Eye-movements in implicit artificial grammar learning

Artificial grammar learning (AGL) has been probed with forced-choice behavioral tests (active tests). Recent attempts to probe the outcomes of learning (implicitly acquired knowledge) with eye-movement responses (passive tests) have shown null results. However, these latter studies have not tested for sensitivity effects, for example, increased eye movements on a printed violation. In this study, we tested for sensitivity effects in AGL tests with (Experiment 1) and without (Experiment 2) concurrent active tests (preference- and grammaticality classification) in an eye-tracking experiment. Eye movements discriminated between sequence types in passive tests and more so in active tests. The eye-movement profile did not differ between preference and grammaticality classification, and it resembled sensitivity effects commonly observed in natural syntax processing. Our findings show that the outcomes of implicit structured sequence learning can be characterized in eye tracking. More specifically, whole trial measures (dwell time, number of fixations) showed robust AGL effects, whereas first-pass measures (first-fixation duration) did not. Furthermore, our findings strengthen the link between artificial and natural syntax processing, and they shed light on the factors that determine performance differences in preference and grammaticality classification tests.Max Planck Institute for PsycholinguisticsDonders Institute for Brain, Cognition and BehaviorVetenskapsradetSwedish Dyslexia Foundatio

Implicit learning mechanisms and their application to dyslexia

mechanisms and their association with reading and writing processes, both in typical readers and in readers with dyslexia. In the first study, we explored whether the outcomes of implicit structural sequence learning could be captured in eye movement responses. We tested for sensitivity effects (increased eye movements on a printed violation in an implicit artificial grammar learning task) in two experiments that manipulated the presence of a concurrent behavioural classification test. Results show different eye movement patterns when participants discriminate grammatical and non-grammatical sequences in passive viewing of sequences and that this effect is boosted when participants perform a concomitant classification task. This study shows that implicit acquired knowledge can be detected through the analysis of eye-movement patterns, enabling the study of implicit learning without explicit processing interference. In study two, we investigated the influence of implicit learning in the literacy skills of adult typical readers. Three main results prompt us to conclude that implicit learning contributes to reading and writing proficiency: 1) in implicit orthographic knowledge tasks where the frequency of orthographic patterns is manipulated, participants tend to choose the most frequent pattern; 2) reading proficiency and the implicit orthographic knowledge decision task were related to an implicit learning task; and 3) implicit learning increases the impact of exposure to print on reading fluency. Altogether, these results suggest a role of implicit learning capacity in the extraction the written language regularities and in the improvement of literacy skills. In study three, we tested whether dyslexic children present an implicit learning deficit that could contribute to their reading disability. An implicit artificial grammar learning task designed to optimize exposure to regularities was presented to dyslexic children and to two control groups matched by age and reading level. Results showed that dyslexics’ implicit learning abilities are at same level as both control groups, suggesting that the characteristic reading difficulties presented by dyslexics cannot be explained by implicit learning deficits. In conclusion, the studies presented in this thesis provide evidence that: 1) implicit learning can be tested with minimal interference of explicit processes by measuring eye movement sensitivity patterns; 2) implicit learning intervenes in the extraction of written regularities, contributing to literacy proficiency; and 3) dyslexic children do not present an implicit learning deficit and thus can benefit from this preserved ability to improve their reading skills

