Multichannel micromanipulator and chamber system for recording multineuronal activity in alert, non-human primates

We describe the design and performance of an electromechanical system for conducting multineuron recording experiments in alert non-human primates. The system is based on a simple design, consisting of a microdrive, control electronics, software, and a unique type of recording chamber. The microdrive consists of an aluminum frame, a set of eight linear actuators driven by computer-controlled miniature stepping motors, and two printed circuit boards (PCBs) that provide connectivity to the electrodes and the control electronics. The control circuitry is structured around an Atmel RISC-based microcontroller, which sends commands to as many as eight motor control cards, each capable of controlling eight motors. The microcontroller is programmed in C and uses serial communication to interface with a host computer. The graphical user interface for sending commands is written in C and runs on a conventional personal computer. The recording chamber is low in profile, mounts within a circular craniotomy, and incorporates a removable internal sleeve. A replaceable Sylastic membrane can be stretched across the bottom opening of the sleeve to provide a watertight seal between the cranial cavity and the external environment. This greatly reduces the susceptibility to infection, nearly eliminates the need for routine cleaning, and permits repeated introduction of electrodes into the brain at the same sites while maintaining the watertight seal. The system is reliable, easy to use, and has several advantages over other commercially available systems with similar capabilities.