Plasticity of dendritic spine formation: a state-dependent stochastic process.
This study proposes that plasticity of dendritic spine formation may be modeled as distribution patterns imbedded in a spine length-dependent and density-dependent stochastic process. Modeling the jewel fish tectal interneuron revealed a critical 10-36 micron region where spine length plasticity was predicted to be most detectable. This hypothesis was tested by comparing neurons sampled from jewel fish reared for 4 years in a crowded environment (1 fish/5.64 l) with uncrowded controls (1 fish/25 l). The interaction between fish groups and the location of spine length differences was significant (p less than 0.01) within the basal 10-30 micron dendritic segment. Spine head widths were also significantly smaller (p less than 0.01) in the crowded fish over the entire dendrite. These findings suggest two modes of neuronal plasticity: (1) plasticity of spine length during formation, and (2) plasticity in spine head width after the spine is formed.
D000818:Animals; D003441:Crowding / Q000502:physiology; D003712:Dendrites / Q000648:ultrastructure*; D005399:Fishes; D007395:Interneurons / Q000648:ultrastructure; D008959:Models, Neurological; D012931:Social Environment; D013269:Stochastic Processes; D013477:Superior Colliculi / Q000033:anatomy & histology