A robust relationship between working memory (WM) and general intelligence (g) has been well established. Nevertheless, explanations for this relationship in terms of underlying neurocognitive processes are still inadequate. This study addresses this issue using an individual differences approach in which Central Executive System (CES) and Short-Term Storage (STS) components of WM are measured comprehensively and examined for their relationship with g via event-related potentials components (P200 and P300) as mediators. Participants (n = 115) completed tests of the WM, CES and STS, as well as g. P200 and P300 components were recorded during 3-back WM task performance. Structural equation modelling showed significant negative associations between the P200 latency for target stimuli and CES shifting processes, and between the P300 amplitude for target stimuli and CES inhibition and updating processes. The relationship between CES processes and g was mediated in a localized fashion by the P300 amplitude. These findings further support the notion that the CES has a multidimensional structure and, importantly, reveal that the inhibition and updating functions of the CES are crucial in explaining the relationship between WM and g. Negative relations between ERP indices (P200 latency and P300 amplitude for target stimuli) and g support a neural efficiency hypothesis related to high intelligence.

With the rapid growth of the older population globally, it is anticipated that age-related cognitive decline in the prodromal phase and more severe pathological decline will increase. Moreover, currently, no effective treatment options for the disease exist. Thus, early and timely prevention actions are promising and prior strategies to preserve cognitive functions by preventing symptomatology from increasing the age-related deterioration of the functions in healthy older adults. This study aims to develop the virtual reality-based cognitive intervention for enhancing executive functions (EFs) and examine the EFs after training with the virtual reality-based cognitive intervention in community-dwelling older adults. Following inclusion/exclusion criteria, 60 community-dwelling older adults aged 60–69 years were involved in the study and randomly divided into passive control and experimental groups. Eight 60 min virtual reality-based cognitive intervention sessions were held twice a week and lasted for 1 month. The EFs (i.e., inhibition, updating, and shifting) of the participants were assessed by using standardized computerized tasks, i.e., Go/NoGo, forward and backward digit span, and Berg’s card sorting tasks. Additionally, a repeated-measure ANCOVA and effect sizes were applied to investigate the effects of the developed intervention. The virtual reality-based intervention significantly improved the EFs of older adults in the experimental group. Specifically, the magnitudes of enhancement were observed for inhibitory as indexed by the response time, F(1) = 6.95, p .05, ηp2 = .11, updating as represented by the memory span, F(1) = 12.09, p .01, ηp2 = .18, and the response time, F(1) = 4.46, p = .04, ηp2 = .07, and shifting abilities as indexed by the percentage of correct responses, F(1) = 5.30, p = .03, ηp2 = .09, respectively. The results indicated that the simultaneous combined cognitive-motor control as embedded in the virtual-based intervention is safe and effective in enhancing EFs in older adults without cognitive impairment. Nevertheless, further studies are required to investigate the benefits of these enhancements to motor functions and emotional aspects relating to daily living and the well-being of older populations in communities. Ante el rápido crecimiento de la población mayor a nivel mundial se prevé un aumento del deterioro cognitivo propio de la edad en la fase prodrómica y un mayor deterioro patológico. Además no hay en la actualidad opciones eficaces de tratamiento de la enfermedad. Por tanto, las medidas preventivas tempranas y puntuales suponen estrategias prometedoras para preservar las funciones cognitivas al evitar que la sintomatología aumente el deterioro de las funciones asociado a la edad de personas mayores sanas. El presente estudio tiene como obejetivo desarrollar una intervención cognitiva basada en la realidad virtual para mejorar las funciones ejecutivas (FE) y examinarlas tras el entrenamiento de intervención cognitiva con realidad virtual en personas mayores que viven en su domicilio. Teniendo en cuenta criterios de inclusión y exclusión se contó para el estudio con 60 personas mayores de entre 60 y 69 años que vivían en su domicilio, a los que se asignó aleatoriamente a un grupo de control pasivo y a un grupo experimental. Se realizaron ocho sesiones de 60 minutos de intervención cognitiva con realidad virtual dos veces por semana durante un mes. Las FE (i.e., la inhibición, actualización y cambio) de los participantes se evaluaron mediante tareas informatizadas estandarizadas, i.e., Go/NoGo, amplitud de dígitos hacia delante y hacia atrás y clasificación de cartas de Berg. Además, se utilizó un ANCOVA de medidas repetidas y el tamaño del efecto para medir el efecto de la intervención desarrollada. La intervención con realidad virtual mejoró significativamente las funciones ejecutivas de los mayores del grupo experimental. En concreto se observaron más mejoras en inhibición, reflejada en el tiempo de respuesta, ,F,(1) = 6.95, ,p .05, η,p,2, = .11, actualización, representada por la amplitud de memoria, ,F,(1) = 12.09, ,p .01, η,p,2, = .18, y el tiempo de respuesta, ,F,(1) = 4.46, ,p, = .04, η,p,2, = .07, y las habilidades de cambio, como refleja el porcentaje de respuestas correctas, ,F,(1) = 5.30, ,p, = .03, η,p,2, = .09, respectivamente. Los resultados indican que el control cognitivo-motor combinado simultáneamente, tal y como se aplica en la intervención virtual, es seguro y eficaz para conseguir aumentar las funciones ejecutivas de personas mayores sin deterioro cognitivo. No obstante, se necesitan más estudios para investigar los beneficios de estas mejoras en las funciones motoras y los aspectos emocionales de la vida cotidiana, así como el bienestar de las personas mayores que viven en la comunidad.

Objective: The study investigated working memory, executive functions (conceptualized as response inhibition, updating, and shifting), and intelligence in schizophrenia, using structural equation modelling to determine the relationship between working memory and intelligence, testing whether specific executive functions act as a mediator for the association.Method: One hundred and twenty-five individuals diagnosed with schizophrenia and 64 healthy participants were included in the study, tested using measures of working memory, intelligence and executive functioning. Structural equation modelling (SEM) was used to estimate direct and indirect associations between main measures.Results: The schizophrenia group had significantly lower working memory, executive function and intelligence than the healthy group. The relationship between working memory and intelligence was significantly mediated by inhibition, updating and shifting functions.Conclusion: The study indicates a mediating role of executive functions in determining the association between working memory and intellectual function in schizophrenia. It is further proposed that in people with schizophrenia, cognitive remediation approaches targeting working memory through executive functioning may in turn improve intellectual function generally.