Fig. 3. Quantitative analysis of MDT migration of interneurons in the MZ and VZ. (A,B) Quantification of the migration direction of GFP neurons in the MZ. Most GFP neurons migrated (80±1%; n=1132/1412 neurons, five hemispheres; see Materials and methods for the definition of migrating neurons). 0° represents medial and 90° rostral migration. The horizontal plane was subdivided into 24 (A), four (B, left panel) or two sectors (B, right panel), and the proportion of the neurons migrating in each sector was analysed (n=1132 neurons, five hemispheres). The proportion of neurons in each sector is shown by the histogram (average±s.e.m.). Note that rostrally migrating neurons outnumber those migrating medially (B, left panel). (C,D) As for A and B, but for VZ GFP neurons. Almost all GFP neurons migrated (96±2%; n=474/496 neurons, four hemispheres). In the upper part of A and C, overall distribution is also shown by polar coordinates. All data were from E13.5 mice. *P<0.03, **P<0.02, ***P<0.01 (Mann–Whitney U-test). M, medial; R, rostral; L, lateral; C, caudal.