Table 1.

Coordinates for IBO injection

Coordinates (in mm)
A–P	M–L	D–V
2.2	0.8	4.2
3.0	1.5	3.6*, 4.4*
3.0	3.0	4.0
4.0	2.5	3.5*, 4.5*
4.0	3.6	4.0
4.8	3.2	4.5
4.8	4.3	4.2, 6.0
5.7	4.1	4.5
5.7	5.1	4.0*, 4.8, 5.6

The bregma was used as a zero point to measure the anterior to posterior (A–P) and medial to lateral (M–L) coordinates. Dorsal to ventral (D–V) positions were measured from the skull at the bregma. Bregma and lambda were on the same horizontal plane. In some A–P coordinates, multiple M–L and D–V positions were used to inject the IBO. The injection quantity of the IBO for each position was 0.1 μl, except for the star (*) denoted mark, where 0.05 μl was injected.