An automated task for the training and assessment of distal forelimb function in a mouse model of ischemic stroke

Abstract

Background Behavioral models relevant to stroke research seek to capture important aspects of motor skill typically impaired in human patients, such as coordination of distal musculature. Such models may focus on mice since many genetic tools are available for use only in that species, and since the training and behavioral demands of mice can differ from rats even for superficially similar behavioral readouts. However, current mouse tests are time consuming to train and score, especially in a manner producing continuous quantification. An automated assay of mouse forelimb function may provide advantages for quantification and speed, and may be useful for many applications including stroke research. New Method We present an automated assay of distal forelimb function. In this task, mice reach forward, grip and pull an isometric handle with a prescribed force. The apparatus partially automates the training process so that mice can be trained quickly and simultaneously. Results Using this apparatus, it is possible to measure long-lasting impairment in success rate, force pulled, latency to pull, and latency to success up to 22 weeks following photothrombotic cortical strokes in mice. Comparison with Existing Method(s) This assessment measures forelimb function as do pellet reach tasks, however it utilizes a different motion and provides automatic measures that can ease and augment the research process. Conclusions This high-throughput behavioral assay can detect long-lasting motor impairments, eliminates the need for subjective scoring, and produces a rich, continuous data set from which many aspects of the reach and grasp motion can be automatically extracted.

The supination assessment task: An automated method for quantifying forelimb rotational function in rats

“…Recently, several automated methods of evaluating motor function in the rat have been developed (Hays et al 2013a, 2013b; Poddar et al 2013; Jarrahi et al 2015; Kawai et al 2015; Sloan et al 2015; Wong et al 2015; Becker et al 2016). Automation of motor assessments obviates many limitations of traditional assessments such as single pellet retrieval, permitting high-throughput testing and potentially decreasing the cost and time of running experiments.…”

Cortical Transplantation of Brain‐Mimetic Glycosaminoglycan Scaffolds and Neural Progenitor Cells Promotes Vascular Regeneration and Functional Recovery after Ischemic Stroke in Mice

“…Mice treated with CS‐A + NPCs showed a significantly improved time to sticker removal 1 week after transplantation (Figure 3B). Due to high rates of functional recovery in the corner and adhesive removal tests by 3 weeks after induction of mini‐strokes to the sensorimotor cortex (Figure 3A,B), we also tested forepaw motor function using the volitional isometric pull test, which more readily detects subtle defects in forepaw motor function and dexterity . 2 weeks after transplantation, mice treated with CS‐A + NPC showed improved pull strength compared to the sham treatment group and superior hit rates compared to the cellular control group (Figure 3C,D).…”

Stimulated grip strength measurement: Validation of a novel method for functional assessment

“…It can be difficult at times to coax the animals to participate in vGST, making the testing process both tedious and time‐consuming. It should be noted that there are modifications to vGST that incorporate more elaborate training protocols and rewards systems in an effort to limit this behavioral variability . However, these more intensive methods are still subject to behavioral variability, and it is not clear that they provide the same degree of reliability that can be achieved with direct nerve stimulation.…”

“…It should be noted that there are modifications to vGST that incorporate more elaborate training protocols and rewards systems in an effort to limit this behavioral variability. [21][22][23] However, these more intensive methods are still subject to behavioral variability, and it is not clear that they provide the same degree of reliability that can be achieved with direct nerve stimulation. In addition to behavioral variability, vGST is also affected by variability introduced by the method in which the test is administered, given the inability to standardize the speed and vector of distraction.…”