Extended Data Fig. 1: Assembly of MR saddle coil, mouse head-plate, and Ca²⁺ imaging optical apparatus. Custom saddle coil and imaging apparatus design.

a, Removable saddle coil, with case that protects hardware. b, Coil in place on dual imaging sled. Coil (white) is mounted on a support system (blue) which is fixed to the sled (semi-transparent blue). A support system for the mouse (orange) is attached to the sled to which the mouse head plate (red) attaches. c, Assembled dual imaging apparatus. The telecentric lens (for Ca²⁺ imaging) is secured above the mouse and saddle coil. The position of the telecentric lens (and housing) can be adjusted (yellow) along the magnet B_o axis to focus the Ca²⁺ image.