Laterality最新文献

{"title":"No evidence for lateralized bias or preference in the sleeping positions of domestic cats.","authors":"Andrew S Cooke","doi":"10.1080/1357650X.2026.2633997","DOIUrl":"10.1080/1357650X.2026.2633997","url":null,"abstract":"<p><p>Lateralization has been observed across the animal kingdom. In mammals, this is often associated with complex or precise motor tasks, such as paw and hand use. A recent study reported that cats prefer a leftward (clockwise) sleeping position, suggestive of lateralization. However, limitations in the design and execution of that work raise questions about this finding. The aim of the present study was to further investigate this effect and establish if there is a lateralized preference in the sleeping position of domestic cats. Three activities were performed (1) assessment of YouTube videos of unique cats' sleeping positions; (2) assessment of images from Reddit of unique cats' sleeping positions and (3) assessment of images from Instagram to quantify the leftwards: rightwards preference of specific cats. Compared to a 50:50 ratio, no significant difference was found in lying position from videos (<i>χ</i>² = 0.074, <i>p</i> = 0.786), images of unique cats (<i>χ</i>² = 0.522, <i>p</i> = 0.470) or from cats with multiple images (<i>t</i> = 0.836, <i>p</i> = 0.407). Given the full range of evidence available, it cannot be concluded that there is any population bias, preference or lateralization in the sleeping position of domestic cats. Results to the contrary can be explained by methodological issues.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"306-323"},"PeriodicalIF":1.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Speech and motor laterality reassessed: a functional transcranial Doppler follow-up to the online verbal visual half-field task.","authors":"Jack Harry Grant, John M Hudson, Jessica C Hodgson","doi":"10.1080/1357650X.2026.2636585","DOIUrl":"10.1080/1357650X.2026.2636585","url":null,"abstract":"<p><p>Reliable measures of language laterality are essential for understanding relationships between speech and other lateralized functions. In a previous study (Grant et al., 2023. Testing the relationship between lateralization on sequence-based motor tasks and language laterality using an online battery. <i>Laterality</i>, 28(1), 1-31), an online verbal visual half-field (vVHF) task assessed speech production laterality but showed limited reliability and validity. The present study conducted novel analyses linking this measure with functional transcranial Doppler ultrasound (fTCD) data collected from the same sample as part of a separate project (Parker et al., 2022. Inconsistent language lateralisation: Testing the dissociable language laterality hypothesis using behaviour and lateralised cerebral blood flow. <i>Cortex</i>, 154, 105-134). In total, 187 participants completed both the online battery and an in-person fTCD sentence-generation task. Results confirmed robust left lateralization for speech production across handedness groups. However, laterality indices from the vVHF task did not correlate with the fTCD measure, reinforcing concerns about the validity of the online paradigm. Replicating previous findings, no significant association was observed between categorical measures of speech and motor laterality. Exploratory analyses revealed a significant positive correlation between motor laterality indices and fTCD speech laterality.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"390-407"},"PeriodicalIF":1.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147373374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dissecting pseudoneglect in real and virtual environments: effects of tool and stimulus, not distance or environment.","authors":"Dalya Moultaka, Tifanie Bouchara, Alma Guilbert","doi":"10.1080/1357650X.2026.2622714","DOIUrl":"10.1080/1357650X.2026.2622714","url":null,"abstract":"<p><p>Pseudoneglect is a spatial bias favoring the left side of space observed in healthy individuals, typically shown by a leftward deviation when bisecting horizontal lines. Although environmental and individual factors are known to modulate this bias, findings remain inconsistent. This study aimed to provide new insights into the influence of four environmental factors on pseudoneglect: Distance (near, far), Environment (real, immersive Virtual Reality (iVR)), Tool (pen, laser pointer), Stimulus (line, object), while controlling handedness. Fifty-five participants (<i>M</i> = 20.6 years, <i>SD</i> = 2.3, 35 right-handed) completed three line bisection tasks in a real environment (paper-and-pencil at near distance, laser at near and far distances) and three in iVR: (laser at near and far distances, French baguette bisection at near distance). A significant Tool effect emerged: pseudoneglect appeared only in the paper-and-pencil bisection task, while a rightward bias observed with a laser pointer. Stimulus also had a significant effect, with a more rightward bias for the baguette than for lines. No main effects of Distance, Environment, or Handedness were found. Several interpretations are discussed, such as inter-individual variability, coding of peripersonal and extrapersonal spaces, and interaction between semantic and attentional networks. Our results emphasize the need to homogenize methodologies across studies.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"275-305"},"PeriodicalIF":1.