[{"publication_identifier":{"eissn":["1476-4687"],"issn":["0028-0836"]},"publication":"Nature","license":"https://creativecommons.org/licenses/by-nc-nd/4.0/","page":"439-447","month":"07","status":"public","abstract":[{"text":"Evading imminent threat from predators is critical for animal survival. Effective defensive strategies can vary, even between closely related species. However, the neural basis of such species-specific behaviours remains poorly understood1,2,3,4. Here we find that two sister species of deer mice (genus Peromyscus)5 show different responses to the same looming stimulus: Peromyscus maniculatus, which occupies densely vegetated habitats, predominantly escapes, whereas the open field specialist, Peromyscus polionotus, briefly freezes. This difference arises from species-specific escape thresholds, is largely context-independent, and can be triggered by both visual and auditory threat stimuli. Using immunohistochemistry and electrophysiological recordings, we find that although visual threat activates the superior colliculus in both species, the role of the dorsal periaqueductal grey (dPAG) in driving behaviour differs. Whereas dPAG activity scales with running speed in P. maniculatus, neural activity in the dPAG of P. polionotus correlates poorly with movement, including during visually triggered escape. Moreover, optogenetic activation of dPAG neurons elicits acceleration in P. maniculatus but not in P. polionotus, and their chemogenetic inhibition during a looming stimulus delays escape onset in P. maniculatus to match that of P. polionotus. Together, we trace species-specific escape thresholds to a central circuit node, downstream of peripheral sensory neurons, localizing an ecologically relevant behavioural difference to a specific region of the mammalian brain.","lang":"eng"}],"quality_controlled":"1","oa":1,"OA_type":"hybrid","date_created":"2025-08-03T22:01:31Z","volume":645,"article_processing_charge":"Yes (in subscription journal)","publisher":"Springer Nature","file_date_updated":"2025-12-30T07:39:45Z","article_type":"original","ddc":["570"],"department":[{"_id":"GradSch"}],"intvolume":"       645","_id":"20101","oa_version":"Published Version","type":"journal_article","title":"The neural basis of species-specific defensive behaviour in Peromyscus mice","OA_place":"publisher","author":[{"full_name":"Baier, Felix","first_name":"Felix","last_name":"Baier"},{"last_name":"Reinhard","first_name":"Katja","full_name":"Reinhard, Katja"},{"first_name":"Bram","last_name":"Nuttin","full_name":"Nuttin, Bram"},{"first_name":"Arnau","last_name":"Sans-Dublanc","full_name":"Sans-Dublanc, Arnau"},{"full_name":"Liu, Chen","first_name":"Chen","last_name":"Liu"},{"first_name":"Victoria","last_name":"Tong","full_name":"Tong, Victoria"},{"full_name":"Murmann, Julie Stefanie","first_name":"Julie Stefanie","id":"1d390868-f128-11eb-9611-a0ca5f7833b5","last_name":"Murmann"},{"last_name":"Wierda","first_name":"Keimpe","full_name":"Wierda, Keimpe"},{"first_name":"Karl","last_name":"Farrow","full_name":"Farrow, Karl"},{"first_name":"Hopi E.","last_name":"Hoekstra","full_name":"Hoekstra, Hopi E."}],"citation":{"ama":"Baier F, Reinhard K, Nuttin B, et al. The neural basis of species-specific defensive behaviour in Peromyscus mice. <i>Nature</i>. 2025;645:439-447. doi:<a href=\"https://doi.org/10.1038/s41586-025-09241-2\">10.1038/s41586-025-09241-2</a>","ieee":"F. Baier <i>et al.