Testing the relationship between lateralization on sequence-based motor tasks and language laterality using an online battery

In a study of patterns of language laterality in left-and right-handers, Woodhead et al.(2021) noted that several tasks showed no bias to the left-hemisphere in left-handed individuals. This might appear to suggest that these functions were mediated by the two hemispheres working together equally in left-handers. Here, I consider an alternative possibility: that individuals show lateral bias on these tasks, but the bias can occur to either left or right. Further analysis of the distributions of data from individuals in Woodhead et al is compared with simulated data. The pattern of results suggests that the impression of bilateral language processing may be an artefact of reliance on group data: even though the group mean does not differ from zero, a high proportion of individuals are biased to left or right.

Recent studies in psychology have documented how analytic flexibility can result in different results from the same dataset. Here we demonstrate a package in the R programming language, DeclareDesign, which uses simulated data to diagnose the properties of analytic designs. To illustrate features of the package, we contrast two analyses of a randomised controlled trial (RCT) of GraphoGame, an intervention to help children learn to read. The initial analysis (NFER) found that the intervention was ineffective, but a subsequent reanalysis (Cambridge) concluded that GraphoGame significantly improved children’s reading. With DeclareDesign we can simulate data where the truth is known, and thus can identify which analysis is optimal for estimating the intervention effect, using “diagnosands”, including bias, precision, and power. The simulations showed that the NFER analysis accurately estimated intervention effects, whereas selection of a subset of data in the Cambridge analysis introduced substantial bias, overestimating the effect sizes. This problem was exacerbated by inclusion of multiple outcome measures in the Cambridge analysis. Much has been written about the dangers of performing reanalyses of data from RCTs that violate the randomisation of participants to conditions; simulated data make this message clear and quantify the extent to which such practices introduce bias. The simulations confirm the original NFER conclusion that the intervention has no benefit over “business as usual”. In this tutorial we demonstrate several features of DeclareDesign; this package can simulate observational and well as experimental research …

Proceedings of the Royal Society B

In October 2017, Proceedings of the Royal Society B published an article by Le Floch & Ropars [1] claiming that dyslexia could be caused by a visual anomaly that led to confusion between images from the two eyes when reading letters. This article attracted considerable media attention, with an Altmetric score of 829, including coverage by 83 news outlets, and has subsequently been cited in promotional material for devices that are designed to ameliorate the problem. A number of international experts raised concerns about the study on the postpublication peer review site PubPeer [2], but this has not led to any moderation of the claims made for therapeutic implications of the study. Given that our view is that the study suffers from methodological, interpretive and ethical problems that should have precluded publication, we are grateful to the editors for providing this opportunity to document these issues.

Neurobiology of Language

In this exploratory study we compare and contrast two methods for deriving a laterality index (LI) from functional magnetic resonance imaging (fMRI) data: the weighted bootstrapped mean from the Laterality Toolbox (toolbox method), and a novel method that uses subtraction of activations from homologous regions in left and right hemispheres to give an array of difference scores (mirror method). Data came from 31 individuals who had been selected to include a high proportion of people with atypical laterality when tested with functional transcranial Doppler ultrasound (fTCD). On two tasks, word generation and semantic matching, the mirror method generally gave better agreement with fTCD laterality than the toolbox method, both for individual regions of interest, and for a large region corresponding to the middle cerebral artery. LI estimates from this method had much smaller confidence intervals (CIs) than …

Background: Organisations known as paper mills charge authors to place fraudulent papers in the academic literature. Publishers have been slow to tackle the problem, but are now starting to devise methods for identifying paper mill products. However, little attention has been paid to the topic of complicit editors, who can take over special issues of journals and then publish many fraudulent articles. To date, activities of such editors have been documented by a handful of sleuths on social media and on the website PubPeer. This paper reports a descriptive study that documents more systematically the presence of “red flags” indicative of paper mill activity in special issues from the Wiley-Hindawi Open Access publishing partnership.Methods: A spreadsheet was created from the Hindawi website with records for all published articles during 2022. Initial analysis focused on initial Editor Response Time (RT) in ten journals that had been identified by sleuths as having high rates of problematic papers. In a second step, the whole dataset was scrutinized to identify editors who had handled at least 10 articles. These were divided into those who had had at least one PubPeer comment flagging dubious content or citations, and those with no PubPeer comments.Results: A cutoff of 22 days was identified as corresponding to the 2nd percentile of Editor RT for regular articles not in special issues. Plots show that in the 10 selected journals, some special issues have 50% or more of Editor RTs below this cutoff, raising questions as to whether an appropriate peer review process had taken place. Editors with articles flagged on PubPeer processed significantly …

