high importance to restore sensory feedback after sensory loss. Optogenetic manipulation allows local or pathway-specific write-in of information. However, it remains elusive whether optogenetic stimulation can be interpreted as tactile sensation to guide operant behavior and how it is integrated with tactile stimuli. To address these questions, we employed a vibrotactile detection task combined with optogenetic neuromodulation in freely moving rats. By bidirectionally manipulating the activity of neurons in primary somatosensory cortex (S1), we demonstrated that optical activation as well as inhibition of S1 reduced the detection rate for vibrotactile stimuli. Interestingly, activation of corticostriatal terminals improved the detection of tactile stimuli, while inhibition of corticostriatal terminals did not affect the performance. To manipulate the corticostriatal pathway more specifically, we employed a dual viral system. Activation of corticostriatal cell bodies disturbed the tactile perception while activation of corticostriatal terminals slightly facilitated the detection of vibrotactile stimuli. In the absence of tactile stimuli, both corticostriatal cell bodies as well as terminals caused a reaction. Taken together, our data confirmed the possibility to restore sensation using optogenetics and demonstrated that S1 and its descending projections to striatum play differential roles in the neural processing underlying vibrotactile detection.},
}

Distinct dynamics of neuronal activity during concurrent motor planning and execution

David Eriksson, Mona Heiland, Artur Schneider, and 1 more author

Nature Communications, Sep 2021

Abs DOI Bib

The smooth conduct of movements requires simultaneous motor planning and execution according to internal goals. So far it remains unknown how such movement plans are modified without interfering with ongoing movements. Previous studies have isolated planning and execution-related neuronal activity by separating behavioral planning and movement periods in time by sensory cues. Here, we separate continuous self-paced motor planning from motor execution statistically, by experimentally minimizing the repetitiveness of the movements. This approach shows that, in the rat sensorimotor cortex, neuronal motor planning processes evolve with slower dynamics than movement-related responses. Fast-evolving neuronal activity precees skilled forelimb movements and is nested within slower dynamics. We capture this effect via high-pass filtering and confirm the results with optogenetic stimulations. The various dynamics combined with adaptation-based high-pass filtering provide a simple principle for separating concurrent motor planning and execution.
@article{Eriksson2021, title = {Distinct dynamics of neuronal activity during concurrent motor planning and execution}, volume = {12}, issn = {2041-1723}, url = {http://dx.doi.org/10.1038/s41467-021-25558-8}, doi = {10.1038/s41467-021-25558-8}, number = {1}, journal = {Nature Communications}, publisher = {Springer Science and Business Media LLC}, author = {Eriksson, David and Heiland, Mona and Schneider, Artur and Diester, Ilka}, year = {2021}, month = sep, keywords = {Animal, J}, dimensions = {true}, }
Multifunctional optrode for opsin delivery, optical stimulation, and electrophysiological recordings in freely moving rats

Kirti Sharma, Zoë Jäckel, Artur Schneider, and 3 more authors

Journal of Neural Engineering, Nov 2021

Abs DOI Bib

Objective. Optogenetics involves delivery of light-sensitive opsins to the target brain region, as well as introduction of optical and electrical devices to manipulate and record neural activity, respectively, from the targeted neural population. Combining these functionalities in a single implantable device is of great importance for a precise investigation of neural networks while minimizing tissue damage. Approach. We report on the development, characterization, and in vivo validation of a multifunctional optrode that combines a silicon-based neural probe with an integrated microfluidic channel, and an optical glass fiber in a compact assembly. The silicon probe comprises an 11-µm-wide fluidic channel and 32 recording electrodes (diameter 30 µm) on a tapered probe shank with a length, thickness, and maximum width of 7.5 mm, 50 µm, and 150 µm, respectively. The size and position of fluidic channels, electrodes, and optical fiber can be precisely tuned according to the in vivo application. Main results. With a total system weight of 0.97 g, our multifunctional optrode is suitable for chronic in vivo experiments requiring simultaneous drug delivery, optical stimulation, and neural recording. We demonstrate the utility of our device in optogenetics by injecting a viral vector carrying a ChR2-construct in the prefrontal cortex and subsequent photostimulation of the transduced neurons while recording neural activity from both the target and adjacent regions in a freely moving rat for up to 9 weeks post-implantation. Additionally, we demonstrate a pharmacological application of our device by injecting GABA antagonist bicuculline in an anesthetized rat brain and simultaneously recording the electrophysiological response. Significance. Our triple-modality device enables a single-step optogenetic surgery. In comparison to conventional multi-step surgeries, our approach achieves higher spatial specificity while minimizing tissue damage.
@article{Sharma2021, title = {Multifunctional optrode for opsin delivery, optical stimulation, and electrophysiological recordings in freely moving rats}, volume = {18}, issn = {1741-2552}, url = {http://dx.doi.org/10.1088/1741-2552/ac3206}, doi = {10.1088/1741-2552/ac3206}, number = {6}, journal = {Journal of Neural Engineering}, publisher = {IOP Publishing}, author = {Sharma, Kirti and J\"{a}ckel, Zoë and Schneider, Artur and Paul, Oliver and Diester, Ilka and Ruther, Patrick}, year = {2021}, month = nov, pages = {066013}, dimensions = {true}, keywords = {Animal, J}, }

