Fig. 1.

Morphological and morphometrical characteristics used for spine classification. (Left) Four different morphological (shape) types were identified and categorized based on morphometrical features (criteria), as indicated. hd, head diameter; nd, neck diameter; nL, neck length; TL, total length. (Right) Example of a typical observation made on the dendritic tree of an MSN belonging to a rat of the control group. The image is color-coded. Colored bands on dendrites indicate the origin of spines.