Fraudulent published papers used to be thought to be rare, but in recent years there has been growing awareness of coordinated activities by organizations that charge authors a fee to plant articles in reputable journals. These are known as paper mills. We reflect here on how Mind, Brain and Education suffered from such an attack in 2022 and 2023, discussing what we have learnt from this experience about how paper mills might operate in social sciences, how to spot signs that an article is fraudulent, and what steps might be taken to prevent such attacks in future.

Journal of Child Language

This study reports on the feasibility of using the Test of Complex Syntax- Electronic (TECS-E), as a self-directed app, to measure sentence comprehension in children aged 4 to 5 ½ years old; how testing apps might be adapted for effective independent use; and agreement levels between face-to-face supported computerized and independent computerized testing with this cohort. A pilot phase was completed with 4 to 4;06-year-old children, to determine the appropriate functional app features required to facilitate independent test completion. Following the integration of identified features, children completed the app independently or with adult support (4–4;05 (n = 22) 4;06–4;11 months (n = 55) and 5 to 5;05 (n = 113)) and test re-test reliability was examined. Independent test completion posed problems for children under 5 years but for those over 5, TECS-E is a reliable method to assess children’s understanding of …

Pilot and Feasibility Studies

BackgroundCognitive problems associated with dementia affect a large proportion of older adults living in residential care. Knowledge of cognitive impairments is important for providing person-centred care (PCC). The impact of specific cognitive impairments on residents’ needs is often overlooked in dementia training and information about residents’ individual cognitive profiles are frequently underspecified in care-plans, potentially undermining the delivery of PCC. This can lead to reduced resident quality of life and increased distressed behaviours—a major cause of staff stress and burnout. The COG-D package was developed to fill this gap. Daisies provide a visual representation of a resident’s individual cognitive strengths and weaknesses in a colourful flower (Daisy) representing five cognitive domains. By viewing a resident’s Daisy, care-staff can flexibly adjust in-the-moment care-decisions and can consult …

Human Brain Mapping

We consider how analysis of brain lateralization using functional transcranial Doppler ultrasound (fTCD) data can be brought in line with modern statistical methods typically used in functional magnetic resonance imaging (fMRI). Conventionally, a laterality index is computed in fTCD from the difference between the averages of each hemisphere's signal within a period of interest (POI) over a series of trials. We demonstrate use of generalized linear models (GLMs) and generalized additive models (GAM) to analyze data from individual participants in three published studies (N = 154, 73 and 31), and compare this with results from the conventional POI averaging approach, and with laterality assessed using fMRI (N = 31). The GLM approach was based on classic fMRI analysis that includes a hemodynamic response function as a predictor; the GAM approach estimated the response function from the data, including a …

Child development

Handedness has been studied for association with language‐related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non‐right‐handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex‐matched controls identified from 10 distinct cohorts (age range 6–19 years old; European ethnicity) using a priori set criteria. A meta‐analysis (Ncases = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06–1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions.

