Which learning techniques supported by cognitive research do students use at secondary school? Prevalence and associations with students' beliefs and achievement.

Research in cognitive science has highlighted the effectiveness of several learning techniques, and a number of studies have analyzed their prevalence among university students and their relationship with academic achievement. In this study, we surveyed a large, heterogeneous sample of secondary school students to reveal how often they use research-supported techniques in comparison with other frequent techniques, and we analyzed the association between their study strategies and school achievement. We also assessed the associations between study techniques and several students' beliefs and attitudes toward learning (self-efficacy, goal orientation, control beliefs, growth mindset, and examination anxiety). Results showed that, except for distributed practice, only those techniques that are supported by previous research yielded an association with achievement, and they exhibited higher associations with self-efficacy, growth mindset, control beliefs, and learning goal orientation than non-supported techniques.

Spinocerebellar ataxia 38: structure-function analysis shows ELOVL5 G230V is proteotoxic, conformationally altered and a mutational hotspot.

Fatty acid elongase ELOVL5 is part of a protein family of multipass transmembrane proteins that reside in the endoplasmic reticulum where they regulate long-chain fatty acid elongation. A missense variant (c.689G>T p.Gly230Val) in ELOVL5 causes Spinocerebellar Ataxia subtype 38 (SCA38), a neurodegenerative disorder characterized by autosomal dominant inheritance, cerebellar Purkinje cell demise and adult-onset ataxia. Having previously showed aberrant accumulation of p.G230V in the Golgi complex, here we further investigated the pathogenic mechanisms triggered by p.G230V, integrating functional studies with bioinformatic analyses of protein sequence and structure. Biochemical analysis showed that p.G230V enzymatic activity was normal. In contrast, SCA38-derived fibroblasts showed reduced expression of ELOVL5, Golgi complex enlargement and increased proteasomal degradation with respect to controls. By heterologous overexpression, p.G230V was significantly more active than wild-type ELOVL5 in triggering the unfolded protein response and in decreasing viability in mouse cortical neurons. By homology modelling, we generated native and p.G230V protein structures whose superposition revealed a shift in Loop 6 in p.G230V that altered a highly conserved intramolecular disulphide bond. The conformation of this bond, connecting Loop 2 and Loop 6, appears to be elongase-specific. Alteration of this intramolecular interaction was also observed when comparing wild-type ELOVL4 and the p.W246G variant which causes SCA34. We demonstrate by sequence and structure analyses that ELOVL5 p.G230V and ELOVL4 p.W246G are position-equivalent missense variants. We conclude that SCA38 is a conformational disease and propose combined loss of function by mislocalization and gain of toxic function by ER/Golgi stress as early events in SCA38 pathogenesis.

AA-amyloidosis in cats (Felis catus) housed in shelters.

Systemic AA-amyloidosis is a protein-misfolding disease characterized by fibril deposition of serum amyloid-A protein (SAA) in several organs in humans and many animal species. Fibril deposits originate from abnormally high serum levels of SAA during chronic inflammation. A high prevalence of AA-amyloidosis has been reported in captive cheetahs and a horizontal transmission has been proposed. In domestic cats, AA-amyloidosis has been mainly described in predisposed breeds but only rarely reported in domestic short-hair cats. Aims of the study were to determine AA-amyloidosis prevalence in dead shelter cats. Liver, kidney, spleen and bile were collected at death in cats from 3 shelters. AA-amyloidosis was scored. Shedding of amyloid fibrils was investigated with western blot in bile and scored. Descriptive statistics were calculated. In the three shelters investigated, prevalence of AA-amyloidosis was 57.1% (16/28 cats), 73.0% (19/26) and 52.0% (13/25), respectively. In 72.9% of cats (35 in total) three organs were affected concurrently. Histopathology and immunofluorescence of post-mortem extracted deposits identified SAA as the major protein source. The duration of stay in the shelters was positively associated with a histological score of AA-amyloidosis (B = 0.026, CI95% = 0.007-0.046; p = 0.010). AA-amyloidosis was very frequent in shelter cats. Presence of SAA fragments in bile secretions raises the possibility of fecal-oral transmission of the disease. In conclusion, AA-amyloidosis was very frequent in shelter cats and those staying longer had more deposits. The cat may represent a natural model of AA-amyloidosis.

[Effectiveness of anti-CGRP monoclonal antibodies in the preventive treatment of migraine: A prospective study of 63 patients]. / Efectividad de anticuerpos monoclonales anti-PRGC en el tratamiento preventivo de la migraña: estudio prospectivo de 63 pacientes.

