string: Frequency tuning and tonotopic organization in each field was consistent with earlier reports (Carrasco and Lomber 2011; Doron et al. 2002; Jakkamsetti et al. 2012; Pandya et al. 2008; Polley et al. 2007; Puckett et al. 2007; Takahashi et al. 2011, see METHODS and Fig.