IMpact

Near-peer mentoring has been used within Higher Education settings for several years to support students through their transition from secondary to tertiary education. The goals of mentorship centre around support, development, and retention of students who themselves feel satisfied, fully engaged in their learning environment and are socially responsible. Having a more experienced mentor (near-peer) with lived experience can help guide and engage mentees providing measurable benefits to both, with mentees gaining a greater degree of social support and insight into their future learning requirements to help navigate them through their academic journey, and mentors enhancing their interpersonal skills such as communication, listening, networking and leadership. With the growing evidence that near-peer mentoring benefits all involved, it is perhaps unsurprising it is becoming commonplace in Higher Education. However, for these benefits to be recognised it is essential that behind the scenes there are dedicated staff who develop and support the peer mentoring programme ensuring they are fit for purpose. The following tips draw on experience of near-peer mentoring within a medical education setting but are considered applicable and transferable to other Higher Education programmes. Fundamental to all successful near-peer mentoring schemes should be clearly defined processes for selection, training (Tips 1-4) and programme implementation (Tips 5-9). Continuous reflection, improvement, and the importance of near-peer mentor recognition (Tip 10) should also be at the forefront of any near-peer mentoring scheme.

Laterality

Laterality indices (LIs) quantify the left-right asymmetry of brain and behavioural variables and provide a measure that is statistically convenient and seemingly easy to interpret. Substantial variability in how structural and functional asymmetries are recorded, calculated, and reported, however, suggest little agreement on the conditions required for its valid assessment. The present study aimed for consensus on general aspects in this context of laterality research, and more specifically within a particular method or technique (i.e., dichotic listening, visual half-field technique, performance asymmetries, preference bias reports, electrophysiological recording, functional MRI, structural MRI, and functional transcranial Doppler sonography). Experts in laterality research were invited to participate in an online Delphi survey to evaluate consensus and stimulate discussion. In Round 0, 106 experts generated 453 statements …

IMpact

Near-peer mentoring has been used within Higher Education settings for several years to support students through their transition from secondary to tertiary education. The goals of mentorship centre around support, development, and retention of students who themselves feel satisfied, fully engaged in their learning environment and are socially responsible. Having a more experienced mentor (near-peer) with lived experience can help guide and engage mentees providing measurable benefits to both, with mentees gaining a greater degree of social support and insight into their future learning requirements to help navigate them through their academic journey, and mentors enhancing their interpersonal skills such as communication, listening, networking and leadership. With the growing evidence that near-peer mentoring benefits all involved, it is perhaps unsurprising it is becoming commonplace in Higher Education. However, for these benefits to be recognised it is essential that behind the scenes there are dedicated staff who develop and support the peer mentoring programme ensuring they are fit for purpose. The following tips draw on experience of near-peer mentoring within a medical education setting but are considered applicable and transferable to other Higher Education programmes. Fundamental to all successful near-peer mentoring schemes should be clearly defined processes for selection, training (Tips 1-4) and programme implementation (Tips 5-9). Continuous reflection, improvement, and the importance of near-peer mentor recognition (Tip 10) should also be at the forefront of any near-peer mentoring scheme.

Those who work in allied health professions and education aim to make people’s lives better. Often, however, it is hard to know how effective this work has been: would change have occurred if there was no intervention? Is it possible we are doing more harm than good? To answer these questions and develop a body of knowledge about what works, we need to evaluate interventions. Objective intervention research is vital to improve outcomes, but this is a complex area, where it is all too easy to misinterpret evidence. This book uses practical examples to increase awareness of the numerous sources of bias that can lead to mistaken conclusions when evaluating interventions. The focus is on quantitative research methods, and exploration of the reasons why those both receiving and implementing intervention behave in the ways they do. Evaluating What Works: Intuitive Guide to Intervention Research for Practitioners illustrates how different research designs can overcome these issues, and points the reader to sources with more in-depth information. This book is intended for those with little or no background in statistics, to give them the confidence to approach statistics in published literature with a more critical eye, recognise when more specialist advice is needed, and give them the ability to communicate more effectively with statisticians. Key Features: Strong focus on quantitative research methods Complements more technical introductions to statistics Provides a good explanation of how quantitative studies are designed, and what biases and pitfalls they can involve

