One other study using actigraphy reported that a loss in AVP neurons in the SCN in AD patients was associated with fragmented rhythmicity compared to healthy aged-matched controls (Harper et al., 2008), however, this group used a ratio of AVP neurons to glial cells in only a few selected fields of the SCN, whereas Wang et al. (2015) used a stereological rigorous method to quantify AVP and VIP throughout the entire nucleus. The gene discussed is VIP; the disease is Alzheimer disease.