Medición de la voluntad de vivir en adultos mayores: adaptación transcultural, validez y confiabilidad de la Will-to-Live Scale / Measurement of the will to live in older adults: Transcultural adaptation, validity and reliability of the Will-to-Live Scale

OBJETIVO: La Will-to-Live Scale (WTLS) es utilizada para medir la voluntad de vivir en adultos mayores; sin embargo, no existe una versión en español. El objetivo del estudio fue traducir la WTLS al español, evaluar su estructura interna, su confiabilidad y los correlatos entre la WTLS y la satisfacción con la vida, la resiliencia y la depresión en adultos mayores peruanos. MÉTODO: Los participantes fueron 235 adultos mayores peruanos (M=72,69, DE=6,68) evaluados entre marzo y mayo de 2019, seleccionados a través de un muestreo no probabilístico. Se administró la WTLS, la Satisfaction with Life Scale (SWLS), la Brief Resilient Coping Scale (BRCS) y el Patient Health Questionnarie-2 (PHQ-2). El análisis de datos incluyó confiabilidad por consistencia interna y modelos de ecuaciones estructurales, específicamente el análisis factorial confirmatorio (AFC), para probar la solución unidimensional de la WTLS y la validez convergente de la WTLS a nivel latente, al especificar un modelo de cuatro factores (voluntad de vivir, satisfacción con la vida, resiliencia y depresión). RESULTADOS: El coeficiente alfa de Cronbach y el índice de confiabilidad compuesto obtienen valores de 0,93 y 0,94, respectivamente. La estructura unidimensional de la WTLS se ajustó a los datos (χ2(5)=10,067, p = 0,073, CFI=0,999, RMSEA=0,066, SRMR=0,014) y mostró asociaciones positivas con la SWLS (ρ=0,82) y la BRCS (ρ=0,86), así como negativa con el PHQ-2 (ρ=−0,66). CONCLUSIÓN: La WTLS en español presenta evidencias de validez y confiabilidad para medir la voluntad de vivir en adultos mayores peruanos

OBJECTIVE: The Will-to-Live Scale (WTLS) is used to measure the will to live in older adults; however, there is no Spanish version. The objective of the study was to translate the WTLS into Spanish, assess its internal structure, reliability, and the correlates between WTLS and life satisfaction, resilience, and depression in older Peruvian adults. METHOD: The participants were 235 Peruvian older adults (M=72.69, SD=6.68), evaluated between March to May 2019, selected through non-probability sampling. The WTLS, the Satisfaction with Life Scale (SWLS), the Brief Resilient Coping Scale (BRCS) and the Patient Health Questionnaire-2 (PHQ-2) were administered. Data analysis included reliability by internal consistency and structural equation models, specifically confirmatory factor analysis (AFC), to test the one-dimensional solution of the WTLS and the convergent validity of the WTLS at the latent level, by specifying a four-factor model (will to live, life satisfaction, resilience and depression). RESULTS: Cronbach's alpha coefficient and the composite reliability index obtain values of .93 and .94, respectively. The one-dimensional structure of the WTLS was fitted to the data (χ2(5)=10,067, P=.073, CFI=.999, RMSEA=.066, SRMR=.014) and showed positive associations with the SWLS (ρ=.82), and BRCS (ρ=.86), as well as negative associations with the PHQ-2 (ρ=−.66). CONCLUSION: The WTLS in Spanish presents evidence of validity and reliability to measure the will to live in Peruvian older adults

Exploration of computational methods for classification of movement intention during human voluntary movement from single trial EEG.

OBJECTIVE: To explore effective combinations of computational methods for the prediction of movement intention preceding the production of self-paced right and left hand movements from single trial scalp electroencephalogram (EEG). METHODS: Twelve naïve subjects performed self-paced movements consisting of three key strokes with either hand. EEG was recorded from 128 channels. The exploration was performed offline on single trial EEG data. We proposed that a successful computational procedure for classification would consist of spatial filtering, temporal filtering, feature selection, and pattern classification. A systematic investigation was performed with combinations of spatial filtering using principal component analysis (PCA), independent component analysis (ICA), common spatial patterns analysis (CSP), and surface Laplacian derivation (SLD); temporal filtering using power spectral density estimation (PSD) and discrete wavelet transform (DWT); pattern classification using linear Mahalanobis distance classifier (LMD), quadratic Mahalanobis distance classifier (QMD), Bayesian classifier (BSC), multi-layer perceptron neural network (MLP), probabilistic neural network (PNN), and support vector machine (SVM). A robust multivariate feature selection strategy using a genetic algorithm was employed. RESULTS: The combinations of spatial filtering using ICA and SLD, temporal filtering using PSD and DWT, and classification methods using LMD, QMD, BSC and SVM provided higher performance than those of other combinations. Utilizing one of the better combinations of ICA, PSD and SVM, the discrimination accuracy was as high as 75%. Further feature analysis showed that beta band EEG activity of the channels over right sensorimotor cortex was most appropriate for discrimination of right and left hand movement intention. CONCLUSIONS: Effective combinations of computational methods provide possible classification of human movement intention from single trial EEG. Such a method could be the basis for a potential brain-computer interface based on human natural movement, which might reduce the requirement of long-term training. SIGNIFICANCE: Effective combinations of computational methods can classify human movement intention from single trial EEG with reasonable accuracy.