</i>, “The neural basis of species-specific defensive behaviour in Peromyscus mice,” <i>Nature</i>, vol. 645. Springer Nature, pp. 439–447, 2025.","apa":"Baier, F., Reinhard, K., Nuttin, B., Sans-Dublanc, A., Liu, C., Tong, V., … Hoekstra, H. E. (2025). The neural basis of species-specific defensive behaviour in Peromyscus mice. <i>Nature</i>. Springer Nature. <a href=\"https://doi.org/10.1038/s41586-025-09241-2\">https://doi.org/10.1038/s41586-025-09241-2</a>","short":"F. Baier, K. Reinhard, B. Nuttin, A. Sans-Dublanc, C. Liu, V. Tong, J.S. Murmann, K. Wierda, K. Farrow, H.E. Hoekstra, Nature 645 (2025) 439–447.","chicago":"Baier, Felix, Katja Reinhard, Bram Nuttin, Arnau Sans-Dublanc, Chen Liu, Victoria Tong, Julie Stefanie Murmann, Keimpe Wierda, Karl Farrow, and Hopi E. Hoekstra. “The Neural Basis of Species-Specific Defensive Behaviour in Peromyscus Mice.” <i>Nature</i>. Springer Nature, 2025. <a href=\"https://doi.org/10.1038/s41586-025-09241-2\">https://doi.org/10.1038/s41586-025-09241-2</a>.","ista":"Baier F, Reinhard K, Nuttin B, Sans-Dublanc A, Liu C, Tong V, Murmann JS, Wierda K, Farrow K, Hoekstra HE. 2025. The neural basis of species-specific defensive behaviour in Peromyscus mice. Nature. 645, 439–447.","mla":"Baier, Felix, et al. “The Neural Basis of Species-Specific Defensive Behaviour in Peromyscus Mice.” <i>Nature</i>, vol. 645, Springer Nature, 2025, pp. 439–47, doi:<a href=\"https://doi.org/10.1038/s41586-025-09241-2\">10.1038/s41586-025-09241-2</a>."},"publication_status":"published","date_updated":"2026-07-22T06:20:09Z","date_published":"2025-07-23T00:00:00Z","external_id":{"pmid":["40702175"]},"tmp":{"name":"Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)","legal_code_url":"https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode","image":"/images/cc_by_nc_nd.png","short":"CC BY-NC-ND (4.0)"},"file":[{"file_size":53301589,"checksum":"7ea846a7a49b3b2a248f6a27ab13d591","file_name":"2025_Nature_Baier.pdf","content_type":"application/pdf","date_updated":"2025-12-30T07:39:45Z","relation":"main_file","file_id":"20884","success":1,"creator":"dernst","date_created":"2025-12-30T07:39:45Z","access_level":"open_access"}],"pmid":1,"year":"2025","day":"23","doi":"10.1038/s41586-025-09241-2","scopus_import":"1","related_material":{"record":[{"relation":"research_data","id":"20883","status":"public"}]},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","has_accepted_license":"1","acknowledgement":"The authors thank M. Yilmaz, M. Meister, M. Joesch and T. Branco for advice on the behavioural experiments; C. Dulac, V. Bitsikas, E. Diel and J. Chen for advice on the immunohistochemistry and RNAscope experiments; J. Greenwood and E. Soucy for technical and engineering help; A. Chrzanowska for help and advice on optogenetic experiments; A. Calzoni for help aligning histological sections to a brain atlas; S. Worthington for statistical advice; P. Gonçalves for advice with the electrophysiology analysis; I. Vlaemick for help with whole cell experiments; R. Hellmiss for figure design; B. Sabatini, V. Stempel, K. Tyssowski and N. Sanguinetti for feedback on the manuscript; and Y. M. Lee and A. Tomcho for photos of P. maniculatus and P. leucopus habitats (Fig. 1). F.B. was supported by an HHMI International Student Research Fellowship, a Grant-in-Aid of the American Society of Mammalogy, a Herchel Smith Graduate Fellowship, a Robert A. Chapman Memorial Scholarship, and a Joan Brockman Williamson Fellowship. This project received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement 665501 and by the FWO (12S7917N and 12S7920N) to K.R. and from European Research Council (ERC) (grant agreement 101075848) to K.R. V.T. was supported by a Harvard PRISE fellowship and a Harvard Museum of Comparative Zoology grant for undergraduate research. K.F. is supported by the FWO (G094616N and G091719N) and the NIH (1R01EY032101). This work was supported by the Howard Hughes Medical Institute, of which H.E.H. was an Investigator.","language":[{"iso":"eng"}]},{"OA_place":"repository","citation":{"short":"B. Felix, K. Reinhard, B. Nuttin, A. Sans Dublanc, C. Liu, V. Tong, J.S. Murmann, K. Wierda, K. Farrow, H. Hoekstra, (2025).","chicago":"Felix, Baier, Katja