2020

Real-time detection of neural oscillation bursts allows behaviourally relevant neurofeedback

Golan Karvat, Artur Schneider, Mansour Alyahyay, and 3 more authors

Communications Biology, Feb 2020

Abs DOI Bib

Neural oscillations as important information carrier in the brain, are increasingly interpreted as transient bursts rather than as sustained oscillations. Short (<150 ms) bursts of beta-waves (15–30 Hz) have been documented in humans, monkeys and mice. These events were correlated with memory, movement and perception, and were even suggested as the primary ingredient of all beta-band activity. However, a method to measure these short-lived events in real-time and to investigate their impact on behaviour is missing. Here we present a real-time data analysis system, capable to detect short narrowband bursts, and demonstrate its usefulness to increase the beta-band burst-rate in rats. This neurofeedback training induced changes in overall oscillatory power, and bursts could be decoded from the movement of the rats, thus enabling future investigation of the role of oscillatory bursts.
@article{Karvat2020, title = {Real-time detection of neural oscillation bursts allows behaviourally relevant neurofeedback}, volume = {3}, issn = {2399-3642}, url = {http://dx.doi.org/10.1038/s42003-020-0801-z}, doi = {10.1038/s42003-020-0801-z}, number = {1}, journal = {Communications Biology}, publisher = {Springer Science and Business Media LLC}, author = {Karvat, Golan and Schneider, Artur and Alyahyay, Mansour and Steenbergen, Florian and Tangermann, Michael and Diester, Ilka}, year = {2020}, month = feb, keywords = {Animal, J}, dimensions = {true}, }

A starting kit for training and establishing in vivo electrophysiology, intracranial pharmacology, and optogenetics

David Eriksson, Megan Schneck, Artur Schneider, and 2 more authors

Feb 2020

Abs DOI Bib

In accordance with the three R principles of research, animal usage should be limited as much as possible. Especially for the training of entry-level scientists in surgical techniques underlying opto- and electrophysiology, alternative training tools are required before moving on to live animals. We have developed a cost-effective rat brain model for training a wide range of surgical techniques, including, but not limited to optogenetics, electrophysiology, and intracranial pharmacological treatments.

@article{eriksson_starting_2020,
  title = {A starting kit for training and establishing in vivo electrophysiology, intracranial pharmacology, and optogenetics},
  volume = {336},
  issn = {01650270},
  url = {https://linkinghub.elsevier.com/retrieve/pii/S0165027020300583},
  doi = {10.1016/j.jneumeth.2020.108636},
  pages = {108636},
  journaltitle = {Journal of Neuroscience Methods},
  shortjournal = {Journal of Neuroscience Methods},
  author = {Eriksson, David and Schneck, Megan and Schneider, Artur and Coulon, Philippe and Diester, Ilka},
  year = {2020},
  date = {2020-04},
  langid = {english},
  keywords = {Animal, J},
  dimensions = {true},
}

Poster

FreiPose 3D motion capturing allows behavioral classification in freely moving animals and reveals neuronal multiplexing

Artur Schneider, Christian Zimmermann, Thomas Brox, and 1 more author

Feb 2020

FENS meeting

2019

Poster

Marker free 3D tracking reveals insights into the role of the motor cortex in movement planning and execution in freely moving rodents

Artur Schneider, Christian Zimmermann, Thomas Brox, and 1 more author

Feb 2019

SFN meeting

2018

Silencing of TGF-beta signalling in microglia results in impaired homeostasis

Tanja Zöller, Artur Schneider, Christian Kleimeyer, and 6 more authors

Feb 2018

Abs DOI

TGFβ1 has been implicated in regulating functional aspects of several distinct immune cell populations including central nervous system (CNS) resident microglia. Activation and priming of microglia have been demonstrated to contribute to the progression of neurodegenerative diseases and, thus, underlie stringent control by endogenous regulatory factors including TGFβ1. Here, we demonstrate that deletion of Tgfbr2 in adult postnatal microglia does neither result in impairment of the microglia-specific gene expression signatures, nor is microglial survival and maintenance affected. Tgfbr2 -deficient microglia were characterised by distinct morphological changes and transcriptome analysis using RNAseq revealed that loss of TGFβ signalling results in upregulation of microglia activation and priming markers. Moreover, protein arrays demonstrated increased secretion of CXCL10 and CCL2 accompanied by activation of immune cell signalling as evidenced by increased phosphorylation of TAK1. Together, these data underline the importance of microglial TGF\β signalling to regulate microglia adaptive changes.