INTRODUCTION: Calcitonine Gen-Related Peptide (CGRP) established a revolution in migraine pathophysiology knowledge and has led to the development of new drugs specifically targeting this disease. METHODS: We present a prospective study in which 63 episodic and chronic migraine patients have been treated with anti-CGRP monoclonal antibodies describing their efficacy, security and relapses after their interruption. Response predictors have been analyzed such they can help us to create a better treatment plan. RESULTS: Average age was 48.3 ± 11.81 years old, 84.1% of them being women. The average was of 15.59 migraine days per month (MDM). 63.5% of all patients suffered chronic migraine. The initial dose of Erenumab in all patient was 70 mg subcutaneous. This was increased to 140 mg in 47.6% of the patients. An MDM reduction between 49.85% and 59.53% was obtained within three to twelve months from the start of treatment. Constipation was present in 17.5% of the patients and 4.8% suffered injection site reaction. The treatment was changed to Galcanezumab in 17.9% of the patients. After interrupting the treatment, 23 patients relapsed with a good response on reintroduction of the treatment. It was not possible to establish a clear response predictor, however a statistically significant increase in the number of days of improvement was observed with more MDM at baseline level (p = 0.002). CONCLUSIONS: Anti-CGRP monoclonal antibodies are effective, safe, and well tolerated drugs. We have observed that their discontinuation, in some cases can lead to frequent and early relapses so we strongly recommend to extend the treatment in those patients with a higher MDM.

CAPRIN1 haploinsufficiency causes a neurodevelopmental disorder with language impairment, ADHD and ASD.

We describe an autosomal dominant disorder associated with loss-of-function variants in the Cell cycle associated protein 1 (CAPRIN1; MIM*601178). CAPRIN1 encodes a ubiquitous protein that regulates the transport and translation of neuronal mRNAs critical for synaptic plasticity, as well as mRNAs encoding proteins important for cell proliferation and migration in multiple cell types. We identified 12 cases with loss-of-function CAPRIN1 variants, and a neurodevelopmental phenotype characterized by language impairment/speech delay (100%), intellectual disability (83%), attention deficit hyperactivity disorder (82%) and autism spectrum disorder (67%). Affected individuals also had respiratory problems (50%), limb/skeletal anomalies (50%), developmental delay (42%) feeding difficulties (33%), seizures (33%) and ophthalmologic problems (33%). In patient-derived lymphoblasts and fibroblasts, we showed a monoallelic expression of the wild-type allele, and a reduction of the transcript and protein compatible with a half dose. To further study pathogenic mechanisms, we generated sCAPRIN1+/- human induced pluripotent stem cells via CRISPR-Cas9 mutagenesis and differentiated them into neuronal progenitor cells and cortical neurons. CAPRIN1 loss caused reduced neuronal processes, overall disruption of the neuronal organization and an increased neuronal degeneration. We also observed an alteration of mRNA translation in CAPRIN1+/- neurons, compatible with its suggested function as translational inhibitor. CAPRIN1+/- neurons also showed an impaired calcium signalling and increased oxidative stress, two mechanisms that may directly affect neuronal networks development, maintenance and function. According to what was previously observed in the mouse model, measurements of activity in CAPRIN1+/- neurons via micro-electrode arrays indicated lower spike rates and bursts, with an overall reduced activity. In conclusion, we demonstrate that CAPRIN1 haploinsufficiency causes a novel autosomal dominant neurodevelopmental disorder and identify morphological and functional alterations associated with this disorder in human neuronal models.

Tenacious educational neuromyths: Prevalence among teachers and an intervention.

BACKGROUND: Several studies have revealed a common high prevalence of educational neuromyths among teachers from different countries. However, only one intervention aimed at reducing these beliefs among in-service teachers has been reported to date, and it was conducted in a non-naturalistic setting. PROCEDURE: In the present study, we administered a survey to measure the prevalence of common neuromyths in a large sample (n = 807) of primary and secondary teachers from 203 schools across Catalonia (Spain), and then we evaluated the impact that a 15-hour online course on neuroscience had on a sample of them as compared to a control group. MAIN FINDINGS: Results showed an initial distribution of neuromyth beliefs similar to those of previous studies and a large effect of the intervention on reducing their prevalence shortly after the training and in the long term. CONCLUSIONS: These findings provide evidence that an intervention addressed to in-service teachers that is low-cost and easy to implement can cast corrective effects that persist over time in neuromyth beliefs.