Authorea Preprints

Three years ago I wrote an open letter to Susan Greenfiel d, asking her to please stop claiming there is a link between autism and use of digital media. It’s never pleasant criticizing a colleague, and since my earlier blogpost I’ve held back from further comment, hoping that she might refrain from making claims about autism, and/or that interest in her views would just die down. But now she's back, reiterating the claims in a new book and TV interview, and I can remain silent no longer.Greenfield featured last week as the subject of a BBC interview in the series Hard Talk. The interviewer, Stephen Sackur, asked her specifically if she really believed her claims that exposure to modern digital media–the internet, video games, social media–were damaging to children’s development. Greenfield stressed that she did: although she herself had not done direct research on the internet/brain impact link, there was ample research to persuade her it was real. Specifically, she stated:“.. in terms of the evidence, anyone is welcome to look at my website, and it’s been up there for the last year. There’s 500 peer-reviewed papers in support of the possible problematic effects.”

We first describe the phenomenon of the academic paper mill, a kind of large-scale fraud in which authors pay to have work published in reputable journals. We give examples of some known paper mills and discuss ‘red flags’ that characterise their outputs. Most of the early examples were in biomedical and computational sciences and so paper mills are less familiar to many psychologists. In the next section, we describe a broker company/paper mill, Tanu. pro, discovered by the first author, which was identified by the use of fake email addresses. This paper mill placed six outputs in the Journal of Community Psychology, a reputable journal from a mainstream publisher. We look in detail at these papers and describe the features that confirm that malpractice was involved in publication. In five cases there was circumstantial evidence of tampering with the peer review process coupled with lack of editorial oversight. These papers have now been retracted. In a final section, we discuss the need for editors of psychology journals to be aware of potential targeting by paper mills and recommend editorial procedures to counteract these

Laterality

Laterality is considered relevant to performance in combat sports with particular emphasis being placed on fighters’ handedness and combat stance. Such approach, however, may fall too short to understand the role of laterality in sports where fighters are allowed to use their hands and feet standing and on the ground. Here, we referred to grappling sports (i) to estimate lateral preferences in selected combat situations and (ii) to test for an association between those preferences and common measures of hand and foot preference. Based on the responses of 135 experienced grapplers who participated in an online questionnaire lateral preference, at the group-level, was revealed in 12 out of 18 combat situations. At an item-level, common measures of lateral preference and grappling-specific lateral preference were related in three out of 36 conditions (footedness only, not handedness). Across items, scores in a …

Laterality

Cerebral lateralization of oral language has been investigated in a plethora of studies and it is well established that the left hemisphere is dominant for production tasks in the majority of individuals. However, few studies have focused on written language and even fewer have sampled left-handers. Writing comprises language and motor components, both of which contribute to cerebral activation, yet previous research has not disentangled. The aim of this study was to disentangle the language and motor components of writing lateralization. This was achieved through the comparison of cerebral activation during (i) written word generation and (ii) letter copying, as assessed by functional Transcranial Doppler (fTCD) ultrasound. We further assessed cerebral laterality of oral language. The sample was balanced for handedness. We preregistered the hypotheses that (i) cerebral lateralization of the linguistic component …

Laterality

The study looked into the hemispheres’ involvement in emotional word encoding. It combined brain activity measures (ERPs) with behavioural data during the affective categorization task in the divided visual field presentation paradigm. Forty healthy right-handed student volunteers took part in the study, in which they viewed and evaluated 33 positive and 33 negative emotional adjectives presented to either the left or right visual field. We observed a marginally significant effect on the earlier time window (220–250 ms, the P2 component) with higher mean amplitudes evoked to the words presented to the right hemisphere, and then a strong effect on the 340–400 ms (the P3) with a reversed pattern (higher amplitudes for words presented to the left hemisphere). The latter effect was also visible in the error rates and RTs, with better overall performance for adjectives presented to the left hemisphere. There was also …

Laterality

Several factors affect the development of lateralization such as hormones and light exposure during early development. Laterality also often correlates with other behavioral traits. To examine whether there is a common mechanism underlying the development of laterality and other behaviors, we manipulated laterality by exposing embryos of the Western rainbowfish (Melatotaenia australis) to light or continuous darkness during early development and determined whether a shift in laterality was associated with a change in behavior in a novel environment test at two different ages. We found that exposing eggs to darkness led to offspring that displayed significantly less lateralized behavior in the mirror test two weeks after hatching than offspring from eggs exposed to light. Interestingly, the effects of rearing condition were lost by 3 months of age. These data suggest that exposure to light can influence laterality very …

