Schölvinck, M. L. | bioRxiv Science

bioRxiv2024

Sharing the Spotlight: Uncovering common attentional dynamics across species

Sustained attention is a key underlying process to many natural behaviours that are shared by multiple species. Yet the way it is commonly studied in a lab context precludes any meaningful cross-species comparisons. Here, we engaged mice, monkeys, and humans in the exact same, natural perceptual decision task in a VR environment. We captured their behaviour into several parameters along the speed/accuracy axes along which sustained attention is classically defined, and used HMMs to infer four attentional states. We show that the dynamics of these states, both in terms of their durations as well as the transitions between them, are much more similar between the species than might have been expected. Moreover, attentional state fluctuations seem to be internally generated. The task and analyses developed here represent a new approach to compare sustained attention across species in an objective, data-driven way.

animal behavior and cognition↗

bioRxiv2022

Modular, cement-free, customized headpost and connector-chamber implants for macaques

BackgroundNeurophysiological studies with awake macaques typically require chronic cranial implants. Headpost and connector-chamber implants are used to allow head stabilization and to house connectors of chronically implanted electrodes, respectively. New MethodWe present long- lasting, modular, cement-free headpost implants made of titanium that consist of two pieces: a baseplate and a top part. The baseplate is implanted first, covered by muscle and skin and allowed to heal and osseointegrate for several weeks to months. The percutaneous part is added in a second, brief surgery. Using a punch tool, a perfectly round skin cut is achieved providing a tight fit around the implant without any sutures. We describe the design, planning and production of manually bent and CNC-milled baseplates. We also developed a remote headposting technique that increases handling safety. Finally, we present a modular, footless connector chamber that is implanted in a similar two- step approach and achieves a minimized footprint on the skull. ResultsTwelve adult male macaques were successfully implanted with a headpost and one with the connector chamber. To date, we report no implant failure, great headpost stability and implant condition, in four cases even more than 9 years post-implantation. Comparison with Existing MethodsThe methods presented here build on several related previous methods and provide additional refinements to further increase implant longevity and handling safety. ConclusionsOptimized implants can remain stable and healthy for at least 9 years and thereby exceed the typical experiment durations. This minimizes implant-related complications and corrective surgeries and thereby significantly improves animal welfare. HighlightsO_LILong-lasting titanium implants for non-human primates C_LIO_LIRefined implantation techniques that reduce post-operative complications C_LIO_LIMinimized, footless connector chamber to house connectors of chronic arrays C_LIO_LITwelve adult male macaques were implanted with long-lasting headpost implants C_LIO_LIHeadpost implants so far without failure and with longevity up to > 9 years C_LI

neuroscience↗