Evidence map›Paper›PMID 41879560›Full record

ArticleEpilepsia open2026

Microelectrode array scaled for human hippocampal slices.

Anssi Pelkonen, Vera Lezhneva, Tomi Ryynänen, Joose Kreutzer, Valeriia Sitnikova, Mireia Gómez-Budia, Adriana Della Pietra, Antonios Dougalis, Jenni Kyyriäinen, Mastaneh Torkamani-Azar and 7 more

Abstract read
In one paragraph

Article in Epilepsia open, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

17 authors.

Anssi PelkonenA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0002-4154-5686
Vera LezhnevaA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0002-0403-2646
Tomi RyynänenFaculty of Medicine and Health Technology, Biomedical Technology, Tampere University, Tampere, Finland.ORCID https://orcid.org/0000-0001-7424-1841
Joose KreutzerFaculty of Medicine and Health Technology, Biomedical Technology, Tampere University, Tampere, Finland.ORCID https://orcid.org/0000-0001-5964-8707
Valeriia SitnikovaA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0002-8192-1236
Mireia Gómez-BudiaA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0002-2194-2510
Adriana Della PietraA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0001-6417-5967
Antonios DougalisA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0002-2139-1616
Jenni KyyriäinenA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
Mastaneh Torkamani-AzarA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0001-6172-7842
Henri EronenNeurology, Institute of Clinical Medicine, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
Tuomas RauramaaPathology and Forensic Medicine, Institute of Clinical Medicine, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0002-2250-327X
Arto ImmonenNeuroCenter Neurosurgery, Kuopio University Hospital, Kuopio, Finland.
Ville LeinonenNeuroCenter Neurosurgery, Kuopio University Hospital, Kuopio, Finland.ORCID https://orcid.org/0000-0002-4282-4687
Alejandra SierraA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0001-5399-2056
Reetta KälviäinenNeurology, Institute of Clinical Medicine, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0003-2935-5131
Tarja MalmA. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.ORCID https://orcid.org/0000-0002-9530-7472

Funding

Jane ja Aatos Erkon SäätiöTampere Institute for Advanced StudyVaajasalo Foundation
6 · The paper itself

Abstract

objectiveTemporal lobe epilepsy (TLE) is characterized by recurrent seizures originating usually from the hippocampus, and approximately one-third of TLE patients remain refractory to pharmacological interventions. Surgical resection offers a potential cure for refractory TLE cases, with approximately 70% achieving seizure freedom. Still, the pathogenesis of TLE remains poorly understood. Electrophysiological characterization of the resected tissue with microelectrode arrays (MEAs) can help reveal the pathogenesis of TLE, but the commercially available MEAs cover only a small part of the hippocampal cross-section. The objective here is to develop a MEA that can cover a significant area of a human hippocampal slice to help understand the electrophysiology of TLE pathogenesis.

methodsThe custom MEA, entitled Hippo-MEA, was designed to have 60 round electrodes, each 60 μm in diameter, in an area of 5.6 mm × 5.6 mm. The titanium nitride-coated electrodes were deposited on borosilicate glass using ion beam-assisted e-beam deposition (IBAD) process. Hippo-MEA's sample chamber, named Sample Cup, was designed large enough to hold a human hippocampal slice. Hippocampal samples were obtained from patients undergoing neurosurgical tissue resection for TLE treatment and sliced to 300 μm thick sections for Hippo-MEA recording. Data from the Hippo-MEA were recorded using the commercially available MEA2100-Mini-system. Cellular composition of the recording area was analyzed with immunohistochemistry (IHC).

resultsExtracellular action potentials (EAPs) and local field potentials (LFPs) were successfully recorded from acute human hippocampal slices. Activity was mainly localized to the dentate gyrus, whereas the CA regions found sclerotic and gliotic in IHC analysis showed little to no activity. SIGNIFICANCE: Hippo-MEA is compatible with a commercially available and widely used data acquisition system and enables recording of EAPs and LFPs across several regions of human hippocampal tissue. This enables Hippo-MEA, in combination with other methods, to help discover the neurophysiological mechanisms of TLE. PLAIN LANGUAGE SUMMARY: In some cases of temporal lobe epilepsy (TLE), the only treatment option is to surgically remove a part of the brain, including a structure known as the hippocampus, which is often the source of the electrical epileptic activity. Understanding hippocampal function is important to understanding the reasons behind TLE and designing the surgeries. Microelectrode arrays (MEAs) are a tool for recording the electrical function of tissues. Here we present a new MEA, named Hippo-MEA, that is big enough to measure a cross-section of the human hippocampus.

Indexed as

Epilepsy, Temporal LobeHippocampusLocal Field Potential MeasurementHumansMicroelectrodesaction potentialhippocampuslocal field potential measurementmicroelectrode arraytemporal lobe epilepsy

Identifiers

PMID41879560
PMCPMC13238790

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.