While there is a growing body of research on second language acquisition (SLA) in children, adolescents, young and more mature adults, much remains to be explored about how adults in later life learn a new language and how good additional language learning is for them. Our goal in this article is to survey and evaluate what is known about the linguistic, socio-affective, neurobiological and cognitive underpinnings of the second language (L2) learning process in older individuals, the extent to which L2 acquisition may be seen as contributing to healthy and active ageing, and how these phenomena are to be approached scientifically, methodologically and pedagogically. Our view is that a developmental enterprise as complex as L2 learning in senior adulthood and its effects in later life cannot be explained by a single theory or set of principles. Furthermore, we take it that L2 acquisition in the third age needs to be regarded not just as a goal in itself but as a means of promoting social interaction and integration, and that it is partly through the stimulation of social well-being that its cognitive effects may potentially be observed.

This article is concerned with age in second language learning. It steers well clear, however, of the well-worn issue of maturational constraints and the intractable problems of locating their consensual offset point and finding indisputable evidence for or against them. Instead we propose something completely different in our agenda for age-related research: a programme on some poorly understood non-maturational dimensions of the age factor which will stand some chance of yielding results unlikely to become entangled in theoretical controversy. In other words, the results will, we think, be immediately usable and useful. The topics included in our outlined agenda are: (1) age effects in various dimensions of language teaching and learning (in relation to bilingualism and biliteracy, to different target languages and to Content and Language Integrated Learning (CLIL); (2) what can be observed in respect of second language (L2) learning in the third age; (3) an ecological perspective on age in classroom L2 research methodology; and (4) an exploration of the attitudes of teachers of different-aged L2 learners.

The present study aimed to identify predictors of one aspect of sign language acquisition, sign learning, in hearing nonsigners. Candidate predictors were selected based on the theory that the observed relationship between phonological short-term memory and L2 lexical learning is due in part to common perceptual-motor processes. Hearing nonsigning adults completed a sign learning task, three assessments of short-term memory for movements (movement STM; two of which used sign-like stimuli), and two visuospatial STM tasks. The final sample included 103 adults, ranging between 18 and 33 years of age. All predictors were moderately to strongly correlated with the sign learning task and to each other. A series of regression analyses revealed that both movement and visuospatial STM uniquely contributed to the prediction of sign learning. These results suggest that perceptual-motor processes play a significant role in sign learning and raise questions about the role of phonological processing.

This article addresses age-related attainment effects in second language acquisition, posing the question of whether such effects are to be explained in terms of a Critical Period with a predictable and abrupt offset point or in terms of the impact of a wider range of factors. It attempts to explore this question by focusing on four discussion points in the current debate: (i) the wide use of native-speaker behaviour as the key L2 attainment yardstick; (ii) the degree of compatibility of prevailing views regarding the notion of a critical period for L2 acquisition; (iii) the relative narrowness of much research in this area, where age of L2 onset is often regarded as the crucial if not the only critical variable; and (iv) insights relative to maturational constraints on language acquisition offered by recent brain research. The article concludes that a loosening of the association between ultimate L2 attainment research and Critical Period Hypothesis (CPH) issues would shed more light on L2 attainment in terms both of the comprehensiveness and of the acuity of the insights which would result.

The existence and selection of steady-state travelling planar fronts in a set of typical phase field equations for solidification are investigated by a combination of numerical and analytical methods. Such solutions are conjectured to exist only for a unique velocity of propagation and to be unique except for translation. This behaviour is in marked contrast to the situation in conventional Stefan models in which travelling fronts exist for all velocities. The value of the steady-state velocity depends upon the various material parameters which enter the phase field equations. Numerical and, in certain tractable limits, analytical results for the velocity are presented for a number of physical situations.

The idea that there is an age factor in language development has long been — and continues to be — a hotly debated topic. This review begins by briefly revisiting some of the early perspectives on this issue; it goes on to sketch some of the relevant findings which emerged in the three decades following the onset in the late 1960s of serious empirical investigation of the age factor in L2 acquisition; and, finally, in the third section of the survey, it hones in on the results of some more recently published age-related research. The article concludes with a short discussion — in the light of the foregoing — of (a) the degree of absoluteness of the age factor in L2 acquisition; and (b) the notion that there may be not one, but a number, of age-related factors at work.