7 documents found, page 1 of 1
Perceived cognitive functioning in breast cancer patients treated with chemothe...
Oliveira, A.F.; Torres, A.; Teixeira, R.J.; Monteiro, S.; Pereira, Anabela; Santos, I.M.Aim: Cognitive concerns are one of the most frequently reported symptoms by breast cancer survivors. This study aimed to evaluate perceived cognitive functioning in Portuguese women with breast cancer treated with chemotherapy. Methods: A cross-sectional study enrolling 146 women (73 with breast cancer and 73 healthy) was conducted from August to October 2017, invited to participate through online dissemination...
Mining EEG scalp maps of independent components related to HCT tasks
Teixeira, Ana; Santos, I.M.; Lang, E.W.; Tome, A.M.This work presents an unsupervised mining strat- egy, applied to an independent component analysis (ICA) of segments of data collected while participants are answering to the items of the Halstead Category Test (HCT). This new methodology was developed to achieve signal components at trial level and therefore to study signal dynamics which are not available within participants’ ensemble average signals. The stu...
ERP correlates of error processing during performance on the HalsteadCategory Test
Santos, I.M.; Teixeira, Ana; Tomé, A.M.; Pereira, A.T.; Rodrigues, P.; Vagos, P.; Costa, J.; Carrito, M.L.; Oliveira, B.; DeFilippis, N.A.; Silva, C.F.The Halstead Category Test (HCT) is a neuropsychological test that measures a person's ability to formulate and apply abstract principles. Performance must be adjusted based on feedback after each trial and errors are common until the underlying rules are discovered. Event-related potential (ERP) studies associated with the HCT are lacking. This paper demonstrates the use of amethodology inspired on Singular Sp...
Feature Extraction and Classification of Biosignals - Emotion Valence Detection...
Tomé, A. M.; Hidalgo-Muñoz, A.R.; López, M.M.; Teixeira, Ana; Santos, I.M.; Pereira, A.T.; Vázquez-Marrufo, M.; Lang, E.W.In this work a valence recognition system based on electroencephalograms is presented. The performance of the system is evaluated for two settings: single subjects (intra-subject) and between subjects (inter-subject). The feature extraction is based on measures of relative energies computed in short time intervals and certain frequency bands. The feature extraction is performed either on signals averaged over a...
SSA of biomedical signals: A linear invariant systems approach
Figueiredo, N.; Georgieva, P.; Lang, E.W.; Santos, I.M.; Teixeira, A.R.; Tomé, A.M.Singular spectrum analysis (SSA) is considered from a linear invariant systems perspective. In this terminology, the extracted components are considered as outputs of a linear invariant system which corresponds to finite impulse response (FIR) filters. The number of filters is determined by the embedding dimension.We propose to explicitly define the frequency response of each filter responsible for the selectio...
Clustering evoked potential signals using subspace methods
Tomé, A. M.; Teixeira, Ana; Figueiredo, N.; Georgieva, P.; Santos, I.M.; Lang, E.This work proposes a clustering technique to analyze evoked potential signals. The proposed method uses an orthogonal subspace model to enhance the single-trial signals of a session and simultaneously a subspace measure to group the trials into clusters. The ensemble averages of the signals of the different clusters are compared with ensemble averages of visually selected trials which are free of any artifact. ...
SSA of biomedical signals: A linear invariant systems approach
Tomé, A.M.; Teixeira, Ana Rita; Figueiredo, Nuno; Santos, I.M.; Georgieva, P.; Lang, E.W.Singular spectrum analysis (SSA) is considered from a linear invariant systems perspective. In this terminology, the extracted components are considered as outputs of a linear invariant system which corresponds to finite impulse response (FIR) filters. The number of filters is determined by the embedding dimension.We propose to explicitly define the frequency response of each filter responsible for the selectio...