Reinhard, Bram Nuttin, Arnau Sans Dublanc, Chen Liu, Victoria Tong, Julie Stefanie Murmann, Keimpe Wierda, Karl Farrow, and Hopi Hoekstra. “The Neural Basis of Species-Specific Defensive Behaviour in Peromyscus Mice.” Dryad, 2025. <a href=\"https://doi.org/10.5061/DRYAD.Q2BVQ83XC\">https://doi.org/10.5061/DRYAD.Q2BVQ83XC</a>.","ista":"Felix B, Reinhard K, Nuttin B, Sans Dublanc A, Liu C, Tong V, Murmann JS, Wierda K, Farrow K, Hoekstra H. 2025. The neural basis of species-specific defensive behaviour in Peromyscus mice, Dryad, <a href=\"https://doi.org/10.5061/DRYAD.Q2BVQ83XC\">10.5061/DRYAD.Q2BVQ83XC</a>.","mla":"Felix, Baier, et al. <i>The Neural Basis of Species-Specific Defensive Behaviour in Peromyscus Mice</i>. Dryad, 2025, doi:<a href=\"https://doi.org/10.5061/DRYAD.Q2BVQ83XC\">10.5061/DRYAD.Q2BVQ83XC</a>.","ama":"Felix B, Reinhard K, Nuttin B, et al. The neural basis of species-specific defensive behaviour in Peromyscus mice. 2025. doi:<a href=\"https://doi.org/10.5061/DRYAD.Q2BVQ83XC\">10.5061/DRYAD.Q2BVQ83XC</a>","ieee":"B. Felix <i>et al.</i>, “The neural basis of species-specific defensive behaviour in Peromyscus mice.” Dryad, 2025.","apa":"Felix, B., Reinhard, K., Nuttin, B., Sans Dublanc, A., Liu, C., Tong, V., … Hoekstra, H. (2025). The neural basis of species-specific defensive behaviour in Peromyscus mice. Dryad. <a href=\"https://doi.org/10.5061/DRYAD.Q2BVQ83XC\">https://doi.org/10.5061/DRYAD.Q2BVQ83XC</a>"},"author":[{"first_name":"Baier","last_name":"Felix","full_name":"Felix, Baier"},{"full_name":"Reinhard, Katja","last_name":"Reinhard","first_name":"Katja"},{"last_name":"Nuttin","first_name":"Bram","full_name":"Nuttin, Bram"},{"full_name":"Sans Dublanc, Arnau","first_name":"Arnau","last_name":"Sans Dublanc"},{"first_name":"Chen","last_name":"Liu","full_name":"Liu, Chen"},{"first_name":"Victoria","last_name":"Tong","full_name":"Tong, Victoria"},{"full_name":"Murmann, Julie Stefanie","first_name":"Julie Stefanie","id":"1d390868-f128-11eb-9611-a0ca5f7833b5","last_name":"Murmann"},{"first_name":"Keimpe","last_name":"Wierda","full_name":"Wierda, Keimpe"},{"last_name":"Farrow","first_name":"Karl","full_name":"Farrow, Karl"},{"full_name":"Hoekstra, Hopi","first_name":"Hopi","last_name":"Hoekstra"}],"title":"The neural basis of species-specific defensive behaviour in Peromyscus mice","_id":"20883","department":[{"_id":"GradSch"}],"type":"research_data_reference","oa_version":"Published Version","article_processing_charge":"No","related_material":{"record":[{"status":"public","id":"20101","relation":"used_in_publication"}]},"oa":1,"date_created":"2025-12-30T07:36:29Z","OA_type":"hybrid","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","main_file_link":[{"url":"https://doi.org/10.5061/dryad.q2bvq83xc","open_access":"1"}],"publisher":"Dryad","date_updated":"2026-07-22T06:20:09Z","date_published":"2025-06-23T00:00:00Z","status":"public","doi":"10.5061/DRYAD.Q2BVQ83XC","abstract":[{"text":"Evading imminent predator threat is critical for survival. Effective defensive strategies can vary, even between closely related species. However, the neural basis of such species-specific behaviours is still poorly understood. Here we find that two sister species of deer mice (genus Peromyscus) show different responses to the same looming stimulus: P. maniculatus, which occupies densely vegetated habitats, predominantly escapes, while the open field specialist, P. polionotus, briefly freezes. This difference arises from species-specific escape thresholds, is largely context-independent, and can be triggered by both visual and auditory threat stimuli. Using immunohistochemistry and electrophysiological recordings, we find that although visual threat activates the superior colliculus in both species, the role of the dorsal periaqueductal gray (dPAG) in