Survival with an Asymmetrical Brain: Advantages and Disadvantages of Cerebral Lateralization

Total Page:16

File Type:pdf, Size:1020Kb

Survival with an Asymmetrical Brain: Advantages and Disadvantages of Cerebral Lateralization BEHAVIORAL AND BRAIN SCIENCES (2005) 28, 575–633 Printed in the United States of America Survival with an asymmetrical brain: Advantages and disadvantages of cerebral lateralization Giorgio Vallortigara Department of Psychology and B.R.A.I.N. Centre for Neuroscience, University of Trieste, 34123 Trieste, Italy. [email protected] http://psico.univ.trieste.it/labs/acn-lab/ Lesley J. Rogers Centre for Neuroscience and Animal Behaviour, School of Biological, Biomedical and Molecular Sciences, University of New England, Armidale, NSW 2351, Australia. [email protected] http://www.sciences.une.edu.au/zoology/lesleyrogers.asp Abstract: Recent evidence in natural and semi-natural settings has revealed a variety of left-right perceptual asymmetries among ver- tebrates. These include preferential use of the left or right visual hemifield during activities such as searching for food, agonistic re- sponses, or escape from predators in animals as different as fish, amphibians, reptiles, birds, and mammals. There are obvious disad- vantages in showing such directional asymmetries because relevant stimuli may be located to the animal’s left or right at rando m; there is no a priori association between the meaning of a stimulus (e.g., its being a predator or a food item) and its being located to the ani- mal’s left or right. Moreover, other organisms (e.g., predators) could exploit the predictability of behavior that arises from population- level lateral biases. It might be argued that lateralization of function enhances cognitive capacity and efficiency of the brain, thus coun- teracting the ecological disadvantages of lateral biases in behavior. However, such an increase in brain efficiency could be obtained by each individual being lateralized without any need to align the direction of the asymmetry in the majority of the individuals of the pop- ulation. Here we argue that the alignment of the direction of behavioral asymmetries at the population level arises as an “evolutionarily stable strategy” under “social” pressures occurring when individually asymmetrical organisms must coordinate their behavior with the behavior of other asymmetrical organisms of the same or different species. Keywords: asymmetry; brain evolution; brain lateralization; development; evolution of lateralization; evolutionarily stable strategy; hemispheric specialization; laterality; lateralization of behavior; social behavior; theory of games 1. The rise of a neuroethology of the dual brain havior in the natural environment of a variety of species. Though this has gone largely unnoticed among neuropsy- Research on the topic of cerebral lateralization has been chologists who study humans, we believe that such evidence characterized by periodic peaks and troughs in level of in- is going to force all of us to rethink some of the basic issues terest. For instance, the early wave of excitement raised by on the evolution of cerebral lateralization; most important, Broca’s discoveries in the 1860s waned after the turn of the it can also provide a bridge between the (once-believed) century. Similarly, the renaissance of interest induced by disparate disciplines of neuropsychology and evolutionary Sperry’s discoveries with split-brain patients in the 1960s biology, as well as between neuropsychology and develop- has shown signs of decline in recent years (Efron 1990). It mental biology. should be noted that, until very recently, virtually all re- Before considering why we should care about lateral bi- search on cerebral lateralization had been confined to the ases exhibited in naturalistic settings, let us describe some laboratories of experimental psychologists and neuropsy- examples. Consider first the response to predators. A vari- chologists and was largely centered on the human species. ety of species of different classes (see Vallortigara et al. 1999 Even after the evidence for the existence of cerebral later- and Rogers 2002b, for extensive reviews) appear to be more alization in nonhuman species had become impressive, ex- reactive to predators seen in their left, rather than right, tending from fish to primates (for recent reviews see Rogers hemifield. Toads, for instance, are more likely to react, most 2002a; 2002b; 2002c; Rogers & Andrew 2002; Vallortigara often by jumping away, when a simulated predator is intro- 2000; Vallortigara et al. 1999), the subject remained largely duced into their left monocular field than when it is intro- outside the realm of biology on account of a focus on the duced into their right monocular field (Lippolis et al. 2002), causal mechanisms rather than on its function. In the past and recently the same