Implicit learning in dyslexic children

Dissertação de mest., Neurociências Cognitivas e Neuropsicologia (Neuropsicologia), Faculdade de Ciências Humanas e Sociais, Univ. do Algarve, 2011A dislexia é uma perturbação específica de aprendizagem de origem neurobiológica, caracterizada por dificuldades no reconhecimento exacto e/ou fluente de palavras escritas e por dificuldades ortográficas e de descodificação. Estas dificuldades coexistem com capacidades cognitivas normais e surgem apesar de existir instrução e condições sócio-económicas adequadas. Ao longo das últimas décadas tem-se observado uma explosão de estudos dedicados a identificar quais os défices manifestados pelos disléxicos e qual a sua causa. Mais recentemente, alguma desta investigação tem-se centrado nas capacidades de aprendizagem implícita e eventuais défices nestas capacidades apresentados pelos disléxicos. A aprendizagem implícita é definida pela aprendizagem não intencional de informação complexa, desenvolvida de um modo automático apenas pela constante exposição às regularidades ambientais. Esta aprendizagem ocorre sem que a pessoa tenha intenção de o fazer e sem conhecimento explícito e verbalizável do conteúdo aprendido. Na aprendizagem da leitura e escrita as crianças estão expostas não só a processos explícitos, mas também a processos implícitos. Inicialmente, as crianças adquirem explicitamente as correspondências grafema-fonema e posteriormente estas correspondências passam a ser aplicadas, e até adquiridas, de um modo implícito (Gombert, 2003; Sperling, Lu, & Manis, 2004). Simultaneamente, as regularidades dos sistemas de escrita podem também ser extraídas implicitamente, sob a forma de padrões visuais (ortografia), palavras ditas oralmente e associadas a esses padrões (fonologia e léxico) ou pelo significado que estes padrões activam (morfologia e léxico) (Gombert, 2003). Processos implícitos estarão também presentes quando a aquisição de significado associado a este padrão ortográfico é efectuado através do contexto (Howard, Howard, Japikse, & Eden, 2006). Esta combinação de processos explícitos e implícitos na aquisição da leitura leva-nos a pressupor que um défice nas capacidades de aprendizagem implícita pode contribuir para as dificuldades apresentadas pelas crianças disléxicas. Contudo, os poucos estudos sobre a aprendizagem implícita em disléxicos têm revelado resultados díspares. Enquanto alguns autores referem que os disléxicos apresentam um défice na aprendizagem implícita (Pavlidou & Williams, 2010; Pavlidou, Williams, & Kelly, 2009; Sperling et al., 2004; Stoodley, Harrison, & Stein, 2006; Vicari, Marotta, Menghini, Molinari, & Petrosini, 2003), outros estudosapontam para que estas capacidades estejam intactas em crianças e adultos disléxicos (Kelly, Griffiths, & Frith, 2002; Roodenrys & Dunn, 2008; Russeler, Gerth, & Munte, 2006; Waber et al., 2003). Alguns autores referem que esta discrepância de resultados se deve à utilização de diferentes provas, que podem estar a avaliar diferentes processos de aprendizagem implícita e que os disléxicos podem ter défices apenas em alguns destes processos (Howard et al., 2006). Com o presente estudo pretendemos clarificar esta questão, investigando se crianças disléxicas apresentam capacidades de aprendizagem implícita. Para tal, foi utilizado um paradigma de aprendizagem implícita complexo, a aprendizagem de gramática artificial, mas adaptado a crianças disléxicas. Adicionalmente, examinámos a relação entre a aprendizagem implícita e as competências de leitura e outras capacidades relacionadas com a leitura. Participaram no estudo doze crianças com diagnóstico ou suspeita de dislexia, do 2º ao 4º ano de