An increase in cortical and subcortical NGF has been found in patients with Alzheimer's disease. Alzheimer's is a neurodegenerative disease with which dysregulation of NGF signaling has also been linked, causing impaired retrograde transport of NGF to certain areas of the brain. This impairment may be caused by an atypical production or use of receptors in the brain. Stimulating NGF receptors via NGF infusion has been shown to increase blood flow and verbal episodic memory. These improvements have been longer lasting than other treatments for Alzheimer's.