Reliability of surface electromyographic measurements from subjects with spinal cord injury during voluntary motor tasks.

In this study, the reliability of surface electromyographic data (root-mean-square) for volitional motor tasks drawn from a standardized protocol was assessed. For each motor task, 5 s epochs of data were analyzed with a new method to generate a measure called the voluntary response index (VRI). The VRI consists of two components, magnitude and similarity index (SI), that were separately analyzed for repeatability. We examined three repetitions of each of 10 volitional motor tasks in 69 subjects with spinal cord injury (American Spinal Injury Association [ASIA] Impairment Scale [AIS], classifications C and D: 34 AIS-C and 35 AIS-D) for short-term (within-day) reliability. In 6 of the 69 subjects (3 each, AIS-C and AIS-D), the entire study was repeated after 1 week and results were assessed for intermediate-term (1 week apart) reliability. The reliability of the method for voluntary motor tasks was assessed by intraclass correlation coefficient (ICC), analysis of variance, coefficient of variance, and Pearson's correlation. Good reliability was found for magnitude (ICC = 0.71-0.99, Pearson's r = 0.77-0.99) and for SI (ICC = 0.65-0.96, Pearson's r = 0.72-0.93) for three repeated tests (within-day). Significant difference was found for studies completed 1 week apart for magnitude (p = 0.02) but not for SI (p = 0.57). In addition, SI showed less variation than magnitude (p < 0.001). No significant difference of magnitude and SI between tasks was observed.

Sobre la afectación (II): valor, creencia y afectación / On the affectation (II): value, belief and affectation

En la segunda parte del trabajo trataremos sobre las afectaciones (consecuencia de los sucesos psíquicos) en su relación con los valores, las creencias y los procesos de deliberación (AU)

Initial on-line evaluations of the LF-ASD brain-computer interface with able-bodied and spinal-cord subjects using imagined voluntary motor potentials.

Previous research has focused on developing a brain-controlled switch named the low frequency asynchronous switch design (LF-ASD) that is suitable for intermittent control of devices such as environmental control systems, computers, and neural prostheses. On-line implementations of the LF-ASD have shown promising results in response to actual index finger flexions with able-bodied subjects. This paper reports the results of initial on-line evaluations of the LF-ASD brain-controlled switch with both able-bodied subjects and subjects with high-level spinal-cord injuries. This paper has demonstrated that users can activate the LF-ASD switch by imaging movement. In this paper, two able-bodied subjects were able to control the LF-ASD with imagined voluntary movements with hit (true positive) rates above 70% and false positive rates below 3% while two subjects with high-level spinal-cord injuries demonstrated hit rates ranging from 45-48% and false positive rates below 1%.

The concurrent validity of a classification of dieters with low versus high susceptibility toward failure of restraint.

It has been experimentally shown that the population of high restrained eaters consists of two subpopulations, i.e., those with a low and those with a high susceptibility toward failure of restraint. Only those who combined high restraint with high scores on the disinhibition scale of the TFEQ (Three-Factor Eating Questionnaire) showed overeating after a preload. The aim of the present study was to assess the concurrent validity of a two-factorial classification using the Dutch Eating Behavior Questionnaire (DEBQ) scales for restraint, emotional and external eating, as well as the bulimia scale of the Eating Disorder Inventory (EDI) for locating dieters with low or high susceptibility toward failure. It was examined whether the resulting two-group classification is associated with self-reported behaviors and features of psychopathology, which are generally thought to differentiate both groups of dieters. The results indicated that the two-group classification was indeed associated with many of these behaviors and features of psychopathology. It was concluded that this classification has a good concurrent validity.

The selective breakdown of frontal functions in patients with obsessive-compulsive disorder and in patients with schizophrenia: a double dissociation experimental finding.

In an our recent preliminary study, we reported the neuropsychological finding of a double dissociation in the frontal lobe functioning between 25 OCD patients and 25 schizophrenics. The first group performed normally in the Wisconsin Card Sorting Test (WCST), which is considered sensitive to Dorso-Lateral Prefrontal Cortex (DLPFC) dysfunctions and abnormally to the Object Alternation Test (OAT), which has been proposed as a tool sensitive to Orbito-Frontal Cortex (OFC); on the other hand, schizophrenics performed abnormally to the WCST and normally to the OAT. The present study, conducted on a new sample of 60 schizophrenic in-patients, 60 OCD in-patients and 30 normal subjects, matched according to age, educational level, handedness and duration of illness, confirms our preliminary data and it suggests a more selective impairment of OFC system in OCD and of DLPFC in schizophrenia. Moreover, schizophrenic patients with paranoid subtype showed worse WCST performance compared to non-paranoid subtype. Our results could open some interesting perspectives about the neuroanatomical systems involved in these two major psychiatric illnesses and so, about their pharmacological treatment, on the basis of the prominent catecholaminergic characterization of the DLPFC and, respectively, the cholinergic innervation of the OFC.