{"entity": "researcher", "timestamp": "2026-08-20T20:42:16.703Z", "family": "Helson", "given": "Pascal", "initials": "P", "orcid": "0000-0002-2877-3705", "affiliations": ["School of Electrical Engineering and Computer Science, Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden. pashel@kth.se."], "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/researcher/0ee66ee661c64a4a89df82afceff2e11.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/researcher/0ee66ee661c64a4a89df82afceff2e11"}}, "publications": [{"entity": "publication", "iuid": "f4e7129494c44a94b41c5c3c51389cdb", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/f4e7129494c44a94b41c5c3c51389cdb.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/f4e7129494c44a94b41c5c3c51389cdb"}}, "title": "Non-equilibrium dynamics of the neocortex in Parkinson\u2019s disease", "authors": [{"family": "Helson", "given": "Pascal", "initials": "P", "orcid": "0000-0002-2877-3705", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/0ee66ee661c64a4a89df82afceff2e11.json"}}, {"family": "Benyahiya", "given": "Elias", "initials": "E"}, {"family": "Manikandan", "given": "Sreekanth", "initials": "S"}, {"family": "Waldthaler", "given": "Josefine", "initials": "J"}, {"family": "Vinding", "given": "Mikkel C", "initials": "MC"}, {"family": "Lundqvist", "given": "Daniel", "initials": "D"}, {"family": "Svenningsson", "given": "Per", "initials": "P"}, {"family": "Mitra", "given": "Dhrubaditya", "initials": "D"}, {"family": "Kumar", "given": "Arvind", "initials": "A", "orcid": "0000-0002-8044-9195", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/cf2fe30252074acb8d09f88f6c9b55f3.json"}}], "type": "posted-content", "published": "2025-08-13", "journal": {"issn-l": null}, "abstract": null, "doi": "10.1101/2025.08.09.25333337", "pmid": null, "labels": [], "xrefs": [], "notes": [], "created": "2026-08-20T11:06:49.877Z", "modified": "2026-08-20T11:06:49.937Z"}, {"entity": "publication", "iuid": "41770c446caf4ee680281bc60b8a6e4f", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/41770c446caf4ee680281bc60b8a6e4f.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/41770c446caf4ee680281bc60b8a6e4f"}}, "title": "Structural constraints on the emergence of oscillations in multi-population neural networks.", "authors": [{"family": "Zang", "given": "Jie", "initials": "J", "orcid": "0000-0003-2655-3343", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/cda7827b6ab3406cbfc0c38859c0fada.json"}}, {"family": "Liu", "given": "Shenquan", "initials": "S"}, {"family": "Helson", "given": "Pascal", "initials": "P", "orcid": "0000-0002-2877-3705", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/0ee66ee661c64a4a89df82afceff2e11.json"}}, {"family": "Kumar", "given": "Arvind", "initials": "A", "orcid": "0000-0002-8044-9195", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/cf2fe30252074acb8d09f88f6c9b55f3.json"}}], "type": "journal article", "published": "2024-03-13", "journal": {"title": "Elife", "issn": "2050-084X", "volume": "12", "issn-l": "2050-084X"}, "abstract": "Oscillations arise in many real-world systems and are associated with both functional and dysfunctional states. Whether a network can oscillate can be estimated if we know the strength of interaction between nodes. But in real-world networks (in particular in biological networks) it is usually not possible to know the exact connection weights. Therefore, it is important to determine the structural properties of a network necessary to generate oscillations. Here, we provide a proof that uses dynamical system theory to prove that an odd number of inhibitory nodes and strong enough connections are necessary to generate oscillations in a single cycle threshold-linear network. We illustrate these analytical results in a biologically plausible network with either firing-rate based or spiking neurons. Our work provides structural properties necessary to generate oscillations in a network. We use this knowledge to reconcile recent experimental findings about oscillations in basal ganglia with classical findings.", "doi": "10.7554/eLife.88777", "pmid": "38477669", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC10937037"}, {"db": "pii", "key": "88777"}], "notes": [], "created": "2026-08-20T13:55:23.747Z", "modified": "2026-08-20T13:55:23.866Z"}, {"entity": "publication", "iuid": "58833333f12f43fa8d80edf8ded7a54a", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/58833333f12f43fa8d80edf8ded7a54a.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/58833333f12f43fa8d80edf8ded7a54a"}}, "title": "Structural constraints on the emergence of oscillations in multi-population neural networks", "authors": [{"family": "Zang", "given": "Jie", "initials": "J", "orcid": "0000-0003-2655-3343", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/cda7827b6ab3406cbfc0c38859c0fada.json"}}, {"family": "Liu", "given": "Shenquan", "initials": "S"}, {"family": "Helson", "given": "Pascal", "initials": "P", "orcid": "0000-0002-2877-3705", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/0ee66ee661c64a4a89df82afceff2e11.json"}}, {"family": "Kumar", "given": "Arvind", "initials": "A", "orcid": "0000-0002-8044-9195", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/cf2fe30252074acb8d09f88f6c9b55f3.json"}}], "type": "journal-article", "published": "2024-03-13", "journal": {"issn": "2050-084X", "volume": "12", "title": "Elife", "issn-l": "2050-084X"}, "abstract": null, "doi": "10.7554/elife.88777.3", "pmid": null, "labels": [], "xrefs": [], "notes": [], "created": "2026-08-20T13:55:25.590Z", "modified": "2026-08-20T13:55:25.672Z"}, {"entity": "publication", "iuid": "93bba24e1e8247789d1eca1dc8e97bb8", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/93bba24e1e8247789d1eca1dc8e97bb8.