escolaridade. Este grupo foi emparelhado com dois grupos de controlo: um grupo equivalente em termos de idade e escolaridade e outro grupo equiparado em termos de capacidade de leitura, todos do 1º ano de escolaridade. Todos os grupos realizaram provas complementares de leitura, escrita, consciência fonológica, nomeação rápida, vocabulário e memória de trabalho. A experiência de aprendizagem de gramática artificial foi dividida em três sessões, realizadas em três dias seguidos. No início de cada sessão os participantes realizavam uma prova de memória (as crianças memorizavam sequências de símbolos coloridos e posteriormente tinham de reproduzir a sequência memorizada, com recurso a uma caixa de resposta apropriada), na qual eram expostos a sequências gramaticais, sem terem conhecimento desse facto. Na última sessão os participantes foram informados de que as sequências que tinham visto na prova de memória obedeciam a conjunto de regras complexo e foi-lhes pedido que classificassem um novo conjunto de sequências, constituído por sequencias gramaticais e não gramaticais. No fim de cada sessão, os participantes eram entrevistados no sentido de se verificar se estes possuiam conhecimento explícito acerca das regras subjacentes às sequências gramaticais. Os resultados revelaram que não havia diferenças significativas no desempenho dos disléxicos e dos dois grupos de controlo na prova de classificação de sequências. Este resultado indica que todas as crianças deste estudo extraíram as regularidades dos estímulos ao mesmo nível. Foi ainda calculado um índice de discriminação (d’) que também não diferiu entre os grupos. Apesar de não haver diferenças entre grupos, o desempenho geral dos participantes foi mais baixo do que o esperado. Procedeu-se então a uma análise individual do desempenho dos sujeitos e verificou-se que alguns disléxicos apresentavam índices de discriminação bastante elevados. O mesmo padrão foi observado nos grupos de controlo. Através das entrevistas pós-experimentais verificámos também que os sujeitos não tinham conhecimento explícito acerca das regras subjacentes às sequencias gramaticais. Todos estes dados levam-nos a concluir que os disléxicos são capazes de extrair as regularidades implícitas de uma gramática artificial ao mesmo nível que as crianças sem défices de leitura. Os nossos dados levam-nos a supor que os diferentes resultados observados nos estudos de aprendizagem implícita em disléxicos pode dever-se não só à grande variação das provas utilizadas para avaliar a aprendizagem implícita (diferentes paradigmas, com diferentes estímlos, diferentes comprimentos de sequências, diferentes tipos de resposta e consequentemente com procedimentos experimental diferente), mas também devido às características da amostra. Os critérios de inclusão dos disléxicos nos estudos também diferem de um estudo para outro e muitas vezes não há qualquer reavaliação das capacidades dos disléxicos. Simultaneamente as diferenças individuais dentro do grupo dos disléxicos são também habitualmente ignoradas. Estas diferenças individuais podem estar na origem desta discrepância de desempenho apresentado pelos disléxicos nos diferentes estudos. Estudos futuros, com maiores amostras de disléxicos e com uma avaliação mais detalhada das suas características individuais podem clarificar esta questão. Em suma, o nosso estudo revela que a capacidade de aprendizagem implícita de gramática artificial está presente em crianças disléxicas. O ensino da leitura e os programas de intervenção na dislexia podem explorar estas capacidades de aprendizagem implícita preservadas nos disléxicos para auxiliar os processos explícitos na aquisição das competências de leitura