result has been obtained in dunnarts, few years, however, something really new has appeared: Sminthopsis macroura (Lippolis et al. 2005) and chicks namely, evidence for lateral biases affecting everyday be- (Lippolis & Rogers, in preparation). These findings suggest © 2005 Cambridge University Press 0140-525X/05 $12.50 575 Vallortigara & Rogers: Survival with an asymmetrical brain that predator-escape and associated fear responses are con- In contrast to their leftward responses to predators, toads trolled by the right side of the brain. Some evidence indi- strike preferentially at prey to their right side (Vallortigara cates that also in rats the right hemisphere controls fear re- et al. 1998). The rightward bias for feeding responses has sponses: lesions of various types, including infarcts, in the also been documented in a variety of species of birds right hemisphere elevate activity in the open field (Robin- (chicks: Andrew et al. 1982; Mench & Andrew 1986; Rogers son 1985), presumably because the fear response of freez- 1997; Vallortigara et al. 1996; pigeons: Güntürkün 1997; ing is suppressed. Robinson and Downhill (1995) have Güntürkün & Kesch 1987; parids and corvids: Clayton & drawn attention to the similarity between these effects of Krebs 1994; zebrafinch: Alonso 1988; quails: Valenti et al. right hemisphere infarct in rats and the heightened anxiety 2003; black-winged stilts: Ventolini et al. 2005) and has that occurs in humans following damage to the right hemi- been traced back to an appearance during evolution as early sphere. Neurochemical changes, apparently associated as teleost fish (Miklosi & Andrew 1999; Miklosi et al. 1998). with long-term alterations of neurotransmission, are also in- These rightward biases for prey catching and foraging re- duced in the right, but not the left, hemisphere by preda- sponses are apparent when the prey or food has to be dis- tor stress, as shown in rats and cats (Adamec et al. 2003). criminated from similar targets: for example, toads show a In some circumstances, an approach towards, rather than right hemifield preference for directing tongue strikes at avoidance of, a potential predator is needed. Some fish prey that has to be recognized precisely and “handled” with leave their school in groups of two or three to approach a care (e.g., crickets) but not for simplified prey models, such predator and examine it more closely. By placing a mirror as a rectangular silhouette moving along its longitudinal axis on the left or right side of a tank, Bisazza et al. (1999) found (Robins & Rogers 2004). Similarly, chicks show the right- that the test fish approached a predator more closely in or- ward bias for pecking at grain (controlled by inputs from the der to inspect it when the mirror was on its left side than right eye) that has to be discriminated against a distracting when the mirror was on its right side. Such a preference for background or uncovered by removing a lid from a bowl a fish to position itself so that the image of a conspecific is (Andrew et al. 2000). These findings indicate that the left on its left side has been reported, even in the absence of hemisphere, which primarily processes input from the right predators, in eight different species of teleosts (Sovrano et eye, controls responses that require considered discrimina- al. 1999; 2001; see also Sovrano 2004). Similarly, the pref- tion between stimuli and manipulation of objects. To some erence for a fish to position itself so that the image of a degree this particular specialization of the left hemisphere predator being inspected is on its right side has been ob- is manifested in hand preferences in primates (discussed served in the absence of other conspecifics in several spe- later). As the left hemisphere controls the right hand, cies of teleosts (De Santi et al. 2000; 2001). Even tadpoles planned use of the right hand for fine manipulation of ob- have been shown to prefer to position themselves so that jects, as in writing by humans, may have arisen from this an- the image of a conspecific is on their left side (Bisazza et al. cient evolutionary specialization. 2002; Dadda et al. 2003). Aggressive responses also seem to be strongly lateralized in intraspecific agonistic settings: toads (Robins & Rogers 2004; Robins et al. 1998; Vallortigara et al. 1998), lizards Giorgio Vallortigara, Professor of Behavioural (Deckel 1995; 1997; Hews & Worthington 2001; Hews et Neuroscience and Animal Cognition at the University al. 2004), chicks (Vallortigara et al. 2001), adult hens of Trieste, Italy, is the author of over 150 scientific pa- (Rogers 1991), and gelada baboons (Casperd & Dunbar pers, most in the area of animal cognition and compar- 1996) direct more aggressive responses to conspecifics on ative neuroscience. He discovered the first evidence of their left side than they do to those on their right side.
