Table 2.

Summary of turning behaviors resulting from micro-CALI of NCAM-180

Behavior	Frequency observed for each treatment
Treatment	Micro-CALI  using 4d	Micro-CALI  using 5e	Micro-CALI  Control IgG
Regional retraction	21/25*	3/20	2/20
Lateral growth cone movement	16/25	4/20	3/20
Movement away	14/16**	2/4	1/3
Movement toward	2/16	2/4	2/3
Odds ratio of moving away	7.0***	1.0	0.5

Comparison of growth cone retraction and turning observed during micro-CALI of NCAM experiments. Regional retraction is defined as a decrease in length of the cord drawn from the neurite neck to the furthest extent of the leading edge within the area of irradiation during CALI. Lateral growth cone movement (defined operationally as components of leading edge extension that are perpendicular to the midline of the growth cone) was observed before and after micro-CALI, and changes in lateral movement were scored. “Moving away” means that the leading edge of the non-laser irradiated side is extending away from the laser spot and does not simply denote lamellipodial retraction. Of the growth cones that moved away from the laser spot, 93% also exhibited filopodial retraction for micro-CALI experiments targeting the intracellular domain of N-CAM 180 of cells growing on laminin. The odds ratio assumes a 50% probability for a change in lateral growth cone movement to be away from the laser spot (odds ratio = 1).

*p < 0.002 by Poisson's test.

**p < 0.02, significantly associated with filopodial retraction by McNemar's exact test.

***p < 0.02 by one-sample binomial test.