Rehabilitation of reading in older individuals with macular degeneration: a review of effective training programs

Macular degeneration (MD) is the most common cause of visual impairment among older adults. It severely affects reading performance. People with MD have to rely on peripheral vision for reading. In this review, we considered several training programs that aim to improve peripheral reading, with a focus on eccentric viewing, oculomotor control, or perceptual learning. There was no strong support in favor of one particular training method for rehabilitation of reading in MD, but there is evidence that older individuals with MD can be trained to improve reading performance, even within limited time.     

Hursthouse’s Virtue Ethics and Abortion: Abortion Ethics without Metaphysics?

This essay explicates and evaluates the roles that fetal metaphysics and moral status play in Rosalind Hursthouse’s abortion ethics. It is motivated by Hursthouse’s puzzling claim in her widely anthologized paper “Virtue Ethics and Abortion” that fetal moral status and (by implication) its underlying metaphysics are “in a way, fundamentally irrelevant” to her position. The essay clarifies the roles that fetal ontology and moral status do in fact play in her abortion ethics. To this end, it presents and then develops her fetal metaphysics of the potential and actual human being, which she merely adumbrates in her more extensive treatment of abortion ethics in her book Beginning Lives. The essay then evaluates her fetal ontology in light of relevant research on fetal neural and psychological development. It concludes that her implied view that the late-stage fetus is an actual human being is defensible. The essay then turns to the analysis of late-stage abortions in her paper and argues that it is importantly incomplete.     

Portuguese-Canadian Emigrant Descendents in Multicultural Canada: Ambiguous Identity in a Sure-Footed Nation or Cultural Awareness in an Uncertain Country?

This paper examines the ways the descendents of Portuguese-Canadian immigrants contemplate and formulate their identities. Through qualitative, open-ended interviews, the research demonstrates how these individuals contest ideas of ‘being Portuguese’ and ‘being Canadian’ within the frameworks of the Canadian multicultural policy. Refusing to be positioned outside the nation and Anglo/Francophone conformity, these individuals produce their own meanings of identity by working through their own personally identified multiethnic bodies to the national body politic, where some of them see their own selves as intrinsically ‘multicultural’ and contributors to the very definition of a Canadian identity. Challenging the tropes of the Canadian multicultural narrative, these descendents, thus, develop nuanced models of cultural citizenship, illustrating that national identities are formed and transformed in relation to representation. Through the process of narrative analysis, my endeavour of this article are twofold: on one hand, to illuminate the role of these individuals who, as active actors, are shaped by the social worlds they delve in and, on the other, to explicate how the roles played out by these actors can contribute to the construction of ‘a Canadian identity’.     

Identification with community‐based HIV agencies as a correlate of turnover intentions and general self‐efficacy

Research (e.g. French, Power, & Mitchell, 2000 ; Harris, 2006 ; Harris & Alderson, 2006 , 2007 ; Roy & Cain, 2001 ) has highlighted important benefits for people living with HIV/AIDS to become connected with HIV community‐based (CB) agencies (e.g. reduction of isolation, educational opportunities, empowerment). However, CB HIV organizations sometimes experience challenges in recruiting and retaining people living with HIV/AIDS. In a sample of 68 respondents associated with a Canadian HIV/AIDS CB agency, facets of agency identification were examined as correlates of (a) turnover intentions with the agency and (b) aspects of psychological adjustment (hope and general self‐efficacy). Results indicated one dimension of social identification, in‐group affect, as a significant correlate of turnover intentions (such that members with more positive agency‐derived feelings were more likely to say they would stay at the agency), and another emotionally‐relevant aspect of identification, in‐group ties, as a significant correlate of general self‐efficacy. Hope was unrelated to social identification. Several implications for HIV CB agencies are discussed. Copyright © 2010 John Wiley & Sons, Ltd.     

Contemporary theories of 1/f noise in motor control

1/f noise has been discovered in a number of time series collected in psychological and behavioral experiments. This ubiquitous phenomenon has been ignored for a long time and classical models were not designed for accounting for these long-range correlations. The aim of this paper is to present and discuss contrasted theoretical perspectives on 1/f noise, in order to provide a comprehensive overview of current debates in this domain. In a first part, we propose a formal definition of the phenomenon of 1/f noise, and we present some commonly used methods for measuring long-range correlations in time series. In a second part, we develop a theoretical position that considers 1/f noise as the hallmark of system complexity. From this point of view, 1/f noise emerges from the coordination of the many elements that compose the system. In a third part, we present a theoretical counterpoint suggesting that 1/f noise could emerge from localized sources within the system. In conclusion, we try to draw some lines of reasoning for going beyond the opposition between these two approaches.     

