Wolf Robert Christian, Schmitgen Mike M, Otte Marie-Luise, Karner Martin, Pycha Roger, Kirchler Erwin, Wolf Nadine Donata, Huber Markus
Department of General Psychiatry, Center for Psychosocial Medicine, Heidelberg University, Heidelberg, Germany.
DZPG, German Center for Mental Health, Partner Site Mannheim/Heidelberg/Ulm (ZIHUb), Heidelberg, Germany.
Psychogeriatrics. 2025 Jul;25(4):e70055. doi: 10.1111/psyg.70055.
Delusional disorders (DD) are among the most debilitating mental disorders in the elderly. Persistent monothematic delusions frequently include paranoid and persecutory beliefs, as well as various forms of somatic delusions, including delusions of being infested by pathogens. So far, little is known about the neural correlates of DD. Yet, particularly in elderly patients, white-matter lesions (WML) are thought to play an important pathophysiological role.
To investigate regional WML in patients with DD, structural MRI was used, followed by automated lesion segmentation methods to facilitate WML load (WMLL) comparisons between healthy controls (HC, n = 28) and patients with distinct types of DD, that is, somatic (n = 16) versus non-somatic DD (n = 17). Patients with somatic DD presented with specific delusional content, that is, beliefs of delusional infestation (DI), whereas individuals with non-somatic DD (non-DI) showed predominantly paranoid and persecutory content.
Regions with higher WMLL in both DI and non-DI patients compared to HC included the anterior cingulate and lateral prefrontal regions located in the middle frontal gyrus. Regions with higher WMLL in DI patients versus both HC and non-DI patients were predominantly located in the sensorimotor areas of the frontal lobe.
The data suggest distinct patterns of regional WMLL in elderly patients with DI versus non-DI. The anatomical distribution of WMLL supports a neuromechanistic model that emphasises the importance of brain areas that drive the internal bodily focus of somatic delusions versus the externalised cognitive distortions that can be observed in non-somatic delusions.
妄想障碍（DD）是老年人中最具致残性的精神障碍之一。持续性单主题妄想通常包括偏执和迫害性信念，以及各种形式的躯体妄想，包括被病原体感染的妄想。到目前为止，关于DD的神经相关性知之甚少。然而，特别是在老年患者中，白质病变（WML）被认为起着重要的病理生理作用。
为了研究DD患者的局部WML，使用了结构MRI，随后采用自动病变分割方法，以促进健康对照者（HC，n = 28）与不同类型DD患者（即躯体性DD患者，n = 16；非躯体性DD患者，n = 17）之间的WML负荷（WMLL）比较。躯体性DD患者表现出特定的妄想内容，即妄想性感染（DI）信念，而非躯体性DD患者（非DI）主要表现为偏执和迫害性内容。
与HC相比，DI患者和非DI患者中WMLL较高的区域包括前扣带回和位于额中回的外侧前额叶区域。与HC和非DI患者相比，DI患者中WMLL较高的区域主要位于额叶的感觉运动区。
数据表明老年DI患者与非DI患者的局部WMLL模式不同。WMLL的解剖分布支持一种神经机制模型，该模型强调了驱动躯体妄想的内部身体聚焦的脑区与非躯体妄想中可观察到的外部认知扭曲的脑区的重要性。
