Age of acquisition effects in vocabulary learning

Two experiments examined whether the age of acquisition (AoA) of a concept influences the speed at which native English speakers are able to name pictures using a newly acquired second language (L2) vocabulary. In Experiment 1, participants were taught L2 words associated with pictures. In Experiment 2 a second group of participants were taught the same words associated with L1 translations. Following training both groups performed a picture naming task in which they were asked to name pictures using the newly acquired words. Significant AoA effects were observed only in Experiment 1, in that participants were faster at naming pictures representing early acquired relative to late acquired concepts. The results suggest that the AoA of a concept can exert influence over processing which is independent of the AoA of the word form. The results also indicate that different training methods may lead to qualitative differences in the nature of the links formed between words and concepts during the earliest stages of second language learning.     

Response acquisition and fixed-ratio escalation based on interresponse times in rats

The effectiveness of a fixed‐ratio (FR) escalation procedure, developed by Pinkston and Branch (2004) and based on interresponse times (IRTs), was assessed during lever‐press acquisition. Forty‐nine experimentally naïve adult male Long Evans rats were deprived of food for 24 hr prior to an extended acquisition session. Before the start of the session, three food pellets were placed in the magazine. Otherwise, no magazine training, shaping, nor autoshaping procedure was employed. The first 20 presses each resulted in the delivery of a 45‐mg food pellet. Then, the FR increased (2, 4, 8, 11, 16, 20, 25, 30) when each IRT in the ratio was less than 2 s during three consecutive ratios. Sessions lasted 13 hr or until 500 pellets were earned. On average, rats reached a terminal ratio of 11 (mean) or 16 (median) during the first session. Seven rats reached the maximum value of FR 30 and only one rat did not acquire the response. In most rats, a break‐and‐run pattern of responding characteristic of FR schedules began to develop in this acquisition session. Subsequently, the ratio‐escalation procedure continued during daily 2‐hr sessions. In these sessions, the starting ratio requirement was set at the terminal ratio reached in the previous session. Using this procedure, over half (26) of the rats reached the FR 30 requirement by the fourth session. These data demonstrate that a ratio‐escalation procedure based on IRTs provides a time‐efficient way of establishing ratio responding.     

Learning new vocabulary during childhood: Effects of semantic training on lexical consolidation and integration

Research suggests that word learning is an extended process, with offline consolidation crucial for the strengthening of new lexical representations and their integration with existing lexical knowledge (as measured by engagement in lexical competition). This supports a dual memory systems account, in which new information is initially sparsely encoded separately from existing knowledge and integrated with long-term memory over time. However, previous studies of this type exploited unnatural learning contexts, involving fictitious words in the absence of word meaning. In this study, 5- to 9-year-old children learned real science words (e.g., hippocampus) with or without semantic information. Children in both groups were slower to detect pauses in familiar competitor words (e.g., hippopotamus) relative to control words 24 h after training but not immediately, confirming that offline consolidation is required before new words are integrated with the lexicon and engage in lexical competition. Children recalled more new words 24 h after training than immediately (with similar improvements shown for the recall and recognition of new word meanings); however, children who were exposed to the meanings during training showed further improvements in recall after 1 week and outperformed children who were not exposed to meanings. These findings support the dual memory systems account of vocabulary acquisition and suggest that the association of a new phonological form with semantic information is critical for the development of stable lexical representations.     

Form and Variability During Sit-to-Stand Transitions: Children Versus Adults

In performing the sit-to-stand transition, young children (6- to 7-year-olds) were expected to display a movement form similar to that of adults. However, movement consistency was predicted to be poorer in children than in adults because they lack refinement of motor control processes. Kinematic analysis of 10 repetitions of the sit-to-stand movement was carried out for 6 typically developing children and 6 adults. Supporting the authors' prediction of comparable form, no differences were evident between age groups for sequence of joint onsets, proportional duration of segmental motion, or in angle-angle plots of displacement at 2 segments. In contrast, within-participant variability was found to be higher for children: Coefficients of variation for most kinematic measures were twice those seen for adults. The authors interpret the children's lack of movement consistency as a reflection of inadequate stabilization of an internal model of intersegmental dynamics. Whereas adults have attained a skill level associated with refinement of that model, children have not. Children have an additional control problem because changes in body morphology throughout childhood require ongoing updating of the internal model that controls intrinsic dynamics.     

