Browsing by Author "Aboitiz, F."

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    Attention-deficit hyperactivity disorder involves differential cortical processing in a visual spatial attention paradigm
    (ELSEVIER IRELAND LTD, 2006) Lopez, V.; Lopez Calderon, J.; Ortega, R.; Kreither, J.; Carrasco, X.; Rothhammer, P.; Rothhammer, F.; Rosas, R.; Aboitiz, F.
    Objective: Inattention is undoubtedly one of the main characteristics of Attention-deficit hyperactivity disorder (ADHD). Nevertheless, a growing corpus of evidence shows that not all attentional processes are affected in this condition. This study aimed to explore the distribution of attentional resources in children with ADHD via a spatially shifted double-oddball visual task.
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    CHRONIC FLUOXETINE TREATMENT INDUCES STRUCTURAL PLASTICITY AND SELECTIVE CHANGES IN GLUTAMATE RECEPTOR SUBUNITS IN THE RAT CEREBRAL CORTEX
    (PERGAMON-ELSEVIER SCIENCE LTD, 2010) Ampuero, E.; Rubio, F. J.; Falcon, R.; Sandoval, M.; Diaz Veliz, G.; Gonzalez, R. E.; Earle, N.; Dagnino Subiabre, A.; Aboitiz, F.; Orrego, F.; Wyneken, U.
    It has been postulated that chronic administration of antidepressant drugs induces delayed structural and molecular adaptations at glutamatergic forebrain synapses that might underlie mood improvement. To gain further insight into these changes in the cerebral cortex, rats were treated with fluoxetine (flx) for 4 weeks. These animals showed decreased anxiety and learned helplessness. N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor subunit levels (NR1, NR2A, NR2B, GluR1 and GluR2) were analysed in the forebrain by both western blot of homogenates and immunohistochemistry. Both methods demonstrated an upregulation of NR2A, GluR1 and GluR2 that was especially significant in the retrosplenial granular b cortex (RSGb). However, when analysing subunit content in postsynaptic densities and synaptic membranes, we found increases of NR2A and GluR2 but not GluR1. Instead, GluR1 was augmented in a microsomal fraction containing intracellular membranes. NR1 and GluR2 were co-immunoprecipitated from postsynaptic densities and synaptic membranes. In the immunoprecipitates, NR2A was increased while GluR1 was decreased supporting a change in receptor stoichiometry. The changes of subunit levels were associated with an upregulation of dendritic spine density and of large, mushroom-type spines. These molecular and structural adaptations might be involved in neuronal network stabilization following long-term fix treatment. (C) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.
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    Theta and alpha oscillations may underlie improved attention and working memory in musically trained children
    (2024) Kausel, Leonie; Zamorano, F.; Billeke, P.; Sutherland, M. E.; Alliende, M. I.; Larrain-Valenzuela, J.; Soto-Icaza, P.; Aboitiz, F.
    Introduction: Attention and working memory are key cognitive functions that allow us to select and maintain information in our mind for a short time, being essential for our daily life and, in particular, for learning and academic performance. It has been shown that musical training can improve working memory performance, but it is still unclear if and how the neural mechanisms of working memory and particularly attention are implicated in this process. In this work, we aimed to identify the oscillatory signature of bimodal attention and working memory that contributes to improved working memory in musically trained children.Materials and methods: We recruited children with and without musical training and asked them to complete a bimodal (auditory/visual) attention and working memory task, whereas their brain activity was measured using electroencephalography. Behavioral, time-frequency, and source reconstruction analyses were made.Results: Results showed that, overall, musically trained children performed better on the task than children without musical training. When comparing musically trained children with children without musical training, we found modulations in the alpha band pre-stimuli onset and the beginning of stimuli onset in the frontal and parietal regions. These correlated with correct responses to the attended modality. Moreover, during the end phase of stimuli presentation, we found modulations correlating with correct responses independent of attention condition in the theta and alpha bands, in the left frontal and right parietal regions.Conclusions: These results suggest that musically trained children have improved neuronal mechanisms for both attention allocation and memory encoding. Our results can be important for developing interventions for people with attention and working memory difficulties.