Pharmacology, School of Biomedical Sciences, The University of Western Australia, Perth, WA, Australia.
Psychiatry, School of Medicine, The University of Western Australia, Perth, WA, Australia.
PLoS One. 2024 Sep 9;19(9):e0309614. doi: 10.1371/journal.pone.0309614. eCollection 2024.
Abnormally widened spatial and temporal binding windows (SBW/TBWs; length of space/time whereby stimuli are considered part of the same percept) are observed in schizophrenia. TBW alterations have been associated with altered sense of agency (hereafter referred to as agency), and an associative relationship between embodiment (body ownership) and agency has been proposed. SBWs/TBWs are investigated separately, but no evidence exists of these being separate in mechanism, system or function. The underlying neural substrate of schizophrenia remains unclear. The literature claims either pro-psychotic or anti-psychotic effects of Δ9-Tetrahydrocannabinol (THC) in patients and healthy individuals, but major support for cannabis in the aetiology of schizophrenia is associative, not causal. To clarify if THC is pro- or anti-psychotic, this single-blind, placebo-controlled within-subjects cross-over study tested several hypotheses. 1) Competing hypotheses that a synthetic THC analogue, Nabilone (NAB, 1-2 mg), would alter measures of agency and embodiment in healthy volunteers (n = 32) similarly, or opposite, to that of in patients with schizophrenia. 2) That there would be significant associations between any NAB-induced alterations in individual agency and embodiment measures in the Projected Hand Illusion (PHI). 3) That there is a unitary spatio-temporal binding window (STBW). A large proportion of individuals did not experience the PHI. Multimodal and bi-directional effects of NAB on the PHI were observed. Evidence of a unitary spatio-temporal binding window (STBW) was observed. NAB widened the STBW in some but narrowed it in others as a function of space and delay. No associations were found between agency and embodiment.
精神分裂症患者的空间和时间绑定窗口（SBW/TBWs；刺激被视为同一感知的一部分的空间/时间长度）异常扩大。TBW 的改变与代理感（以下简称代理）的改变有关，并且已经提出了体现（身体所有权）和代理之间的联想关系。SBWs/TBWs 是分开研究的，但没有证据表明它们在机制、系统或功能上是分开的。精神分裂症的潜在神经基础仍不清楚。文献声称 Δ9-四氢大麻酚（THC）在患者和健康个体中具有促精神病或抗精神病作用，但大麻在精神分裂症病因学中的主要作用是关联的，而不是因果关系。为了澄清 THC 是否具有促精神病或抗精神病作用，这项单盲、安慰剂对照、个体内交叉研究检验了几个假设。1）竞争假设，即合成 THC 类似物纳布酮（NAB，1-2 毫克）会以与精神分裂症患者相似或相反的方式改变健康志愿者（n = 32）的代理和体现测量值。2）在投射手错觉（PHI）中，任何 NAB 诱导的个体代理和体现测量值的变化之间存在显著关联。3）存在单一的时空绑定窗口（STBW）。很大一部分人没有体验到 PHI。在 PHI 中观察到 NAB 的多模态和双向作用。观察到单一的时空绑定窗口（STBW）的证据。NAB 在某些情况下扩大了 STBW，而在其他情况下则缩小了 STBW，这取决于空间和延迟。没有发现代理和体现之间的关联。
