bioRxiv ScienceSearch

Biology subjects

Gracia-Tabuenca, Z.

Publications and source records attributed to Gracia-Tabuenca, Z..

2 recordsLinked to original sources

The Time Varying Networks of the Interoceptive Attention and Rest

Focused attention to spontaneous sensations is a phenomenon that demands interoceptive abilities and a dynamic character of attentive processes. The lack of its control has been linked to neuropsychiatric disorders, such as illness-anxiety disorder. Regulatory strategies, like focused attention meditation, may enhance the ability to control attention particularly to body sensations, which can be reflected on functional neuroanatomy. Adopting a systems-level approach, we aimed at estimating the recurring fMRI functional connectivity (FC) patterns between regions of the dorsal attention network, default mode network, and frontoparietal network during 20 minutes of an attentional task to spontaneous sensations (Task), and at rest, before (Pre-task rs) and after the task (Post-task rs), in fifteen experienced meditators. Dynamic functional connectivity analysis was performed using sliding windows and k-means clustering on the grouped data finding five FC patterns. In both rest conditions the subjects remain longer in a low connectivity state, in contrast, during the task a higher proportion of time spent in complex organization states was preferred. Moreover, an impact over the post-task rs FC was observed as an effect of the preceding interoceptive task performance, with this remaining effect probably taking an active role in the learning process linked to cognitive training.Competing Interest StatementThe authors have declared no competing interest.View Full Text

neuroscience

Topological Data Analysis reveals robust alterations in the whole-brain and frontal lobe functional connectomes in Attention-Deficit/Hyperactivity Disorder

The functional organization of the brain network (connectome) has been widely studied as a graph; however, methodological issues may affect the results, such as the brain parcellation scheme or the selection of a proper threshold value. Instead of exploring the brain in terms of a static connectivity threshold, this work explores its algebraic topology as a function of the filtration value (i.e., the connectivity threshold), a process termed the Rips filtration in Topological Data Analysis. Specifically, we characterized the transition from all nodes being isolated to being connected into a single component as a function of the filtration value, in a public dataset of children with attention-deficit/hyperactivity disorder (ADHD) and typically developing children. Results were highly congruent when using four different brain segmentations (atlases), and exhibited significant differences for the brain topology of children with ADHD, both at the whole brain network and at the functional sub-network levels, particularly involving the frontal lobe and the default mode network. Therefore, this approach may contribute to identify the neurophysio-pathology of ADHD, reducing the bias of connectomics-related methods.\n\nHighlightsO_LITopological Data Analysis was implemented in functional connectomes.\nC_LIO_LIBetti curves were assessed based on the area under the curve, slope and kurtosis.\nC_LIO_LIThe explored variables were robust along four different brain atlases.\nC_LIO_LIADHD showed lower areas, suggesting decreased functional segregation.\nC_LIO_LIFrontal and default mode networks showed the greatest differences between groups.\nC_LI\n\nGraphical Abstract\n\nO_FIG O_LINKSMALLFIG WIDTH=168 HEIGHT=200 SRC=\"FIGDIR/small/751008v1_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (51K):\norg.highwire.dtl.DTLVardef@50e91corg.highwire.dtl.DTLVardef@1f837aforg.highwire.dtl.DTLVardef@10fe920org.highwire.dtl.DTLVardef@1923ead_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience