Neural Representations for Sensory-Motor Control I: Head-Centered 3-D Target Positions from Opponent Eye Commands

This article describes how corollary discharges from outflow eye movement commands can be transformed by two stages of opponent neural processing into a head-centered representation of 3-D target position. This representation implicitly defines a cyclopean coordinate system whose variables approximate the binocular vergence and spherical horizontal and vertical angles with respect to the observer's head. Various psychophysical data concerning binocular distance perception and reaching behavior are clarified by this representation. The representation provides a foundation for learning head-centered and body-centered invariant representations of both foveated and non-foveated 3-D target positions. It also enables a solution to be developed of the classical motor equivalence problem, whereby many different joint configurations of a redundant manipulator can all be used to realize a desired trajectory in 3-D space.

Representations of Catholicism in selected works by Colm Tóibín

The aim of this thesis is to provide an original and extensive study of Colm Tóibín as the “secular revisionist who acknowledges Catholicism as an enduring element of Irish society” (Ryan, Ireland and Scotland 251). Tóibín is uniquely placed to interpret many aspects of Ireland in the latter half of the twentieth century and I will argue that intertwined with his revisionism of Irish history is a reimagining of Ireland and Catholicism in fictive terms. An extensive amount of material from Tóibín’s time as a journalist and travel writer will feature in my research because it validates my argument concerning his prolonged engagement with Catholicism. Similarly, a broad range of Tóibín’s prose will be studied because it affords opportunities for an exploration of a literary Catholic oeuvre in his fiction. Therefore, I am emphasizing that a crucial linkage of Catholicism is identifiable throughout Tóibín’s diverse canon of work. However, I will argue that divergences of attitude and mode can be found in how Tóibín depicts Catholicism in his journalism and fiction. My argument identifies Tóibín’s recurrent journalistic questioning of the Church’s teaching and leadership but I classify a benignity towards Catholicism in his travel writing and fiction. Overall, Tóibín’s fiction merits significant status in this thesis because of the representations of Catholicism in the work of a writer who has been short-listed three times for The Booker Prize.

Locating the transnational: representations and aesthetics of the city in contemporary European cinemas

This thesis focuses on two Western European cinematic cities, and two unique periods of their respective nations’ histories, in a bid to “locate” the transnational within a contemporary European milieu. I argue that my geo-cinematic case studies are emblematic of broader questions of the problematics of national identity in contemporary Europe in the face of cross-national flows yet, as a result of their representations as cities both “anchored” and “in flux”, they reject a European postnational identity. Through its engagement with cinematic Rome as the “Eternal City” of Europe and cinematic Dublin as the “newly Europeanised” city, my thesis traces how representations and aesthetics of the urban spaces of these two cities correspond with the tensions at the heart of the respective eras in question. Via the figures that inhabit it, navigate it and search for it, the city is utilised to highlight fixity and mobility, centrality and dislocation, in explicit and implicit ways, amid the rapidly changing landscape of its national terrain. It is through my analyses of the filmed places and sociopolitical, socioeconomic and sociocultural spaces of these capital cities under the rubric of the transnational that this research demonstrates the “pluralities” of the construct in its cinematic manifestations. It is also my aim to evaluate the concept of cinematic transnationalism when identifying and accounting for representations of a specific national, historical timeframe, when the momentousness of the changes that occur is not bound by the national, but rather is reflective of the influence of both domestic and external forces. To this end, my thesis draws attention to instances in which the nation is shown to persist and resist dilution, arguing that it is only against the backdrop and continuity of the nation (in its evershifting guises) that the transnational can be conceived in representative and aesthetic terms.

Imaging Learned Song Representations in Populations of Sensorimotor Neurons Essential to Vocal Communication

Perceiving or producing complex vocalizations such as speech and birdsongs require the coordinated activity of neuronal populations, and these activity patterns can vary over space and time. How learned communication signals are represented by populations of sensorimotor neurons essential to vocal perception and production remains poorly understood. Using a combination of two-photon calcium imaging, intracellular electrophysiological recording and retrograde tracing methods in anesthetized adult male zebra finches (Taeniopygia guttata), I addressed how the bird's own song and its component syllables are represented by the spatiotemporal patterns of activity of two spatially intermingled populations of projection neurons (PNs) in HVC, a sensorimotor area required for song perception and production. These experiments revealed that neighboring PNs can respond at markedly different times to song playback and that different syllables activate spatially intermingled HVC PNs within a small region. Moreover, noise correlation analysis reveals enhanced functional connectivity between PNs that respond most strongly to the same syllable and also provides evidence of a spatial gradient of functional connectivity specific to PNs that project to song motor nucleus (i.e. HVC_RA cells). These findings support a model in which syllabic and temporal features of song are represented by spatially intermingled PNs functionally organized into cell- and syllable-type networks.

The role of technology in the study of semiotic representations in mathematics

En este trabajo resumimos algunas reflexiones sobre el papel que pueden desarrollar la tecnología en el estudio de sistemas semióticos de representación, y que constituyen el núcleo para la comprensión de los procesos de construcción del conocimiento matemático de los estudiantes. La cita corresponde con el resumen de una página publicado.

Representations of multicultural identities in British Cinema

This paper explores the transnational and interstitial dimensions of cultural production in Britain today, and the representation of migrant and diasporic identities in contemporary mainstream British cinema. The box office success of films like Gurindha Chadha’s Bhaji on the Beach (1993) and Bend it Like Beckham (2002) and East is East (Daniel O’Donnell 1999) and their precursors My Beautiful Launderette (Stephen Frears 1985), Sammy and Rosie Get Laid (Stephen Frears 1987) and the TV mini-series Buddha of Suburbia (Roger Mitchell 1993) seem to celebrate and articulate a set of values around hybridity and alterity: a discourse of multiculturalism. This paper will engage with a series of key questions. Are there ideological values implicit within and common to all these texts? Can we map a rhetoric or discourse of multiculturalism within popular culture? Do mainstream representations of immigrant identities represent a discourse of resistance, a decolonising global culture or is this Western brand of multiculturalism still located within an Orientalising gaze? In what ways are multiculturalism and postcolonialism overlapping and yet opposing rhetorics? [From the Author]

Conditional cash transfer programs and the representations of poverty in Bolivia and Peru

Bolivia and Peru adopted the same instruments of social policy —conditional cash transfer programs— to solve the same public problems under different political regimes. By means of the qualitative methodology of discourse analysis, this paper studies the representations of poverty and State made by key actors of those social programs. Underlying more differences than similarities, one demonstrates that the same social policy is linked to opposite social representations of poverty and the State role in every country. The main explanation for this is, far from being imposed by international organizations, those programs are adopted and adapted by each political regime.