NEFL and Cognitive impairment: Similarly, Kanberg et al. [41] demonstrated that despite the presence of cognitive symptoms, biomarkers indicative of active neurodegeneration (such as neurofilament light chain (NfL) or glial fibrillary acidic protein (GFAP)) were not observed, reinforcing the hypothesis that the cognitive deficits are not due to neurodegenerative processes but likely to transient functional or inflammatory mechanisms related to the infection.