Recommended publications
  • Analysis and Identification of Bite Marks in Forensic Casework
    ORIGINAL | http://dx.doi.org/10.4172/1994-8220.1000102 J Psychiatry 2014;17:475-482 Handedness in schizophrenia and schizoaffective disorder in an afrikaner founder population RH Mataboge¹*, M Joubert¹, JC Jordaan², F Reyneke2, JL Roos1 ¹University of Pretoria, Department of Psychiatry, Pretoria, South Africa ²University of Pretoria, Department of Statistics, Pretoria, South Africa Abstract Objective: An association between the Leucine-rich repeat trans membrane neuronal 1 gene (LRRTM1), schizophrenia/ schizoaffective disorder and handedness was recently claimed to be established. This study aimed to test the hypothesis that Afrikaner patients with schizophrenia/schizoaffective disorder are more non-right handed than their non-affected first- degree relatives and that of two separate control groups. The association between handedness, gender and age at onset of illness in the patients group was also determined. Method: Two cross-sectional studies were carried out, which compared the handedness of a group of 100 (30 females and 70 males) Afrikaner patients with schizophrenia/schizoaffective disorder, their non-affected first-degree relatives, and two separate control groups. Handedness was determined by the Edinburg Handedness Inventory (EHI). Results: Patients were found to be more right-handed than expected with only 17 out of 100 being non-right-handed compared to 11 out of 100 non-affected relatives; 36 out of 100 students and 75 out of 500 non- affected Afrikaner participants. The students were significantly more non-right handed than the patient and family groups but no difference in handedness was found when comparing the patients, family members and 500 participant control group. There was no significant difference between age at onset of illness and handedness.
    [Show full text]
  • In Search of the Biological Roots of Typical and Atypical Human Brain Asymmetry
    Accepted Manuscript In search of the biological roots of typical and atypical human brain asymmetry Clyde Francks PII: S1571-0645(19)30099-5 DOI: https://doi.org/10.1016/j.plrev.2019.07.004 Reference: PLREV 1124 To appear in: Physics of Life Reviews Received date: 9 July 2019 Accepted date: 12 July 2019 Please cite this article in press as: Francks C. In search of the biological roots of typical and atypical human brain asymmetry. Phys Life Rev (2019), https://doi.org/10.1016/j.plrev.2019.07.004 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. In search of the biological roots of typical and atypical human brain asymmetry. Comment on “Phenotypes in hemispheric functional segregation? Perspectives and challenges” by Guy Vingerhoets. Clyde Francks1,2 1Language & Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, the Netherlands 2Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands Email address: [email protected] Keywords: Brain asymmetry; brain functions; laterality; human genetics; left-right axis; brain hemispheres. In this comprehensive and insightful review, Vingerhoets [1] discusses the multi-dimensional nature of inter-individual variation in functional brain asymmetry, and its potential relevance to behavioural variation and psychopathology.
