Canna~Fangled Abstracts Audiograms, gap detection thresholds, and frequency difference limens in cannabinoid receptor 1 knockout mice. 2015 Sep 28. pii: S0378-5955(15)30148-9. doi: 10.1016/j.heares.2015.09.013. Toal KL1, Radziwon KE2, Holfoth DP3, Xu-Friedman MA4, Dent ML5. Author information…Freedom WaresSeptember 28, 2015