Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy
During the generalization of epileptic seizures, pathological activity in one brain area recruits distant brain structures into joint synchronous discharges. However, it remains unknown whether specific changes in local circuit activity are related to the aberrant recruitment of anatomically distant...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2014-09-01
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| Series: | Frontiers in Neural Circuits |
| Subjects: | |
| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fncir.2014.00101/full |
| _version_ | 1817995710673453056 |
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| author | Florian B Neubauer Florian B Neubauer Audrey eSederberg Jason N MacLean Jason N MacLean |
| author_facet | Florian B Neubauer Florian B Neubauer Audrey eSederberg Jason N MacLean Jason N MacLean |
| author_sort | Florian B Neubauer |
| collection | DOAJ |
| description | During the generalization of epileptic seizures, pathological activity in one brain area recruits distant brain structures into joint synchronous discharges. However, it remains unknown whether specific changes in local circuit activity are related to the aberrant recruitment of anatomically distant structures into epileptiform discharges. Further, it is not known whether aberrant areas recruit or entrain healthy ones into pathological activity. Here we study the dynamics of local circuit activity during the spread of epileptiform discharges in the zero-magnesium in vitro model of epilepsy. We employ high-speed multi-photon imaging in combination with dual whole-cell recordings in acute thalamocortical slices of the juvenile mouse to characterize the generalization of epileptic activity between neocortex and thalamus. We find that, although both structures are exposed to zero-magnesium, the initial onset of focal epileptiform discharge occurs in cortex. This suggests that local recurrent connectivity that is particularly prevalent in cortex is important for the initiation of seizure activity. Subsequent recruitment of thalamus into joint, generalized discharges is coincident with an increase in the coherence of local cortical circuit activity that itself does not depend on thalamus. Finally, the intensity of population discharges is positively correlated between both brain areas. This suggests that during and after seizure generalization not only the timing but also the amplitude of epileptiform discharges in thalamus is entrained by cortex. Together these results suggest a central role of neocortical activity for the onset and the structure of pathological recruitment of thalamus into joint synchronous epileptiform discharges. |
| first_indexed | 2024-04-14T02:10:30Z |
| format | Article |
| id | doaj.art-915feab532294c0e89f0d7eac3a26b60 |
| institution | Directory Open Access Journal |
| issn | 1662-5110 |
| language | English |
| last_indexed | 2024-04-14T02:10:30Z |
| publishDate | 2014-09-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Neural Circuits |
| spelling | doaj.art-915feab532294c0e89f0d7eac3a26b602022-12-22T02:18:26ZengFrontiers Media S.A.Frontiers in Neural Circuits1662-51102014-09-01810.3389/fncir.2014.00101100212Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsyFlorian B Neubauer0Florian B Neubauer1Audrey eSederberg2Jason N MacLean3Jason N MacLean4The University of ChicagoUniversity of BernThe University of ChicagoThe University of ChicagoThe University of ChicagoDuring the generalization of epileptic seizures, pathological activity in one brain area recruits distant brain structures into joint synchronous discharges. However, it remains unknown whether specific changes in local circuit activity are related to the aberrant recruitment of anatomically distant structures into epileptiform discharges. Further, it is not known whether aberrant areas recruit or entrain healthy ones into pathological activity. Here we study the dynamics of local circuit activity during the spread of epileptiform discharges in the zero-magnesium in vitro model of epilepsy. We employ high-speed multi-photon imaging in combination with dual whole-cell recordings in acute thalamocortical slices of the juvenile mouse to characterize the generalization of epileptic activity between neocortex and thalamus. We find that, although both structures are exposed to zero-magnesium, the initial onset of focal epileptiform discharge occurs in cortex. This suggests that local recurrent connectivity that is particularly prevalent in cortex is important for the initiation of seizure activity. Subsequent recruitment of thalamus into joint, generalized discharges is coincident with an increase in the coherence of local cortical circuit activity that itself does not depend on thalamus. Finally, the intensity of population discharges is positively correlated between both brain areas. This suggests that during and after seizure generalization not only the timing but also the amplitude of epileptiform discharges in thalamus is entrained by cortex. Together these results suggest a central role of neocortical activity for the onset and the structure of pathological recruitment of thalamus into joint synchronous epileptiform discharges.http://journal.frontiersin.org/Journal/10.3389/fncir.2014.00101/fullNeocortexThalamusMousepatch-clamptwo-photon imagingepilepsy model |
| spellingShingle | Florian B Neubauer Florian B Neubauer Audrey eSederberg Jason N MacLean Jason N MacLean Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy Frontiers in Neural Circuits Neocortex Thalamus Mouse patch-clamp two-photon imaging epilepsy model |
| title | Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy |
| title_full | Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy |
| title_fullStr | Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy |
| title_full_unstemmed | Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy |
| title_short | Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy |
| title_sort | local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy |
| topic | Neocortex Thalamus Mouse patch-clamp two-photon imaging epilepsy model |
| url | http://journal.frontiersin.org/Journal/10.3389/fncir.2014.00101/full |
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