GAP43 and Cognitive impairment: Moreover, no correlation between the content of GAP43 protein in serum and the SSPI scores was observed, indicating that the content of GAP43 protein in serum of patients was not correlated with the severity of cognitive impairment such as patient abstract generalization, cognitive transfer, attention, working memory, information extraction, classification maintenance, classification conversion, stimulation recognition and processing, sensory input, and motor output.