Effects of Video Game Training on Behavioral and Electrophysiological Measures of Attention and Memory: Protocol for a Randomized Controlled Trial.

BACKGROUND: Neuroplasticity-based approaches seem to offer promising ways of maintaining cognitive health in older adults and postponing the onset of cognitive decline symptoms. Although previous research suggests that training can produce transfer effects, this study was designed to overcome some limitations of previous studies by incorporating an active control group and the assessment of training expectations. OBJECTIVE: The main objectives of this study are (1) to evaluate the effects of a randomized computer-based intervention consisting of training older adults with nonaction video games on brain and cognitive functions that decline with age, including attention and spatial working memory, using behavioral measures and electrophysiological recordings (event-related potentials [ERPs]) just after training and after a 6-month no-contact period; (2) to explore whether motivation, engagement, or expectations might account for possible training-related improvements; and (3) to examine whether inflammatory mechanisms assessed with noninvasive measurement of C-reactive protein in saliva impair cognitive training-induced effects. A better understanding of these mechanisms could elucidate pathways that could be targeted in the future by either behavioral or neuropsychological interventions. METHODS: A single-blinded randomized controlled trial with an experimental group and an active control group, pretest, posttest, and 6-month follow-up repeated measures design is used in this study. A total of 75 cognitively healthy older adults were randomly distributed into experimental and active control groups. Participants in the experimental group received 16 1-hour training sessions with cognitive nonaction video games selected from Lumosity, a commercial brain training package. The active control group received the same number of training sessions with The Sims and SimCity, a simulation strategy game. RESULTS: We have recruited participants, have conducted the training protocol and pretest assessments, and are currently conducting posttest evaluations. The study will conclude in the first semester of 2017. Data analysis will take place during 2017. The primary outcome is transfer of benefit from training to attention and working memory functions and the neural mechanisms underlying possible cognitive improvements. CONCLUSIONS: We expect that mental stimulation with video games will improve attention and memory both at the behavioral level and in ERP components promoting brain and mental health and extending independence among elderly people by avoiding the negative personal and economic consequences of long-term care. TRIAL REGISTRATION: Clinicaltrials.gov NCT02796508; https://clinicaltrials.gov/ct2/show/NCT02796508 (archived by WebCite at http://www.webcitation.org/6nFeKeFNB).

Expanding the occupational health methodology: A concatenated artificial neural network approach to model the burnout process in Chinese nurses.

Artificial neural networks are sophisticated modelling and prediction tools capable of extracting complex, non-linear relationships between predictor (input) and predicted (output) variables. This study explores this capacity by modelling non-linearities in the hardiness-modulated burnout process with a neural network. Specifically, two multi-layer feed-forward artificial neural networks are concatenated in an attempt to model the composite non-linear burnout process. Sensitivity analysis, a Monte Carlo-based global simulation technique, is then utilised to examine the first-order effects of the predictor variables on the burnout sub-dimensions and consequences. Results show that (1) this concatenated artificial neural network approach is feasible to model the burnout process, (2) sensitivity analysis is a prolific method to study the relative importance of predictor variables and (3) the relationships among variables involved in the development of burnout and its consequences are to different degrees non-linear. PRACTITIONER SUMMARY: Many relationships among variables (e.g., stressors and strains) are not linear, yet researchers use linear methods such as Pearson correlation or linear regression to analyse these relationships. Artificial neural network analysis is an innovative method to analyse non-linear relationships and in combination with sensitivity analysis superior to linear methods.

Psychological distance and reaction time in a Stroop task.

Several sources of interference may simultaneously affect the onset of the well-known "Stroop effect." Among them is the semantic component, which is reflected in the gradient or semantic effect. This effect consists of an increase in the amount of interference as the semantic distance between the word and the color concept decreases. Shepard (Science 237:1317-1323, 1987) relates psychological space, measured through multidimensional scaling, to mean response times. The present investigation aims to study the function relating the semantic gradient with the psychological distance between the word and the color in a Stroop task. After measuring the gradient, we obtained the subjective rating of the degree of dissimilarity of the gradient words with the concept of "color." In our work, we show that the amount of interference in a Stroop task increases when the semantic distance from the word to the color concept decreases, and it does so exponentially. We replicated the study with different stimuli to test the robustness of the results.