Acquisition of Predictable Vertical Visual Targets: Eye-Head Coordination and the Triggering Effect

The study was designed to investigate target acquisition in the vertical plane with emphasis on establishing strategy differences associated with acquisition triggering methods. Eight subjects were tested. Measurements consisted of target acquisition time, eye-head latency differences, velocity of gaze, eyes and head, and head amplitude. Using 3-way repeated measures analyses of variance the results show that the strategy for acquisition of predictable visual targets in vertical plane with the head unrestrained significantly depended on (a) the direction of the gaze motion with respect to the gravity vector (i.e., there is significant up-down asymmetry), (b) the angular distance of the target, and (c) the method of triggering the command to acquire the target—external versus internal. The data also show that when vertical acquisition is compared with triggering methods in the horizontal plane there is a difference in overall strategy for the acquisition of targets with the same spatial distances from straight ahead gaze when both the eyes and head are used. Among the factors contributing to the difference in strategy for vertical target acquisition are the gravitational vector, the relationship of target displacement and vestibular activitation, biomechanical and neural control asymmetries, and the difference in the vertical field of view.     

Developing Roles and Skills in Community-Living Adults With Severe and Persistent Mental Illness

People with severe and persistent mental illness often experience a disruption in the development of social roles, and the skills within these roles. Role Development, a set of guidelines for practice, is an intervention to develop roles and skills. The purpose of this study was to continue to examine the efficacy of this intervention. Ten people attending two community mental health programs participated in evaluation and treatment based on Role Development. Quantitative pretest and posttest measures were used. Qualitative components were incorporated to get a sense of the experience involved in developing roles and skills. Quantitative results indicated statistical significance (p < .05) in the development of roles and skills. Qualitative data revealed multiple trends experienced by the participants. This study contributes to the evidenced-based knowledge regarding development of roles and skills for persons living with severe and persistent mental illness.     

Language aptitude for pronunciation in advanced second language (L2) Learners: Behavioural predictors and neural substrates

Individual differences in second language (L2) aptitude have been assumed to depend upon a variety of cognitive and personality factors. Especially, the cognitive factor phonological working memory has been conceptualised as language learning device. However, strong associations between phonological working memory and L2 aptitude have been previously found in early-stage learners only, not in advanced learners. The current study aimed at investigating the behavioural and neurobiological predictors of advanced L2 learning. Our behavioural results showed that phonetic coding ability and empathy, but not phonological working memory, predict L2 pronunciation aptitude in advanced learners. Second, functional neuroimaging revealed this behavioural trait to be correlated with hemodynamic responses of the cerebral network of speech motor control and auditory-perceptual areas. We suggest that the acquisition of L2 pronunciation aptitude is a dynamic process, requiring a variety of neural resources at different processing stages over time.     

How Do Children Restrict Their Linguistic Generalizations? An (Un‐)Grammaticality Judgment Study

A paradox at the heart of language acquisition research is that, to achieve adult‐like competence, children must acquire the ability to generalize verbs into non‐attested structures, while avoiding utterances that are deemed ungrammatical by native speakers. For example, children must learn that, to denote the reversal of an action, un‐ can be added to many verbs, but not all (e.g., roll/unroll; close/*unclose). This study compared theoretical accounts of how this is done. Children aged 5–6 (N = 18), 9–10 (N = 18), and adults (N = 18) rated the acceptability of un‐ prefixed forms of 48 verbs (and, as a control, bare forms). Across verbs, a negative correlation was observed between the acceptability of ungrammatical un‐ prefixed forms (e.g., *unclose) and the frequency of (a) the bare form and (b) alternative forms (e.g., open), supporting the entrenchment and pre‐emption hypotheses, respectively. Independent ratings of the extent to which verbs instantiate the semantic properties characteristic of a hypothesized semantic cryptotype for un‐ prefixation were a significant positive predictor of acceptability, for all age groups. The relative importance of each factor differed for attested and unattested un‐ forms and also varied with age. The findings are interpreted in the context of a new hybrid account designed to incorporate the three factors of entrenchment, pre‐emption, and verb semantics.     

Integration and Reuse in Cognitive Skill Acquisition

Previous accounts of cognitive skill acquisition have demonstrated how procedural knowledge can be obtained and transformed over time into skilled task performance. This article focuses on a complementary aspect of skill acquisition, namely the integration and reuse of previously known component skills. The article posits that, in addition to mechanisms that proceduralize knowledge into more efficient forms, skill acquisition requires tight integration of newly acquired knowledge and previously learned knowledge. Skill acquisition also benefits from reuse of existing knowledge across disparate task domains, relying on indexicals to reference and share necessary information across knowledge components. To demonstrate these ideas, the article proposes a computational model of skill acquisition from instructions focused on integration and reuse, and applies this model to account for behavior across seven task domains.