Exploring inter-trial coherence for inner speech classification in EEG-based brain-computer interface.

Objective. In recent years, electroencephalogram (EEG)-based brain-computer interfaces (BCIs) applied to inner speech classification have gathered attention for their potential to provide a communication channel for individuals with speech disabilities. However, existing methodologies for this task fall short in achieving acceptable accuracy for real-life implementation. This paper concentrated on exploring the possibility of using inter-trial coherence (ITC) as a feature extraction technique to enhance inner speech classification accuracy in EEG-based BCIs.Approach. To address the objective, this work presents a novel methodology that employs ITC for feature extraction within a complex Morlet time-frequency representation. The study involves a dataset comprising EEG recordings of four different words for ten subjects, with three recording sessions per subject. The extracted features are then classified using k-nearest-neighbors (kNNs) and support vector machine (SVM).Main results. The average classification accuracy achieved using the proposed methodology is 56.08% for kNN and 59.55% for SVM. These results demonstrate comparable or superior performance in comparison to previous works. The exploration of inter-trial phase coherence as a feature extraction technique proves promising for enhancing accuracy in inner speech classification within EEG-based BCIs.Significance. This study contributes to the advancement of EEG-based BCIs for inner speech classification by introducing a feature extraction methodology using ITC. The obtained results, on par or superior to previous works, highlight the potential significance of this approach in improving the accuracy of BCI systems. The exploration of this technique lays the groundwork for further research toward inner speech decoding.

Prostatectomía radical de salvamento: Experiencia Hospital Militar Central / Rescue radical prostatectomy: Experience Central Military Hospital

La prostatectomía radical de salvamento viene siendo usada como tratamiento con intención curativa en aquellos pacientes que cursan con recaída bioquímica local luego de radioterapia1. En el Hospital Militar Central se ha realizado rutinariamente este procedimiento desde 1999 para aquellos pacientes que no poseen coomorbilidades, con una expectativa de vida mayor a 10 años y con enfermedad localizada. A diferencia de las publicaciones, en nuestra experiencia las complicaciones intraoperatorias han sido pocas. Por lo cual recomendamos este tipo de procedimiento con fines curativos.