Averaged F/F of cAMPinG1 in dendritic shafts and spines. n = 56 spines, n = 11 shafts in 4 mice. Boxes indicate the 25th and 75th percentiles, solid lines indicate the median, dashed lines indicate the mean, and whiskers indicate the total range of data. Unpaired two-tailed t -test. P = 4.3 10 -1 . All shaded areas and error bars denote the s.e.m. NS, not significant.