El envejecimiento afecta a las pruebas de compleción de raíces y reconocimiento pero no a la generación de categorías / Aging affects word-stem completion and recognition but not category generation

En este estudio investigamos el efecto de la edad en dos tareas de memoria implícita, la prueba de compleción de raíces y la de generación de categorías, y comparamos la actuación de jóvenes y mayores en estas pruebas con la actuación en una prueba de memoria explícita (reconocimiento ‘antiguo-nuevo’). Nuestra predicción fue que los jóvenes actuarían mejor que los mayores en la prueba de reconocimiento, mientras que ambos grupos mostrarían efectos de priming similar en ambas pruebas de memoria implícita. Los resultados mostraron: (a) en los dos grupos de edad hubo priming en ambas tareas de memoria implícita; (b) los jóvenes mostraron más priming que los mayores en la tarea de compleción de raíces, mientras el priming fue similar en ambos grupos en la tarea de generación de categorías; y (c) los jóvenes actuaron mejor que los mayores en la prueba de memoria explícita. Estos resultados no solo mostraron disociación entre las tareas de memoria implícita y explícita, sino también entre dos tareas de memoria implícita (AU)

In this study, we investigated the effect of aging on two implicit memory tasks, word-stem completion and category generation, and on explicit recognition. We compared the performance of young and older adults on these implicit memory tasks with those of explicit recognition. We expected better performance of young than older adults in the explicit memory task and similar priming in both implicit memory tasks. The results showed that young adults performed better than older adults in the recognition task. Moreover, both age groups showed priming in the implicit memory tasks, although priming was greater in young adults compared to older adults in the word-stem completion memory task, whereas both age groups showed similar levels of priming in the category generation task. The present results showed dissociations as a function of age not only between the explicit and the implicit tasks but also between the implicit tasks (AU)

Evaluación de tres medidas de la sensibilidad en tareas de estimación de magnitudes / Evaluation of three sensitivity measures in magnitude estimation tasks

Considerando la literatura experimental sobre la medida de la sensibilidad en tareas de estimación de magnitudes, en este trabajo analizamos las tres medidas de la sensibilidad más utilizadas, que son: el coeficiente de correlación de Pearson (R) entre el logaritmo del estímulo y el logaritmo de la respuesta, el exponente de la ecuación potencial de Stevens (K) y la medida «M» propuesta por Garriga-Trillo. Utilizando una muestra amplia (180 participantes), dos tipos de estímulo (segmentos y cuadrados) y modificando el rango estimular (ancho y estrecho), se descartó el uso de K como medida de la sensibilidad, porque los resultados que ofrece al comparar dos rangos estimulares son contrarios a los esperados. También se descartó el uso de M porque es una transformación lineal del coeficiente de correlación tau de Kendall. Finalmente, se comprobó que aplicando a la medida R la transformación matemática propuesta por Fisher se logra una distribución normal, siendo esta transformación la que se consideró como una medida de la sensibilidad más adecuada en la aplicación de estimación de magnitudes

Taking into account the studies about the measure of sensitivity in magnitude estimation tasks, we analyze the three most common measures used in this topic: Pearson’s product-moment correlation between the logarithm of the stimulus and the logarithm of the response (R), the exponent of Stevens’ power function (K), and the measure "M" proposed by Garriga-Trillo. Using a sample of participants greater than usual in psychophysical studies (180 participants), we designed an experiment with two sets of stimuli with different stimulus ranges. In each of these sets, we used two kinds of stimuli (line segments and squares). Our conclusions were: (1) we rejected the use of K as a sensitivity measure because the results provided by this index were the opposite of those expected when we compared the two stimulus ranges. (2) We also rejected the use of M because this measure is a linear transformation of Kendall’s coefficient of concordance. (3) Lastly, we suggest the mathematical transformation proposed by Fisher to achieve a normal distribution, and recommend this transformation as the best sensitivity measure

[Evaluation of three sensitivity measures in magnitude estimation tasks]. / Evaluación de tres medidas de la sensibilidad en tareas de estimación de magnitudes.

Taking into account the studies about the measure of sensitivity in magnitude estimation tasks, we analyze the three most common measures used in this topic: Pearson's product-moment correlation between the logarithm of the stimulus and the logarithm of the response (R), the exponent of Stevens' power function (K), and the measure "M" proposed by Garriga-Trillo. Using a sample of participants greater than usual in psychophysical studies (180 participants), we designed an experiment with two sets of stimuli with different stimulus ranges. In each of these sets, we used two kinds of stimuli (line segments and squares). Our conclusions were: (1) we rejected the use of K as a sensitivity measure because the results provided by this index were the opposite of those expected when we compared the two stimulus ranges. (2) We also rejected the use of M because this measure is a linear transformation of Kendall's coefficient of concordance. (3) Lastly, we suggest the mathematical transformation proposed by Fisher to achieve a normal distribution, and recommend this transformation as the best sensitivity measure.