School of Education, Bar-Ilan University, Ramat-Gan 52900, Israel.
School of Education, Bar-Ilan University, Ramat-Gan 52900, Israel; The Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan 52900, Israel.
Cognition. 2019 Dec;193:104021. doi: 10.1016/j.cognition.2019.104021. Epub 2019 Aug 13.
Studies have demonstrated that similarly to individuals with PTSD, non-PTSD individuals with repeated traumatic-exposure display selective impairments in hippocampal-related functions. A central example is their impaired generalization learning. Interestingly, previous findings revealed that the nature of this impairment varied as a function of occupation; while firefighters display impaired generalization of negative context, police crime scene investigators (CSI) display impaired generalization of negative cue. One possible explanation for these discrepancies may relate to the different job requirements and unique training. Specifically, firefighters are primed to regard the context during traumatic events whereas CSI police are primed to regard specific objects (cues) in the environment. The aim of the present study was to examine the interactive effect of exposure and training on generalization learning. Eighty-two healthy volunteers were exposed to either neutral or traumatic images while receiving instructions to refer either to the images' general contexts or to their specific cues. It was found that while both groups equally acquired and retained stimulus-outcome associations, only participants who were exposed to traumatic images showed impaired generalization learning. This impairment demonstrated a particular difficulty to generalize negative but not positive outcomes. Most importantly, as expected, there was a significant interaction between type of training and the observed impairments. Specifically, individuals who were previously trained to refer to general contexts showed a selective overgeneralization of negative contexts, while individuals who were trained to refer to specific cues displayed a selective overgeneralization of negative cues. The results suggest that trauma exposed individuals show the most vulnerability in precisely the areas in which they were most trained. We discuss the ways in which improving generalization learning may impact individuals' process of trauma recovery and might set the ground for developing treatment and prevention methods.
研究表明，与 PTSD 个体类似，反复经历创伤的非 PTSD 个体在海马体相关功能上存在选择性损伤。一个典型的例子是他们受损的泛化学习能力。有趣的是，先前的研究发现，这种损伤的性质因职业而异；消防员表现出负面情境的泛化受损，而警察犯罪现场调查员（CSI）则表现出负面线索的泛化受损。这些差异的一个可能解释可能与不同的工作要求和独特的训练有关。具体来说，消防员在创伤性事件中被激发去关注情境，而 CSI 警察则被激发去关注环境中的特定物体（线索）。本研究旨在探讨暴露和训练对泛化学习的交互作用。82 名健康志愿者暴露于中性或创伤性图像中，同时接受指令，将注意力集中在图像的一般情境或特定线索上。结果发现，虽然两组参与者都同样获得和保留了刺激-结果的关联，但只有暴露于创伤性图像的参与者表现出泛化学习受损。这种损伤表现为对负面结果而非正面结果的特定泛化困难。最重要的是，正如预期的那样，训练类型和观察到的损伤之间存在显著的交互作用。具体来说，之前接受过关注一般情境的训练的个体表现出对负面情境的选择性过度泛化，而接受过关注特定线索的训练的个体则表现出对负面线索的选择性过度泛化。研究结果表明，暴露于创伤的个体在他们最受训练的领域表现出最大的脆弱性。我们讨论了改善泛化学习可能对个体创伤恢复过程的影响，并为开发治疗和预防方法奠定了基础。
