Abstract:
Impaired social cognition is a core deficit in frontotemporal dementia (FTD). It is most commonly associated with the behavioural-variant of FTD, with atrophy of the orbitofrontal and ventromedial prefrontal cortex. Social cognitive changes are also common in semantic dementia, with atrophy centred on the anterior temporal lobes. The impairment of social behaviour in FTD has typically been attributed to damage to the orbitofrontal cortex and/or temporal poles and/or the uncinate fasciculus that connects them. However, the relative contributions of each region are unresolved. In this review, we present a unified neurocognitive model of controlled social behaviour that not only explains the observed impairment of social behaviours in FTD, but also assimilates both consistent and potentially contradictory findings from other patient groups, comparative neurology and normative cognitive neuroscience. We propose that impaired social behaviour results from damage to two cognitively- and anatomically-distinct components. The first component is social-semantic knowledge, a part of the general semantic-conceptual system supported by the anterior temporal lobes bilaterally. The second component is social control, supported by the orbitofrontal cortex, medial frontal cortex and ventrolateral frontal cortex, which interacts with social-semantic knowledge to guide and shape social behaviour.
摘要:
社会认知受损是额颞叶痴呆(FTD)的核心缺陷。它通常与FTD的行为变体有关,眶额叶和腹内侧前额叶皮质萎缩。社会认知变化在语义痴呆中也很常见,萎缩集中在前颞叶。FTD中社交行为的损害通常归因于眶额皮质和/或颞叶和/或连接它们的钩束束的损害。然而,每个地区的相对贡献尚未解决。在这篇评论中,我们提出了一个控制社会行为的统一神经认知模型,不仅解释了在FTD中观察到的社会行为损害,但也吸收了其他患者群体的一致和潜在矛盾的发现,比较神经学和规范认知神经科学。我们认为,受损的社会行为是由于对两个认知和解剖学上不同的组成部分的损害所致。第一个组成部分是社会语义知识,一般语义概念系统的一部分,由双侧颞叶支持。第二部分是社会控制,由眶额皮质支持,内侧额叶皮质和腹外侧额叶皮质,它与社会语义知识相互作用,以指导和塑造社会行为。