Abnormal Prothrombin (PIVKA-II) Expression in Canine Tissues as an Indicator of Anticoagulant Poisoning.

PIVKA-II is an aberrant form of vitamin K that has been demonstrated to be increased in human coagulation disorders and in some neoplastic diseases. In veterinary medicine, PIVKA-II levels have been demonstrated to be useful for distinguishing anticoagulant poisoning from other coagulopathies. In forensic pathology, there is the need to distinguish malicious poisoning from other causes of death and, in some cases, identifying poisoned dogs from dogs that died as a result of other coagulative disorders can be challenging. In this study, dogs that suddenly died underwent necropsy, histological examination, and toxicological analysis to establish cause of death. PIVKA-II immunohistochemical expression was evaluated on hepatic and renal tissues, and on neoplastic lesions when present. A total of 61 dogs were analyzed and anticoagulant substances were identified in 16 of the 61. Immunolabelling for PIVKA-II was observed in 27 of 61 cases in the liver and in 24 of 61 cases in the kidneys. Among the poisoned dogs, the PIVKA-II expression was present in the liver in 15 of 16 cases and in the kidneys in 16 of 16. Neoplastic lesions represented mainly by haemangiosarcomas were negative. This study highlights how the immunohistochemical expression of PIVKA-II in hepatic and renal tissues can be useful to identify patients with coagulative disorders due to clinical condition or the ingestion of anticoagulants substances.

Is project-based learning effective among kindergarten and elementary students? A systematic review.

Project-based learning (PjBL) is becoming widespread in many schools. However, the evidence of its effectiveness in the classroom is still limited, especially in basic education. The aim of the present study was to perform a systematic review of the empirical evidence assessing the impact of PjBL on academic achievement of kindergarten and elementary students. We also examined the quality of studies, their compliance with basic prerequisites for a successful result, and their fidelity towards the key elements of PBL intervention. For this objective, we conducted a literature search in January 2020. The inclusion criteria for the review required that studies followed a pre-post design with control group and measured quantitatively the impact of PBL on content knowledge of students. The final sample included eleven articles comprising data from 722 students. The studies yielded inconclusive results, had important methodological flaws, and reported insufficient or no information about important aspects of the materials, procedure and key requirements from students and instructors to guarantee the success of PjBL. Educational implications of these results are discussed.

A high-content drug screening strategy to identify protein level modulators for genetic diseases: A proof-of-principle in autosomal dominant leukodystrophy.

In genetic diseases, the most prevalent mechanism of pathogenicity is an altered expression of dosage-sensitive genes. Drugs that restore physiological levels of these genes should be effective in treating the associated conditions. We developed a screening strategy, based on a bicistronic dual-reporter vector, for identifying compounds that modulate protein levels, and used it in a pharmacological screening approach. To provide a proof-of-principle, we chose autosomal dominant leukodystrophy (ADLD), an ultra-rare adult-onset neurodegenerative disorder caused by lamin B1 (LMNB1) overexpression. We used a stable Chinese hamster ovary (CHO) cell line that simultaneously expresses an AcGFP reporter fused to LMNB1 and a Ds-Red normalizer. Using high-content imaging analysis, we screened a library of 717 biologically active compounds and approved drugs, and identified alvespimycin, an HSP90 inhibitor, as a positive hit. We confirmed that alvespimycin can reduce LMNB1 levels by 30%-80% in five different cell lines (fibroblasts, NIH3T3, CHO, COS-7, and rat primary glial cells). In ADLD fibroblasts, alvespimycin reduced cytoplasmic LMNB1 by about 50%. We propose this approach for effectively identifying potential drugs for treating genetic diseases associated with deletions/duplications and paving the way toward Phase II clinical trials.

In vitro dexamethasone treatment does not induce alternative ATM transcripts in cells from Ataxia-Telangiectasia patients.

Short term treatment with low doses of glucocorticoid analogues has been shown to ameliorate neurological symptoms in Ataxia-Telangiectasia (A-T), a rare autosomal recessive multisystem disease that mainly affects the cerebellum, immune system, and lungs. Molecular mechanisms underlying this clinical observation are unclear. We aimed at evaluating the effect of dexamethasone on the induction of alternative ATM transcripts (ATMdexa1). We showed that dexamethasone cannot induce an alternative ATM transcript in control and A-T lymphoblasts and primary fibroblasts, or in an ATM-knockout HeLa cell line. We also demonstrated that some of the reported readouts associated with ATMdexa1 are due to cellular artifacts and the direct induction of γH2AX by dexamethasone via DNA-PK. Finally, we suggest caution in interpreting dexamethasone effects in vitro for the results to be translated into a rational use of the drug in A-T patients.