    [Show full text]
  • Algid Ma. 33S~3
    3~?<? Algid Ma. 33S~3 DIFFERENTIAL EFFECTS OF BIOFEEDBACK INPUT ON LOWERING FRONTALIS ELECTROMYOGRAPHIC LEVELS IN RIGHT AND LEFT HANDERS DISSERTATION Presented to the Graduate Council of the University of North Texas in Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY By Kenneth N. Walker, B.S., M.Ed, Denton, Texas August, 1990 Walker, Kenneth N. Differential Effects of Biofeedback Input on Lowering Frontalis Electromyographic Levels In Right and Left Handers. Doctor of Philosophy (Health Psychology/Behavioral Medicine), August 1990, 70 pages, 3 tables, 6 figures, references, 73 titles. This investigation was an attempt to replicate and expand previous research which suggested that laterality of electromyographic biofeedback input had a significant effect in lowering frontalis muscle activity. In 1984 Ginn and Harrell conducted a study in which they reported that subjects receiving left ear only audio biofeedback had significantly greater reductions in frontalis muscle activity than those receiving right ear only or both ear feedback. This study was limited to one biofeedback session and subjects were selected based on demonstration of right hand/ear dominance. The purpose of the present study was to determine whether the left ear effect reported by Ginn and Harrell could be replicated. Furthermore, the current investigation sought to extend the previous finding to left handed subjects and explore the stability of the effect, if found, by adding a second biofeedback session. Subjects were 96 students recruited from undergraduate psychology classes. They were screened for handedness by the Edinburgh Handedness Inventory which resulted in identification of 48 right handers and 48 left handers.
    [Show full text]
  • The Hands to Say It
    Issue 91, February 2008 www.proteinspotlight.org The hands to say it Vivienne Baillie Gerritsen When I was a little girl, I thought that my left-handed classmates were special. I envied their difference. And I used to marvel at the way they crouched over their desk, embracing something invisible as they did their best to avoid smudging ink all over their sheet of paper. Left-handedness is special. But so is right-handedness. Humans are not the only animals to make use of their hands – or claws, or paws, or hooves - but they are the only ones who show a marked preference for either the left one, or the right one. If this is so, there must be a reason for it. And not only must there be a reason but it must translate a certain structure of our brain: an asymmetry somewhere. Indeed, our brain is divided into two hemispheres which are dedicated to processing different activities. One side looks after our dreams, while the other is far more down to earth. LRRTM1 is the first protein to have been discovered which seems to be directly involved in this brain asymmetry. Consequently, it influences the handedness of a human-being and, more astonishingly, may also predispose individuals to psychotic troubles such as schizophrenia. don’t have a distinct preference for one hand over the other. The passing of roles from hand to mind expresses a particular brain structure. In turn, the progressive use of speech has continued to mould our brain into a shape peculiar to the human species.
    [Show full text]
  • Psichologijos Žodynas Dictionary of Psychology
    ANGLŲ–LIETUVIŲ KALBŲ PSICHOLOGIJOS ŽODYNAS ENGLISH–LITHUANIAN DICTIONARY OF PSYCHOLOGY VILNIAUS UNIVERSITETAS Albinas Bagdonas Eglė Rimkutė ANGLŲ–LIETUVIŲ KALBŲ PSICHOLOGIJOS ŽODYNAS Apie 17 000 žodžių ENGLISH–LITHUANIAN DICTIONARY OF PSYCHOLOGY About 17 000 words VILNIAUS UNIVERSITETO LEIDYKLA VILNIUS 2013 UDK 159.9(038) Ba-119 Apsvarstė ir rekomendavo išleisti Vilniaus universiteto Filosofijos fakulteto taryba (2013 m. kovo 6 d.; protokolas Nr. 2) RECENZENTAI: prof. Audronė LINIAUSKAITĖ Klaipėdos universitetas doc. Dalia NASVYTIENĖ Lietuvos edukologijos universitetas TERMINOLOGIJOS KONSULTANTĖ dr. Palmira ZEMLEVIČIŪTĖ REDAKCINĖ KOMISIJA: Albinas BAGDONAS Vida JAKUTIENĖ Birutė POCIŪTĖ Gintautas VALICKAS Žodynas parengtas įgyvendinant Europos socialinio fondo remiamą projektą „Pripažįstamos kvalifikacijos neturinčių psichologų tikslinis perkvalifikavimas pagal Vilniaus universiteto bakalauro ir magistro studijų programas – VUPSIS“ (2011 m. rugsėjo 29 d. sutartis Nr. VP1-2.3.- ŠMM-04-V-02-001/Pars-13700-2068). Pirminis žodyno variantas (1999–2010 m.) rengtas Vilniaus universiteto Specialiosios psichologijos laboratorijos lėšomis. ISBN 978-609-459-226-3 © Albinas Bagdonas, 2013 © Eglė Rimkutė, 2013 © VU Specialiosios psichologijos laboratorija, 2013 © Vilniaus universitetas, 2013 PRATARMĖ Sparčiai plėtojantis globalizacijos proce- atvejus, kai jų vertimas į lietuvių kalbą gali sams, informacinėms technologijoms, ne- kelti sunkumų), tik tam tikroms socialinėms išvengiamai didėja ir anglų kalbos, kaip ir etninėms grupėms būdingų žodžių, slengo,
