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During the last years, it has been established that the prefrontal and posterior parietal brain lobes, which are mostly related to intelligence, have many connections to cerebellum. However, there is a limited research investigating cerebellum's relationship with cognitive processes. In this study, the network of cerebellum was analyzed in order to investigate its overall organization in individuals with low and high fluid Intelligence Quotient (IQ). Functional magnetic resonance imaging (fMRI) data were selected from 136 subjects in resting-state from the Human Connectome Project (HCP) database and were further separated into two IQ groups composed of 69 low-IQ and 67 high-IQ subjects. Cerebellum was parcellated into 28 lobules/ROIs (per subject) using a standard cerebellum anatomical atlas. Thereafter, correlation matrices were constructed by computing Pearson's correlation coefficients between the average BOLD time-series for each pair of ROIs inside the cerebellum. By computing conventional graph metrics, small-world network properties were verified using the weighted clustering coefficient and the characteristic path length for estimating the trade-off between segregation and integration. In addition, a connectivity metric was computed for extracting the average cost per network. The concept of the Minimum Spanning Tree (MST) was adopted and implemented in order to avoid methodological biases in graph comparisons and retain only the strongest connections per network. Subsequently, six global and three local metrics were calculated in order to retrieve useful features concerning the characteristics of each MST. Moreover, the local metrics of degree and betweenness centrality were used to detect hubs, i.e., nodes with high importance. The computed set of metrics gave rise to extensive statistical analysis in order to examine differences between low and high-IQ groups, as well as between all possible gender-based group combinations. Our results reveal that both male and female networks have small-world properties with differences in females (especially in higher IQ females) indicative of higher neural efficiency in cerebellum. There is a trend toward the same direction in men, but without significant differences. Finally, three lobules showed maximum correlation with the median response time in low-IQ individuals, implying that there is an increased effort dedicated locally by this population in cognitive tasks.

In this article, the presentation as well as the interpretation (in a historical framework) of the creation and development of the historiography of the Greek education from the foundation of the Modern Greek State to date was attempted. During the first decades after the liberation of Greece from the Turks, this historiography served the national ideology, emphasizing on methodological works. From the very beginning of the 20th century until 1974 (the period of the fall of the dictatorship excluded), historiography focused on event recording and undertook an educative role through a number of works which recorded events in a plenary, linear fashion. Over the last 35 years, historiography was obviously influenced by foreign trends, and it developed into new history, specifically, the interpretative history. This last change appeared in numerous works which, in addition to the description of events, attempted also to interpret them by correlating education with both the socio-political and the ideological-political conditions of the period. These works are influenced by the international trends in historiography such as the School of Annales, the Marxistic theories, the theories of reproduction, of dependence, etc. (Contains 14 footnotes.)

In this paper we attempt to show the educational argumentation of the Greek liberal political forces with respect to special education within the reform attempts that were undertaken in 1913, 1929, 1964, and 1985. More specifically, we detect the concepts that prevailed in each of the three main phases through which special education in Greece passed over the period under examination: a) the rejection and repulsion phase, b) the humanitarian treatment phase, and c) the recognition and participation-on-equal-terms phase. Finally, an attempt is made to interpret those perceptions of the liberal politicians regarding special education that dominated each time as viewed within the national-ideological framework that formulated them. (Contains 1 table.)

There have been several attempts to account for the impact of Mathematical Anxiety (MA) on brain activity with variable results. The present study examines the effects of MA on ERP amplitude during performance of simple arithmetic calculations and working memory tasks. Data were obtained from 32 university students as they solved four types of arithmetic problems (one- and two-digit addition and multiplication) and a working memory task comprised of three levels of difficulty (1,2,and 3-back task). Compared to the Low-MA group, High-MA individuals demonstrated reduced ERP amplitude at frontocentral (between 180-320 ms) and centroparietal locations (between 380-420 ms). These effects were independent of task difficulty/complexity, individual performance, and general state/trait anxiety levels. Results support the hypothesis that higher levels of self-reported MA are associated with lower cortical activation during the early stages of the processing of numeric stimuli in the context of cognitive tasks.