Figure 2. Pcdh9-Cre;Tbx5^fl/fl mice show selective defects in vertical motion detection.

(A-D) Optokinetic reflex (OKR) results in adult Tbx5^+/+ and Pcdh9-Cre;Tbx5^fl/fl mice in response to nasotemporal (A), temporonasal (B), ventrodorsal (C), or dorsoventral (D) continuous motion, measured by scoring eye tracking movements (ETMs) per minute (arrows). Pcdh9-Cre;Tbx5^fl/fl mice exhibited absent OKRs in both the ventrodorsal and dorsoventral directions. Data presented as mean ± SD. (E-H) Pcdh9-Cre;Tbx5^fl/fl animals showed reduced gain in response to vertical sinusoidal stimuli (E) and enhanced gain in response to horizontal sinusoidal stimuli (F). Pcdh9-Cre;Tbx5^fl/fl mice demonstrated enhanced vertical gain in response to horizontal stimuli (G) and enhanced horizontal gain in response to vertical stimuli (H). Data presented as mean ± IQR with whiskers representing the range. (I-L) Tbx5^+/+ and Pcdh9-Cre;Tbx5^fl/fl mice both performed voluntary horizontal and vertical saccades. (M) Pcdh9-Cre;Tbx5^fl/fl mice showed normal performance on the visual cliff task, a measure of depth perception (dashed line represents chance performance). Data presented as mean ± SD. (N) Pcdh9-Cre;Tbx5^fl/fl mice showed normal escape behaviors on the looming task, a measure of the ability to detect overhead looming stimuli. N, nasal. T, temporal. D, dorsal. V, ventral. *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001. See also Figure S2.