https://repositorio.fleni.org.ar/xmlui/handle/123456789/274 2026-04-05T23:08:09Z https://repositorio.fleni.org.ar/xmlui/handle/123456789/577 Mu-suppression detection in motor imagery electroencephalographic signals using the generalized extreme value distribution Quintero Rincón, Antonio; D’Giano, Carlos; Batatia, Hadj This paper deals with the detection of mu-suppression from electroencephalographic (EEG) signals in brain-computer interface (BCI). For this purpose, an efficient algorithm is proposed based on a statistical model and a linear classifier. Precisely, the generalized extreme value distribution (GEV) is proposed to represent the power spectrum density of the EEG signal in the central motor cortex. The associated three parameters are estimated using the maximum likelihood method. Based on these parameters, a simple and efficient linear classifier was designed to classify three types of events: imagery, movement, and resting. Preliminary results show that the proposed statistical model can be used in order to detect precisely the mu-suppression and distinguish different EEG events, with very good classification accuracy. 2020-06-19T00:00:00Z https://repositorio.fleni.org.ar/xmlui/handle/123456789/280 Epilepsy seizure onset detection applying 1-NN classifier based on statistical parameters Zorgno, Ivanna; Blanc, María Cecilia; Oxenford, Simon; Gil Garbagnoli, Francisco; D’Giano, Carlos; Quintero Rincón, Antonio Epilepsy is a disease caused by an excessive discharge of a group of neurons in the cerebral cortex. Extracting this information using EEG signals is an ongoing challenge in biomedical signal processing. In this paper, a new method is proposed for onset seizure detection in epileptic EEG signals based on parameters from the t-location-scale distribution coupled with the variance and the Pearson correlation coefficient. The 1-nearest neighbor classifier achieved a 91% sensitivity (True positive rate) and 95% specificity (True Negative Rate) with a delay of 4.5 seconds (on average) in the 45 signals analyzed, which suggests that the proposed methodology is potentially useful for seizure onset detection in epileptic EEG signals. 2019-02-21T00:00:00Z https://repositorio.fleni.org.ar/xmlui/handle/123456789/275 Postencephalitic Epilepsy and Acute Symptomatic Seizures, in Infectious, Undetermined Etiology and Autoimmune Encephalitis (P4.5-028) Marone, Abril; Alessandro, Lucas; Ugarnes, Gabriela; Farez, Mauricio Franco Objective: To describe the encephalitis that have more frequently acute symptomatic seizures (ASS), type of seizures and development of postencephalitic epilepsy (PE). Background: Encephalitis is a frequent cause of symptomatic epilepsy. Patients who have acute symptomatic seizures (ASS) have a 10 and 22% risk of developing epilepsy in 5 and 20 years respectively. Patients with postencephalitic epilepsy (PE) have a worse prognosis. Design/Methods: Retrospective review of medical records of patients diagnosed with encephalitis between January-2006 and June-2018. Patients with previous epilepsy were excluded. The incidence of ASS, PE, clinical characteristics, complementary studies, treatment, and evolution was analyzed. For the comparison between groups, Chi square and Fisher tests were used for the categorical variables, and parametric and non-parametric methods for the continuous variables. Results: We included 130 patients with encephalitis, 46 infectious, 50 undetermined etiology and 34 autoimmune. 71% of the autoimmune patients presented ASS, being more frequent than the other etiologies (43% infectious and 58% undetermined etiology, p = 0.05). The autoimmune encephalitis presented a greater frequency of focal onset seizures to bilateral tonic-clonic, respect to the others (33% vs 7% undetermined etiology vs 10% infectious, p = 0.008). Patients with autoimmune encephalitis developed more PE than the others (24% vs 9% undetermined etiology and 6% infectious, p = 0.2). The most frequent seizures during the evolution of PE in autoimmune encephalitis were focal onset seizures with impaired awareness. Conclusions: In autoimmune encephalitis, a greater frequency of ASS was observed, manifested predominantly with focal onset seizures and evolved in a greater percentage of PE, compared with infectious and undetermined etiology encephalitis. From the findings observed, it would be important to determine and establish if the precociousness of the specific treatment of autoimmune encephalitis, could modify the evolution to PE. 2019-05-08T00:00:00Z