Differences in cell number early in culture. Cells were plated at an initial density of 60,000 cells/cm2. (A) The number of neurons was determined 24 hours after plating. **p<0.01 and ***p<0.001 determined by Kruskal-Wallis Test followed by Dunn’s Multiple Comparison Test compared to cultures grown on 0.02% bis-acrylamide gels. (B) The number of neurons was determined 48 hours after plating. **p<0.01 determined by Kruskal-Wallis Test followed by Dunn’s Multiple Comparison Test compared to cultures grown on 0.02% gels. (C, D) Representative images of neurons cultured on 0.02 and 0.06 % bis-acrylamide gels quantitated in panels A and B. Scale bar = 50 µm. The numbers of pictures taken for each condition are listed for cultures grown on 0.02, 0.03, 0,01, and 0.06% bis-acrylamide gels, respectively. 24 hours: n=30; 55; 56; 55. 48 hours: n=43; 49; 54; 55. Data were averaged across four experiments. All data are represented as mean ± SEM.