Testing a theory of avoidance learning & overgeneralization in chronic pain

测试回避学习理论

• 批准号: 10763110
• 负责人: Frederike Hermi Petzschner
• 金额: $ 39.31万
• 依托单位: BROWN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10763110
• 关键词: Testing; theory; avoidance; learning; overgeneralization

When we touch a hot stove or bang our foot against the living room table, it hurts. While irritating in the moment, acute pain serves an important purpose. First, it triggers an immediate defensive response to prevent or avoid further tissue damage. Second, it serves as a potent teaching signal to make sure we avoid making the same mistake in the future. This is an adaptive response if pain perception subsides when the tissue heals. However, when pain persists longer than 3 months, maladaptive learning processes in the brain that misinterpret these teaching signals may contribute to pain chronification. Analogous to a fire alarm that continues to ring even after the fire has been extinguished, the brain is thought to continue to predict that it is in a context of harm and engages in avoidance behavior even after the tissue has healed. Importantly these harm beliefs are thought to translate to other non-harm contexts, leading to an over-generalization of harm avoidance. This harm-avoidance model of pain ties in nicely with recent neuroimaging findings showing alterations in the fronto-striatal circuitry involved in the representation of context values and reinforcement learning in chronic pain Patients. However, the mechanism by which these interacting brain systems contribute to chronic pain or amelioration thereof is unknown. Here we expand a learning task and computational models in combination with EEG to differentiate between (PFC-driven) estimates of context values and (BG-driven) learning in chronic pain patients. Specifically, we test the hypothesis that avoidance learning in chronic pain patients may be driven by an overemphasis on learning from negative outcomes and an overgeneralization from one context of harm avoidance to other contexts. We hypothesize that this can be additionally observed in increased EEG frontal theta-band power in chronic patients during harm avoidance learning. Theta-band power has been previously shown to covary with the representation of context values and learning and thus provides an important read-out of biased learning throughout the task. This work will provide the basis for a future longitudinal research study where this task will be used to predict the risk of developing chronic pain after an acute pain state.

当我们触摸热气腾腾的炉子或把脚撞在客厅桌子上时，就会疼。在烦人的时候 在这一刻，剧烈的疼痛起着重要的作用。首先，它触发了对 防止或避免进一步的组织损伤。其次，它是一个强有力的教学信号，以确保我们 避免在未来犯同样的错误。如果痛觉减弱，这是一种适应性反应。 当组织愈合时。然而，当疼痛持续超过3个月时，适应不良的学习过程 错误解释这些教学信号的大脑可能会导致疼痛的时代化。类似于 即使在大火被扑灭后，火警仍在继续响起，人们认为大脑仍在继续 预测它处于伤害的背景下，并即使在组织已经 痊愈了。重要的是，这些伤害信念被认为转化为其他无害的背景，导致 过分泛化避免伤害。 这种疼痛的伤害-回避模型与最近的神经成像结果很好地联系在一起，显示出 前额-纹状体环路参与背景值表征和强化学习 慢性疼痛患者。然而，这些相互作用的大脑系统有助于 慢性疼痛或其改善情况尚不清楚。 在这里，我们扩展了一个学习任务和计算模型，并结合脑电进行区分 在慢性疼痛患者中(PFC驱动的)上下文值估计和(BG驱动的)学习之间。 具体地说，我们测试了一个假设，即慢性疼痛患者的回避学习可能是由一种 过分强调从负面结果中吸取教训，从一种危害的背景中过度泛化 对其他情况的回避。我们推测，在增加的脑电中还可以观察到这一点。 慢性疾病患者在避免伤害学习过程中的额叶theta-band功率。西塔频段的功率一直是 先前被示为与上下文值和学习的表示相同，从而提供了 在整个任务中，重要的是读出有偏见的学习。这项工作将为未来的 这项任务将被用来预测术后慢性疼痛风险的纵向研究 剧烈的疼痛状态。