Laterality最新文献

One of the trends expected to shape laterality research this decade is closing the gap between human and non-human researchers. A solution to this problem is to view laterality research with a translational lens to leverage knowledge gained in one field to a seemingly disparate field or from one species to another species. The objective of this narrative review was to identify examples of translation in laterality studies that have been conducted in platyrrhine (New World) primates. Our larger goal was to increase rigour and reproducibility for cross-species methodologies in laterality research. As a first step, we surveyed 120 laterality studies conducted in platyrrhine monkeys to describe the research that has been done to date and its impact. In a second step, we conducted a narrative synthesis to identify elements of forward and reverse translation in the reviewed studies on platyrrhine laterality. We described three themes that emerged from our narrative synthesis, and we used these themes to guide our recommendations for future studies in laterality as well as broader health-related research with platyrrhine models.

Over a decade ago, we demonstrated that population-level asymmetries in limb preferences are not uniquely human but occur in various species of non-human animals (Ströckens, F., Güntürkün, O., & Ocklenburg, S. (2013). Limb preferences in non-human vertebrates. Laterality, 18(5), 536-575). While back then, vertebrate limb preference data were too scarce to reconstruct the evolutionary basis of human handedness or apply phylogenetic comparative methods, many voids were filled in the meantime. It is therefore high time to update the last analysis on limb preferences in all non-extinct vertebrate orders in the present article. We show that the robustness of empirical evidence for limb preference in non-human vertebrates increased in the last decade due to (1) more studies, (2) larger sample sizes, and (3) an increased number of meta-analyses integrating findings from various species (e.g., cats, dogs, rats, mice). Similar to the previous publication, we used cladographic comparisons to systematically assess limb preferences in non-extinct vertebrate orders. The identified studies analyzed 172 different species. Overall, 39.53% of species showed evidence for population-level asymmetries, 32.56% showed individual-level asymmetries, and 27.91% showed no asymmetry. These findings not only further support the notion that asymmetries are a widespread feature of vertebrate motor organization, but they also identify crucial gaps that should be filled by future investigations.

This study examined the negative frequency-dependent advantage with a specific focus on half-guard passing in Brazilian jiu-jitsu, a grappling-based martial art that emphasizes ground techniques. We analyzed video footage of Brazilian jiu-jitsu competitions, focusing on half-guard situations, in which guarders (bottom players) entangle one of their opponent's legs while passers (top players) attempt to disentangle the guard to establish dominant control. Both guarders and passers exhibited lateral preferences: guarders were more likely to entangle their opponent's right leg, while passers predominantly passed to their left (i.e., the direction opposite to the entangled leg). Moreover, guard passes initiated to the right were more successful in terms of scoring the point (36.70%) compared to those initiated to the left (19.67%). As the attacks to the less common side (i.e., right) were associated with greater success in Brazilian jiu-jitsu competitions, these findings can be taken as evidence for the negative frequency-dependent advantage of lateralized behaviour in real-world combat scenarios.

The primate order has received considerable interest in studies on lateralized behaviour due to their hemisphere specialization and potentially major implications for the evolution of the human cerebral cortex. The development of the prefrontal and association regions is required for complex behaviours, and there is evidence that some species show hemispheric specialization in the performance of executive functions. However, laterality in relation to working memory in New World monkeys has received little attention. The main aim of this study was to explore the use of the hands and the tail in spider monkeys (Ateles geoffroyi) while performing two visual-spatial delayed match-to-sample (DMTS) tasks. Eight juvenile male spider monkeys raised in outdoor rain forest enclosures were studied. They were tested on two tasks over a period of 20 days. The first DMTS task had a 15-sec delay and used two different containers to hide a reward. The second had a 60-sec delay and used four different containers. Spider monkeys showed a robust and consistent left-hand preference during both acquisition and execution of DMTS tasks, occasionally accompanied by left-side tail use. The left-hand preference provide evidence for lateralized motor control and contribute to understanding hemispheric specialization to working memory in nonhuman primates.

The claim that left handers are over-proportionally common among architects has inspired both scientific theories and popular beliefs about left handedness. However, a review of the existing literature reveals inconsistent findings and a modest overall sample size even when accumulated across studies. The present observational study reinvestigates the notion by assessing the hand preference of acclaimed professional architects. Relevant architects were identified from the winner list of prestigious architecture awards (i.a., The Pritzker prize, The Royal Gold Medal) and by referring to influential architecture magazines. Utilizing pictures and videos available online, hand preference of 515 architects was determined. Of these, 41 cases (8%; confidence limit, CI95%: 5.8-10.5%) were left handed or ambidextrous, a percentage below rather than above the expected 10.6% for the general population (χ² = 3.78, p = .052). To account for known historical trends in left handedness, we selectively considered architects born after 1950. Here, 10.1% (CI95%: 7.0-13.6%) were non-right handed, which was statistically comparable to the expected value (χ² = 0.07, p = .78). In conclusion, the present results allow excluding a relevant over-representation of left and non-right handers among acclaimed architects, challenging the popular belief that left handers (as a group) have a special talent for visual arts and architecture.

