369 research outputs found

    An Event Related Potentials Study of the Effects of Age, Load and Maintenance Duration on Working Memory Recognition

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    Age-related decline in cognitive capacities has been attributed to a generalized slowing of processing speed and a reduction in working memory (WM) capacity. Nevertheless, it is unclear how age affects visuospatial WM recognition and its underlying brain electrical activity. Whether age modulates the effects of memory load or information maintenance duration, which determine the limits of WM, remains also elusive. In this exploratory study, performance in a delayed match to sample task declined with age, particularly in conditions with high memory load. Event related potentials analysis revealed longer N2 and P300 latencies in old than in young adults during WM recognition, which may reflect slowing of stimulus evaluation and classification processes, respectively. Although there were no differences between groups in N2 or P300 amplitudes, the latter was more homogeneously distributed in old than in young adults, which may indicate an age-related increased reliance in frontal vs parietal resources during WM recognition. This was further supported by an age-related reduced posterior cingulate activation and increased superior frontal gyrus activation revealed through standardized low resolution electromagnetic tomography. Memory load and maintenance duration effects on brain activity were similar in both age groups. These behavioral and electrophysiological results add evidence in support of age-related decline in WM recognition theories, with a slowing of processing speed that may be limited to stimulus evaluation and categorization processes -with no effects on perceptual processes- and a posterior to anterior shift in the recruitment of neural resourcesThis work was financially supported by the Ministerio de Educación (BES 2008-005929) and Ministerio de Economía y Competitividad (PSI2010-22224-C03-03), Gobierno de España; and by the Consellería de Economía e Industria (10 PXIB 211070 PR), and Consellería de Educación e Ordenación Universitaria (Ref: GPC 2014/047), Xunta de Galicia. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscriptS

    Effects of load and maintenance duration on the time course of information encoding and retrieval in working memory: from perceptual analysis to post-categorization processes

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    Working memory (WM) involves three cognitive events: information encoding, maintenance, and retrieval; these are supported by brain activity in a network of frontal, parietal and temporal regions. Manipulation of WM load and duration of the maintenance period can modulate this activity. Although such modulations have been widely studied using the event-related potentials (ERP) technique, a precise description of the time course of brain activity during encoding and retrieval is still required. Here, we used this technique and principal component analysis to assess the time course of brain activity during encoding and retrieval in a delayed match to sample task. We also investigated the effects of memory load and duration of the maintenance period on ERP activity. Brain activity was similar during information encoding and retrieval and comprised six temporal factors, which closely matched the latency and scalp distribution of some ERP components: P1, N1, P2, N2, P300, and a slow wave. Changes in memory load modulated task performance and yielded variations in frontal lobe activation. Moreover, the P300 amplitude was smaller in the high than in the low load condition during encoding and retrieval. Conversely, the slow wave amplitude was higher in the high than in the low load condition during encoding, and the same was true for the N2 amplitude during retrieval. Thus, during encoding, memory load appears to modulate the processing resources for context updating and post-categorization processes, and during retrieval it modulates resources for stimulus classification and context updating. Besides, despite the lack of differences in task performance related to duration of the maintenance period, larger N2 amplitude and stronger activation of the left temporal lobe after long than after short maintenance periods were found during information retrieval. Thus, results regarding the duration of maintenance period were complex, and future work is required to test the time-based decay theory predictionsThis study was funded by the Spanish Government: Ministerios de Educación (BES 2008-005929) and Economía y Competitividad (PSI2010-22224-C03-03); and by the Galician Government: Consellería de Economía e Industria (10 PXIB 211070 PR), and Consellería de Educación e Ordenación Universitaria (Axudas para a Consolidación e Estruturación de unidades de investigación competitivas do sistema universitario de Galicia. Ref: CN 2012/033)S

    Análisis Cualitativo de la fecundidad y participación femenina en el mercado de trabajo

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    Con frecuencia vemos en el aumento de las tasas de actividad femenina la consecuencia de una cierta independencia entre la evolución de la fecundidad y participación laboral femenina. En este trabajo trataremos de ver cómo esta inferencia es abusiva. El exámen de los datos españoles correspondentes al período 1977-1985 sugiere, una cierta estabilidad de la fecundiad frente a una actividad determinada. Trataremos de interpretar esta evolución con la ayuda de un sencillo modelo de comportamiento con tres parámetros : la valoración media de la actividad laboral, familia numerosa y un índice de incompatibilidad entre la actividad laboral y la función del cuidado y atención de los hijos. Comprobaremos que son las variaciones del primero de estos tres parámetros, las que mejor pueden explicar las ligadas a la actividad y fecundidad

    Working memory load modulates oscillatory activity and the distribution of fast frequencies across frontal theta phase during working memory maintenance

