SHANK1 and Anxiety: Mice completely lacking all Shank1 protein isoforms (Shank1–/– mice) have increased anxiety-related behavior, impaired contextual fear memory and object recognition memory (Hung et al., 2008; Sungur et al., 2017), as well as social communication/interaction deficits (Wohr et al., 2011; Sungur et al., 2016).