driving behaviour differs. While dPAG activity scales with running speed in P. maniculatus, neural activity in the dPAG of P. polionotus correlates poorly with movement, including during visually triggered escape. Moreover, optogenetic activation of dPAG neurons elicits acceleration in P. maniculatus but not P. polionotus, while their chemogenetic inhibition during a looming stimulus delays escape onset in P. maniculatus to match that of P. polionotus. Together, we trace species-specific escape thresholds to a central circuit node, downstream of peripheral sensory neurons, localizing an ecologically relevant behavioural difference to a specific region of the mammalian brain.","lang":"eng"}],"year":"2025","day":"23","month":"06"},{"degree_awarded":"MS","publication_identifier":{"issn":["2791-4585"]},"ddc":["570"],"publisher":"Institute of Science and Technology Austria","file_date_updated":"2025-05-02T22:30:04Z","article_processing_charge":"No","oa":1,"date_created":"2024-05-02T08:31:38Z","status":"public","abstract":[{"lang":"eng","text":"Epilepsy affects about 50 to 65 million people globally. It summarizes a spectrum of neurological\r\ndisorders that have in common a hyperactivity of the neuronal network resulting in seizures. A common\r\nassumption is that an imbalance between neuronal excitation and inhibition is a key mechanism in\r\nseizure generation and epileptogeneisis. In at least one-third of the patients, current therapies have\r\nproven unsuccessful in treating seizure progression. One potential reason could be that the therapies\r\nonly focus on neurons. Recent studies suggest that neuronal hyperactivity causes a microglial\r\nresponse, which reinstates brain homeostasis. Additionally, interactions between microglia and neurons\r\nhave been shown to inhibit neuronal firing and dampen seizure activity. However, the exact relationship\r\nbetween microglia and seizure progression in epilepsy is yet to be elucidated. A main bottleneck is that\r\nseveral studies investigate microglia dynamics in ex vivo slice models, which can severely affect the\r\nmicroglia dynamics due to their rapid response to environmental changes. On the other hand, in vivo\r\nstudies focus mostly on behavior characterization of the epileptic seizure phenotype and their long-term\r\nconsequences on microglia activity leaving out the direct consequences of acute seizure activity on\r\nmicroglia dynamics.\r\nHere, we perform a pilot study to combine electroencephalography (EEG) and in vivo live imaging to\r\ndirectly monitor and correlate the onset of seizure activity with microglia response. To induce seizures,\r\nwe take advantage of the kainic acid (KA) model, which represents similar neuropathological and\r\nelectroencephalographic features seen in human patients with temporal lobe epilepsy (TLE). After\r\nconfirmation of induction of the seizure and microglia activity in the hippocampus as a focal point, we\r\ninvestigated whether these changes also reached the primary visual cortex (V1) as a secondary\r\ngeneralized seizure activity. Indeed, we found that microglia changed their morphology at high doses\r\nof KA in the V1. Next, we optimized each of the two methodological components: for the EEG recording,\r\nour initial attempts under the microscope suffered from extensive electrical noise, which overlaid the\r\nactual signal. Thus, we built a customized Faraday-cage and confirmed that the signal-to-noise ratio\r\nwas sufficiently reduced to be able to record brain oscillatory activity. For the in vivo live imaging of\r\nmicroglia, we had to optimize the imaging parameters, so that we would be able to detect microglial\r\nprocesses in a sufficient resolution to track their process changes. Finally, we combined both\r\nmethodologies with the KA model. We confirmed that KA induced seizure activity and found first\r\nindication that those correlate with microglia volume changes.