PMID-12477707[0] The cerebral oscillatory network of parkinsonian resting tremor.
- Patients had idiopathic unliateral tremor-dominated PD.
- MEG + EMG -> coherence analysis. (+ DICS for deep MEG recording).
- M1 correlated to EMG at tremor and double-tremor frequency following medication withdrawal overnight.
- M1 leads by 15 - 25 ms, consistent with conduction delay.
- Unlike other studies, they find that many cortical areas are also coherent / oscillating with M1, including:
- Cingulate and supplementary motor area (CMA / SMA)
- Lateral premotor cortex (PM).
- SII
- Posterior pareital cortex PPC
- contralateral cerebellum - strongest at double frequency.
- In contrast, the cerebellum, SMA/CMA and PM show little evidence for direct coupling with the peripheral EMG but seem to be connected with the periphery via other cerebral areas (e.g. M1)
- Power spectral analysis of activity in all central areas indicated the strongest frequency coherence at double tremor frequency.
- Especially cerebro-cerebro coupling.
- These open-ended observation studies are useful!
____References____
[0] Timmermann L, Gross J, Dirks M, Volkmann J, Freund HJ, Schnitzler A, The cerebral oscillatory network of parkinsonian resting tremor.Brain 126:Pt 1, 199-212 (2003 Jan) |
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