Schneider U, Leweke F M, Mueller-Vahl K R, Emrich H M
Department of Clinical Psychiatry and Psychotherapy, Medical School, Hannover, Germany.
Pharmacopsychiatry. 1998 Jul;31 Suppl 2:110-3. doi: 10.1055/s-2007-979355.
Cognitive impairments during psychotic episodes are assumed to be caused not only by one single putative classical neurotransmitter dysfunction but also to be due to an impaired equilibrium of the interaction between different neurobiological generators of cognitive processes. Here, the perceptual abnormalities induced by psychotogenic agents play a major role as tools for understanding model psychoses. The recently discovered cannabinoid receptor system with its endogenous ligand anandamide can be regarded as an extremely relevant regulation system, a dysfunctionality of which may explain at least one subtype of endogenous psychoses. The present paper discusses the possible associations between the endogenous anandamide/cannabinoid system and schizophrenic psychoses. Neuropsychological experiments with the 3-D inversion paradigm were performed in healthy volunteers intoxicated with delta9-Tetrahydrocannabinol (delta9-THC). The 3-D inversion paradigm represents a visual illusion of binocular depth perception. Such an inversion occurs in many cases, especially when objects with a higher degree of familiarity (e.g. photographs of faces) are displayed. It is assumed that cognitive factors override the binocular disparity cues of stereopsis. We tested the hypothesis that, during psychotic and related prepsychotic states, the human CNS is unable to correct implausible perceptual hypotheses. Our study provides evidence of strong similarities between data acquired from patients, suffering from productive schizophrenic psychoses and delta9-THC-intoxicated healthy volunteers, as concerns disturbances in the internal regulation of perceptual processes.
精神病发作期间的认知障碍被认为不仅是由单一的假定经典神经递质功能障碍引起的，还归因于认知过程的不同神经生物学发生器之间相互作用的平衡受损。在这里，致幻剂引起的感知异常作为理解模型精神病的工具发挥着重要作用。最近发现的大麻素受体系统及其内源性配体花生四烯乙醇胺可被视为一个极其相关的调节系统，其功能失调可能至少解释了内源性精神病的一种亚型。本文讨论了内源性花生四烯乙醇胺/大麻素系统与精神分裂症性精神病之间可能的关联。在服用δ9-四氢大麻酚（δ9-THC）的健康志愿者中进行了三维反转范式的神经心理学实验。三维反转范式代表了双眼深度感知的视觉错觉。这种反转在许多情况下都会发生，尤其是当显示具有较高熟悉度的物体（如面部照片）时。据推测，认知因素超越了立体视觉的双眼视差线索。我们检验了这样一个假设，即在精神病发作及相关的精神病前期状态下，人类中枢神经系统无法纠正不合理的感知假设。我们的研究提供了证据，表明在感知过程的内部调节紊乱方面，从患有阳性精神分裂症性精神病的患者和服用δ9-THC的健康志愿者身上获得的数据有很强的相似性。
