Figure 4. Summary of classified VTA GABAergic neurons.

(A) Average r² values for yaw, roll, and pitch, as well as shuffled data from a Pearson Correlation (PC) analysis for neurons classified as pitch. (Pitch: r² = 0.83 ± 0.01; Roll: r² = 0.56 ± 0.03; Yaw: r² = 0.41 ± 0.05; Mean ± SEM). Correlation with pitch angle is significantly higher than correlation with roll and yaw angles (One-way ANOVA: F_(3,134) = 62.64, p < 0.0001; p values were corrected with Dunnett’s multiple comparison test. **** p < 0.0001).

(B-C) Because yaw and roll co-varied during horizontal tracking and had similar r² values when compared to the pitch population, we directly compared r² values between roll and yaw angle along with shuffled data for neurons classified as yaw or roll angle neurons.

(B) There is a significant difference between the r² values of yaw and roll angle for neurons categorized as roll neurons (One-way ANOVA, F_(2,195) = 60.31, p < 0.0001, Roll: r² = 0.87 ± 0.01; Yaw: r² = 0.54 ± 0.03; Mean ± SEM).

(C) There is also a significant difference between the r² values of yaw and roll angle for neurons categorized as yaw neurons (One-way ANOVA, F_(2,90) = 37.36, p < 0.0001, Yaw: r² = 0.83 ± 0.01; Roll: r² = 0.54 ± 0.05; Mean ± SEM).

(D) Normalized cross-correlations for yaw neurons (top), roll neurons (middle), and pitch neurons (bottom). Latency between neural activity and behavior were determined from cross-correlation analysis.

(E) Latency between neural activity and yaw angle for both Yaw (L↑ R↓; $\overline{\text{x}}$ = 180 ± 0.05 ms) and Yaw (L↓ R↑; $\overline{\text{x}}$ = 52 ± 0.09 ms; Mean ± SEM) neurons.

(F) Latency between neural activity and roll angle for both Roll (L↑ R↓; $\overline{\text{x}}$ = 60 ± 0.03 ms) and Roll (L↓ R↑; ($\overline{\text{x}}$ = 50 ± 0.03 ms; Mean ± SEM) neurons.

(G) Latency between neural activity and pitch angle for both Pitch (U↑ D↓; $\overline{\text{x}}$ = 130 ± 0.04 ms) and Pitch (U↓ D↑; $\overline{\text{x}}$ = 20 ± 0.07 ms; Mean ± SEM) neurons.

(H) Proportion of head angle neurons among all classified VTA GABAergic neurons.

(I) Number of yaw angle neurons that increase their firing rate in the ipsiversive direction (n = 23) or contraversive direction (n = 14) in relation to the recording hemisphere.

(J) Number of roll angle neurons that increase their firing rate in the ipsiversive direction (n = 37) or contraversive direction (n = 24) in relation to the recording hemisphere.

(K) Number of pitch angle neurons that increase their firing rate in the upward direction (n = 22) or downward direction (n = 14). See also Figure S4 and Videos S4 and S5.