Extended Data Fig. 6: Lesion of dopamine neurons altered Ca²⁺ event rates in dSPNs and iSPNs during spontaneous open field exploration and forced movement on the rotarod.

a, b, Cumulative probability distributions of Ca²⁺ event rates in dSPNs (left) and iSPNs (right) while mice were resting (a) or in locomotion (b) before the lesion of dopamine neurons, 1 day after the lesion (day 1), and >14 day after the lesion (day 14). Ca²⁺ event rates in dSPNs were depressed at both time points after the lesion, during rest and locomotion. Ca²⁺ event rates in iSPNs were elevated at both time points after the lesion when mice were resting. However, when the mice were moving, iSPN activity rates were elevated at 1 day but not >14 days after the lesion, compared to values from before the lesion. The distributions of Ca²⁺ event rates in dSPNs in resting mice were nearly identical at 1 and >14 days, making it hard to visually distinguish the two plots. Data are from 12 Drd1a^cre mice and 13 Adora2a^cre mice. The Drd1a^cre mice yielded a total of 2,554–3,732 activated dSPNs during movement and rest, across the different days of the study, whereas the Adora2a^cre mice yielded 3,209–3,702 iSPNs. All comparisons within each SPN type between Ca²⁺ event rates from before the lesion to those 1 d and 14 d after the lesion were significant. P < 10⁻³; Wilcoxon rank-sum test. c, Cumulative distribution functions of Ca²⁺ event rates in individual dSPNs and iSPNs as mice walked on the rotarod. At 1 day after dopamine depletion (day 1), Ca²⁺ event rates were reduced in dSPNs and increased in iSPNs. At >14 days after dopamine depletion (day 14), Ca²⁺ event rates were still reduced in dSPNs but in iSPNs were at or even slightly below normal values. Data pre-lesion and >14 days after dopamine depletion are based on 5 Drd1a^cre mice and 7 Adora2a^cre mice; however, 1 day after dopamine depletion only 2 Drd1a^cre mice and 3 Adora2a^cre mice could perform the rotarod assay without falling off, precluding determinations of Ca²⁺ event rates from the other mice on that day. All comparisons within each SPN type between Ca²⁺ event rates from before the lesion to those 1 and >14 days after the lesion were highly significant (P < 10⁻¹⁰; Wilcoxon rank-sum test), except for the comparison of iSPN activity rates from before the lesion to those >14 days after (P = 5 × 10⁻³; Wilcoxon rank-sum test). d, Rates of Ca²⁺ events (mean ± s.e.m.) as mice walked on the rotarod, normalized to the corresponding values from before dopamine depletion. dSPN activation rates were substantially reduced at both time points after the lesion. iSPN event rates were substantially increased 1 day after the lesion (day 1), but had returned to near baseline levels by 14 days after the lesion (day 14), mirroring the effects of dopamine depletion on dSPN and iSPN activity during spontaneous movement (see Fig. 3f). **P < 5 × 10⁻³ and ***P < 5 × 10⁻⁷; Wilcoxon rank-sum test. Owing to the large numbers of Ca²⁺ events across thousands of SPNs that contributed to these calculations, the slight depression of Ca²⁺ event rates in iSPNs at 14 days after the lesion was statistically significant. e, The extent of pairwise coactivation of dSPNs (left) and iSPNs (right) during the rotarod assay, as a function of the pairwise distance between cells, before dopamine depletion, at 1 and >14 days after dopamine depletion. Values are normalized to those attained from shuffled datasets in which the times of the Ca²⁺ events of each cell were randomized (Methods). The spatial clustering of activity in proximal iSPN pairs (20–100 μm apart) was significantly reduced 14 days after the lesion, relative to values from beforehand. P < 10⁻¹⁶; Wilcoxon rank-sum test; n = 7 Adora2a^cre mice. Shaded areas denote s.e.m. Data and statistical tests in c–e are from 1,930, 712 and 1,672 dSPNs and 1,731, 853 and 1,607 iSPNs that were active during the rotarod assay pre-lesion, 1 (day 1), and 14 (day 14) days after the lesion, respectively.