Categoría: Papers con abstracts

In the present work we analyzed the effect of contextual word predictability on the eye movement behavior of patients with mild Alzheimer disease (AD) compared to age-matched controls, by using the eyetracking technique and lineal mixed models. Twenty AD patients and 40 age-matched controls participated in the study. We first evaluated gaze duration during reading low and highly predictable sentences. AD patients showed an increase in gaze duration, compared to controls, both in sentences of low or high predictability. In controls, highly predictable sentences led to shorter gaze durations; by contrary, AD patients showed similar gaze durations in both types of sentences. Similarly, gaze duration in controls was affected by the cloze predictability of word N and N+1, whereas it was the same in AD patients. In contrast, the effects of word frequency and word length were similar in controls and AD patients. Our results imply that contextual-word predictability, whose processing is proposed to require memory retrieval, facilitated reading behavior in healthy subjects, but this facilitation was lost in early AD patients. This loss might reveal impairments in brain areas such as those corresponding to working memory, memory retrieval, and semantic memory functions that are already present at early stages of AD. In contrast, word frequency and length processing might require less complex mechanisms, which were still retained by AD patients. To the best of our knowledge, this is the first study measuring how patients with early AD process well-defined words embedded in sentences of high and low predictability. Evaluation of the resulting changes in eye movement behavior might provide a useful tool for a more precise early diagnosis of AD.

Methodological considerations regarding cognitive interventions in dementia. Autores Ibanez A, Richly P, Roca M, Manes F. Año 2014 Journal  Ibanez A, Richly P, Roca M, Manes F. Volumen 6:212. Abstract   Otra información  Las intervenciones cognitivas en la demencia son un aspecto esencial en la rehabilitación. Sin embargo sus efectos no han sido adecuadamente respaldados en la mayoría de las investigaciones … Leer más

La neuroeducación busca detectar problemas en las prácticas escolares y proponer soluciones guiadas por evidencia neurocognitiva. En este sentido, la acumulación de conocimientos sobre el cerebro bilingüe permite reflexionar sobre las propuestas de enseñanza de lenguas extranjeras. El presente artículo aborda dicha temática mediante una lectura crítica de los Diseños Curriculares (DCs) para la Educación Básica de la Provincia de Buenos Aires. Específicamente, se consideran hallazgos neurolingüísticos para analizar los DCs en lo concerniente a la enseñanza de la gramática inglesa y sugerir modificaciones generales para superar las inconsistencias advertidas.

Bridging psychiatry and neurology through social neuroscience. Autores Ibanez A, Kuljis R, Matallana D, Manes F.  Año 2014 Journal  Ibanez A, Kuljis R, Matallana D, Manes F.  Volumen 13(2): 148-149 Abstract   Otra información  En este trabajo se resalta el rol multinivel de la neurociencia social para construir puentes entre los cuadros psiquiátricos y neurológicos a través de la presentación de … Leer más

Los pacientes con lesiones de la ínsula (al igual que las de áreas frontales) presentan un desempeño muy variable respecto el reconocimiento de las emociones, la empatía y la cognición social, que va desde la total afección a la total preservación. Dicha variabilidad podría explicarse por neuroplasticidad, procesos compensatorios y remapeo funcional. En este trabajo proponemos que la conectividad efectiva y el modelo de predictive coding representan una nueva aproximación para comprender dicha variabilidad a partir de las conexiones direccionales con otras áreas.

