Figure 4.
Summary of measurements of apical dendritic spines of layer V pyramidal neurons in temporal cortex of human autopsy samples of male patients with fragile X syndrome (FraX) and age- and sex-matched controls. (A) Arbitrary spine shape categorization scheme. Each spine was categorized as falling into one of the eight shape categories. (B) Relative numbers of spines of each type. Overall χ2 is significant (P < 0.05). Principal differences are relatively greater immature spine types C and D and fewer mature spine types F and G in affected individuals. (C) Numerical density of spines per unit length of dendrite is higher in affected individuals (*, P < 0.05). (D) Affected individuals have fewer short (0.5-μm) and more long (≥1.5-μm) spines. Overall χ2 is significant (P < 0.05). Data are from ref. 28.