    [Show full text]
  • Hemispheric Brain Asymmetry Differences in Youths with Attention
    NeuroImage: Clinical 18 (2018) 744–752 Contents lists available at ScienceDirect NeuroImage: Clinical journal homepage: www.elsevier.com/locate/ynicl Hemispheric brain asymmetry differences in youths with attention-deficit/ T hyperactivity disorder ⁎ P.K. Douglasa,b, , Boris Gutmanc, Ariana Andersonb, C. Lariosa, Katherine E. Lawrenced, Katherine Narrd, Biswa Senguptae, Gerald Cooraye, David B. Douglasf, Paul M. Thompsonc, James J. McGoughb, Susan Y. Bookheimerb a University of Central Florida, IST, Modeling and Simulation Department, FL, USA b Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, UCLA, CA, USA c Imaging Genetics Center, USC Keck School of Medicine, Marina del Rey, CA, USA d Laboratory of Neuroimaging, UCLA, CA, USA e Wellcome Trust Centre for Neuroimaging, 12 Queen Square, UCL, London, UK f Nuclear Medicine and Molecular Imaging, Stanford University School of Medicine, Palo Alto, CA, USA ABSTRACT Introduction: Attention-deficit hyperactive disorder (ADHD) is the most common neurodevelopmental disorder in children. Diagnosis is currently based on behavioral criteria, but magnetic resonance imaging (MRI) of the brain is increasingly used in ADHD research. To date however, MRI studies have provided mixed results in ADHD patients, particularly with respect to the laterality of findings. Methods: We studied 849 children and adolescents (ages 6–21 y.o.) diagnosed with ADHD (n = 341) and age- matched typically developing (TD) controls with structural brain MRI. We calculated volumetric measures from 34 cortical and 14 non-cortical brain regions per hemisphere, and detailed shape morphometry of subcortical nuclei. Diffusion tensor imaging (DTI) data were collected for a subset of 104 subjects; from these, we calculated mean diffusivity and fractional anisotropy of white matter tracts.
    [Show full text]
  • A Large-Scale Estimate on the Relationship Between Language And
    www.nature.com/scientificreports OPEN A large‑scale estimate on the relationship between language and motor lateralization Julian Packheiser1*, Judith Schmitz2, Larissa Arning3, Christian Beste4, Onur Güntürkün1 & Sebastian Ocklenburg1,5 Human language is dominantly processed in the left cerebral hemisphere in most of the population. While several studies have suggested that there are higher rates of atypical right‑hemispheric language lateralization in left‑/mixed‑handers, an accurate estimate of this association from a large sample is still missing. In this study, we comprised data from 1,554 individuals sampled in three previous studies in which language lateralization measured via dichotic listening, handedness and footedness were assessed. Overall, we found a right ear advantage indicating typical left‑hemispheric language lateralization in 82.1% of the participants. While we found signifcantly more left‑handed individuals with atypical language lateralization on the categorical level, we only detected a very weak positive correlation between dichotic listening lateralization quotients (LQs) and handedness LQs using continuous measures. Here, only 0.4% of the variance in language lateralization were explained by handedness. We complemented these analyses with Bayesian statistics and found no evidence in favor of the hypothesis that language lateralization and handedness are related. Footedness LQs were not correlated with dichotic listening LQs, but individuals with atypical language lateralization also exhibited higher rates of atypical footedness on the categorical level. We also found diferences in the extent of language lateralization between males and females with males exhibiting higher dichotic listening LQs indicating more left‑hemispheric language processing. Overall, these fndings indicate that the direct associations between language lateralization and motor asymmetries are much weaker than previously assumed with Bayesian correlation analyses even suggesting that they do not exist at all.