Psychiatrists’ approach to vascular risk assessment in Latin America. Autores Richly P, López PL, Gleichgerrcht E, Flichtentrei D, M Prats, R Mastandueno, Bustin J, Cetkovich M.  Año 2014 Journal  Richly P, López PL, Gleichgerrcht E, Flichtentrei D, M Prats, R Mastandueno, Bustin J, Cetkovich M.  Volumen 4(3): 56-61 Abstract   Otra información    

Predictive theories of action observation propose that we use our own motor system as a guide for anticipating and understanding other people‟s actions through the generation of context-based expectations. According to this view, people should be better in predicting and interpreting those actions that are present in their own motor repertoire compared to those that are not. We recorded high-density event-related potentials (ERPs: P300, N400 and Slow Wave, SW) and source estimation in 80 subjects separated by their level of expertise (experts, beginners and naïves) as they observed realistic videos of Tango steps with different degrees of execution correctness. We also performed path analysis to infer causal relationships between ongoing anticipatory brain activity, evoked semantic responses, expertise measures and behavioral performance. We found that anticipatory justify activity, with sources in a fronto-parieto-occipital network, early discriminated between groups according to their level of expertise. Furthermore, this early activity significantly predicted subsequent semantic integration indexed by semantic responses (N400 and SW, sourced in temporal and motor regions) which also predicted motor expertise. In addition, motor expertise was a good predictor of behavioral performance. Our results show that neural and temporal dynamics underlying contextual action anticipation and comprehension can be interpreted in terms of successive levels of contextual prediction that are significantly modulated by subject‟s prior experience.

Objective: We studied theory of mind (ToM) in patients withmild relapsing-remitting multiple sclerosis (MS), seeking possibledissociations between its 2 components: cognitive ToM (theability to infer others intentions) and affective ToM (the abilityto infer others emotional states). We analyzed the relationshipof ToM to executive function, depression, and fatigue. Background: Dissociations between cognitive and affective ToMhave been found in several neurologic and neuropsychiatricdiseases. Most ToM studies in patients with MS have showngeneral ToM deficits but have not analyzed the cognitive andaffective aspects individually. Methods: We used the Faux Pas test of ToM and tests of executivefunction to assess 18 patients with mild relapsing-remittingMS and 16 control participants. Results: Our patients showed deficits in cognitive ToM, but theiraffective ToM seemed to be spared. Their cognitive ToM deficitswere not related to executive dysfunction, depression, or fatigue. Conclusions: Our study is the first differential analysis showingcognitive but not affective ToM deficits in mild relapsing-remittingMS. Further research is needed to determine the exactnature and the real impact of these deficits, and to establish theirrelationship with the neuropathology and progression of MS.

Previous single-case reports in Posterior Cortical Atrophy (PCA) have shown preserved non-conscious visual recognition despite the absence of explicit recognition. In this study we investigated three levels of visual recognition in both a female patient with PCA and a control group during the presentation of neutral, positive, and negative affective stimuli. Our results confirmed the profile of impaired explicit recognition and intact psychophysiological responses in the patient. In addition, she was able to implicitly recognize the valence and intensity of arousal of these stimuli. We suggest that implicit emotional awareness may mediates explicit and psychophysiological recognition in PCA.

Previous studies about personality changes in dementia suggest that they may be due to the disruption of the biological basis of personality traits, and hence, that they are disease specific and universal. However, evidence about its specificity is still limited and scarce regarding culturally diverse populations. Accordingly, our aim was to compare personality changes in Argentinean patients with Alzheimer disease, behavioral variant of frontotemporal dementia, and primary progressive aphasia. The closest living relatives of patients diagnosed with Alzheimer disease (n=19), behavioral variant of frontotemporal dementia (n=16), and primary progressive aphasia (n=15) were asked to complete 2 versions of the personality inventory NEO Personality Inventory-Revised, one for assessing patients’ premorbid personality traits, and the other for assessing current traits. All groups showed changes in several domains and facets of the NEO Personality Inventory-Revised. Globally, the observed pattern of changes was fairly consistent with previous studies based on the same model of personality. Nevertheless, our results regarding disease-specificity were less conclusive. Even if there were some indicators of specific differences between groups, most traits varied similarly across the 3 groups, revealing a pattern of generalized changes in personality expression after illness onset. More studies are needed that help to distinguish real personality changes from other affective or cognitive symptoms that accompany dementia, as well as further data from culturally diverse populations.