Grey and white matter correlates of recent and remote autobiographical memory retrieval:Insights from the dementias

The capacity to remember self-referential past events relies on the integrity of a distributed neural network. Controversy exists, however, regarding the involvement of specific brain structures for the retrieval of recently experienced versus more distant events. Here, we explored how characteristic patterns of atrophy in neurodegenerative disorders differentially disrupt remote versus recent autobiographical memory. Eleven behavioural-variant frontotemporal dementia, 10 semantic dementia, 15 Alzheimer's disease patients and 14 healthy older Controls completed the Autobiographical Interview. All patient groups displayed significant remote memory impairments relative to Controls. Similarly, recent period retrieval was significantly compromised in behavioural-variant frontotemporal dementia and Alzheimer's disease, yet semantic dementia patients scored in line with Controls. Voxel-based morphometry and diffusion tensor imaging analyses, for all participants combined, were conducted to investigate grey and white matter correlates of remote and recent autobiographical memory retrieval. Neural correlates common to both recent and remote time periods were identified, including the hippocampus, medial prefrontal, and frontopolar cortices, and the forceps minor and left hippocampal portion of the cingulum bundle. Regions exclusively implicated in each time period were also identified. The integrity of the anterior temporal cortices was related to the retrieval of remote memories, whereas the posterior cingulate cortex emerged as a structure significantly associated with recent autobiographical memory retrieval. This study represents the first investigation of the grey and white matter correlates of remote and recent autobiographical memory retrieval in neurodegenerative disorders. Our findings demonstrate the importance of core brain structures, including the medial prefrontal cortex and hippocampus, irrespective of time period, and point towards the contribution of discrete regions in mediating successful retrieval of distant versus recently experienced events

Intersection between metabolic dysfunction, high fat diet consumption, and brain aging

Deleterious neurochemical, structural, and behavioral alterations are a seemingly unavoidable aspect of brain aging. However, the basis for these alterations, as well as the basis for the tremendous variability in regards to the degree to which these aspects are altered in aging individuals, remains to be elucidated. An increasing number of individuals regularly consume a diet high in fat, with high‐fat diet consumption known to be sufficient to promote metabolic dysfunction, although the links between high‐fat diet consumption and aging are only now beginning to be elucidated. In this review we discuss the potential role for age‐related metabolic disturbances serving as an important basis for deleterious perturbations in the aging brain. These data not only have important implications for understanding the basis of brain aging, but also may be important to the development of therapeutic interventions which promote successful brain aging.Fil: Uranga, Romina Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; ArgentinaFil: Bruce Keller, Annadora J.. State University of Louisiana; Estados UnidosFil: Morrison, Christopher D.. State University of Louisiana; Estados UnidosFil: Fernandez Kim, Sun Ok. State University of Louisiana; Estados UnidosFil: Ebenezer, Philip J.. State University of Louisiana; Estados UnidosFil: Zhang, Le. State University of Louisiana; Estados UnidosFil: Dasuri, Kalavathi. State University of Louisiana; Estados UnidosFil: Keller, Jeffrey N.. State University of Louisiana; Estados Unido

Scope and limitations in the evaluation of programs for digital literacy in Latin America: A paradigmatic case. The ''Plan CEIBAL''

Este artículo, en primer lugar revisa el estado actual de los instrumentos de monitoreo de los programas de alfabetización digital en la región, y en segundo término, propone, a partir de una mirada crítica sobre las limitaciones que imponen los indicadores cuantitativos para la comprensión del alcance socio cultural de dichos programas, estrategias de evaluación cualitativa que tengan como premisa la recuperación de la perspectiva del actor, y en consecuencia, permitan, elaborar indicadores más comprensivos de la experiencia de apropiación de las TICs entre sus beneficiarios.This article reviews in the fi rst place the state of monitoring instruments for digital education programs in the region and secondly, it evaluates, from a critical perspective, the limitations imposed by quantitative indicators for the comprehension of the socio cultural scope of these programs. Qualitative evaluation strategies that recover the subject’s viewpoint enable the development of more comprehensive indicators of the experience of ICT appropriation for the benefi ciaries of these programs.Fil: Winocur, Rosalía. Universidad Autónoma Metropolitana; MéxicoFil: Aguerre Regusci, Carolina Inés. Universidad de San Andres. Centro de Tecnología y Sociedad; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Scope and limitations in the evaluation of programs for digital literacy in Latin America: A paradigmatic case. The ''Plan CEIBAL''

