Speed tuning of direction repulsion describes an inverted U-function

Direction repulsion describes the phenomenon in which observers typically overestimate the direction difference between two superimposed motions moving in different directions (Marshak & Sekuler, Science 205(1979) 1399). Previous research has found that, when a relatively narrow range of distractor speeds is considered, direction repulsion of a target motion increases monotonically with increasing speed of the distractor motion. We sought to obtain a more complete measurement of this speed-tuning function by considering a wider range of distractor speeds than has previously been used. Our results show that, contrary to previous reports, direction repulsion as a function of distractor speed describes an inverted U-function. For a target of 2.5deg/s, we demonstrate that the attenuation of repulsion magnitude with high-speed disractors can be largely explained in terms of the reduced apparent contrast of the distractor. However, when we reduce target motion speed, this no longer holds. When considered from the perspective of Edwards et al.s (Edwards, Badcock, & Smith, Vision Research 38 (1998) 1573) two global-motion channels, our results suggest that direction repulsion is speed dependent when the distractor and target motions are processed by different globalmotion channels, but is not speed dependent when both motions are processed by the same, high-speed channel. The implications of these results for models of direction repulsion are discussed.

Green Party Factionalism. The Case of the Federation of Ecologists Alternatives, Greece

To date, the Federation of Ecologists Alternatives (FEA) is the only Greek green party to have achieved representation in Parliament. Based on written accounts of the period and in-depth interviews with the main protagonists, this article offers a theoretical explanation of FEA's short-lived trajectory (1989-92), describing it as a case of 'primordial factionalism': a case of intraparty factionalism stemming from externally imposed stresses rather than any internal debate about ideological purity (the classical Realo/Fundi conflict). The article maintains that in such cases, it is highly probable for an emerging green party to disintegrate during its formative period, thus adding a new perspective to classical green party factionalism theories.

Equalising opportunities for women in electoral politics in Ireland: The Views of Women Members of Parliament

This paper examines the attitudes of women political elites in Ireland toward positive action initiatives that would assist in increasing women's legislative presence. An earlier study isolated family responsibilities and lack of finance as significant barriers for Irish women wishing to enter, and stay in, political life. In addition, scholarly and policy debates on boosting women's parliamentary representation focus on manipulating electoral or party selection rules along with strategies for making a political career more compatible with women's socially determined responsibilities. This paper examines how Irish women politicians respond to various suggestions for positive action in these three arenas: combining legislative and family responsibilities, funding a political campaign and getting elected. The paper highlights the broad consensus among women politicians, irrespective of party, self-interest, or length of service, favoring certain positive action initiatives, as well as their reluctance to support other options. It also illustrates the complexity of implementing some of these reforms. In addition, the paper emphasizes how cultural expectations and values act to inhibit women's political agency.