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    Working memory (WM) is a keystone of our cognitive abilities. Increasing load has been shown to dampen its performance and affect oscillatory neural activity in different frequency bands. Nevertheless, mixed results regarding fast frequencies activity and a lack of research on WM load modulations of cross-frequency phase-amplitude coupling mechanisms preclude a better understanding of the impact of increased WM load levels on brain activity as well as inter-regional communication and coordination supporting WM processes. Hence, we analyzed the EEG activity of 25 participants while performing a delayed-matching-to-sample (DMS) WM task with three WM load levels. Current density power and distribution at the source level for theta, beta, and gamma frequencies during the task's delay period were compared for each pair of WM load conditions. Results showed maximal increases of theta activity in frontal areas and of fast frequencies' activity in posterior regions with WM load, showing the involvement of frontal theta activity in WM maintenance and the control of attentional resources and visual processing by beta and gamma activity. To study whether WM load modulates communication between cortical areas, posterior beta and gamma amplitudes distribution across frontal theta phase was also analysed for those areas showing the largest significant WM load modulations. Higher beta activity amplitude at bilateral cuneus and right middle occipital gyrus, and higher gamma activity amplitude at bilateral posterior cingulate were observed during frontal theta phase peak in low than high memory load conditions. Moreover, greater fast beta amplitude at the right postcentral gyrus was observed during theta phase trough at right middle frontal gyrus in high than low memory load conditions. These results show that WM load modulates whether interregional communication occurs during theoretically optimal or non-optimal time windows, depending on the demands of frontal control of posterior areas required to perform the task successfullyThis study was supported by grants from the Spanish Government, Ministerio de Economía y Competitividad (PSI2014-55316-C3-3-R; PSI2017-89389-C2-2-R), with FEDER Funds; the Galician Government, Consellería de Cultura, Educación e Ordenación Universitaria, Axudas para a Consolidación e Estruturación de Unidades de Investigación Competitivas do Sistema Universitario de Galicia: GRC (GI-1807-USC); Ref: ED431-2017/27, with FEDER funds. D. P. was also supported by the Portuguese Foundation for Science and Technology (FCT) through the fellowship SFRH/BPD/120111/2016S

    The role of institutions in achieving radical innovation.

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    The purpose of this paper is to analyze how institutions can facilitate or inhibit radical innovation. The authors argue that organizational radical innovation is necessary to maintain a competitive advantage and to evolve in the market place, and institutions are the basis of this innovation. From an innovation and Service Dominant Logic perspective, network ties are proposed to be a determining factor for the achievement of innovation through institutionalization in the University knowledge management context.A conceptual approach is applied to develop and propose a framework for deepening understanding of radical organizational innovation, institutions and network ties. Data were gathered from Link by UMA-ATech, which in the context of the University of Málaga (Spain) is with great success developing a strategy based on fostering innovation. In all, 22 in-depth interviews were conducted with actors in the Link context, together with additional important second–order data analyses (sector analyses, statistics, company websites). Because of the perceived desirability of innovation, public universities have established a model as part of this strategy in order to foster and develop new businesses through technology transfer. Changing institutional arrangements is the basis of innovation. Opening universities to the actors around them, with an interest in exchanging resources through the evolution of network ties towards a less bureaucratic and more collaborative and open University (tertius iungens) is the basis for reaching organizational radical innovation in the university context to develop the provider-driven radical innovation network structure via the ‘University Living Lab’ theoretical model. A conceptual understanding is used in combination with an empirical approach, in which one case study and 22 organizations are considered in the context of Link-by-UMA ATech, at the University of Málaga

    Age-related effects on event-related brain potentials in a congruence/incongruence judgment color-word Stroop task

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    We examined the event-related brain potentials elicited by color-word stimuli in a Stroop task in which healthy participants (young and old) had to judge whether the meaning and the color of the stimulus were congruent or incongruent. The Stroop effect occurred in both age groups, with longer reaction times in the older group than in the young group for both types of stimuli, but no difference in the number of errors made by either group. Although the N2 and P3b latencies were longer in the older than in the younger group, there were no differences between groups in the latencies of earlier event-related potential components, and therefore the age-related processing slowing is not generalized. The frontal P150 amplitude was larger, and the parietal P3b amplitude was smaller, in the older than in the younger group. Furthermore, the P3b amplitude was maximal at frontal locations in older participants and at parietal locations in young participants. The age-related increase in perceptual resources and the posterior-to-anterior shift in older adults support adaptive reorganization of the neural networks involved in the processing of this Stroop-type taskThis study was financially supported by funds from the Spanish Government: Ministerio de Economía y Competitividad (PSI2010-22224-C03-03); and by the Galician Government: Consellería de Economía e Industria (10 PXIB 211070 PR), and Consellería de Cultura, Educación e Ordenación Universitaria (Axudas para a Consolidación e Estruturación de unidades de investigación competitivas do sistema universitario de Galicia. Ref: CN 2012/033; with FEDER funds)S

    Co-patenting, co-ownership, and co-ideation as drivers for university business innovation: the case of public universities in Spain

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    Purpose: This paper explores whether, in the context of university–industry (U–I) collaboration, new innovation strategies can be developed through actors' interactions, the exchange of resources and the co-creation of value for and within the system. In the context of the U–I relationship, the innovation perspective can highlight the need to develop strategies that elicit new formulas of value co-creation, which then facilitate innovation as a result of actor collaboration. Design/methodology/approach: A total of 45 public universities in Spain, representing 95% of the total, participated in qualitative research. Personal in-depth interviews with technology transfer officers (TTOs) were conducted by an external firm; in a second phase, two of the researchers conducted eight interviews with the directors of TTOs in those universities with higher rates of transfer. Findings: Findings reveal that enterprises with a technological focus are strengthening their relationships with universities and attempting to build a university business ecosystem by designing strategies for value co-creation such as co-ownership, co-patenting, and co-invention. Research limitations/implications: The empirical research is conducted in Spain, and results should be interpreted according to this context. Future research should examine new contexts (other countries) to improve the robustness of the data and enrich the results, thus enabling generalization of the management consequences. Originality/value: The results provide a means to design strategies under a new collaborative and innovating logic. The theoretical framework contributes to theory, with implications for management.The authors thank Gorka Artola, Ivan Martínez, Manel Arrufat, Xavier Vallvé, Jesús Banqueri, Antonio Peñafiel and Marina Rosales and all the universities in the sample for sharing their experience and knowledge in the development of the present research. // Funding for open access charge: Universidad de Málaga / CBU
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