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146151008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coiling chirality? Wild eastern diamondback rattlesnakes (<i>Crotalus adamanteus</i>) do not exhibit clear lateralized coiling behaviour.","authors":"Ella Guedouar, Adrian Rodriguez, Mark J Margres, Charles Gunnels Iv, Matthew F Metcalf","doi":"10.1080/1357650X.2026.2637745","DOIUrl":"10.1080/1357650X.2026.2637745","url":null,"abstract":"<p><p>Behavioural lateralization has been recorded in various groups, from lower vertebrates to humans. Handedness, or the preferred use of one hand over the other, as observed in humans, is thought to be related to brain structure and function. Snakes have been recorded to potentially display such sided behaviours. The asymmetrical internal anatomy of snakes may provide a basis for coiling handedness in the form of clockwise versus anti-clockwise coiling to protect vital organs or provide an advantageous strike to capture prey. The few studies on behavioural lateralization in snakes have documented inconsistent evidence to accurately determine whether coiling direction biases exist. However, these studies either failed to include repeated individuals or were conducted in aseptic environments, producing results that may not reflect natural conditions. To determine whether coil position bias exists amongst wild individuals, we studied eastern diamondback rattlesnakes (<i>Crotalus adamanteus</i>) at two sampling sites. We found no clear bias for coiling direction across populations or individuals, though sex-biased differences in directionality were identified. We found that lateralized coiling is not found in all snakes, and the genetic and ecological significance of such polymorphism, if any, warrants further investigation.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"324-338"},"PeriodicalIF":1.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147366917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The modified fighting hypothesis of handedness: Evidence from sharp force injuries and further considerations.","authors":"Paul Rodway, Matz Lennart Larsson, Astrid Schepman","doi":"10.1080/1357650X.2026.2638523","DOIUrl":"10.1080/1357650X.2026.2638523","url":null,"abstract":"<p><p>The modified fighting hypothesis (MFH) proposes that most humans are right-handed because it conveyed an advantage during intraspecific fights with sharp weapons, due to the leftward location of the heart and aorta. An examination of the literature on sharp force injury showed that the thoracic region is penetrated more than any other region, and the left thorax is penetrated approximately 2.4 times more often than the right thorax. Handedness influenced the side of the thorax targeted, with most right-handers penetrating the left thorax in front of their right hand. As two thirds of the heart is in the left thorax, right-handers appear more likely to injure the heart and other vital structures, increasing their lethality when using a sharp weapon. This difference in lethality may have resulted in a survival advantage for right-handers. We discuss the possibility that increased use of sharp weapons in hominins caused evolutionary changes in anatomical traits, reducing sexual dimorphism and increasing population-level right lateralization. Similarities in lateralized fighting in humans and non-human species are considered and related to the MFH.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"339-389"},"PeriodicalIF":1.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147357010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of the left-handedness stigmatization scale for the Middle East and North Africa region (LHSS-MENA): expert validity ratio, exploratory factor and confirmatory factor analyses.","authors":"Gabriel Andrade, Enas Mohamed, Dalia Bedewy","doi":"10.1080/1357650X.2026.2645941","DOIUrl":"https://doi.org/10.1080/1357650X.2026.2645941","url":null,"abstract":"<p><p><i>Background:</i> Hand preference is influenced by genetic, anatomical, and environmental factors, leading to societal biases that stigmatize left-handed individuals, especially in Arab and Muslim cultures. These biases create pressures for conformity and feelings of inadequacy among left-handed individuals, highlighting the need for a scale to measure this stigmatization in the MENA region. <i>Methods:</i> A set of 54 items assessing left-handedness stigmatization was evaluated by seven experts, resulting in 24 items. An Exploratory Factor Analysis (EFA) with 266 participants identified 17 items clustering into three factors: \"Stereotypes against left-handedness,\" \"Right-handed normative pressure,\" and \"Left-handed acceptance.\" Confirmatory Factor Analysis (CFA) was conducted with 423 participants. <i>Results:</i> The scale demonstrated good reliability (Cronbach's alpha = 0.78). The EFA and CFA provided good fits (RMSEA = 0.04, <i>p</i> = 0.002 and RMSEA = 0.0638, <i>p</i> < 0.001, respectively). <i>Conclusion:</i> The Left-Handed Stigmatization Scale for MENA (LHSS-MENA) is a good tool for assessing societal attitudes toward left-handed individuals, effectively capturing the nuances of stigma and societal pressures with reliable psychometric properties. KEYWORDS: Stigma; MENA region; Left-handedness; Scale; Factor Analyses.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"1-31"},"PeriodicalIF":1.5,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147515667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Princess hands: Handedness of protagonists versus antagonists in Disney's \"Princess\" animated movies.","authors":"Ruth E Propper, Alexis Narine, Suha Aman, Stephen D Christman","doi":"10.1080/1357650X.2026.2646485","DOIUrl":"https://doi.org/10.1080/1357650X.2026.2646485","url":null,"abstract":"<p><p>An analysis of hand use by character role (protagonist princesses versus antagonist villains) from all 13 Disney \"Princess\" movies was conducted. Over time, protagonists became less right-handed than antagonists, with this relationship primarily occurring after 1992. Overall, protagonists became less right-handed over the past ∼80 years, while antagonists' handedness remained stable. Hand use in characters was much less right-handed than in the human population and, contrary to the cultural and historical association between left-handedness and evil, antagonists now tend to be more strongly right-handed than protagonists.