L1 transfer in the acquisition of manner and path in Spanish by native speakers of English

In this article the authors argue that L1 transfer from English is not only important in the early stages of L2 acquisition of Spanish, but remains influential in later stages if there is not enough positive evidence for the learners to progress in their development (Lefebvre, White, & Jourdan, 2006). The findings are based on analyses of path and manner of movement in stories told by British students of Spanish (N = 68) of three different proficiency levels. Verbs that conflate motion and path, on the one hand, are mastered early, possibly because the existence of Latinate path verbs, such as enter and ascend in English, facilitate their early acquisition by British learners of Spanish. Contrary to the findings of Cadierno (2004) and Cadierno and Ruiz (2006), the encoding of manner, in particular in boundary crossing contexts, seems to pose enormous difficulties, even among students who had been abroad on a placement in a Spanish-speaking country prior to the data collection. An analysis of the frequency of manner verbs in Spanish corpora shows that one of the key reasons why students struggle with manner is that manner verbs are so infrequent in Spanish. The authors claim that scarce positive evidence in the language exposed to and little or no negative evidence are responsible for the long-lasting effect of transfer on the expression of manner.

The Acquisition of Aspect in L2 Portuguese & Spanish: Exploring Native/Non-Native Performance Differences.

This study investigates the possibility of native-like ultimate attainment by analyzing L2 knowledge of aspect as seen in the Preterit/Imperfect contrast of highly successful English L2 learners of Portuguese and Spanish. Building on innovative work by Montrul & Slabakova (2003) and Slabakova & Montrul (2003), we test knowledge of semantic entailments associated with the acquisition of [+/- perfective] features checked in higher AspP. Additionally, we investigate the possibility of a specific pattern of associated target-deviant L2 performance. We hypothesize that L2 performance can be affected by explicit positive evidence (pedagogical rules) despite otherwise demonstrable native-like competence. Indeed, the data reveal a pattern of target-deviant performance noted only in three specific contexts, all of which can be linked to traditional instruction: (a) with particular stative verbs not used in the Preterit (b) when preceded by certain adverbial phrases (e.g.,siempre) and (c) so-called semantic shifting verbs (e.g., sabía vs. supe).

Inhibitory control in memory: evidence for negative priming in free recall

Cognitive control mechanisms—such as inhibition—decrease the likelihood that goal-directed activity is ceded to irrelevant events. Here, we use the action of auditory distraction to show how retrieval from episodic long-term memory is affected by competitor inhibition. Typically, a sequence of to-be-ignored spoken distracters drawn from the same semantic category as a list of visually-presented to-be-recalled items impairs free recall performance. In line with competitor inhibition theory (Anderson, 2003), free recall was worse for items on a probe trial if they were a repeat of distracter items presented during the previous, prime, trial (Experiment 1). This effect was only produced when the distracters were dominant members of the same category as the to-be-recalled items on the prime. For prime trials in which distracters were low-dominant members of the to-be-remembered item category or were unrelated to that category—and hence not strong competitors for retrieval—positive priming was found (Experiments 2 & 3). These results are discussed in terms of inhibitory approaches to negative priming and memory retrieval.

Evidence for interplay between genes and maternal stress in utero: monoamine oxidase A polymorphism moderates effects of life events during pregnancy on infant negative emotionality at 5 weeks

The low activity variant of the monoamine oxidase A (MAOA) functional promoter polymorphism, MAOA-LPR, in interaction with adverse environments (G × E) is associated with child and adult antisocial behaviour disorders. MAOA is expressed during foetal development so in utero G × E may influence early neurodevelopment. We tested the hypothesis that MAOA G × E during pregnancy predicts infant negative emotionality soon after birth. In an epidemiological longitudinal study starting in pregnancy, using a two stage stratified design, we ascertained MAOA-LPR status (low vs. high activity variants) from the saliva of 209 infants (104 boys and 105 girls), and examined predictions to observed infant negative emotionality at 5 weeks post-partum from life events during pregnancy. In analyses weighted to provide estimates for the general population, and including possible confounders for life events, there was an MAOA status by life events interaction (P = 0.017). There was also an interaction between MAOA status and neighbourhood deprivation (P = 0.028). Both interactions arose from a greater effect of increasing life events on negative emotionality in the MAOA-LPR low activity, compared with MAOA-LPR high activity infants. The study provides the first evidence of moderation by MAOA-LPR of the effect of the social environment in pregnancy on negative emotionality in infancy, an early risk for the development of child and adult antisocial behaviour disorders.

