Comparison of native and non-native phone imitation by english and spanish speakers

Experiments investigating phonetic convergence in conversation often focus on interlocutors with similar phonetic inventories. Extending these experiments to those with dissimilar inventories requires understanding the capacity of speakers to imitate native and non-native phones. In the present study, we tested native Spanish and native English speakers to determine whether imitation of non-native tokens differs qualitatively from imitation of native tokens. Participants imitated a [ba]–[pa] continuum that varied in VOT from −60 ms (prevoiced, Spanish [b]) to +60 ms (long lag, English [p]) such that the continuum consisted of some tokens that were native to Spanish speakers and some that were native to English speakers. Analysis of the imitations showed two critical results. First, both groups of speakers demonstrated sensitivity to VOT differences in tokens that fell within their native regions of the VOT continuum (prevoiced region for Spanish and long lag region for English). Secondly, neither group of speakers demonstrated such sensitivity to VOT differences among tokens that fell in their non-native regions of the continuum. These results show that, even in an intentional imitation task, speakers cannot accurately imitate non-native tokens, but are clearly flexible in producing native tokens. Implications of these findings are discussed with reference to the constraints on convergence in interlocutors from different linguistic backgrounds.Research was supported by grant FFI2009-13416-C02-02 to M. Pilar Aivar and by NIDCD grant R15DC011875-01 to Navin Viswanathan

Las teorías de la percepción visual y el problema del movimiento ocular

Desde la Antigüedad existían dos explicaciones de la percepción visual enfrentadas: las basadas en la idea de la «intra-misión» y las que defendían la idea de la «extra-misión» (Lindberg, 1976). Las primeras consideraban que la percepción visual ocurría gracias a una «efluencia» de carácter material, emitida por el objeto, que entraba en contacto con el ojo. Las segundas, sin embargo, consideraban que la visión se producía gracias a una «emanación», procedente del ojo, que capturaba las características del objeto al entrar en contacto con él. Las diferencias entre ambos planteamientos se extendían también a otros aspectos: mientras que las teorías de la intramisión entendían la percepción como proceso pasivo-receptivo, las teorías de la extramisión insistían en el papel activo del ojo en el proceso visual. El triunfo histórico de las teorías de la intramisión, a través de la idea de la imagen retiniana desarrollada por Kepler, supuso, a su vez, la aceptación generalizada del carácter pasivo de la sensación. Sin embargo, esta asunción de pasividad ha planteado problemas contínuamente en el estudio de aquellos aspectos de la percepción más ligados a la acción, como los movimientos oculares. En este trabajo describiremos la evolución histórica de estos dos tipos de teorías de la visión e intentaremos relacionar los problemas que subyacen a la discusión entre ambos tipos de teorías con la aparición en el momento actual de algunas propuestas teóricas que pretenden re-introducir la acción en el ámbito de la percepciónThere were two kinds of theories of vision in Antiquity: «intromission theories» and «extramission theories» (Lindberg, 1976). Theories in the first group considered that vision ocurred through some kind of effluence coming into the eye from objects, while those in the second group assumed that from the eye itself emanated some kind of visual power which was able to capture the characteristics of the objects that it encountered. Both kinds of theories were also different in other important aspects: in a sense intromission theories defended a passive-receptive conception of visual perception, while extramission theories insisted on the active role of the eye in the perceptual process. Kepler’s work and his development of the idea of the retinal image led to the historical success of intromission theories and therefore to the general acceptance of a passive conception of sensation. However this passivity asumption has been problematic for the study of vision, especially in those areas of research more closely related with action, like eye movements. In this article we will describe the historical development of both kinds of theories of vision. We will also try to relate the theoretical aspects beneath the opposition between both kinds of theories with recent efforts to recover action for the understanding of perceptionTrabajo financiado por el Ministerio de Educación y Ciencia (proyectos SEJ2005-09110-C03-02 y HUM2006-11603-C02-02

Correcting slightly less simple movements.

Many studies have analysed how goal directed movements are corrected in
 response to changes in the properties of the target. However, only simple
 movements to single targets have been used in those studies, so little is
 known about movement corrections under more complex situations.
 Evidence from studies that ask for movements to several targets in sequence
 suggests that whole sequences of movements are planned together. Planning
 related segments of a movement together makes it possible to optimise the
 whole sequence, but it means that some parts are planned quite long in
 advance, so that it is likely that they will have to be modified. In the present
 study we examined how people respond to changes that occur while they are
 moving to the first target of a sequence. Subjects moved a stylus across a
 digitising tablet. They moved from a specified starting point to two targets
 in succession. The first of these targets was always at the same position but
 it could have one of two sizes. The second target could be in one of two
 different positions and its size was different in each case. On some trials the
 first target changed size, and on some others the second target changed size
 and position, as soon as the subject started to move. When the size of the
 first target changed the subjects slowed down the first segment of their
 movements. Even the peak velocity, which was only about 150 ms after the
 change in size, was lower. Beside this fast response to the change itself, the
 dwell time at the first target was also affected: its duration increased after the
 change. Changing the size and position of the second target did not influence
 the first segment of the movement, but also increased the dwell time. The
 dwell time was much longer for a small target, irrespective of its initial size.
 If subjects knew in advance which target could change, they moved faster
 than if they did not know which could change. Taken together, these results
 suggest that the whole sequence is treated as one action, which can be
 corrected if the properties of any of the targets change. The precise nature and
 timing of the correction depends on how the change influences the task

Surface Expression and Subunit Specific Control of Steady Protein Levels by the Kv7.2 Helix A-B Linker

12 p.Kv7.2 and Kv7.3 are the main components of the neuronal voltage-dependent M-current, which is a subthreshold potassium conductance that exerts an important control on neuronal excitability. Despite their predominantly intracellular distribution, these channels must reach the plasma membrane in order to control neuronal activity. Thus, we analyzed the amino acid sequence of Kv7.2 to identify intrinsic signals that may control its surface expression. Removal of the interlinker connecting helix A and helix B of the intracellular C-terminus produces a large increase in the number of functional channels at the plasma membrane. Moreover, elimination of this linker increased the steady-state amount of protein, which was not associated with a decrease of protein degradation. The magnitude of this increase was inversely correlated with the number of helix A - helix B linkers present in the tetrameric channel assemblies. In contrast to the remarkable effect on the amount of Kv7.2 protein, removal of the Kv7.2 linker had no detectable impact on the steady-state levels of Kv7.3 protein.This work was supported by grants from the VII European framework program managed by the Fondo de Investigaciones Sanitarias (PI071316), from the Spanish Ministry of Education (BFU2009-07581 and SAF2006-1450), the Spanish Ion Channel Initiative Consolider project (CSD2008-00005), and the Basque Government (SAIOTEK SA-2006/00023). A. Alaimo was partially funded by Fundacion Biofisica Bizkaia. PA and JFO held a FPI fellowship from the Spanish Ministry of Science and Innovation (BES-2008-002314). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip