Graph analysis of verbal fluency test discriminate between patients with Alzheimer’s disease, Mild Cognitive Impairment and normal elderly controls

Verbal fluency is the ability to produce a satisfying sequence of spoken words during a given time interval. The core of verbal fluency lies in the capacity to manage the executive aspects of language. The standard scores of the semantic verbal fluency test are broadly used in the neuropsychological assessment of the elderly, and different analytical methods are likely to extract even more information from the data generated in this test. Graph theory, a mathematical approach to analyze relations between items, represents a promising tool to understand a variety of neuropsychological states. This study reports a graph analysis of data generated by the semantic verbal fluency test by cognitively healthy elderly (NC), patients with Mild Cognitive Impairment – subtypes amnestic(aMCI) and amnestic multiple domain (a+mdMCI) - and patients with Alzheimer’s disease (AD). Sequences of words were represented as a speech graph in which every word corresponded to a node and temporal links between words were represented by directed edges. To characterize the structure of the data we calculated 13 speech graph attributes (SGAs). The individuals were compared when divided in three (NC – MCI – AD) and four (NC – aMCI – a+mdMCI – AD) groups. When the three groups were compared, significant differences were found in the standard measure of correct words produced, and three SGA: diameter, average shortest path, and network density. SGA sorted the elderly groups with good specificity and sensitivity. When the four groups were compared, the groups differed significantly in network density, except between the two MCI subtypes and NC and aMCI. The diameter of the network and the average shortest path were significantly different between the NC and AD, and between aMCI and AD. SGA sorted the elderly in their groups with good specificity and sensitivity, performing better than the standard score of the task. These findings provide support for a new methodological frame to assess the strength of semantic memory through the verbal fluency task, with potential to amplify the predictive power of this test. Graph analysis is likely to become clinically relevant in neurology and psychiatry, and may be particularly useful for the differential diagnosis of the elderly.

Sociedade civil no espaço de atuação com juventude: uma cartografia social

This report has as its objective the setting up of a social cartography, mapping and characterizing non-governmental organizations working with adolescents and young people (OSC) in the western districts of the city of Natal. Characteristics such as the profile, themes and principal activities, how the organizations fit into the public sector and their participation in social networks are observed. Thus common differences and similarities which serve as a means of indentification, take as reference the symbolic cartography of Boaventura of Sousa Santos. Since there are relatively few studies relating to civil society of Rio Grande do Norte and in particular, Natal, the starting point was the setting up of a database allowing for a general overview. Hence a panorama of the organizations could be observed: where they are located, when they were formed how they operate and their relationships with other sectors (the state, the market and civil society) in addition to basic facts and location. The principal lines of enquiry were a) the OSC which operate with the public comprising adolescents and young people and b) the OSC operating or having branches in four suburbs on the periphery of the western administrative region of the city (Felipe Camarão, Bom Pastor, Cidade Nova and Guararapes).The present report has identified the impacts of ongoing social transformation caused by the process of globalization ,by the various currently contested political projects which are as follows: the project of neoliberal globalized capitalism(hegemonic)and the project of social emancipation (contra-hegemonic),how these are seen from the local viewpoint and how they influence the profiles and operation of the cartographic organizations. The area of the OSC is a heterogenous one with political, cultural and ideological strains, characterized by its infiltration, its local/global and multicultural dimensions. As civil organizations are fundamental in the processes of transformation within society, and following the idea of social emancipation referred to by Boaventura Santos, the enquiry classified the organizations according to the afore-mentioned characteristics, establishing eight types of associations. These different types and their respective characteristics were analysed from a related perspective using the mechanisms of symbolic cartography: scale, projection and symbolisation. The theoretical references underpinning this research arise from the debate on civil society which becomes redefined as a result of the dispute involving the two afore-mentioned political projects. These demand the theoretical application of the comprehension of heterogeneity in its diversity and complexity together with the idea of social emancipation.The main authors consulted were Boaventura de Sousa Santos, Antonio Gramsci, through the texts translated by Marco Aurelio Nogueira; Carlos Nelson Coutinho and Alberto Rivera ,who supported the construction of the types of associations identified by the local reality.Finally this research enabled an understanding of the current form of social action happening in the Space of the Four Neighbourhoods (Espaço dos 4 Bairros) and how the distinct profiles analysed together with the ares of operation of the organizations define their emancipatory potencials within the following two poles: regulation/adaptation and emancipation/transformation

Graph analysis of verbal fluency test discriminate between patients with Alzheimer’s disease, Mild Cognitive Impairment and normal elderly controls

Verbal fluency is the ability to produce a satisfying sequence of spoken words during a given time interval. The core of verbal fluency lies in the capacity to manage the executive aspects of language. The standard scores of the semantic verbal fluency test are broadly used in the neuropsychological assessment of the elderly, and different analytical methods are likely to extract even more information from the data generated in this test. Graph theory, a mathematical approach to analyze relations between items, represents a promising tool to understand a variety of neuropsychological states. This study reports a graph analysis of data generated by the semantic verbal fluency test by cognitively healthy elderly (NC), patients with Mild Cognitive Impairment – subtypes amnestic(aMCI) and amnestic multiple domain (a+mdMCI) - and patients with Alzheimer’s disease (AD). Sequences of words were represented as a speech graph in which every word corresponded to a node and temporal links between words were represented by directed edges. To characterize the structure of the data we calculated 13 speech graph attributes (SGAs). The individuals were compared when divided in three (NC – MCI – AD) and four (NC – aMCI – a+mdMCI – AD) groups. When the three groups were compared, significant differences were found in the standard measure of correct words produced, and three SGA: diameter, average shortest path, and network density. SGA sorted the elderly groups with good specificity and sensitivity. When the four groups were compared, the groups differed significantly in network density, except between the two MCI subtypes and NC and aMCI. The diameter of the network and the average shortest path were significantly different between the NC and AD, and between aMCI and AD. SGA sorted the elderly in their groups with good specificity and sensitivity, performing better than the standard score of the task. These findings provide support for a new methodological frame to assess the strength of semantic memory through the verbal fluency task, with potential to amplify the predictive power of this test. Graph analysis is likely to become clinically relevant in neurology and psychiatry, and may be particularly useful for the differential diagnosis of the elderly.