Both KCl and 5-HT treatments affect Helix morphological connectivity. (A) Bar graph of intra-cluster neurite density. We found that KCl application increased the number of neurites connecting the four cells of the same cluster. Conversely, a statistically significant reduction occurred after 5-HT treatment. Similar results were obtained considering the neurites projecting from one cluster to the other (inter-cluster density). B). While 5-HT induced an appreciable reduction, a less pronounced increase was detected in KCl-treated networks. (C) Bar graph of neurite outgrowth velocity showing that no growth defect was induced by the applied treatments.