Deafferentation and Network Dysregulation Hypotheses in Charles Bonnet Syndrome (CBS) Mechanisms
DOI:
https://doi.org/10.58445/rars.3600Keywords:
Charles Bonnet Syndrome, functional connectivity, visual network, deafferentation, default mode network, fMRIAbstract
Charles Bonnet Syndrome (CBS) is a rare condition characterized by complex, persistent visual hallucinations (VH) in patients with normal cognitive function and vision impairment. At present, the cause of CBS remains unclear; there is evidence that deafferentation, hallucinations caused by a deprivation of visual stimuli, which propagates neural hyperactivity through cortical excitability, is considered a putative mechanism by which CBS arises. However, emerging research posits that the condition stems from changes in sensory and control neural networks. Studies have shown reorganization of functional connectivity among different systems, including the default mode network (DMN), salience network (SN), and visual network (VN) in CBS patients, modeling alterations in brain activity. By comparing various neural network models, this review evaluates the extent to which different hypotheses drive visual hallucinations in CBS patients. Therefore, we propose a multi-stage process which systematically combines the two hypotheses in order to clarify the underlying mechanisms behind CBS.
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