Fig. 1
Aged mice do not show robust escape behavior in response to looming stimulus. (a) Representation of the behavioral apparatus generating looming stimulus (left). The stimulus is presented when the mouse enters a virtual central zone (orange dotted circle) according to the indicated timing (right). (b) Percentage of young (3–4 months) and aged (23–25 months) mice in the “Control” (Ctrl) or “Looming” (Loom) conditions showing exploration or innate fear behavioral responses during looming stimulus. (c) Latency to escape to the shelter after stimulus onset for young (n = 11) and aged (n = 7) mice. Data are represented by the median (female and male mice are respectively represented by circles and triangles), **** p < 0.0001. Speed of young (d) and aged (e) mice in the “Control” (Ctrl, n = 7 young, n = 8 aged) or in the “Looming” (n = 12 young, n = 21 aged) groups for 10 s before (-10 to 0 s) and during (0 to 10 s) the stimulus. The performance of young and aged control mice is centered on their entry into the virtual central zone, even though the stimulus was not displayed for them. The performance of aged mice is displayed in 2 groups: animals showing only a freezing response (no escape behavior) (light purple, n = 14) and those showing both escape and freezing behavior (dark purple, n = 7). Each gray bar represents a looming stimulus, as shown in a. Data are represented as mean ± SEM.
