Aberrant development of the Purkinje cell dendritic spine.
D000818:Animals; D002454:Cell Differentiation; D002525:Cerebellar Cortex / Q000166:cytology; D003712:Dendrites / Q000648:ultrastructure*; D051379:Mice; D008854:Microscopy, Electron; D009154:Mutation; D009410:Nerve Degeneration; D011689:Purkinje Cells / Q000166:cytology* / Q000648:ultrastructure