Lissek Silke, Tegenthoff Martin
Department of Neurology, BG University Hospital Bergmannsheil, Ruhr University Bochum, Bochum, Germany.
Front Behav Neurosci. 2025 Jul 3;19:1592929. doi: 10.3389/fnbeh.2025.1592929. eCollection 2025.
The renewal effect of extinction describes the reoccurrence of an extinguished response if recall is performed in a context that is not the same as the extinction context. This learning phenomenon is clinically relevant, since it potentially interferes with therapy success for anxiety disorders or phobias. The propensity to show the renewal effect appears to be a stable processing strategy in context-related extinction, associated with higher BOLD activation in hippocampus, ventromedial PFC (vmPFC) and inferior frontal gyrus (IFG) in individuals who show renewal (REN) compared to those who do not (NoREN). However, evidence on a potential relationship between structural properties such as gray matter volume (GMV) in these regions and the propensity to show renewal is lacking.
In this study, we applied voxel-based morphometry (VBM) to investigate whether individuals with and without a propensity for renewal differ regarding their GMV in extinction-related brain regions, and whether such a difference is linked to the renewal level.
Results revealed differential GMV in REN and NoREN in adjacent subregions of IFG and vmPFC, respectively. Higher GMV in REN was located predominantly in orbital IFG and in BA10 of vmPFC. Higher GMV in NoREN was located predominantly in triangular IFG and in BA 11 of vmPFC. In bilateral anterior cingulate cortex (ACC) and anterior hippocampus, GMV was overall higher in NoREN. In the complete sample, higher GMV in IFG BA 47, vmPFC BA11, bilateral ACC and bilateral anterior hippocampus was associated with less renewal, and partially with a higher error level in extinction learning in a novel context.
The findings suggest that higher GMV in several regions active during extinction learning may support a more thorough processing of extinction trials which in turn could be conducive to an extinction recall solely based on recent extinction memory, disregarding context information. In summary, this study provides first-time evidence for a relationship of GMV in of extinction- and renewal-relevant brain regions with behavioral performance during extinction learning and the propensity to show the renewal effect.
消退的恢复效应描述了如果在与消退情境不同的背景下进行回忆，已消退反应会再次出现。这种学习现象在临床上具有相关性，因为它可能会干扰焦虑症或恐惧症的治疗效果。表现出恢复效应的倾向似乎是情境相关消退中的一种稳定加工策略，与表现出恢复效应（REN）的个体相比，未表现出恢复效应（NoREN）的个体在海马体、腹内侧前额叶皮质（vmPFC）和额下回（IFG）中具有更高的血氧水平依赖（BOLD）激活。然而，这些区域的灰质体积（GMV）等结构特性与表现出恢复效应的倾向之间潜在关系的证据尚不存在。
在本研究中，我们应用基于体素的形态测量法（VBM）来研究有和没有恢复倾向的个体在与消退相关的脑区的GMV是否存在差异，以及这种差异是否与恢复水平相关。
结果显示，REN组和NoREN组在IFG和vmPFC的相邻亚区域分别存在不同的GMV。REN组中较高的GMV主要位于眶部IFG和vmPFC的BA10区。NoREN组中较高的GMV主要位于三角部IFG和vmPFC的BA11区。在双侧前扣带回皮质（ACC）和前海马体中，NoREN组的GMV总体上更高。在整个样本中，IFG的BA47区、vmPFC的BA11区、双侧ACC和双侧前海马体中较高的GMV与较少的恢复相关，并且部分与在新情境中消退学习时较高的错误水平相关。
研究结果表明，在消退学习期间活跃的几个区域中较高的GMV可能支持对消退试验进行更彻底的加工，这反过来可能有利于仅基于最近的消退记忆进行消退回忆，而忽略情境信息。总之，本研究首次提供了与消退和恢复相关的脑区的GMV与消退学习期间的行为表现以及表现出恢复效应的倾向之间关系的证据。