An Attempt to Correct Erroneous Ideas Among Teacher Education Students: The Effectiveness of Refutation Texts.

There is sound evidence about the high prevalence of misconceptions about education among pre-service teachers. This trend continues after students complete the degree in education and once they are in the exercise of their profession. In fact, several studies show that these misconceptions are widespread among in-service teachers. Erroneous ideas about education may divert material and human resources to poor grounded methods and teaching tools, compromising the quality of education. Strategies to debunk misconceptions among future teachers, who may not have a firm position about many educational issues, might contribute to reversing this trend. The main goal of the present study was to assess the efficacy of refutation texts in the correction of misconceptions among pre-service teachers. As in previous studies with in-service teachers, refutation texts were effective in reducing participants' endorsement of misconceptions. But this effect was short-lived and did not affect participants' intention to use educational methods that are based on the misconceptions addressed in the refutation texts.

Can Research Contribute to Improve Educational Practice?

Teaching a diverse classroom is a challenging task. Educators are faced daily with the difficult task of making many decisions about how to educate each of their students. To do this, they mainly rely on their experience and that of their colleagues, their values, and thoughts. Although they are inherent and important in the profession of teaching, sometimes these resources may not suffice to make the best decisions, particularly when teachers are continuously bombarded with numerous fads and poorly grounded ideas about education. In this context, research-informed practice emerges as a promising approach. It involves integrating the professional expertise of teachers with the best evidence of researchers to make better decisions and improve education. However, for this approach to be successfully implemented, the gap between researchers and practitioners must first be bridged. The possible solutions to this challenge involve acting in three contexts: research production, research communication and research use. Specific measures in each of these contexts are described.

The effectiveness of refutation texts to correct misconceptions among educators.

Teachers around the world hold a considerable number of misconceptions about education. Consequently, schools can become epicenters for dubious practices that might jeopardize the quality of teaching and negatively influence students' wellbeing. The main objective of this study was to assess the efficacy of refutation texts in the correction of erroneous ideas among in-service teachers. The results of Experiment 1 indicate that refutation texts can be an effective means to correct false ideas among educators, even for strongly endorsed misconceptions. However, the results of Experiment 2 suggest that these effects may be short-lived. Furthermore, attempts to correct misconceptions seemed to have no beneficial effect on teachers' intention to implement educational practices that are based on those erroneous beliefs. The implications of these results for the training of preservice and in-service teachers are discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Allele-specific silencing as treatment for gene duplication disorders: proof-of-principle in autosomal dominant leukodystrophy.

Allele-specific silencing by RNA interference (ASP-siRNA) holds promise as a therapeutic strategy for downregulating a single mutant allele with minimal suppression of the corresponding wild-type allele. This approach has been effectively used to target autosomal dominant mutations and single nucleotide polymorphisms linked with aberrantly expanded trinucleotide repeats. Here, we propose ASP-siRNA as a preferable choice to target duplicated disease genes, avoiding potentially harmful excessive downregulation. As a proof-of-concept, we studied autosomal dominant adult-onset demyelinating leukodystrophy (ADLD) due to lamin B1 (LMNB1) duplication, a hereditary, progressive and fatal disorder affecting myelin in the CNS. Using a reporter system, we screened the most efficient ASP-siRNAs preferentially targeting one of the alleles at rs1051644 (average minor allele frequency: 0.45) located in the 3' untranslated region of the gene. We identified four siRNAs with a high efficacy and allele-specificity, which were tested in ADLD patient-derived fibroblasts. Three of the small interfering RNAs were highly selective for the target allele and restored both LMNB1 mRNA and protein levels close to control levels. Furthermore, small interfering RNA treatment abrogates the ADLD-specific phenotypes in fibroblasts and in two disease-relevant cellular models: murine oligodendrocytes overexpressing human LMNB1, and neurons directly reprogrammed from patients' fibroblasts. In conclusion, we demonstrated that ASP-silencing by RNA interference is a suitable and promising therapeutic option for ADLD. Moreover, our results have a broad translational value extending to several pathological conditions linked to gene-gain in copy number variations.

Long-term efficacy of docosahexaenoic acid (DHA) for Spinocerebellar Ataxia 38 (SCA38) treatment: An open label extension study.

