(A) Relative frequency plot of retraction distance categorized by DIV. Average distance comparison between 4 DIV and 24 DIV: Welch’s t-test. (B) Retraction distance categorized separately by DIV, retraction, and axotomy distance. 16 DIV: One-way ANOVA followed by Bonferroni’s post hoc test, 24 DIV: Welch’s t-test. (C) Regeneration ratio categorized by DIV, retraction, and axotomy distance. 16 DIV: Fisher’s exact test with Bonferroni correction, 16 DIV proximal axotomy vs 24 DIV proximal axotomy: Fisher’s exact test, 24 DIV: Fisher’s exact test. (D,E,F) Regeneration initiation time, regeneration length and growth cone area categorized by DIV. One-way ANOVA followed by Games-Howell post hoc test. (G) Plot of regeneration success against log retraction distance. Error bars represent s.e.m. Axotomy results were accumulated from at least three independent axotomy sessions. Retraction distance was converted by log10. *p<0.05, **p<0.01, ***p<0.001 and ****p<0.0001.