Experimental design. A, Experimental time course. B, Left panel, IOS responses to stimulation of individual whiskers are superimposed over the superficial vasculature (dark blue, C1; light blue, C2; green, D1) and are used to position a standard map of the barrel field (barrels outlined in white). Right panel, GFP-expressing pyramidal cells are localized using 2PLSM and the position of the cells relative to the barrel map is determined. C, Overview of a L5 cell apical dendrite tuft imaged at days 0 and 56. The center of the tuft is positioned in barrel E3 (B, boxed area). D, Individual dendrite segments are imaged at high-magnification to monitor dendritic spine dynamics. The boxed areas in C indicate the position of the individual segments and arrowheads point to spines present over a 56 d time frame. E, F, Schematic illustrating the lesion paradigm. E, The removal of whisker follicles lesions the trigeminal nerve endings and causes permanent whisker deprivation. F, Side view of a mouse's snout after FR and the corresponding map of the contra-lateral barrel cortex. Note that a subset of whiskers is missing (red circles), whereas the remainder of the whiskers is left intact (green circles). This results in a partial deprivation of the barrel cortex (green, spared barrels; red, deprived barrels). The highlighted barrels correspond to the whiskers (C1, dark blue; C2, light blue; D1, green) used to map the barrel columns. C1 and C2 were used to measure map shifts with quantitative IOS measurements.