Martino Matteo, Magioncalda Paola
Graduate Institute of Mind Brain and Consciousness, Taipei Medical University, Taipei, Taiwan.
International Master/Ph.D. Program in Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
Mol Psychiatry. 2024 Dec;29(12):3814-3825. doi: 10.1038/s41380-024-02607-4. Epub 2024 Jun 6.
According to classical phenomenology, phenomenal experience is composed of perceptions (related to environmental stimuli) and imagery/ideas (unrelated to environmental stimuli). Intensity/vividness is supposed to represent the key phenomenal difference between perceptions and ideas, higher in perceptions than ideas, and thus the core subjective criterion to distinguish reality from imagination. At a neural level, phenomenal experience is related to brain activity in the sensory areas, driven by receptor stimulation (underlying perception) or associative areas (underlying imagery/ideas). An alteration of the phenomenal experience that leads to a loss of contact with reality characterizes psychosis, which mainly consists of hallucinations (false perceptions) and delusions (fixed ideas). According to the current data on their neural correlates across subclinical conditions and different neuropsychiatric disorders (such as schizophrenia), hallucinations are mainly associated with: transient (modality-specific) activations of sensory cortices (primarily superior temporal gyrus, occipito-temporal cortex, postcentral gyrus, and insula) during the hallucinatory experience; increased intrinsic activity/connectivity of associative/default-mode network (DMN) areas (primarily temporoparietal junction, posterior cingulate cortex, and medial prefrontal cortex); and deficits in the sensory systems. Analogously, delusions are mainly associated with increased intrinsic activity/connectivity of associative/DMN areas (primarily medial prefrontal cortex). Integrating these data into our three-dimensional model of neural activity and phenomenal-behavioral patterns, we propose the following model of psychosis. A functional/structural deficit in the sensory systems complemented by a functional reconfiguration of intrinsic brain activity favoring hyperactivity of associative/DMN areas may drive neuronal activations in the sensory (auditory/visual/somatosensory) areas and insular (interoceptive) areas with spatiotemporal configurations maximally independent from environmental stimuli and predominantly related to associative processing. This manifests in perception deficit and imagery/ideas composed of exteroceptive-like and interoceptive/affective-like elements that show a phenomenal intensity indistinguishable from perceptions, impairing the reality monitoring, along with minimal changeability by environmental stimuli, ultimately resulting in dissociation of the phenomenal experience from the environment, i.e., psychosis.
根据经典现象学，现象体验由感知（与环境刺激相关）和意象/观念（与环境刺激无关）组成。强度/生动性被认为代表了感知和观念之间关键的现象学差异，感知中的强度/生动性高于观念，因此是区分现实与想象的核心主观标准。在神经层面，现象体验与感觉区域的大脑活动相关，由受体刺激（感知的基础）或联合区域（意象/观念的基础）驱动。导致与现实失去联系的现象体验改变是精神病的特征，精神病主要由幻觉（错误感知）和妄想（固定观念）组成。根据目前关于其在亚临床状况和不同神经精神疾病（如精神分裂症）中的神经关联的数据，幻觉主要与以下因素相关：幻觉体验期间感觉皮层（主要是颞上回、枕颞叶皮层、中央后回和脑岛）的短暂（特定模态）激活；联合/默认模式网络（DMN）区域（主要是颞顶联合区、后扣带回皮层和内侧前额叶皮层）内在活动/连接性增加；以及感觉系统的缺陷。类似地，妄想主要与联合/DMN区域（主要是内侧前额叶皮层）内在活动/连接性增加相关。将这些数据整合到我们的神经活动和现象-行为模式的三维模型中，我们提出了以下精神病模型。感觉系统的功能/结构缺陷，辅以内在大脑活动的功能重新配置，有利于联合/DMN区域的过度活跃，这可能驱动感觉（听觉/视觉/体感）区域和岛叶（内感受）区域的神经元激活，其时空配置最大程度地独立于环境刺激，并且主要与联合加工相关。这表现为感知缺陷以及由类似外感受和类似内感受/情感的元素组成的意象/观念，这些元素表现出与感知难以区分的现象学强度，损害现实监测，并且对环境刺激的可变性极小，最终导致现象体验与环境分离，即精神病。