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"1-10"},"PeriodicalIF":1.5,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147515764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Top-down modulation of hemispheric differences and spatial attention effects for verbal and non-verbal stimuli.","authors":"Grace Wang, Jed A Meltzer","doi":"10.1080/1357650X.2026.2644266","DOIUrl":"https://doi.org/10.1080/1357650X.2026.2644266","url":null,"abstract":"<p><p>The human brain exhibits lateralization, with language preferentially processed in the left hemisphere, and facial recognition and spatial attention stronger in the right. The balance of hemispheric engagement is also influenced by directed spatial attention, but interactions between these factors are poorly understood. Our studies investigated the role of directed spatial attention and stimulus meaningfulness at modulating hemispheric biases in the recognition of words and faces. Four online studies employed a divided visual field paradigm and a modified \"Posner task\" to direct spatial attention in two tasks: lexical decision and face detection. Our findings revealed expected hemispheric dominance and performance enhancement with valid spatial cueing. Attentional cueing effects were more salient for meaningful stimuli (words, upright faces) but strongly attenuated for pseudowords and inverted faces. Similarly, hemispheric lateralization effects varied with stimulus type: the left-hemisphere advantage was stronger for valid word stimuli, both with (Expt.1) and without spatial cueing (Expt.3), while right-hemisphere advantage for faces trended larger for upright faces without spatial cueing (Expt.4). These findings indicate that both hemispheric lateralization and spatial cueing involve a top-down process, enhancing stimulus recognition through specialization and directed attention, providing insights into the mechanisms supporting lateralized perceptual performance in healthy adults.<b>Public Significance Statement</b>We show that the brain's ability to recognize words and faces is driven by a top-down process that involves directing our attention to enhance recognition, such that attention benefits recognition of real words and faces, but not rejection of made-up words and inverted faces. Likewise, the brain's hemispheric advantages (left hemisphere specialized for words, right hemisphere for faces) are larger for recognition of real stimuli vs. rejection of false ones. These findings clarify that hemispheric advantages, whether innate (e.g., left hemisphere language superiority) or \"on-the-fly\" (directing attention to one side of space) apply mainly to real recognizable stimuli, and therefore involve a top-down processing mechanism.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"1-45"},"PeriodicalIF":1.5,"publicationDate":"2026-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147494278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A minimal dynamical model linking early embryonic asymmetry to hemispheric lateralization.","authors":"Nobuchika Yamaki, Tenna Churiki","doi":"10.1080/1357650X.2026.2646484","DOIUrl":"https://doi.org/10.1080/1357650X.2026.2646484","url":null,"abstract":"<p><p>Hemispheric asymmetry is a defining feature of the human brain, yet how weak early left-right biases develop into stable hemispheric specialization remains unclear. Although molecular mechanisms establish initial embryonic asymmetries, a mechanistic explanation linking these early biases to persistent hemispheric differences has been lacking. Here we introduce a minimal dynamical model that isolates the developmental conditions under which small left-right asymmetries can be amplified and stabilized. Each hemisphere is represented by a continuous maturation variable, with reciprocal interhemispheric interactions modelled as nonlinear inhibitory coupling. Analytical stability analysis shows that hemispheric differentiation emerges when the symmetric equilibrium becomes unstable, allowing asymmetry to arise as a dynamical outcome of coupled development rather than explicit hemisphere-specific programming. Numerical simulations demonstrate that stable hemispheric asymmetry robustly emerges once interhemispheric coupling exceeds a critical threshold. Without intrinsic bias (ϵ = 0), symmetry breaking occurs through stochastic amplification, producing left- and right-dominant outcomes with approximately equal probability. Introducing a weak intrinsic bias does not create asymmetry but biases the selection among available asymmetric states. These results provide a minimal dynamical bridge linking early embryonic asymmetry to later hemispheric specialization.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"1-14"},"PeriodicalIF":1.5,"publicationDate":"2026-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147491932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laterality of face orientation in traditional Japanese portraits.","authors":"Hikari Yamashita","doi":"10.1080/1357650X.2026.2639599","DOIUrl":"https://doi.org/10.1080/1357650X.2026.2639599","url":null,"abstract":"<p><p>The left face (cheek) bias, predominantly associated with female sitters, is prevalent in Western portraits and photographs. This bias toward the left cheek can be explained by the idea that the left side of the face is more expressive than the right, based on its association with emotional processing in the right hemisphere. We investigated whether left-face bias is also observed in Japanese portrait paintings, which have different cultural backgrounds and styles. We studied 614 portraits of 112 women and 502 men from the Heian to Meiji period (roughly corresponding to the 9th to 19th centuries). Of them, only five were frontal portraits (all were of male monks). Of the remaining 609 (depicting 112 women and 497 men), 349 were left-faced (57.3%), indicating a significant left-face bias. Furthermore, 61.6% of female portraits compared to 56.3% of male portraits were left faced. Analysis of male portraits by vocation showed a significant left-face bias for \"samurai\" and \"painters and literati,\" while a right-face bias for \"monks.\" These results are discussed from the perspectives of neuropsychology and cultural studies.</p>","PeriodicalId":47387,"journal":{"name":"Laterality","volume":" ","pages":"1-13"},"PeriodicalIF":1.5,"publicationDate":"2026-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147365785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}