A influência das competências de leitura nas estratégias de dupla codificação

Recentemente, alguns autores demonstraram que o desempenho em provas de memória não verbal pode envolver o recurso simultâneo a estratégias verbais e visuo-espaciais para codificar a informação. A leitura tem sido apontada como um factor que pode contribuir para o desenvolvimento destas estratégias de dupla codificação. Neste estudo, fomos investigar se a capacidade de leitura interfere de algum modo na utilização de mecanismos de dupla codificação. Comparámos o desempenho de dois grupos de crianças com diferentes competências de leitura, mas equivalentes na idade e em anos de escolaridade, numa prova de memória não verbal. Foram definidas três condições experimentais, manipulando o grau em que os itens a memorizar eram verbalizáveis. Os resultados mostraram que o grupo com melhores competências de leitura apresenta um desempenho superior na condição pictórica mais difícil de verbalizar quando comparado com o grupo com piores competências de leitura. Estes resultados são discutidos à luz do contributo das competências de leitura na facilitação em utilizar estratégias de dupla codificação para codificar a informação visuo-espacial em memória de trabalho

Morphological and molecular identification of the potato cyst

Summary – The potato cyst nematodes (PCN) Globodera rostochiensis and G. pallida pose one of the greatest threats to potato crops worldwide and are subject to strict quarantine regulations in many countries. The identification of these Globodera species based on morphology may be ambiguous due to the variability of the main morphological features and the overlapping of the standard parameters in these two species; thus, confirmation via molecular methods is recommended. Multiplex PCR with speciesspecificprimers (ITS5/PITSp4 + PITSr3) allows both species to be distinguished. However, despite the development of molecularidentification methods, the morphological approach remains useful as a complementary diagnostic technique. In this work, we report results of morphological and molecular analyses that were carried out in two Globodera species from Portuguese potato fields. The average morphometric values of 40 cysts and 40 second-stage juveniles were generally within the expected ranges for G. pallida and G. rostochiensis with some variations noted. Molecular analysis with multiplex PCR confirmed the morphometric identification. The present results confirmed the occurrence of two potato cyst nematode species, G. rostochiensis and G. pallida. Surprisingly, the analysis of soils from Portuguese potato fields detected a greater number of samples infested with G. pallida, which is contrary to expectation as G. rostochiensis has been considered the most widespread species in Portugal. The distinction between the two species is therefore essential in order to detect their presence in the country with a view to re-evaluating the control measures implemented so far and adopting more effective practices

species identification, distribution, and new host records in Portugal

Funding Information: This research was supported by the “Fundação para a Ciência e a Tecnologia” (FCT, Portugal) and the European Social Funds, through the “Programa Operacional Regional Centro”, under the Ph.D. fellowship 2020.05541.BD and through the R&D Unit, UIDB/04551/2020 (GREEN-IT—Bioresources for Sustainability). Acknowledgments Funding Information: This research was supported by the “Fundação para a Ciência e a Tecnologia” (FCT, Portugal) and the European Social Funds, through the “Programa Operacional Regional Centro”, under the Ph.D. fellowship 2020.05541.BD and through the R&D Unit, UIDB/04551/2020 (GREEN-IT—Bioresources for Sustainability). Publisher Copyright: Copyright © 2023 Rusinque, Camacho, Serra, Nóbrega and Inácio.Considered one of the most devastating plant parasitic nematodes worldwide, Meloidogyne spp. (commonly known as the root-knot nematodes (RKNs)) are obligate sedentary endoparasites that establish in the roots, causing hyperplasia and hypertrophy of surrounding cells, triggering the formation of galls. These galls will affect root development and physiology, leading to substantial yield losses. During 2017–2022, an extensive survey of Meloidogyne species was undertaken in Portugal (mainland and islands). A total of 1,071 samples were collected by the National Plant Protection Organization (DGAV) and private farmers from different regions of the country and were analysed at the Laboratory of Nematology (NemaINIAV). Samples in which the presence of Meloidogyne sp. was detected were used to perform bioassays to obtain females and juveniles for further studies. Since the accurate identification of RKNs is an important aspect of crop management, morphological and biochemical characterisation was performed. The most common morphological features were observed, showing consistency with previous descriptions of the genus. The biochemical identification using the esterase (EST) phenotype revealed the phenotypes of Meloidogyne arenaria, M enterolobi, M. hispanica, M. hapla, M. incognita, M javanica, and M. luci. Meloidogyne incognita and M. javanica were found to be the most prevalent species in the different regions followed by M. arenaria and M. hapla. This is the first distribution report performed in Portugal on RKNs, contributing to the development of management strategies and to updated information on the status of these pests in Europe.publishersversionpublishe

Root-Knot Nematode Species Associated with Horticultural Crops in the Island of Azores, Portugal

Plant-parasitic nematodes (PPN) are an economically important group of plant pests present throughout the world. In particular, root-knot nematodes (RKN), sedentary endoparasites of a wide variety of economically important hosts with the ability to survive in temperate regions. During 2020–2021 an extensive survey of Meloidogyne spp. was undertaken on the island of São Miguel Azores, Portugal. A total of 80 samples comprising 23 species of plants were collected from 13 localities in 4 districts of the island. Samples included field and greenhouse vegetable crops. Bioassays were carried out to obtain females and juveniles for morphological and biochemical characterization of the isolates. The observed morphological features showed high similarity and consistency with previous descriptions of the genus. Concerning the biochemical characterization, the esterase (EST) phenotype displayed the patterns described for M. incognita, M. arenaria, and M. javanica. Meloidogyne incognita was found to be the most prevalent species with respect to both natural host range and geographical distribution, followed by M. arenaria and M. javanica. This is the first field survey that assesses the species of root-knot nematodes associated with horticultural crops in the Azores Island, contributing additional information on the distribution of this genusinfo:eu-repo/semantics/publishedVersio