Observational evidence for a negative shortwave cloud feedback in middle to high latitudes

Exploiting the observed robust relationships between temperature and optical depth in extratropical clouds, we calculate the shortwave cloud feedback from historical data, by regressing observed and modeled cloud property histograms onto local temperature in middle to high southern latitudes. In this region, all CMIP5 models and observational data sets predict a negative cloud feedback, mainly driven by optical thickening. Between 45° and 60°S, the mean observed shortwave feedback (−0.91 ± 0.82 W m−2 K−1, relative to local rather than global mean warming) is very close to the multimodel mean feedback in RCP8.5 (−0.98 W m−2 K−1), despite differences in the meridional structure. In models, historical temperature-cloud property relationships reliably predict the forced RCP8.5 response. Because simple theory predicts this optical thickening with warming, and cloud amount changes are relatively small, we conclude that the shortwave cloud feedback is very likely negative in the real world at middle to high latitudes.

The influence of affective statements on performance on implicit and explicit memory tasks

Consumers are often exposed to brand names presented concurrently with information such as brand claims and warnings, prior to making product choices. As implicit memory has been implicated in the consumer choice process, two experiments were conducted to assess the influence of additional information, namely simple positive and negative statements, on implicit and explicit memory tasks. In Experiment 1, the mere presence of additional statements at study significantly reduced performance on a two-alternatives forced recognition task. However, the same manipulation had no effect on implicit preference judgement task performance. The valence of the accompanying information had no effect on either task. In Experiment 2, using modified implicit and explicit choice tasks, performance on the former was unaffected by statement valence, whereas the latter task was. Hence, positive priming was obtained for brand names previously shown with negative information. The results of the experiments are discussed in relation to both implicit memory and consumer choice.

Negative correlations between control performance and verbalizable knowledge: indicators for implicit learning in process control tasks?

Negative correlations between task performance in dynamic control tasks and verbalizable knowledge, as assessed by a post-task questionnaire, have been interpreted as dissociations that indicate two antagonistic modes of learning, one being “explicit”, the other “implicit”. This paper views the control tasks as finite-state automata and offers an alternative interpretation of these negative correlations. It is argued that “good controllers” observe fewer different state transitions and, consequently, can answer fewer post-task questions about system transitions than can “bad controllers”. Two experiments demonstrate the validity of the argument by showing the predicted negative relationship between control performance and the number of explored state transitions, and the predicted positive relationship between the number of explored state transitions and questionnaire scores. However, the experiments also elucidate important boundary conditions for the critical effects. We discuss the implications of these findings, and of other problems arising from the process control paradigm, for conclusions about implicit versus explicit learning processes.

Ecological specificity of arbuscular mycorrhizae: evidence from foliar- and seed-feeding insects