\r\nOverall, we have developed a first methodological approach, which allows the analysis of the acute\r\neffects of seizure onset on microglia. Future studies will have to continue to optimize the drift during\r\nimaging recording and the post-image analysis. "}],"month":"05","license":"https://creativecommons.org/licenses/by/4.0/","page":"54","OA_place":"publisher","corr_author":"1","author":[{"id":"1d390868-f128-11eb-9611-a0ca5f7833b5","last_name":"Murmann","first_name":"Julie Stefanie","full_name":"Murmann, Julie Stefanie"}],"publication_status":"published","citation":{"ama":"Murmann JS. Investigating acute microglia response to seizure activity in vivo: Combining 2-Photon imaging and EEG recording. 2024. doi:<a href=\"https://doi.org/10.15479/at:ista:15352\">10.15479/at:ista:15352</a>","ieee":"J. S. Murmann, “Investigating acute microglia response to seizure activity in vivo: Combining 2-Photon imaging and EEG recording,” Institute of Science and Technology Austria, 2024.","apa":"Murmann, J. S. (2024). <i>Investigating acute microglia response to seizure activity in vivo: Combining 2-Photon imaging and EEG recording</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/at:ista:15352\">https://doi.org/10.15479/at:ista:15352</a>","chicago":"Murmann, Julie Stefanie. “Investigating Acute Microglia Response to Seizure Activity in Vivo: Combining 2-Photon Imaging and EEG Recording.” Institute of Science and Technology Austria, 2024. <a href=\"https://doi.org/10.15479/at:ista:15352\">https://doi.org/10.15479/at:ista:15352</a>.","short":"J.S. Murmann, Investigating Acute Microglia Response to Seizure Activity in Vivo: Combining 2-Photon Imaging and EEG Recording, Institute of Science and Technology Austria, 2024.","ista":"Murmann JS. 2024. Investigating acute microglia response to seizure activity in vivo: Combining 2-Photon imaging and EEG recording. Institute of Science and Technology Austria.","mla":"Murmann, Julie Stefanie. <i>Investigating Acute Microglia Response to Seizure Activity in Vivo: Combining 2-Photon Imaging and EEG Recording</i>. Institute of Science and Technology Austria, 2024, doi:<a href=\"https://doi.org/10.15479/at:ista:15352\">10.15479/at:ista:15352</a>."},"title":"Investigating acute microglia response to seizure activity in vivo: Combining 2-Photon imaging and EEG recording","type":"dissertation","oa_version":"Published Version","_id":"15352","department":[{"_id":"SaSi"},{"_id":"GradSch"}],"supervisor":[{"orcid":"0000-0001-8635-0877","full_name":"Siegert, Sandra","id":"36ACD32E-F248-11E8-B48F-1D18A9856A87","last_name":"Siegert","first_name":"Sandra"}],"alternative_title":["ISTA Master's Thesis"],"language":[{"iso":"eng"}],"acknowledged_ssus":[{"_id":"Bio"},{"_id":"LifeSc"},{"_id":"PreCl"}],"user_id":"ba8df636-2132-11f1-aed0-ed93e2281fdd","has_accepted_license":"1","doi":"10.15479/at:ista:15352","year":"2024","day":"02","tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"file":[{"date_created":"2024-05-02T12:26:13Z","creator":"cchlebak","access_level":"open_access","file_id":"15354","date_updated":"2025-05-02T22:30:04Z","relation":"main_file","file_size":5936142,"content_type":"application/pdf","embargo":"2025-05-02","file_name":"Murmann_Thesis_final_2024_2.pdf","checksum":"095817a6c944954ac3f277e547031a33"},{"content_type":"application/x-zip-compressed","checksum":"43b632255372973a437ac87739cfd4db","embargo_to":"open_access","file_name":"Murmann_Thesis_final_2024.zip","file_size":20645510,"relation":"source_file","date_updated":"2025-05-02T22:30:04Z","file_id":"15355","access_level":"closed","date_created":"2024-05-02T12:37:56Z","creator":"cchlebak"}],"date_published":"2024-05-02T00:00:00Z","date_updated":"2026-04-07T13:05:00Z"}]