Nematode-Mycobiota interactions in Pine Wilt Disease

Pine wilt disease is one of the most important diseases for conifer forests worldwide. This complex disease involves the interaction between three primary biological elements - the plant parasitic nematode Bursaphelenchus xylophilus; the insect-vector Monochamus sp., and the host tree Pinus spp. – and other secondary elements such as endophytic bacteria and fungi. The development of B. xylophilus is strongly associated with fungi that colonize the declining trees, with special impact in their reproduction and number of individuals carried by the vector. In light of previous knowledge, we are focused in obtaining a detailed characterization of the structure and dynamics of the nematode-fungi interactions through culturable and non-culturable approaches with particular emphasis in metagenomics analysis. Our aim is to understand if nematode-associated mycobiota plays a key-role in the development of the disease, in interaction with nematode and insect-vector, and into which extend it can be used to disrupt the disease cycle

Potato Cyst Nematodes: geographical distribution, phylogenetic relationships and integrated pest management outcomes in Portugal

The identification and phylogenetic relationships of potato cyst nematodes (PCN) were studied to assess the potential value of geographical distribution information for integrated pest management of potato production in Portugal. This research focused on PCN species, Globodera pallida and Globodera rostochiensis. From 2013 until 2019, 748 soil samples from the rhizosphere of different potato cultivars were surveyed in the Portuguese mainland to detect and identify both species and track their location. PCN are widespread invasive species throughout Portugal. In fact, during the survey period an incidence of 22.5% was estimated for the tested samples. The patterns of infestation vary among regions, increasing from south to north, where PCN were first detected. Currently, both species are present in all potato producing regions of the country, with a greater incidence of G. pallida. Phytosanitary control measures are influencing to the observed results. The use of potato cultivars resistant to G. rostochiensis led to a decrease of this species but had no influence on G. pallida detections, which continues its reproduction freely since there are no effective resistant cultivars for this species. The relationship between the presence, infestation rate, spread and geographical distribution of PCN is discussed in terms of behavioral responses of the potato cultivars and the implications for developing new integrated crop protection measures

PineEnemy - Exploring the NEmatode-MYcobiota interactions in Pine Wilt Disease

Pine wilt disease (PWD) is one of the most important threats to conifer forests in Europe [1] and worldwide [2], causing severe economic and environmental damages. This complex disease results from the interaction between three biological elements: the pathogenic agent Bursaphelenchus xylophilus, also known as pinewood nematode (PWN); the insect-vector (cerambycid beetles of the genus Monochamus) [3], and the host tree, mostly from Pinus spp. [4]. In 1999, B. xylophilus was firstly identified in maritime pines (Pinus pinaster) in Portugal and in Europe [1, 5]. Despite a nationwide monitoring system, enforcement of strict phytosanitary measures and constraints implemented after PWN detection, this devastating problem has spread quickly in Portuguese mainland, Madeira Island [5] and Northern Spain [6]. As a migratory endoparasite, once inside susceptible tree, PWN has the ability to feed on the living parenchyma of the epithelial cells in the resin canals, causing a reduction in water flux and ultimately cessation of resin flow. In the later stages of the disease, PWN assumes a mycetophagous phase. The development of the PWN population appears to be strongly associated with fungi that colonize the declining trees [3]. Fungi harboured in weakened pines are seen as essential for the ongoing development and completion of the PWN life-cycle, affecting not only PWN reproduction [8] but also the number of individuals carried by the insect-vector [9-10]. Through a spatio-temporal analysis, PineEnemy will focus on the characterization of the structure and dynamics of the nematode-fungi interactions through culturable and non-culturable approaches with special emphasis in metagenomics analysis. Our aim is to understand if PWN-associated mycobiota plays a key-role in the development of PWD, in interaction with PWN and insect-vector, and into which extend can be targeted to disrupt the disease cycle