    [Show full text]
  • A Cinch for the Brain
    A Cinch for the Brain Our bodies, our behavior and even our brains are anything but symmetrical. And this seems to be an important factor in the seamless functioning of our thought, speech and motor faculties. Researchers at the Max Planck Institute for Psycholinguistics in Nijmegen are currently searching for genetic clues to this phenomenon. They want to decode the fundamental molecular biological mechanisms that contribute to asymmetry in the brain, and to identify possible causes for neurological disorders. TEXT STEFANIE REINBERGER t first glance, the human ture. It’s divided into two halves, both A strong left: Rafael Nadal, for body appears to be com- of which are equal in size and whose many years the world’s number pletely symmetrical: two furrows and bulges follow a similar pat- one men’s tennis player, is right-handed but holds the arms, two legs, two eyes, tern. But the functional centers are ex- racket in his left hand most of two ears. Even features tremely unevenly distributed. The right the time. Researchers are likeA the nose and mouth appear to be and left hemispheres specialize in dif- studying how the brains of left- evenly positioned in both halves of ferent cognitive functions. They essen- and right-handed people differ. the face in most people. On closer in- tially divide up the work between them, spection, though, we see that one leg possibly to expand the total range of is longer than the other, one hand is tasks performed. stronger, or maybe the left ear is posi- “Lateralization is a very distinct phe- tioned lower than the right one.
    [Show full text]
  • Handedness and White Matter Networks
    NROXXX10.1177/1073858420937657The NeuroscientistBudisavljevic et al. 937657review-article2020 Review The Neuroscientist 2021, Vol. 27(1) 88 –103 Handedness and White Matter Networks © The Author(s) 2020 Article reuse guidelines: sagepub.com/journals-permissions DOI:https://doi.org/10.1177/1073858420937657 10.1177/1073858420937657 journals.sagepub.com/home/nro Sanja Budisavljevic1,2, Umberto Castiello1 , and Chiara Begliomini1 Abstract The development and persistence of laterality is a key feature of human motor behavior, with the asymmetry of hand use being the most prominent. The idea that asymmetrical functions of the hands reflect asymmetries in terms of structural and functional brain organization has been tested many times. However, despite advances in laterality research and increased understanding of this population-level bias, the neural basis of handedness remains elusive. Recent developments in diffusion magnetic resonance imaging enabled the exploration of lateralized motor behavior also in terms of white matter and connectional neuroanatomy. Despite incomplete and partly inconsistent evidence, structural connectivity of both intrahemispheric and interhemispheric white matter seems to differ between left and right-handers. Handedness was related to asymmetry of intrahemispheric pathways important for visuomotor and visuospatial processing (superior longitudinal fasciculus), but not to projection tracts supporting motor execution (corticospinal tract). Moreover, the interindividual variability of the main commissural pathway corpus callosum seems to be associated with handedness. The review highlights the importance of exploring new avenues for the study of handedness and presents the latest state of knowledge that can be used to guide future neuroscientific and genetic research. Keywords handedness, white matter, diffusion imaging, tractography, corpus callosum, corticospinal tract, superior longitudinal fasciculus Introduction dominant for hand control.
