Berretz Gesa, Wolf Oliver T, Güntürkün Onur, Ocklenburg Sebastian
Department of Biopsychology, Institute of Cognitive Neuroscience, Ruhr-University Bochum, Bochum, Germany.
Department of Cognitive Psychology, Institute of Cognitive Neuroscience, Ruhr-University Bochum, Bochum, Germany.
Cortex. 2020 Apr;125:215-232. doi: 10.1016/j.cortex.2019.12.019. Epub 2020 Jan 16.
Hemispheric asymmetries are a major organizational principle of the human brain. In different neurodevelopmental and psychiatric disorders, like schizophrenia, autism spectrum disorders, depression, dyslexia and posttraumatic stress disorder, functional and/or structural hemispheric asymmetries are altered compared to healthy controls. The question, why these disorders all share the common characteristic of altered hemispheric asymmetries despite vastly different etiologies and symptoms remains one of the unsolved mysteries of laterality research. This review is aimed at reviewing potential reasons for why atypical lateralization is so common in many neurodevelopmental and psychiatric disorders. To this end, we review the evidence for overlaps in the genetic and non-genetic factors involved in the ontogenesis of different disorders and hemispheric asymmetries. While there is evidence for genetic overlap between different disorders, only few asymmetry-related loci have also been linked to disorders and importantly, those effects are mostly specific to single disorders. However, there is evidence for shared non-genetic influences between disorders and hemispheric asymmetries. Most neurodevelopmental and psychiatric disorders show alterations in the hypothalamic-pituitary adrenocortical (HPA) axis and maternal as well as early life stress have been implicated in their etiology. Stress has also been suggested to affect hemispheric asymmetries. We propose a model in which early life stress as well as chronic stress not only increases the risk for psychiatric and neurodevelopmental disorders but also changes structural and functional hemispheric asymmetries leading to the aberrant lateralization patterns seen in these disorders. Thus, pathology-related changes in hemispheric asymmetries are not a factor causing disorders, but rather a different phenotype that is affected by partly overlapping ontogenetic factors, primarily stress.
半球不对称是人类大脑的一个主要组织原则。在不同的神经发育和精神疾病中，如精神分裂症、自闭症谱系障碍、抑郁症、诵读困难和创伤后应激障碍，与健康对照相比，功能和/或结构上的半球不对称会发生改变。尽管病因和症状差异巨大，但这些疾病为何都具有半球不对称改变这一共同特征，仍是横向研究中未解之谜之一。本综述旨在探讨为何非典型的大脑偏侧化在许多神经发育和精神疾病中如此常见的潜在原因。为此，我们回顾了不同疾病的个体发生过程以及半球不对称所涉及的遗传和非遗传因素重叠的证据。虽然有证据表明不同疾病之间存在遗传重叠，但只有少数与不对称相关的基因座也与疾病有关，重要的是，这些影响大多只针对单一疾病。然而，有证据表明疾病和半球不对称之间存在共同的非遗传影响。大多数神经发育和精神疾病都表现出下丘脑 - 垂体 - 肾上腺皮质（HPA）轴的改变，母体以及早期生活压力也被认为与它们的病因有关。也有人提出压力会影响半球不对称。我们提出一个模型，其中早期生活压力以及慢性压力不仅会增加患精神和神经发育疾病的风险，还会改变结构和功能上的半球不对称，导致在这些疾病中出现异常的大脑偏侧化模式。因此，与病理相关的半球不对称变化不是导致疾病的因素，而是一种不同的表型，它受到部分重叠的个体发生因素（主要是压力）的影响。