Arbuscular mycorrhizal (AM) fungi have a variety of effects on foliar-feeding insects, with the majority of these being positive, although reports of negative and null effects also exist. Virtually all previous experiments have used mobile insects confined in cages and have studied the effects of one, or at most two, species of mycorrhizae on one species of insect. The purpose of this study was to introduce a greater level of realism into insect-mycorrhizal experiments, by studying the responses of different insect feeding guilds to a variety of AM fungi. We conducted two experiments involving three species of relatively immobile insects (a leaf-mining and two seed-feeding flies) reared in natural conditions on a host (Leucanthemum vulgare). In a field study, natural levels of AM colonization were reduced, while in a phytometer trial, we experimentally colonized host plants with all possible combinations of three known mycorrhizal associates of L. vulgare. In general, AM fungi increased the stature (height and leaf number) and nitrogen content of plants. However, these effects changed through the season and were,dependent on the identity of the fungi in the root system. AM fungi increased host acceptance of all three insects and larval performance of the leaf miner, but these effects were also season- and AM species-dependent. We suggest that the mycorrhizal effect on the performance of the leaf miner is due to fungal-induced changes in host-plant nitrogen content, detected by the adult fly. However, variability in the effect was apparent, because not all AM species increased plant N content. Meanwhile, positive effects of mycorrhizae were found on flower number and flower size, and these appeared to result in enhanced infestation levels by the seed-feeding insects. The results show that AM fungi exhibit ecological specificity, in that different. species have different effects on host-plant growth and chemistry and the performance of foliar-feeding insects. Future studies need to conduct experiments that use ecologically realistic combinations of plants and fungi and allow insects to be reared in natural conditions.

Genetic evidence of frequent long-distance recruitment in a vertebrate-dispersed tree

The importance of dispersal for the maintenance of biodiversity, while long-recognized, has remained unresolved. We used molecular markers to measure effective dispersal in a natural population of the vertebrate-dispersed Neotropical tree, Simarouba amara (Simaroubaceae) by comparing the distances between maternal parents and their offspring and comparing gene movement via seed and pollen in the 50 ha plot of the Barro Colorado Island forest, Central Panama. In all cases (parent-pair, mother-offspring, father-offspring, sib-sib) distances between related pairs were significantly greater than distances to nearest possible neighbours within each category. Long-distance seedling establishment was frequent: 74% of assigned seedlings established > 100 m from the maternal parent [mean = 392 +/- 234.6 m (SD), range = 9.3-1000.5 m] and pollen-mediated gene flow was comparable to that of seed [mean = 345.0 +/- 157.7 m (SD), range 57.6-739.7 m]. For S. amara we found approximately a 10-fold difference between distances estimated by inverse modelling and mean seedling recruitment distances (39 m vs. 392 m). Our findings have important implications for future studies in forest demography and regeneration, with most seedlings establishing at distances far exceeding those demonstrated by negative density-dependent effects.

Atopococcus tabaci gen. nov., sp nov., a novel Gram-positive, catalase-negative, coccus-shaped bacterium isolated from tobacco

A novel Gram-positive, aerobic, catalase-negative, coccus-shaped organism originating from tobacco was characterized using phenotypic and molecular taxonomic methods. The organism contained a cell wall murein based on L-lysine (variation A4 alpha, type L-lysine-L-glutamic acid), synthesized long-chain cellular fatty acids of the straight-chain saturated and monounsaturated types (with C(16:1)omega 9, C-16:0 and C(18:1)omega 9 predominating) and possessed a DNA G+C content of 46 mol%. Based on morphological, biochemical and chemical characteristics, the coccus-shaped organism did not conform to any presently recognized taxon. Comparative 16S rRNA gene sequencing studies confirmed the distinctiveness of the unknown coccus, with the bacterium displaying sequence divergence values of greater than 7% with other recognized Gram-positive taxa. Treeing analysis reinforced its distinctiveness, with the unidentified organism forming a relatively long subline branching at the periphery of an rRNA gene sequence cluster which encompasses the genera Alloiococcus, Allolustis, Alkalibacterium, Atopostipes, Dolosigranulum and Marinilactibacillus. Based on phenotypic and molecular phylogenetic evidence, it is proposed that the unknown organism from tobacco be classified as a new genus and species, Atopococcus tabaci gen. nov., sp. nov. The type strain of Atopococcus tabaci is CCUG 48253(T) (= CIP 108502(T)).

