Department of Psychology, Biological Psychology, University of Cologne, Cologne 50969, Germany
Department of Psychology, Biological Psychology, University of Cologne, Cologne 50969, Germany.
eNeuro. 2024 Jul 23;11(7). doi: 10.1523/ENEURO.0465-23.2024. Print 2024 Jul.
Psychotic symptoms and delusional beliefs have been linked to dopamine transmission in both healthy and clinical samples and are assumed to result at least in part from perceiving illusory patterns in noise. However, the existing literature on the role of dopamine in detecting patterns in noise is inconclusive. To address this issue, we assessed the effect of manipulating dopaminergic neurotransmission on illusory pattern perception in healthy individuals (= 48, = 19 female) in a double-blind placebo-controlled within-subjects design (see preregistration at https://osf.io/a4k9j/). We predicted individuals on versus off ʟ-DOPA to be more likely to perceive illusory patterns, specifically objects in images containing only noise. Using a signal detection model, however, we found no credible evidence that ʟ-DOPA compared with placebo increased false alarm rates. Further, ʟ-DOPA did not reliably modulate measures of accuracy, discrimination sensitivity, and response bias. In all cases, Bayesian statistics revealed strong evidence in favor of the null hypothesis. The task design followed previous work on illusory pattern perception and comprised a limited number of items per condition. The results therefore need to be interpreted with caution, as power was limited. Future studies should address illusory pattern perception using more items and take into account potential dose-dependent effects and differential effects in healthy versus clinical samples.
在健康和临床样本中，精神病症状和妄想信念都与多巴胺传递有关，并且假设至少部分源于感知噪声中的幻觉模式。然而，关于多巴胺在检测噪声中模式的作用的现有文献尚无定论。为了解决这个问题，我们在一项双盲安慰剂对照的个体内设计中评估了操纵多巴胺能神经传递对健康个体（= 48，= 19 名女性）感知幻觉模式的影响（请参见 https://osf.io/a4k9j/ 上的预先注册）。我们预测，与安慰剂相比，服用 ʟ-DOPA 的个体更有可能感知到幻觉模式，特别是在仅包含噪声的图像中感知到物体。然而，使用信号检测模型，我们没有发现可信的证据表明 ʟ-DOPA 与安慰剂相比会增加虚报率。此外，ʟ-DOPA 不能可靠地调节准确性、辨别敏感性和反应偏差的测量值。在所有情况下，贝叶斯统计都强烈支持零假设。任务设计遵循了先前关于幻觉模式感知的工作，每个条件的项目数量有限。因此，由于功率有限，结果需要谨慎解释。未来的研究应该使用更多的项目来解决幻觉模式感知问题，并考虑潜在的剂量依赖性效应和健康与临床样本之间的差异效应。
