Use of current source density analysis to characterize subthalamic nucleus response following deep brain stimulation
Translated title
Brug af current source density analyse til at karakterisere response fra nucleus subthalamicus efter deep brain stimulation
Author
Munch, Majken
Term
4. term
Publication year
2010
Pages
59
Abstract
Parkinson’s disease causes tremor, rigidity, and slowness of movement, and high-frequency deep brain stimulation (DBS) of the subthalamic nucleus can alleviate symptoms, yet the underlying mechanisms remain unclear. This project examines whether current source density (CSD) analysis of local field potentials (LFP) can characterize and quantify changes in neural network activity following DBS. LFPs were recorded in the subthalamic nucleus of rats using a linear electrode array before and after stimulation delivered through the same array. Two experimental paradigms were used: varying stimulation duration at fixed amplitude and varying amplitude at fixed duration. CSD was computed from the LFPs, and three feature types were compared pre- and post-stimulation: CSD RMS values at each depth, the number of threshold crossings, and the intervals between crossings. Results showed that CSD RMS values most often decreased after DBS, the number of threshold crossings changed without a consistent pattern, and the intervals between crossings showed no clear changes. Interpretation is limited by one rat per experiment, the use of healthy (non-Parkinsonian) animals, the inability to record LFP during stimulation due to artifacts, and reliance on spontaneous data without external triggers. Overall, the findings suggest that CSD can detect DBS-related changes in local network activity, but larger, targeted studies are needed.
Parkinsons sygdom medfører tremor, rigiditet og langsomme bevægelser, og højfrekvent deep brain stimulation (DBS) af nucleus subthalamicus kan lindre symptomerne, men mekanismerne bag effekten er uklare. Dette projekt undersøger, om current source density (CSD) analyse af lokale feltpotentialer (LFP) kan karakterisere og kvantificere ændringer i det neurale netværk efter DBS. LFP blev optaget i nucleus subthalamicus hos rotter med en lineær elektrode, før og efter stimulation via samme elektrode. To forsøgsparadigmer blev anvendt: varierende stimuleringstid ved fast amplitude og varierende amplitude ved fast stimuleringstid. CSD blev beregnet ud fra LFP, og tre typer mål blev sammenlignet før og efter stimulation: RMS-værdier for CSD ved hver dybde, antal tærskelværdikrydsninger og intervallerne mellem disse. Resultaterne viste, at CSD-RMS-værdierne oftest faldt efter DBS, at antallet af tærskelkrydsninger ændrede sig uden et tydeligt mønster, og at intervallerne mellem krydsninger ikke viste klare ændringer. Fortolkningen begrænses af, at der kun indgik én rotte i hvert forsøg, at dyrene var raske (ikke Parkinson-modeller), at LFP ikke kunne registreres under stimulation på grund af artefakter, og at analysen bygger på spontandata uden eksterne triggere. Samlet tyder fundene på, at CSD kan opfange DBS-relaterede ændringer i lokal netværksaktivitet, men større og mere målrettede studier er nødvendige.
[This apstract has been generated with the help of AI directly from the project full text]
Keywords
CSD ; LFP ; DBS ; STN ; Parkinson's disease