    [Show full text]
  • Left -Handedness Laterality Characteristics and Their
    LEFT -HANDEDNESS LATERALITY CHARACTERISTICS AND THEIR EDUCATIONAL IMPLICATIONS by Margaret MacDonald Clark, M.A., Ed.B. Submitted in fulfilment of the requirements for the degree Doctor of Philosophy University of Glasgow 1953 ProQuest Number: 13838552 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a com plete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest ProQuest 13838552 Published by ProQuest LLC(2019). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States C ode Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106- 1346 ii PREFACE Lack of knowledge concerning left-handedness springs from the multiplicity of studies and contradictory nature of the findings on the various aspects of laterality, father than any insufficiency of material on the subject. The absence of any single authoritative work and extensiveness of existing material make necessary for a full appreciation of the problem a study more prolonged than the average interested person is willing or able to make. The present work, presenting as it does both an attempt at critical evaluation of previous investigations and an original study of laterality characteristics in a group of normal children, will it is hoped satisfy a need for a comprehensive report on the subject. The practical problems confronting teachers and parents dealing with left-handed children have been kept in the forefront through­ out, in the hope that the information contained herein may make some contribution towards a better understanding of left-handedness and may even lead to a more tolerant attitude towards the * sinister minority*, to which the author herself belongs.
    [Show full text]
  • Subtle Left-Right Asymmetry of Gene Expression Profiles in Embryonic
    bioRxiv preprint doi: https://doi.org/10.1101/263111; this version posted February 9, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 1 Subtle left-right asymmetry of gene 2 expression profiles in embryonic and 3 foetal human brains 4 5 Carolien G.F. de Kovel1, Steven N. Lisgo2, Simon E. Fisher1,3, Clyde Francks1,3* 6 7 1 Language and Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The 8 Netherlands 9 2 Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom 10 3 Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands 11 12 13 Contact information: 14 Clyde Francks 15 Dept Language & Genetics, Max Planck Institute for Psycholinguistics 16 P.O. Box 310 17 6500 AH Nijmegen 18 The Netherlands 19 E: [email protected] 20 T: +31 24 3521929 21 22 23 1 bioRxiv preprint doi: https://doi.org/10.1101/263111; this version posted February 9, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 24 Abstract 25 Left-right laterality is an important aspect of human brain organization for which the genetic basis is 26 poorly understood. Using RNA sequencing data we contrasted gene expression in left- and right-sided 27 samples from several structures of the anterior central nervous systems of post mortem human 28 embryos and fetuses.
    [Show full text]
  • Laterality and Performance in Combat Sports
    REVIEW ARTICLE Laterality and performance in combat sports 1ABCD 1ABCD 2BD Authors’ Contribution: Xurxo Dopico-Calvo , Eliseo Iglesias-Soler , Luis Morenilla , A Study Design Manuel A Giráldez1BD, Luis Santos3BD, Antonio Ardá4BD B Data Collection C Statistical Analysis 1 Performance and Health Group (PH-G), Departamento de Educación Física e Deportiva, Facultade de Ciencias do D Manuscript Preparation Deporte e a Educación Física, Universidade da Coruña, A Coruña, Spain E Funds Collection 2 Grupo de aprendizaxe e control do movemento humano en actividade física e deporte (ACoM), Departamento de Educación Física e Deportiva, Facultade de Ciencias do Deporte e a Educación Física, Universidade da Coruña, A Coruña, Spain 3 University School of Sports Medicine, University of Oviedo, Spain 4 Unidade de Análise e avaliación das capacidade motrices e conductuais no deporte. Departamento de Educación Física e Deportiva, Facultade de Ciencias do Deporte e a Educación Física, Universidade da Coruña, A Coruña, Spain Received: 29 October 2016; Accepted: 25 April 2016; Published online: 30 June 2016 AoBID: 11230 Abstract Literature has shown a relationship between laterality and an over-representation of left-handed athletes in certain sports, and especially in sports one against one, such as judo, tennis, boxing or fencing; the main ex- planation has been attributed to greater chance of success. Some authors have explained it through a genetic or innate superiority hypothesis, however others defend the strategic advantage hypothesis. The study aim is an overview about laterality, sporting success, over-representation of left-dominant athletes executing techniques, and the possibility of modulating that over-representation through training and based on negative frequency-dependent selection hypothesis, given that in sports such as fencing, boxing or judo, tacti- cal designs and training actions have been developed based on the opponent’s predominant side while execut- ing skills.
    [Show full text]