The psychological, neurochemical and functional neuroanatomical mediators of the effects of positive and negative mood on executive functions

In this review we evaluate the cognitive and neural effects of positive and negative mood on executive function. Mild manipulations of negative mood appear to have little effect on cognitive control processes, whereas positive mood impairs aspects of updating, planning and switching. These cognitive effects may be linked to neurochemistry: with positive mood effects mediated by dopamine while negative mood effects may be mediated by serotonin levels. Current evidence on the effects of mood on regional brain activity during executive functions, indicates that the prefrontal cortex is a recurrent site of integration between mood and cognition. We conclude that there is a disparity between the importance of this topic and awareness of how mood affects, executive functions in the brain. Most behavioural and neuroimaging studies of executive function in normal samples do not explore the potential role of variations in mood, yet the evidence we outline indicates that even mild fluctuations in mood can have a significant influence on neural activation and cognition. (c) 2006 Elsevier Ltd. All rights reserved.

Anterior cingulate activity and level of cognitive conflict: explicit comparisons

The role of anterior cingulate cortex (ACC) in attention is a matter of debate. One hypothesis suggests that its role is to monitor response-level conflict, but explicit evidence is somewhat lacking. In this study, the activation of ACC was compared in (a) color and number standard Stroop tasks in which response preparation and interference shared modality (response-level conflict) and (b) color and number matching Stroop tasks in which response preparation and interference did not share modality (non-response-level conflict). In the congruent conditions, there was no effect of task type. In the interference conditions, anterior cingulate activity in the matching tasks was less than that in the standard tasks. These results support the hypothesis that ACC specifically mediates generalized modality-independent selection processes invoked by response competition.

Depression, confidence, and decision: evidence against depressive realism

This research examined how retrospective self-assessments of performance are affected by major depression. To test the validity of the depressive realism versus the selective processing hypotheses, aggregate posttest performance estimates (PTPEs) were obtained from clinically depressed patients and an age-matched comparison group across 4 decision tasks (object recognition, general knowledge, social judgment, and line-length judgment). As expected on the basis of previous findings, both groups were underconfident in their PTPEs, consistently underestimating the percentage of questions they had answered correctly. Contrary to depressive realism, and in partial support of the selective processing account, this underconfidence effect was not reduced but modestly exacerbated in the depressed patients. Further, whereas the PTPEs of the comparison group exceeded that expected on the basis of chance alone those of the depressed individuals did not. The results provide no support for the depressive realism account and suggest that negative biases contribute to metacognitive information processing in major depression.

Adaptive control of event integration: evidence from event-related potentials

We investigated whether it is possible to control the temporal window of attention used to rapidly integrate visual information. To study the underlying neural mechanisms, we recorded ERPs in an attentional blink task, known to elicit Lag-1 sparing. Lag-1 sparing fosters joint integration of the two targets, evidenced by increased order errors. Short versus long integration windows were induced by showing participants mostly fast or slow stimuli. Participants expecting slow speed used a longer integration window, increasing joint integration. Difference waves showed an early (200 ms post-T2) negative and a late positive modulation (390 ms) in the fast group, but not in the slow group. The modulations suggest the creation of a separate event for T2, which is not needed in the slow group, where targets were often jointly integrated. This suggests that attention can be guided by global expectations of presentation speed within tens of milliseconds.

Temperature and the development rates of thrips: evidence for a constraint on local adaptation?

Typically, the relationship between insect development and temperature is described by two characteristics: the minimum temperature needed for development to occur (T-min) and the number of day degrees required (DDR) for the completion of development. We investigated these characteristics in three English populations of Thrips major and T tabaci [Cawood, Yorkshire (N53degrees49', W1degrees7'); Boxworth, Cambridgeshire (N52degrees15', W0degrees1'); Silwood Park, Berkshire (N51degrees24', W0degrees38')], and two populations of Frankliniella occidentalis (Cawood; Silwood Park). While there were no significant differences among populations in either T-min (mean for T major = 7.0degreesC; T tabaci = 5.9degreesC; F. occidentalis = 6.7degreesC) or DDR (mean for T major = 229.9; T tabaci = 260.8; F occidentalis = 233.4), there were significant differences in the relationship between temperature and body size, suggesting the presence of geographic variation in this trait. Using published data, in addition to those newly collected, we found a negative relationship between T-min. and DDR for F occidentalis and T tabaci, supporting the hypothesis that a trade-off between T-min and DDR may constrain adaptation to local climatic conditions.