F Miwakeichi | PubMed Health

PubMed2002

The relationship between the visually evoked P300 event-related potential and gamma band oscillation in the human medial and basal temporal lobes: an electrocorticographic study.

We have recorded electrocorticographic activities (ECoG) from subdural electrodes on the human medial temporal lobe (MTL) and basal temporal lobe (BTL) in epileptic patients during cognitive visual tasks designed to evoke the P300 event related potential (ERP). From those recordings we examined the event related gamma band oscillation (ERGBO) and P300 ERP. While P300 was predominantly observed in the MTL, ERGBO was observed in both MTL and BTL. Resembling to P300, ERGBO responses were more often observed following rare stimuli than frequent stimuli. In average responses the ERGBO to rare stimuli followed P300, beginning at 440.5 ms and continuing for about 100 ms. Past studies suggest P300 ERP component reflects a role in cognitive function. Since ERGBO in the present study appeared in different regions and at a different latency from P300, ERGBO may reflect a different physiological role in the cognitive process.

Adult↗

PubMed2001

A comparison of non-linear non-parametric models for epilepsy data.

EEG spike and wave (SW) activity has been described through a non-parametric stochastic model estimated by the Nadaraya-Watson (NW) method. In this paper the performance of the NW, the local linear polynomial regression and support vector machines (SVM) methods were compared. The noise-free realizations obtained by the NW and SVM methods reproduced SW better than as reported in previous works. The tuning parameters had to be estimated manually. Adding dynamical noise, only the NW method was capable of generating SW similar to training data. The standard deviation of the dynamical noise was estimated by means of the correlation dimension.

Data Interpretation, Statistical↗