led by
P.D. Dr. Jonas-Frederic Sauer
We investigate the dynamics of brain circuit activity in health and disease.
Team members
Research
We focus on how the medial prefrontal cortex (mPFC), a brain region critical for higher cortical functions, and its downstream targets enable cognitive and emotional behaviour of mice by investigating network function with a panel of in vivo methods. First, by probing the mPFC circuitry with long-term 1-photon calcium imaging, we aim to reveal organizational principles of neocortical activities over multiple timescales. Second, using mouse models of psychiatric illness, we aim to uncover how circuit dysfunction leads to behavioural deficits. We thus seek to obtain a comprehensive understanding of the neuronal network mechanisms controlling emotional and cognitive states.
Techniques
We use 1-photon calcium imaging from freely moving mice to investigate the dynamics of neuronal activity over time. Our goal is to understand how the activation of groups of neurons in various brain regions is regulated over behaviourally relevant timescales.
Selected publications:

We use single-unit and local field potential recordings from freely moving and head-fixed mice to explore the dynamics of cortical activities. Specifically, we focus on how neuronal oscillations organize spiking activity during behaviour and how these processes are impaired in psychiatric illness.
Selected publications:

Single-unit recording of electrophysiolgically identified prefrontal pyramidal cells (PYR) and GABAergic interneurons (INT). Adapted from Sauer & Bartos (2022) under CC-BY 4.0.

Channelrhodopsin(ChR2)-assisted identification of genetically defined neurons. Adapted from Sauer & Bartos (2022) under CC-BY 4.0.
We use computational tools to extract network activity patterns such as assemblies of coactive neurons from large-scale electrophysiological and imaging data. The goal of this research is to understand how higher-order population activity patterns are organized by ongoing oscillatory activity and behaviour.
Selected papers:

Assembly identification by detecting consistently coactivating neurons. Adapted from Folschweiller & Sauer (2022) und CC-BY-NC 4.0.
Publications
2024
- Muysers H, Chen HL, Hahn J, Folschweiller S, Sigurdsson T, Sauer JF*, Bartos M* (2024) A persistent prefrontal reference frame across time and task rules. Nat Commun 2115, https://doi.org/10.1038/s41467-024-46350-4 *corresponding authors (equal contribution)
- Kaufhold D, Maristany de las Casas E, Ocana-Fernandez MA, Cazala A, Yuan M, Kulik A, Cholvin T, Steup S, Sauer JF, Eyre MD, Elgueta C, Strüber M, Bartos M (2024) Spine plasticity of dentate gyrus parvalbumin-positive interneurons is regulated by experience. Cell Reports 43, 113806
- Sylte OC, Muysers M, Chen H-L, Bartos M, Sauer JF (2024) Neuronal tuning to threat exposure remains stable in the mouse prefrontal cortex over multiple days. PLOS Biology, https://doi.org/10.1371/journal.pbio.3002475
2023
2022
- Folschweiller S, Sauer JF (2022) Phase-specific pooling of sparse assembly activity by respiration-related brain oscillations. J Physiol, 600(8):1991-2011
- Sauer JF*, Bartos M* (2022) Disrupted-in-schizophrenia-1 is required for normal pyramidal cell-interneuron communication and assembly dynamics in the prefrontal cortex. eLife, 11:e79471 *corresponding authors
- Voss L, Bartos M, Elgueta C*, Sauer JF* (2022) Interneuron function and cognitive behavior are preserved upon postnatal removal of Lhx6. Sci Rep doi: 10.1038/s41598-022-09003-4 *corresponding authors
- Sauer JF*, Folschweiller S, Bartos M* (2022) Topographically organized representation of space and context in the medial prefrontal cortex. Proc Natl Acad Sci U S A. doi: 10.1073/pnas.2117300119 *corresponding authors
- Strüber M, Sauer JF, Bartos M (2022) Parvalbumin expressing interneurons control spike-phase coupling of hippocampal cells to theta oscillations. Sci Rep doi: 10.1038/s41598-022-05004-5
2021
2018
2017
- Ziegler-Waldkirch S, Errico P, Sauer JF, Erny D, Savanthrapadian S, Loreth D, Katzmarski N, Blank T, Bartos M, Prinz M, Meyer-Luehmann M (2017) Seed-induced A-beta deposition is modulated by microglia under environmental enrichment. EMBO Journal, doi: 10.15252/embj.201797021.
- Strüber M, Sauer JF, Jonas P, Bartos M (2017) Distance-dependent inhibition supports focality of gamma oscillations. Nature Commun. doi: 10.1038/s41467-017-00936-3.
- Biskamp J, Bartos M, Sauer JF (2017) Organization of prefrontal network activity by respiration-related oscillations. Sci Rep 7:45508
2015
2012
2011
- Murray AJ, Sauer J, Mcclure CJ, Cheyne LA, Riedel G, Bartos M, Wisden W, Wulff P (2011) Parvalbumin-positive hippocamapl interneurons are required for spatial working but not reference memory. Nat Neurosci 14:297-299.
- Sauer J-F, Bartos M (2011) Postnatal differentiation of cortical interneuron signalling. Eur J Neurosci 34:1687-1696.
2010
- Sambandan S, Sauer JF, Vida I, Bartos M (2010) Associative plasticity at excitatory synapses facilitates recruitment of fast-spiking interneurons in the dentate gyrus. J Neurosci 30:11826-11837.
- Sauer J, Bartos M (2010) Efficient recruitment of young hippocampal interneurons by early excitatory GABAergic synapses. J Neurosci 30:110-115.
- Hanganu-Opatz IL, Klausberger T, Sigurdsson T, Nieder A, Jacob SN, Bartos M, Sauer JF, Durstewitz D, Leibold C, Diester I (2023) Resolving the prefrontal mechanisms of adaptive cognitive behaviors: A cross-species perspective. Neuron 111:1020-1036.
- Folschweiller S, Sauer J-F (2023) Controlling neuronal assemblies: a fundamental function of respiration-related brain oscillations in neuronal networks. Pflügers Arch. 475(1):13-21
- Folschweiller S, Sauer J-F (2021) Respiration-driven brain oscillations in emotional cognition. Front Neural Circuits 15:761812.
- Sauer J-F, Bartos M (2011) Postnatal differentiation of cortical interneuron signalling. Eur J Neurosci 34:1687-1696.
Bartos M, Sauer J, Kulik A, Vida I (2010) Fast and strong inhibition in the hippocampal circuitry. “Hippocampal Microcircuits: A Computational Modeller’s Resource Book”, Springer (USA). 1st Edition January 2010.
Alumni
Dr. Hannah Muysers
Dr. Shani Folschweiller
Dr. Lars Voss
Dr. Jonatan Biskamp