INTRODUCTION: Spinocerebellar Ataxia 38 (SCA38) is caused by ELOVL5 gene mutation, with significant reduction of serum docosahexaenoic acid (DHA) levels. DHA supplementation has been proven effective at short-term follow-up. In the present paper, we evaluated long-term safety and efficacy of 600 mg/day oral DHA in SCA38 by a 2-year open label extension study. METHODS: Nine SCA38 patients underwent standardised clinical assessment at 62 (T1), 82 (T2) and 104 (T3) weeks, and compared to pre-treatment scores (T0). Brain 18-Fluorodeoxyglucose Positron Emission Tomography and electroneurography were performed at T0 and T3. RESULTS: We found a significant maintenance of clinical symptom improvement at each follow-up time-point (p < 0.001) as compared to T0, a sustained increase of cerebellar metabolism at T3 as compared to T0 (p = 0.013), and no worsening of neurophysiological parameters. No side effect was recorded. CONCLUSIONS: Long-term DHA supplementation is an eligible treatment for SCA38.

Content and source analysis of popular tweets following a recent case of diphtheria in Spain.

Background: Despite major progress in global vaccination coverage, immunization rates are falling, resulting in outbreaks of vaccine-preventable diseases. This study analyses content and source of the most popular tweets related to a recent case in Spain where an unvaccinated child contracted and later died from diphtheria. Understanding the characteristics of these tweets in the context of vaccination could inform efforts by health promotion professionals to increase their reach and impact. Methods: We extracted tweets containing keywords related to the diphtheria case (from 1 May to 15 July 2015). We explored the prevalence of terms relating to policy and misinformation and manually coded the 194 most popular tweets (retweeted 100 or more times) with regard to source, topic, tone and sentiment. Results: A total of 722 974 tweets were collected. Prevalence of terms relating to policy and misinformation increased at the onset of the case and after the death of the child. Popular tweets (194) were either pro-vaccination (58%) or neutral, with none classified as anti-vaccination. Popular topics included criticism towards anti-vaccination groups (35%) and effectiveness of immunization (22%). Popular tweets were informative (47%) or opinions (53%), which mainly expressed frustration (24%) or humour/sarcasm (23%). Popular Twitter accounts were newspaper and TV channels (15%), as well as individual journalists and authors of popular science (13.4%). Conclusions: Healthcare organizations could collaborate with popular journalists or news outlets and employ authors of popular science to disseminate health information on social media, while addressing public concerns and misinformation in accessible ways.

Mice harbouring a SCA28 patient mutation in AFG3L2 develop late-onset ataxia associated with enhanced mitochondrial proteotoxicity.

Spinocerebellar ataxia 28 is an autosomal dominant neurodegenerative disorder caused by missense mutations affecting the proteolytic domain of AFG3L2, a major component of the mitochondrial m-AAA protease. However, little is known of the underlying pathogenetic mechanisms or how to treat patients with SCA28. Currently available Afg3l2 mutant mice harbour deletions that lead to severe, early-onset neurological phenotypes that do not faithfully reproduce the late-onset and slowly progressing SCA28 phenotype. Here we describe production and detailed analysis of a new knock-in murine model harbouring an Afg3l2 allele carrying the p.Met665Arg patient-derived mutation. Heterozygous mutant mice developed normally but adult mice showed signs of cerebellar ataxia detectable by beam test. Although cerebellar pathology was negative, electrophysiological analysis showed a trend towards increased spontaneous firing in Purkinje cells from heterozygous mutants with respect to wild-type controls. As homozygous mutants died perinatally with evidence of cardiac atrophy, for each genotype we generated mouse embryonic fibroblasts (MEFs) to investigate mitochondrial function. MEFs from mutant mice showed altered mitochondrial bioenergetics, with decreased basal oxygen consumption rate, ATP synthesis and mitochondrial membrane potential. Mitochondrial network formation and morphology was altered, with greatly reduced expression of fusogenic Opa1 isoforms. Mitochondrial alterations were also detected in cerebella of 18-month-old heterozygous mutants and may be a hallmark of disease. Pharmacological inhibition of de novo mitochondrial protein translation with chloramphenicol caused reversal of mitochondrial morphology in homozygous mutant MEFs, supporting the relevance of mitochondrial proteotoxicity for SCA28 pathogenesis and therapy development.

Spinocerebellar Ataxia Tethering PCR: A Rapid Genetic Test for the Diagnosis of Spinocerebellar Ataxia Types 1, 2, 3, 6, and 7 by PCR and Capillary Electrophoresis.

