resting-state condition), two different brain networks, the default mode network (DMN), and the dorsal visuo-spatial attention system, , show decreased activity in AD patients compared to age-matched healthy subjects (, but see also ). In the absence of goal-directed behavior (i.e. In AD, both selective decreases and increases in brain activity have been reported in a variety of behavioral conditions. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Ĭompeting interests: The authors have declared that no competing interests exist.Īlzheimer disease (AD) has been characterized as a disconnection syndrome ( for AD for age-related cognitive decline), implying network-wide functional changes due to local structural changes. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.įunding: The data acquisition was supported by the Institute for the Study of Aging ( grant 231002) and Netherlands Organization for Scientific Research ( grant 916.36.117). Received: DecemAccepted: JPublished: November 1, 2010Ĭopyright: © 2010 Sanz-Arigita et al. Breitner, University of Washington, United States of America (2010) Loss of ‘Small-World’ Networks in Alzheimer's Disease: Graph Analysis of fMRI Resting-State Functional Connectivity. This effectively translates in a global reduction of functional long-distance links between frontal and caudal brain regions.Ĭitation: Sanz-Arigita EJ, Schoonheim MM, Damoiseaux JS, Rombouts SARB, Maris E, Barkhof F, et al. Post-hoc analysis of the regional synchronization reveals increased AD synchronization involving the frontal cortices and generalized decreases located at the parietal and occipital regions. The whole-brain average synchronization does not differ between Alzheimer and healthy control groups. Compared to controls, the characteristic path length of AD functional networks is closer to the theoretical values of random networks, while no significant differences were found in cluster coefficient. Local (cluster coefficient) and global (path length) network measures were quantitatively defined. Functional coupling between brain regions was calculated on the basis of pair-wise synchronizations between regional time-series. All rights reserved.18 mild AD patients and 21 healthy age-matched control subjects without memory complaints were investigated in resting-state condition with MRI at 1.5 Tesla. Our hope is that children with pica will receive early intervention to prevent pica from developing into life-threatening behavior.Ĭopyright © 2012 Elsevier Ltd. Our hope is that administrators, professionals and practitioners will consider our guidelines and recommendations as they attempt to protect people with pica and developmental disabilities from harm by developing standards for assessment, treatment and prevention for this difficult-to-treat population. These recommendations are based on two extensive reviews of the literature and our extensive experience as practitioners in the treatment of pica. We make recommendations for assessment, treatment, and prevention of pica for practitioners.

A second limitation of current research is that some studies reduced pica substantially, but pica responses still occurred at rates that are problematic in terms of prevention of adverse consequences, which leaves practitioners with the task of further decreasing pica to protect people exhibiting pica from harm. While a number of published studies have demonstrated that pica behavior can be decreased substantially with behavioral treatment, few of these studies incorporated strategies for generalization and maintenance outside of brief sessions. Studies also indicate that pica has led to the death of people with developmental disabilities. Pica is a dangerous form of self-injurious behavior that occurs in people with developmental disabilities who are institutionalized.

Pica treatment graphs