Laterality

The notion of an increased incidence of left handers among architects and visual artists has inspired both scientific theory building and popular discussion. However, a systematic exploration of the available publications provides, at best, modest evidence for this claim. The present preregistered observational study was designed to reinvestigate the postulated association by examining hand preference of visual artists who share their artistic activities as short video clips (“reels”) on the social media platform Instagram. Determining individual hand preference based on five reels for each of N = 468 artists, we identified 42 (8.97%) left handers, suggesting an incidence which is below but statistical comparable to the 10.6% expected for the general population (χ2 = 1.30; p = .25; Cohen’s w = 0.05). Also, we did not find any support for the notion that the art created by left-handed artists is of higher quality than art …

Laterality

The Chimeric Face Test (CFT) is a widely used behavioral measure of degree of lateralization for emotion processing. The Pictures of Facial Affect (Ekman, 1976 [Pictures of facial affect. Consulting Psychologists Press.]) have often been used to create chimeras for this task but have widely been critiqued due to lack of ethnic diversity and small stimuli numbers. In this brief study participants (N = 45) completed two Chimeric Face Tests, one using the Pictures of Facial Affect and one using the NimStim facial stimuli (Tottenham et al., 2009 [The NimStim set of facial expressions: Judgments from untrained research participants. Psychiatry Research, 168(3), 242–249]). The laterality scores were compared across measures. The results show the two measures are related; laterality quotients showed a strong correlation between the two tasks. Participants showed a left-visual field bias on both tasks, indicative of a right …

Laterality

Whereas a rightward bump is more likely than a leftward bump when walking through a doorway, investigations into potential similar asymmetries for drivers are limited. The research presented here aims to determine the influence of innate lateral spatial biases when driving. Data from the Strategic Highway Research Program Naturalistic Driving Study (SHRP 2 NDS) and a driving simulation were used to address our research questions. Data points from SHRP 2 were aggregated within relevant variables (e.g., left/right obstacles). In the simulation, participants drove in ways that were consistent with their everyday driving in urban and rural environments. Collision frequency, collision severity and average lateral lane position were analyzed with rightward biases throughout both analyzes. SHRP 2 data indicated greater likelihoods of collisions when vehicles crossed the right line/edge of the road and when making a …

Laterality

Whereas a rightward bump is more likely than a leftward bump when walking through a doorway, investigations into potential similar asymmetries for drivers are limited. The research presented here aims to determine the influence of innate lateral spatial biases when driving. Data from the Strategic Highway Research Program Naturalistic Driving Study (SHRP 2 NDS) and a driving simulation were used to address our research questions. Data points from SHRP 2 were aggregated within relevant variables (e.g., left/right obstacles). In the simulation, participants drove in ways that were consistent with their everyday driving in urban and rural environments. Collision frequency, collision severity and average lateral lane position were analyzed with rightward biases throughout both analyzes. SHRP 2 data indicated greater likelihoods of collisions when vehicles crossed the right line/edge of the road and when making a …

Laterality

Several factors affect the development of lateralization such as hormones and light exposure during early development. Laterality also often correlates with other behavioral traits. To examine whether there is a common mechanism underlying the development of laterality and other behaviors, we manipulated laterality by exposing embryos of the Western rainbowfish (Melatotaenia australis) to light or continuous darkness during early development and determined whether a shift in laterality was associated with a change in behavior in a novel environment test at two different ages. We found that exposing eggs to darkness led to offspring that displayed significantly less lateralized behavior in the mirror test two weeks after hatching than offspring from eggs exposed to light. Interestingly, the effects of rearing condition were lost by 3 months of age. These data suggest that exposure to light can influence laterality very …

