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Research on the biological basis of autism spectrum disorder has yielded a list of brain abnormalities that are arguably as diverse as the set of behavioral symptoms that characterize the disorder. Among these are patterns of abnormal cortical connectivity and abnormal basal ganglia development. In attempts to integrate the existing literature, the current paper tests the hypothesis that impairments in the basal ganglia's function to flexibly select and route task-relevant neural signals to the prefrontal cortex underpins patterns of abnormal synchronization between the prefrontal cortex and other cortical processing centers observed in individuals with autism spectrum disorder (ASD). We tested this hypothesis using a Dynamic Causal Modeling analysis of neuroimaging data collected from 16 individuals with ASD (mean age=25.3 years; 6 female) and 17 age- and IQ-matched neurotypical controls (mean age=25.6, 6 female), who performed a Go/No-Go test of executive functioning. Consistent with the hypothesis tested, a random-effects Bayesian model selection procedure determined that a model of network connectivity in which basal ganglia activation modulated connectivity between the prefrontal cortex and other key cortical processing centers best fit the data of both neurotypicals and individuals with ASD. Follow-up analyses suggested that the largest group differences were observed for modulation of connectivity between prefrontal cortex and the sensory input region in the occipital lobe [ t (31)=2.03, p =0.025]. Specifically, basal ganglia activation was associated with a small decrease in synchronization between the occipital region and prefrontal cortical regions in controls; however, in individuals with ASD, basal ganglia activation resulted in increased synchronization between the occipital region and the prefrontal cortex. We propose that this increased synchronization may reflect a failure in basal ganglia signal gating mechanisms, resulting in a non-selective copying of signals to prefrontal cortex. Such a failure to prioritize and filter signals to the prefrontal cortex could result in the pervasive impairments in cognitive flexibility and executive functioning that characterize autism spectrum disorder, and may offer a mechanistic explanation of some of the observed abnormalities in patterns of cortical synchronization in ASD. [ABSTRACT FROM AUTHOR]

Abstract: As the process of deregulation of the electric utility industry proceeds, the importance of power quality is increasing. A fundamental aspect of power quality is the continuity of power supply that is the absence of momentary, temporary and sustained power interruptions. In this paper a network reconfiguration strategy is proposed which allows the distribution network to separate into a certain number of autonomous islands, supplied by local distributed generation, in case of permanent fault within the grid. Intentional islanding of portions of the grid is automatically carried out with an adaptive network reconfiguration depending upon the local generation/load state at the time of outage. [Copyright &y& Elsevier]

Mounting evidence suggests that bilingual development may change the brain in a way that gives rise to differences in non-linguistic cognitive functioning; however, only a limited number of studies have investigated the mechanism by which bilingualism shapes the brain. The current study used a network-level analysis to investigate differences in the mechanisms by which bilinguals and monolinguals flexibly adapt their neural networks in the face of novel task demands. Three competing hypotheses concerning differences in network-level adaptation were examined using Dynamic Causal Modeling of data from 15 bilinguals and 14 monolinguals who performed a Rapid Instructed Task Learning paradigm. The results demonstrated that the best-fitting model for the data from both groups specified that novel task execution is accomplished through a modulation of the influence of the anterior cingulate cortex (ACC) on the dorsolateral prefrontal cortex (DLPFC) and on the striatum. Further examination of the best-fitting model revealed that ACC activity increased DLPFC and striatal activity in bilinguals but decreased activity in these regions in monolinguals. Interestingly, an increased positive connection between the ACC and striatum was associated with decreased accuracy across groups. Taken together, the results suggest that regardless of language experience, the ACC plays a critical role in cognitive flexibility, but the exact influence of the ACC on other primary control regions seems to be dependent on language experience. When paired with the behavioral results, these results suggest that bilinguals and monolinguals may employ different neurocognitive mechanisms for conflict monitoring to flexibly adapt to novel situations. [ABSTRACT FROM AUTHOR]

The methodologies of cognitive architectures and functional magnetic resonance imaging can mutually inform each other. For example, four modules of the ACT-R (adaptive control of thought – rational) cognitive architecture have been associated with four brain regions that are active in complex tasks. Activity in a lateral inferior prefrontal region reflects retrieval of information in a declarative module; activity in a posterior parietal region reflects changes to problem representations in an imaginal module; activity in the anterior cingulate cortex reflects the updates of control information in a goal module; and activity in the caudate nucleus reflects execution of productions in a procedural module. Differential patterns of activation in such central regions can reveal the time course of different components of complex cognition. [Copyright &y& Elsevier]