Abstract:
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 (n = 48, n = 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.
摘要:
精神病症状和妄想信念与健康和临床样本中的多巴胺传播有关,并且被认为至少部分是由于感知噪声中的虚幻模式所致。然而,关于多巴胺在检测噪声模式中的作用的现有文献尚无定论。为了解决这个问题,我们在双盲安慰剂对照的受试者内设计中评估了操纵多巴胺能神经传递对健康个体(n=48,n=19女性)虚幻模式感知的影响(参见https://osf.io/a4k9j/注册).我们预测个体在vs.离开L-DOPA更有可能感知到虚幻的模式,特别是仅包含噪声的图像中的对象。使用信号检测模型,然而,我们没有发现可靠的证据表明L-DOPA与安慰剂相比会增加误报率.Further,L-DOPA不能可靠地调节准确度,辨别灵敏度和反应偏差。在所有情况下,贝叶斯统计揭示了支持零假设的有力证据。任务设计遵循了先前关于虚幻模式感知的工作,每个条件包含有限数量的项目。因此,需要谨慎解释结果,因为权力是有限的。未来的研究应该使用更多的项目来解决虚幻的模式感知,并考虑到健康与健康的潜在剂量依赖性效应和差异效应临床样本。重要性陈述精神病和妄想信念与健康和临床样本中的多巴胺传播有关,并被认为部分是由于感知噪声中的虚幻模式所致。然而,关于多巴胺在检测虚幻模式中的作用的发现尚无定论。为了解决这个问题,我们评估了增强多巴胺传递对健康个体虚幻模式感知的影响.我们的假设,即增强多巴胺传递会增加参与者对噪声中虚幻模式的感知倾向,这一假设并未得到证实。这种无效效应表明,早期的发现可能不如以前认为的那么稳健,多巴胺和虚幻模式感知之间的关系可能会受到剂量依赖的影响,并且在健康与临床样本。