Processing of contour closure by baboons (Papio papio)

This study investigated the Gestalt law of closure in baboons. Using a computer-controlled self-testing procedure, we trained baboons (Papio papio) to discriminate open versus closed shapes presented on a touch screen with a two-alternative forced choice procedure. Ten baboons (OPEN + group) were trained with the open shapes serving as the positive stimulus (S+), and nine others (CLOSE + group) were trained with the closed shape serving as S+. The OPEN + group obtained higher discrimination performance than the CLOSE + group (Exp 1), but its scores declined when new line segments were added to the stimuli (Exp 2) and after smoothing the end points of the open shapes (Exp 3). The CLOSE + group was less affected by the above manipulations of local stimulus dimension, but its performance was disrupted when the collinearity end points was reduced (Exp 3). Use of a visual search task revealed that the search for an open shape among closed distractors was less attention demanding in baboons than the search for a closed shape among open ones (Exp 4). It is concluded that (1) end lines rather than closeness per se are perceptual primitives for the open versus closed discrimination in baboons, and (2) the relative emphasis on local or configural cues when processing contour closure depends on experiential factors in baboons and is thus subject to interindividual variations.     

Interpersonal distance regulates functional grouping tendencies of agents in team sports

The authors examined whether, similar to collective agent behaviors in complex, biological systems (e.g., schools of fish and colonies of ants), performers in team sports displayed functional coordination tendencies, based on local interaction rules during performance. To investigate this issue, they used videogrammetry and digitizing procedures to observe interpersonal interactions in common 4 versus 2 + 2 subphases of the team sport of rugby union, involving 16 participants aged between 16 and 17 years of age. They observed pattern-forming dynamics in attacking subunits (n = 4 players) attempting to penetrate 2 defensive lines (n = 2 players in each). Data showed that within each attacking subunit, the 4 players displayed emergent functional grouping tendencies that differed between the 2 defensive lines. Results confirmed that grouping tendencies in attacking subunits of team games are sensitive to different task constraints, such as relative positioning to nearest defenders. It was concluded that running correlations were particularly useful for measuring the level of interpersonal coordination in functional grouping tendencies within attacking subunits.     

How useful are landmarks when learning a route in a virtual environment? Evidence from typical development and Williams syndrome

The ability to learn a route through a virtual environment was assessed in 19 older children and adults with Williams syndrome (WS) and 40 typically developing (TD) children aged 6-9 years. In addition to comparing route-learning ability across groups, we were interested in whether participants show an adult-like differentiation between "useful" and "less useful" landmarks when learning a route and the relative salience of landmark position versus landmark identity. Each virtual environment consisted of a brick wall maze with six junctions. There were 16 landmarks in the maze, half of which were on the correct path and half on incorrect paths. Results showed that both groups could learn each route to criterion (two successful completions of a route without error). During the learning phase, the WS group produced more errors than the TD group and took longer to reach criterion. This was predominantly due to the large number of perseverative errors (i.e., errors that were made at the same choice point on consecutive learning trials) made by the WS group relative to the TD children. We suggest that this reflects a difficulty in inhibiting erroneous responses in WS. During the test phase, the TD group showed stronger recall of landmarks adjacent to junctions (more useful landmarks) than of landmarks along path sections (less useful landmarks) independent of each individual's level of nonverbal ability. This pattern was also evident in the WS group but was related to level of nonverbal maturation; the differentiation between recall of junction and path landmarks increased as nonverbal ability increased across WS participants. Overall, the results demonstrate that individuals with WS can learn a route but that the development of this ability is atypical.     

Approximate entropy normalized measures for analyzing social neurobiological systems

When considering time series data of variables describing agent interactions in social neurobiological systems, measures of regularity can provide a global understanding of such system behaviors. Approximate entropy (ApEn) was introduced as a nonlinear measure to assess the complexity of a system behavior by quantifying the regularity of the generated time series. However, ApEn is not reliable when assessing and comparing the regularity of data series with short or inconsistent lengths, which often occur in studies of social neurobiological systems, particularly in dyadic human movement systems. Here, the authors present two normalized, nonmodified measures of regularity derived from the original ApEn, which are less dependent on time series length. The validity of the suggested measures was tested in well-established series (random and sine) prior to their empirical application, describing the dyadic behavior of athletes in team games. The authors consider one of the ApEn normalized measures to generate the 95th percentile envelopes that can be used to test whether a particular social neurobiological system is highly complex (i.e., generates highly unpredictable time series). Results demonstrated that suggested measures may be considered as valid instruments for measuring and comparing complexity in systems that produce time series with inconsistent lengths.