Article Figures & Data
Figures
- Figure 1.
HASRA. A, Exploded view of apparatus, showing each part of the assembly. B, Side view of apparatus, showing relative positions of reaching compartment, seed arm, camera, and RFID tag reader for identifying mice. C, Top-down view of front wall, stage motors and range of motion in which a seed could be presented (within black bounding box). D, Representative images taken from wall-facing camera showing a mouse performing each type of event that was classified. Miss, knock-down, and success represented types of attempts to retrieve the pellet using the hand. This perspective was used for scoring data on mouse reaching performance. Location of seed indicated with white arrow in each image.
- Figure 2.
HASRA parameter optimization. A, Proportion of each group showing varying behaviors on day 1 of exposure to the task. B, Mean time per day (minutes) per mouse in which the pellet arm was delivering pellets for each group. This measure of time was used to avoid counting time in which the mouse rapidly entered and exited the HASRA without waiting to actually be delivered at least one pellet. Time in which the animal remained focused on the task long enough to be delivered a pellet more accurately represents, “task engagement.” C, Mean daily qualitative score for each group based on scoring five videos per animal per day. D, Survival curve of percentage of mice that displayed a qualitative score of at least 3 (reaching or licking) by day of training. E, Percentage of successful reaching events based on scoring of 20 events per mouse at each time point. All data are represented as mean ± SEM; * represents a post hoc statistical effect of p < 0.05.
- Figure 3.
Distribution of events by circadian phase. A, Plot of all events for all mice on day 22 (day before stroke) of experiment 2. Each event of a given type is represented by a single black dot. The white portion of each graph represents the light phase of the light cycle (7 A.M. to 7 P.M.), whereas data in the gray portion of the graph represent data from the dark phase (7 P.M. to 7 A.M.). B, Mean percentage of each event type by portion of the light phase. Mean for individual mice are represented by single dots. N = 5159 events, n = 7 mice. All data are represented as mean ± SEM; * represents a post hoc statistical effect of p < 0.05.
- Figure 4.
HASRA sensitivity to lesion-induced impairments. A, Timeline of experiment 2. B, Mean time per day (minutes) per mouse with the pellet arm activated for each group. C, Mean daily qualitative score for each group based on scoring five videos per animal per day. D, Percentage of successful reaching events based on scoring of 20 events per mouse at each time point. The white portion of each graph represents time points before stroke, whereas data in the gray portion of the graph represent poststroke time points. All data are represented as mean ± SEM. N = 7 for all panels; * represents a post hoc statistical effect of p < 0.05.
- Figure 5.
Verification of animal health and lesion induction. A, Mean body weight of all mice throughout experiment 2. B, Mean total infarct volume of all mice receiving stroke. C, Infarct volume of all mice receiving stroke at each anteroposterior coordinate of damage relative to bregma. D, Representative cresyl violet images of lesion in the mouse with the total infarct volume closest to the mean (3.75 mm3). Each image is labeled with its distance anterior to bregma in millimeters. Scale bar = 1 mm. The black lines in panels A–C represent the group mean ± SEM. The gray dots in panels B, C represent the infarct volumes of individual animals. N = 7 for panel A and n = 4 in panels B, C.
Tables
Reaching event type Determinant Total attempts Miss Knock-down Success p value Light phase 715 *100 (14.0%) *335 (46.8%) 280 (39.2%) 0.018 Dark phase 3285 *362 (11.0%) *1705 (51.9%) 1218 (37.1%) Total 4000 462 (11.5%) 2040 (51.0%) 1498 (37.5%) ↵a Total count of each type of reaching event on day 22 of training, split by phase of the light cycle. An attempt was any event where the hand passed through the front slot, resulting in either a miss, knock-down, or successful retrieval of the seed. The number in parentheses shows the percentage of that type of event within a given row. χ2 tests were used to assess differences in the relative distribution of event types across the light cycle (light phase vs dark phase). Cells prefixed by a * had significant differences in their relative distribution between light phases. Overall, 82.1% of reaching events occurred during the dark phase.
Movies
- Movie 1.
Example video showing a mouse engaging with the seed delivery arm to retrieve millet seeds.
Extended Data 1
Archive of assembly instructions, Python/Arduino code, 3D printing STL files, and wiring diagrams. See “homecage assembly manual.pdf” and “README.md” contained in archive for more details. Download Extended Data 1, ZIP file.
In this issue