The role of each hemisphere of the brain in the perception, production and expression of emotions remains a topic of controversy. Based on asymmetries found through neurological and behavioural studies on both human and non-human animals, several hypotheses and theories have been proposed regarding emotional processing. To contribute to this ongoing discussion and get insights on elephant emotional processing, the present study investigates whether the right hemisphere is more activated during negative emotions in Asian elephants (Elephas maximus). Non-invasive behavioural observations using a video-camera were conducted for 70 h on captive individuals. Using all-occurrences sampling, the side of the body (left or right) to which five self-directed behaviours were oriented was performed on each individual. To investigate the relationship between behavioural laterality and emotional valence, post-conflict behavioural sides were compared to baseline ones in three victims of aggression. Results revealed that, after receiving an aggression, the odds of left side-oriented behaviours significantly increased by 1.82 times when compared to baseline levels. These findings suggest a greater involvement of the right hemisphere in negative emotional processing, aligning with previously proposed theories. Overall, this study may contribute to the understanding of emotional processing in elephants and comparative research on brain asymmetry.

Most research into human cognition has focused predominantly on right-handed individuals, ignoring the left-handed minority due to assumed differences in their brain lateralization. Although practical limitations make it challenging to recruit an equal number of left- and right-handed human participants, research into animal models may shed light on the assumed, but rarely tested, associations between motoric handedness, side preference and brain lateralisation. In the present study, we used the family dog, often studied as a model for complex human-analogue socio-cognitive skills. In Study 1, N = 19 dogs completed a range of behavioural tests assessing lateralisation followed by a sleep EEG recording. In Study 2, N = 14 dogs, specifically selected based on prior side bias history in other cognitive experiments, were behaviourally tested in two side-preference tasks and assessed in a sleep EEG measurement. Results show that both negative and positive correlations exist between certain behavioural lateralisation parameters and hemispheric asymmetry in sleep EEG spectrum. These partly support the use-dependent recovery function of sleep (negative correlations) as well as suggest fingerprint-like individual-level associations between sleep and waking behaviour. These findings are relevant for future research capitalizing on the dog as a model for human visuo-spatial attentional biases.

Readers must be able to make inferences to maintain coherence during reading. Prior research suggests that the cerebral hemispheres process inferences differently depending on level of textual constraint, however, it is not clear when these hemispheric differences occur during reading. The current study investigates how levels of textual constraint influences the hemispheric processing of bridging inferences. Participants read texts promoting a strongly constrained (Experiment 1) or weakly-constrained (Experiment 2) bridging inference and then performed a lexical decision for targets presented to either the left or right hemisphere. Using event-related potential (ERP) analysis, N400 and P600 waveforms were examined during the target presentation. For strongly constrained inferences, a larger N400 effect was found in the right hemisphere than the left hemisphere. For weakly constrained inferences, there was a larger N400 effect overall, but no differences between the hemispheres. In addition, no hemispheric differences were observed for the P600 waveform between the strongly and weakly constrained inferences. Thus, hemispheric asymmetries seem to occur during the early stages of text processing when readers might generate both strongly and weakly-constrained inferences.

The two hemispheres of the brain demonstrate functional asymmetry for global-local processing, with global processing specialised in the right hemisphere and local processing specialised in the left hemisphere. Previous research indicates that hemispheric asymmetry remains intact with age, despite older adults demonstrating worse overall performance for global processing. Participants (127 young, 58 older) completed a hierarchical-figures task using a divided visual field design - stimuli presented briefly to the left or right visual field, such that information was initially processed by the contralateral hemisphere. At the group level: (1) young and older participants demonstrated better performance for global hierarchical figures presented to the left visual field (right-hemisphere global specialisation) and for local hierarchical figures presented to the right visual field (left-hemisphere local specialisation); (2) older participants demonstrated worse overall performance only for global hierarchical figures when compared to young participants. At the individual level, while approximately half the participants demonstrated the predicted pattern of hemispheric asymmetry (right-hemisphere global specialisation; left-hemisphere local specialisation), there were subgroups of participants who demonstrated different patterns. Our findings indicate individual differences in hemispheric asymmetry exist for global-local processing in right-handed participants, and that this may explain the inconsistent findings in group-level studies with small sample sizes.

Familial sinistrality (left-handedness) has been suggested as a proxy for functional language lateralization in the healthy adult brain. Previous studies show that individuals with familial sinistrality tend to have less lateralized language-related brain activation, while individuals without familial sinistrality show greater left-hemispheric lateralization for language. However, familial sinistrality trait has always been treated as a binary categorical variable. In this study a more sensitive quantitative estimate of familial sinistrality (LH load) has been modelled in 39 participants with different direction and degree of handedness by applying a standard genetic multifactorial model. This LH load was tested for an association with functional language lateralization based on an fMRI sentence completion task. Using frequentist and Bayesian statistical frameworks, the association between LH load and language lateralization was not confirmed. The findings of the present research suggest that a quantitative measure of familial sinistrality is not related to individual language representation in the brain measured by a sentence completion fMRI paradigm. However, considering the context of our study and previous research we suggest that familial sinistrality being related to personal handedness could drive functional language lateralization through it.