Laterality

Several factors affect the development of lateralization such as hormones and light exposure during early development. Laterality also often correlates with other behavioral traits. To examine whether there is a common mechanism underlying the development of laterality and other behaviors, we manipulated laterality by exposing embryos of the Western rainbowfish (Melatotaenia australis) to light or continuous darkness during early development and determined whether a shift in laterality was associated with a change in behavior in a novel environment test at two different ages. We found that exposing eggs to darkness led to offspring that displayed significantly less lateralized behavior in the mirror test two weeks after hatching than offspring from eggs exposed to light. Interestingly, the effects of rearing condition were lost by 3 months of age. These data suggest that exposure to light can influence laterality very …

Laterality

Role-differentiated bimanual manipulation (RDBM) is a complex behaviour requiring the complementary movement of two hands to achieve a common goal. We investigated the relation of RDBM speed (time to complete a successful RDBM) with a hand preference for acquiring objects (early right, late right, left, no preference), toy type (simple/difficult), age (9-14 months), and hand (right/left) used to perform the RDBM. Changes in RDBM speed across age were examined across different hand preference groups for RDBMs performed on simple toys using the right hand. The analysis revealed that early-right preference infants had a steeper slope than the no preference/left-preference infants. The same was true for right-preference infants (early- and late-) for RDBMs performed on difficult toys using the right hand. A mixed ANOVA revealed that there were decreases in RDBM times across age, therefore infants are …

Laterality

Whereas a rightward bump is more likely than a leftward bump when walking through a doorway, investigations into potential similar asymmetries for drivers are limited. The research presented here aims to determine the influence of innate lateral spatial biases when driving. Data from the Strategic Highway Research Program Naturalistic Driving Study (SHRP 2 NDS) and a driving simulation were used to address our research questions. Data points from SHRP 2 were aggregated within relevant variables (e.g., left/right obstacles). In the simulation, participants drove in ways that were consistent with their everyday driving in urban and rural environments. Collision frequency, collision severity and average lateral lane position were analyzed with rightward biases throughout both analyzes. SHRP 2 data indicated greater likelihoods of collisions when vehicles crossed the right line/edge of the road and when making a …

Laterality

The Chimeric Face Test (CFT) is a widely used behavioral measure of degree of lateralization for emotion processing. The Pictures of Facial Affect (Ekman, 1976 [Pictures of facial affect. Consulting Psychologists Press.]) have often been used to create chimeras for this task but have widely been critiqued due to lack of ethnic diversity and small stimuli numbers. In this brief study participants (N = 45) completed two Chimeric Face Tests, one using the Pictures of Facial Affect and one using the NimStim facial stimuli (Tottenham et al., 2009 [The NimStim set of facial expressions: Judgments from untrained research participants. Psychiatry Research, 168(3), 242–249]). The laterality scores were compared across measures. The results show the two measures are related; laterality quotients showed a strong correlation between the two tasks. Participants showed a left-visual field bias on both tasks, indicative of a right …

Laterality

Laterality indices (LIs) quantify the left-right asymmetry of brain and behavioural variables and provide a measure that is statistically convenient and seemingly easy to interpret. Substantial variability in how structural and functional asymmetries are recorded, calculated, and reported, however, suggest little agreement on the conditions required for its valid assessment. The present study aimed for consensus on general aspects in this context of laterality research, and more specifically within a particular method or technique (i.e., dichotic listening, visual half-field technique, performance asymmetries, preference bias reports, electrophysiological recording, functional MRI, structural MRI, and functional transcranial Doppler sonography). Experts in laterality research were invited to participate in an online Delphi survey to evaluate consensus and stimulate discussion. In Round 0, 106 experts generated 453 statements …

Laterality

Meta-analyses have shown subtle, group-level asymmetries of spatial attention in adults favouring the left hemispace (pseudoneglect). However, no meta-analysis has synthesized data on children. We performed a random-effects meta-analysis of spatial biases in children aged ≤16 years. Databases (PsycINFO, Web of Science & Scopus) and pre-print servers (bioRxiv, medRxiv & PsyArXiv) were searched for studies involving typically developing children with a mean age of ≤16, who were tested using line bisection. Thirty-three datasets, from 31 studies, involving 2101 children, were included. No bias was identified overall, but there was a small leftward bias in a subgroup where all children were aged ≤16. Moderator analysis found symmetrical neglect, with right-handed actions resulting in right-biased bisections, and left-handed actions in left-biased bisections. Bisections were more leftward in studies with a …

