Design of a head fixation device for experiments in behaving monkeys

3D printing and modelling of customized implants and surgical guides for non-human primates

“…An interface consisting of either electrical contact points or a wireless transceiver unit is mounted on the pedestal, providing a connection to external equipment. Furthermore, when performing acute recordings, or when a task necessitates the spatial stabilization of images on the retina, fixation of the head is commonly achieved using a single-piece, screw-mounted head post (Adams et al, 2007), or an equivalent device with multiple contact points on the skull (Pigarev et al, 1997, Isoda et al, 2005). …”

Non-invasive primate head restraint using thermoplastic masks

“…The majority of these devices involve implantation of screws or bolts into the subject’s skull, as well as the attachment of additional hardware – most commonly a head-post – that protrudes from the head and can be attached to the primate chair during experimental sessions (Adams et al, 2007; Betelak et al, 2001; Evarts, 1968; Foeller and Tychsen, 2002; Porter et al, 1971). An alternative technique is the halo device, in which an aluminum ring surrounds the skull and is attached by several skull pins which require a smaller amount of skin to be removed and shallower penetrations into the skull (Friendlich, 1973; Isoda et al, 2005; Pigarev et al, 1997, 2009). …”

A non-invasive head-holding device for chronic neural recordings in awake behaving monkeys

“…Most of these experiments have been performed in monkeys that were head-fixed, as most recording systems depend critically on adequate fixation of the animal’s head so that electrical activity from single and multiple units can be recorded without noise artifact and with a constant relationship of the subject’s head position to experimental stimuli and monitoring equipment. For this purpose, series of methods for head holding have been developed (Adams et al, 2007; Davis et al, 2009; Evarts, 1968; Isoda et al, 2005; Pigarev et al, 2009; Srihasam et al, 2010), most of which, following the pioneering work of Evarts, require head-restraint bolts to be implanted into the skull (Adams et al, 2007; Davis et al, 2009; Evarts, 1968). These methods all allowed excellent stabilization of the subject’s head, but with prolonged times following implantation, head-bolt systems become increasingly at risk for intracranial infection or necrosis and softening of bone around the head post, where the principal torques are applied during experimental sessions.…”

“…This situation can lead to instability and ultimately failure of the implanted devices. In an attempt to solve such problems, less invasive methods without bolts screwed on the skull have been developed in some studies (Isoda et al, 2005; Pigarev et al, 2009). They achieved rigid head fixation, but even with those methods, small incisions of the skin are still necessary at the time of installation.…”