Abstract:
Schizophrenia (SCZ) and bipolar disorder (BD) are severe psychiatric disorders that share clinical features and several risk genes. Important information about their genetic underpinnings arises from intermediate phenotypes (IPs), quantifiable biological traits that are more prevalent in unaffected relatives (RELs) of patients compared to the general population and co-segregate with the disorders. Within IPs, neuropsychological functions and neuroimaging measures have the potential to provide useful insight into the pathophysiology of SCZ and BD. In this context, the present narrative review provides a comprehensive overview of the available evidence on deficits in neuropsychological functions and neuroimaging alterations in unaffected relatives of SCZ (SCZ-RELs) and BD (BD-RELs). Overall, deficits in cognitive functions including intelligence, memory, attention, executive functions, and social cognition could be considered IPs for SCZ. Although the picture for cognitive alterations in BD-RELs is less defined, BD-RELs seem to present worse performances compared to controls in executive functioning, including adaptable thinking, planning, self-monitoring, self-control, and working memory. Among neuroimaging markers, SCZ-RELs appear to be characterized by structural and functional alterations in the cortico-striatal-thalamic network, while BD risk seems to be associated with abnormalities in the prefrontal, temporal, thalamic, and limbic regions. In conclusion, SCZ-RELs and BD-RELs present a pattern of cognitive and neuroimaging alterations that lie between patients and healthy individuals. Similar abnormalities in SCZ-RELs and BD-RELs may be the phenotypic expression of the shared genetic mechanisms underlying both disorders, while the specificities in neuropsychological and neuroimaging profiles may be associated with the differential symptom expression in the two disorders.
摘要:
精神分裂症(SCZ)和双相情感障碍(BD)是严重的精神疾病,具有共同的临床特征和几种风险基因。有关其遗传基础的重要信息来自中间表型(IP),与普通人群相比,在未受影响的患者亲属(REL)中更为普遍,并且与疾病共同隔离。在IP中,神经心理学功能和神经影像学检查有可能为SCZ和BD的病理生理学提供有用的见解。在这种情况下,本叙述性综述全面概述了SCZ(SCZ-RELs)和BD(BD-RELs)未受影响亲属的神经心理功能缺陷和神经影像学改变的现有证据.总的来说,包括智力在内的认知功能缺陷,记忆,注意,执行功能,社会认知可以被认为是SCZ的IP。虽然BD-REL中认知改变的情况不太明确,与执行功能的控制相比,BD-RELs似乎表现更差,包括适应性思维,规划,自我监控,自我控制,和工作记忆。在神经成像标记中,SCZ-RELs的特征似乎在于皮质-纹状体-丘脑网络的结构和功能改变,虽然BD风险似乎与前额叶异常有关,temporal,丘脑,和边缘区域。总之,SCZ-RELs和BD-RELs呈现了患者和健康个体之间的认知和神经影像学改变的模式。SCZ-RELs和BD-RELs的类似异常可能是两种疾病共同遗传机制的表型表达,而神经心理学和神经影像学的特异性可能与两种疾病的差异症状表达有关。