Giljov Andrey, Malashichev Yegor, Karenina Karina
Department of Vertebrate Zoology, Faculty of Biology, Saint Petersburg State University, Universitetskaya Nab., 7-9, Saint Petersburg, 199034, Russia.
Laboratory of Molecular Neurobiology, Department of Ecological Physiology, Institute of Experimental Medicine, Saint Petersburg, Russia.
Anim Cogn. 2019 Sep;22(5):635-643. doi: 10.1007/s10071-019-01259-0. Epub 2019 Apr 8.
Two brain hemispheres are unequally involved in the processing of social stimuli, as demonstrated in a wide range of vertebrates. A considerable number of studies have shown the right hemisphere advantage for social processing. At the same time, an approach-withdrawal hypothesis, mainly based on experimental evidence, proposes the involvement of both brain hemispheres according to approach and withdrawal motivation. The present study aimed to test the relative roles of the two hemispheres in social responses displayed in a natural context. Visual biases, implicating hemispheric lateralization, were estimated in the social interactions of saiga antelope in the wild. In individually identified males, the left/right visual field use during approach and withdrawal responses was recorded based on the lateral head/body position, relative to the conspecific. Lateralized approach responses were investigated in three types of interactions, with left visual field bias found for chasing a rival, no bias-for attacking a rival, and right visual field bias-for pursuing a female. In two types of withdrawal responses, left visual field bias was found for retreating after fighting, while no bias was evident in fight rejecting. These findings demonstrate that neither the right hemisphere advantage nor the approach-withdrawal distinction can fully explain the patterns of lateralization observed in social behaviour. It is clear that both brain hemispheres play significant roles in social responses, while their relative contribution is likely determined by a complex set of motivational and emotional factors rather than a simple dichotomous distinction such as, for example, approach versus withdrawal motivation.
正如在多种脊椎动物中所表明的那样，两个脑半球在处理社会刺激方面的参与程度并不相同。大量研究表明，右半球在社会处理方面具有优势。与此同时，一种主要基于实验证据的趋近-回避假说提出，根据趋近和回避动机，两个脑半球都会参与其中。本研究旨在测试两个半球在自然情境中显示的社会反应中的相对作用。在野生高鼻羚羊的社会互动中，估计了涉及半球侧化的视觉偏向。在个体识别的雄性中，根据相对于同种个体的头部/身体侧向位置，记录在趋近和回避反应期间对左/右视野的使用情况。在三种类型的互动中研究了侧化的趋近反应，发现追逐对手时存在左视野偏向，攻击对手时无偏向，追求雌性时存在右视野偏向。在两种类型的回避反应中，打斗后撤退时发现左视野偏向，而在拒绝打斗时无明显偏向。这些发现表明，右半球优势和趋近-回避区分都不能完全解释在社会行为中观察到的侧化模式。很明显，两个脑半球在社会反应中都发挥着重要作用，而它们的相对贡献可能由一系列复杂的动机和情感因素决定，而不是由诸如趋近与回避动机这样简单的二分法区分决定。
