OpenStride: an inexpensive, open-source force plate actometry system for quantification of rodent motor activity and behaviour.

Force plate actometry (FPA) enables quantitative assessment of rodent motor and behavioural activity. Through tracking centre of mass at high temporal and spatial resolution, FPA can directly quantify motor performance and various behaviours in the context of operator-independent, naturalistic movement. Previously designed systems have been expensive and non-customisable, and they are no longer commercially available. We designed OpenStride, an open-source FPA system consisting of both hardware and software. Our system was designed to be able to be constructed with standard tools worldwide at a cost of ~$550 USD, with modifiable hardware files, modular software, and support for both Mac and Windows operating systems. Required tools include 3D printing and acrylic laser cutting. OpenStride reliably tracks position within a 30 ⋅ 30 cm2 environment. Based on these positional data, OpenStride currently quantifies tremor, ataxia, distance, velocity, low-mobility bouts, and centre-vs.-margin time, with potential to expand to additional analyses. OpenStride is intended to provide a valuable tool for high-throughput, inexpensive study of motor and behavioural function and dysfunction. Software and hardware files have been freely disseminated online via GitHub (OpenStrideNeuro) to enable others to construct and utilise the OpenStride system.