Refinements to rodent head fixation and fluid/food control for neuroscience by Barkus, C, Bergmann, C, Branco, T, Carandini, M, Chadderton, PT, Galiñanes, GL, Gilmour, G, Huber, D, Huxter, JR, Khan, AG, King, AJ, Maravall, M, O'Mahony, T, Ragan, CI, Robinson, ESJ, Schaefer, AT, Schultz, SR, Sengpiel, F, Prescott, MJ