Fisher's post-hoc analysis of spine morphology density on active and inactive neurons within experimental protocols. FC resulted in fewer mushroom spines on active compared to inactive neurons (*p < 0.05), and FC and UP resulted in fewer branched spines on active compared to inactive neurons (***p < 0.001 and p < 0.05, respectively). FC resulted in fewer thin spines on active compared to inactive neurons (p < 0.05). Filopodia spines were also measured but were rare and did not reveal any significant changes in response to experimental protocol or neural activity. Values represent mean spine number ± SEM per 30 μm dendrite. Statistical comparisons were made relative to group designated by black box within each row. *p < 0.05, **p < 0.01, ***p < 0.001. IA, Inactive neurons; A, active neurons.