Spinocerebellar ataxia (SCA) types 1, 2, 3, 6, and 7, associated with a (CAG)n repeat expansion in coding sequences, are the most prevalent autosomal dominant ataxias worldwide (approximately 60% of the cases). In addition, the phenotype of SCA2 expansions has been now extended to Parkinson disease and amyotrophic lateral sclerosis. Their diagnosis is currently based on a PCR to identify small expanded alleles, followed by a second-level test whenever a false normal homozygous or a CAT interruption in SCA1 needs to be verified. Next-generation sequencing still does not allow efficient detection of these repeats. Here, we show the efficacy of a novel, rapid, and cost-effective method to identify and size pathogenic expansions in SCA1, 2, 3, 6, and 7 and recognize large alleles or interruptions without a second-level test. Twenty-five healthy controls and 33 expansion carriers were analyzed: alleles migrated consistently in different PCRs and capillary runs, and homozygous individuals were always distinguishable from heterozygous carriers of both common and large (>100 repeats) pathogenic CAG expansions. Repeat number could be calculated counting the number of peaks, except for the largest SCA2 and SCA7 alleles. Interruptions in SCA1 were always visible. Overall, our method allows a simpler, cost-effective, and sensibly faster SCA diagnostic protocol compared with the standard technique and to the still unadapted next-generation sequencing.

Docosahexaenoic acid is a beneficial replacement treatment for spinocerebellar ataxia 38.

OBJECTIVE: Spinocerebellar ataxia 38 (SCA38) is caused by mutations in the ELOVL5 gene, which encodes an elongase involved in the synthesis of polyunsaturated fatty acids, including docosahexaenoic acid (DHA). As a consequence, DHA is significantly reduced in the serum of SCA38 subjects. In the present study, we evaluated the safety of DHA supplementation, its efficacy for clinical symptoms, and changes of brain functional imaging in SCA38 patients. METHODS: We enrolled 10 SCA38 patients, and carried out a double-blind randomized placebo-controlled study for 16 weeks, followed by an open-label study with overall 40-week DHA treatment. At baseline and at follow-up visit, patients underwent standardized clinical assessment, brain 18-fluorodeoxyglucose positron emission tomography, electroneurography, and ELOVL5 expression analysis. RESULTS: After 16 weeks, we showed a significant pre-post clinical improvement in the DHA group versus placebo, using the Scale for the Assessment and Rating of Ataxia (SARA; mean difference [MD] = +2.70, 95% confidence interval [CI] = +0.13 to + 5.27, p = 0.042). At 40-week treatment, clinical improvement was found significant by both SARA (MD = +2.2, 95% CI = +0.93 to + 3.46, p = 0.008) and International Cooperative Ataxia Rating Scale (MD = +3.8, 95% CI = +1.39 to + 6.41, p = 0.02) scores; clinical data were corroborated by significant improvement of cerebellar hypometabolism (statistical parametric mapping analyses, false discovery rate corrected). We also showed a decreased expression of ELOVL5 in patients' blood at 40 weeks as compared to baseline. No side effect was recorded. INTERPRETATION: DHA supplementation is a safe and effective treatment for SCA38, showing an improvement of clinical symptoms and cerebellar hypometabolism. Ann Neurol 2017;82:615-621.

Is crossed laterality associated with academic achievement and intelligence? A systematic review and meta-analysis.

Over the last century, sporadic research has suggested that people whose hand, eye, foot, or ear dominances are not consistently right- or left-sided are at special risk of suffering academic difficulties. This phenomenon is known as crossed laterality. Although the bulk of this research dates from 1960's and 1970's, crossed laterality is becoming increasingly popular in the area of school education, driving the creation of several interventions aimed at restoring or consolidating lateral dominance. However, the available evidence is fragmentary. To determine the impact of crossed laterality on academic achievement and intelligence, we conducted a systematic review and meta-analysis of articles published since 1900. The inclusion criteria for the review required that studies used one or more lateral preference tasks for at least two specific parts of the body; they included a valid measure of crossed laterality; they measured the impact of crossed laterality on academic achievement or intelligence; and they included participants between 3 and 17 years old. The final sample included 26 articles that covered a total population of 3578 children aged 5 to 12. Taken collectively, the results of these studies do not support the claim that there is a reliable association between crossed laterality and either academic achievement or intelligence. Along with this, we detected important shortcomings in the literature, such as considerable heterogeneity among the variables used to measure laterality and among the tasks utilized to measure the outcomes. The educational implications of these results are discussed.