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/93bba24e1e8247789d1eca1dc8e97bb8"}}, "title": "Cortex-wide topography of 1/f-exponent in Parkinson's disease.", "authors": [{"family": "Helson", "given": "Pascal", "initials": "P", "orcid": "0000-0002-2877-3705", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/0ee66ee661c64a4a89df82afceff2e11.json"}}, {"family": "Lundqvist", "given": "Daniel", "initials": "D", "orcid": "0000-0003-1593-2559", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/06fbc4c5ba644ef4b6ebeb1cc39c7f08.json"}}, {"family": "Svenningsson", "given": "Per", "initials": "P", "orcid": "0000-0001-6727-3802", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/b01bbacfa24e4b9794734bf1121d1c38.json"}}, {"family": "Vinding", "given": "Mikkel C", "initials": "MC", "orcid": "0000-0002-7954-2886", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/ccaff4ee9c23497ba518325c7997701b.json"}}, {"family": "Kumar", "given": "Arvind", "initials": "A"}], "type": "journal article", "published": "2023-07-13", "journal": {"title": "NPJ Parkinsons Dis", "issn": "2373-8057", "volume": "9", "issue": "1", "pages": "109", "issn-l": null}, "abstract": "Parkinson's disease (PD) is a progressive and debilitating brain disorder. Besides the characteristic movement-related symptoms, the disease also causes decline in sensory and cognitive processing. The extent of symptoms and brain-wide projections of neuromodulators such as dopamine suggest that many brain regions are simultaneously affected in PD. To characterise brain-wide disease-related changes in neuronal function, we analysed resting state magnetoencephalogram (MEG) from two groups: PD patients and healthy controls. Besides standard spectral analysis, we quantified the aperiodic components (\u03ba, \u03bb) of the neural activity by fitting a power law \u03ba/f\u03bb - f is the frequency, \u03ba and \u03bb are the fitting parameters-to the MEG power spectrum and studied its relationship with age and Unified Parkinson's Disease Rating Scale (UPDRS). Consistent with previous results, the most significant spectral changes were observed in the high theta/low-alpha band (7-10 Hz) in all brain regions. Furthermore, analysis of the aperiodic part of the spectrum showed that in all but frontal regions \u03bb was significantly larger in PD patients than in control subjects. Our results indicate that PD is associated with significant changes in aperiodic activity across the whole neocortex. Surprisingly, even early sensory areas showed a significantly larger \u03bb in patients than in healthy controls. Moreover, \u03bb was not affected by the Levodopa medication. Finally, \u03bb was positively correlated with patient age but not with UPDRS-III. Because \u03bb is closely associated with excitation-inhibition balance, our results propose new hypotheses about neural correlates of PD in cortical networks.", "doi": "10.1038/s41531-023-00553-6", "pmid": "37438362", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC10338503"}, {"db": "pii", "key": "10.1038/s41531-023-00553-6"}], "notes": [], "created": "2026-08-20T08:54:37.789Z", "modified": "2026-08-20T08:54:37.957Z"}, {"entity": "publication", "iuid": "fd2dcf41e7b849259a479369ec513c93", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/fd2dcf41e7b849259a479369ec513c93.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/fd2dcf41e7b849259a479369ec513c93"}}, "title": "Cortex-wide topography of 1/f-exponent in Parkinson\u2019s disease", "authors": [{"family": "Helson", "given": "Pascal", "initials": "P", "orcid": "0000-0002-2877-3705", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/0ee66ee661c64a4a89df82afceff2e11.json"}}, {"family": "Lundqvist", "given": "Daniel", "initials": "D", "orcid": "0000-0003-1593-2559", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/06fbc4c5ba644ef4b6ebeb1cc39c7f08.json"}}, {"family": "Svenningsson", "given": "Per", "initials": "P", "orcid": "0000-0001-6727-3802", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/b01bbacfa24e4b9794734bf1121d1c38.json"}}, {"family": "Vinding", "given": "Mikkel C", "initials": "MC", "orcid": "0000-0002-7954-2886", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/ccaff4ee9c23497ba518325c7997701b.json"}}, {"family": "Kumar", "given": "Arvind", "initials": "A", "orcid": "0000-0002-8044-9195", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/cf2fe30252074acb8d09f88f6c9b55f3.json"}}], "type": "posted-content", "published": "2023-01-20", "journal": {"issn-l": null}, "abstract": null, "doi": "10.1101/2023.01.19.524792", "pmid": null, "labels": [], "xrefs": [], "notes": [], "created": "2026-08-20T10:43:31.079Z", "modified": "2026-08-20T10:43:31.221Z"}]}