Este artículo, en primer lugar revisa el estado actual de los instrumentos de monitoreo de los programas de alfabetización digital en la región, y en segundo término, propone, a partir de una mirada crítica sobre las limitaciones que imponen los indicadores cuantitativos para la comprensión del alcance socio cultural de dichos programas, estrategias de evaluación cualitativa que tengan como premisa la recuperación de la perspectiva del actor, y en consecuencia, permitan, elaborar indicadores más comprensivos de la experiencia de apropiación de las TICs entre sus beneficiarios.This article reviews in the fi rst place the state of monitoring instruments for digital education programs in the region and secondly, it evaluates, from a critical perspective, the limitations imposed by quantitative indicators for the comprehension of the socio cultural scope of these programs. Qualitative evaluation strategies that recover the subject’s viewpoint enable the development of more comprehensive indicators of the experience of ICT appropriation for the benefi ciaries of these programs.Fil: Winocur, Rosalía. Universidad Autónoma Metropolitana; MéxicoFil: Aguerre Regusci, Carolina Inés. Universidad de San Andres. Centro de Tecnología y Sociedad; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

The influence of recollection and familiarity in the formation and updating of associative representations

Prior representations affect future learning. Little is known, however, about the effects of recollective or familiarity-based representations on such learning. We investigate the ability to reuse or reassociate elements from recollection- and familiarity-based associations to form new associations. Past neuropsychological research suggests that hippocampal, and presumably recollective, representations are more flexible than extra-hippocampal, presumably familiarity-based, representations. We therefore hypothesize that the elements of recollective associations, as opposed to familiarity-based representations, may be more easily manipulated and decoupled from each other, and facilitate the formation of new associations. To investigate this hypothesis we used the AB/AC learning paradigm. Across two recall studies we observed an advantage in learning AC word pairs if AB word pairs were initially recollected. Furthermore, AB word pairs were more likely to intrude during a final AC test if those AB word pairs were initially familiarity-based. A third experiment using a recognition version of the AB/AC paradigm ruled out the possibility that our findings were due to memory strength. Our results support the idea that elements in recollective associative traces may be more discretely coded, leading to their flexible use, whereas elements in familiarity-based associative traces are less flexible

Emerging pharmacotherapy for cancer patients with cognitive dysfunction

Advances in the diagnosis and multi-modality treatment of cancer have increased survival rates for many cancer types leading to an increasing load of long-term sequelae of therapy, including that of cognitive dysfunction. The cytotoxic nature of chemotherapeutic agents may also reduce neurogenesis, a key component of the physiology of memory and cognition, with ramifications for the patient's mood and other cognition disorders. Similarly radiotherapy employed as a therapeutic or prophylactic tool in the treatment of primary or metastatic disease may significantly affect cognition. A number of emerging pharmacotherapies are under investigation for the treatment of cognitive dysfunction experienced by cancer patients. Recent data from clinical trials is reviewed involving the stimulants modafinil and methylphenidate, mood stabiliser lithium, anti-Alzheimer's drugs memantine and donepezil, as well as other agents which are currently being explored within dementia, animal, and cell culture models to evaluate their use in treating cognitive dysfunction

Conflitos e diferenças geracionais no uso das tecnologias digitais

Neste artigo, Rosalía Winocur, doutora em Antropologia e professora da Universidade Autônoma Metropolitana do México, analisa os conflitos que surgem entre jovens e adultos, particularmente entre os primeiros e seus pais e professores, a partir das diferenças no manejo das tecnologias digitais. Segundo a autora, “os adultos procuram ‘domesticar' a tecnologia e os jovens se envolvem com elas”. Os adultos tem medo de cometer erros e perder o trabalho que realizam enquanto os jovens assumem os riscos como condição natural de viver e navegar na rede. Estas são algumas temáticas deste artigo que discute as distintas expectativas e representações de jovens e adultos sobre as tecnologias digitais. Leia mais