Laterality

We present a postnatal evaluation of skull developmental signaling in small African pangolin emphasizing structural, and cognitive trend in ontogeny for assessment of developmental instability, proper identification and classification, forty digitally processed skulls and foramen magnum from different geo-locations were assessed for asymmetry, foramen magnum shape and modularity using geometric and Elliptical Fourier analyses. Multivariate analysis of regression demonstrated low (p < 0.5) but directional fluctuating asymmetry (F1539 = 3.4045, F882 = 3.2665, dorsal and ventral views). Allometric trajectories followed rostrocaudal, caudolateral directions; Intercepts for shape/size predictions were parallel. Mahalanobis distances between centroids (2.42) were significant (p < 0.01). The variance-covariance matrix in ontogeny lies between 0.0017 and 0.56. Foramen magnum outline descriptors by incremental …

Laterality

Studies have highlighted an association between motor laterality and speech production laterality. It is thought that common demands for sequential processing may underlie this association. However, most studies in this area have relied on relatively small samples and have infrequently explored the reliability of the tools used to assess lateralization. We, therefore, established the validity and reliability of an online battery measuring sequence-based motor laterality and language laterality before exploring the associations between laterality indices on language and motor tasks. The online battery was completed by 621 participants, 52 of whom returned to complete the battery a second time. The three motor tasks included in the battery showed good between-session reliability (r ≥ .78) and were lateralized in concordance with hand preference. The novel measure of speech production laterality was left …

Laterality

Indications of laterall biases favouring left-handers have been found in various sports; especially interactive sports where the athletes have limited time to react to incoming objects. The aim of this study was therefore to explore whether any lateral biases exist in handball by examining 7-meter shots. A total of 6846 7-meter throws from 240 7-meter shooters across four seasons in the semi-professional Icelandic elite handball division (male and female) were analyzed. Out of the 240 7-meter shooters, of which 151 were male and 89 were female, 22% were left-handed (22% of the males and 20% of the females). The left-handed 7-meter shooters took a disproportionate number of the 7-meter shots, with left-handed shooters performing 29% of the 7-meter shots (27% in the male league and 33% in the female league). The results of a Bayesian two-level analysis indicated that left-handedness is not associated with …

Laterality

Evidence suggests that language processing in bilinguals is less left-lateralized than in monolinguals. We explored dual-task decrement (DTD) for mono-, bi- and multilinguals in a verbal-motor dual-task paradigm. We expected monolinguals to show greater DTD than bilingual participants, who would show greater DTD than multilingual participants. Fifty right-handed participants (18 monolingual, 16 bilingual, 16 multilingual) completed verbal fluency and manual motor tasks in isolation and concurrently. Tasks were completed twice in isolation (left-handed, right-handed) and twice as dual-tasks (left-handed, right-handed); participants’ motor-executing hands served proxy for hemispheric activation. Results supported the hypotheses. Completing dual-tasks incurred greater cost for manual motor tasks than for verbal fluency tasks. Negative cost of performing dual-tasks diminished as number of languages spoken …

Laterality

Laterality indices (LIs) quantify the left-right asymmetry of brain and behavioural variables and provide a measure that is statistically convenient and seemingly easy to interpret. Substantial variability in how structural and functional asymmetries are recorded, calculated, and reported, however, suggest little agreement on the conditions required for its valid assessment. The present study aimed for consensus on general aspects in this context of laterality research, and more specifically within a particular method or technique (i.e., dichotic listening, visual half-field technique, performance asymmetries, preference bias reports, electrophysiological recording, functional MRI, structural MRI, and functional transcranial Doppler sonography). Experts in laterality research were invited to participate in an online Delphi survey to evaluate consensus and stimulate discussion. In Round 0, 106 experts generated 453 statements …