Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
Neuroimage. 2020 Sep;218:117005. doi: 10.1016/j.neuroimage.2020.117005. Epub 2020 May 30.
Individuals with congenital sensory deprivation usually demonstrate altered brain morphology in areas associated with early processing of the absent sense. Here, we aimed to establish whether this also applies to individuals born without a sense of smell (congenital anosmia) by comparing cerebral morphology between 33 individuals with isolated congenital anosmia and matched controls. We detected no morphological alterations in the primary olfactory (piriform) cortex. However, individuals with anosmia demonstrated gray matter volume atrophy in bilateral olfactory sulci, explained by decreased cortical area, curvature, and sulcus depth. They further demonstrated increased gray matter volume and cortical thickness in the medial orbital gyri; regions closely associated with olfactory processing, sensory integration, and value-coding. Our results suggest that a lifelong absence of sensory input does not necessarily lead to morphological alterations in primary sensory cortex and extend previous findings with divergent morphological alterations in bilateral orbitofrontal cortex, indicating influences of different developmental processes.
先天性感觉剥夺的个体通常在与缺失感觉的早期处理相关的区域表现出大脑形态的改变。在这里，我们通过比较 33 名孤立性先天性嗅觉丧失患者和匹配的对照组的大脑形态，旨在确定这种情况是否也适用于没有嗅觉的个体（先天性嗅觉缺失）。我们在初级嗅觉（梨状皮层）皮质中未发现形态改变。然而，嗅觉丧失者在双侧嗅沟中表现出灰质体积萎缩，这归因于皮质面积、曲率和沟深度的减少。他们进一步在眶内回中显示出灰质体积和皮质厚度增加；这些区域与嗅觉处理、感觉整合和价值编码密切相关。我们的结果表明，终生缺乏感觉输入不一定会导致初级感觉皮层的形态改变，并扩展了以前在双侧眶额皮层中存在的形态改变的发现，表明不同发育过程的影响。
