Recent neuroscience and preclinical research on recording signals from targeted brain microcircuits as neural populations with single neuron resolution has considerably advanced our ability to understand the role of dynamical brain states that guide e.g.motor planning and action in non-human primates, to the emerging field of neural prosthetics for disabled human subjects demonstrated e.g.in controlling a robotic arm and hand.These advances where recordings are performed via intracortical or subdural multielectrode arrays have revealed much promise for high performance Brain/Machine or Brain/Computer Interfaces (BMIs and BCIs).This, in turn, has created a quest for compact wearabale or implantable electronic microsystems that can record neurophysiological signals from large numbers of single neurons across a wide range of spatial and temporal scales.Most present recording systems require a wired percutaneous connection between the head implanted electrodes and external recording instrumentation.However, any percutaneous cabling considerably restricts the subjects mobility, present a liability for infection, and cause potential contamination of the weak electronic signals due to external noise/interference.Hence, creating a wireless, implantable system that eliminates the need for percutaneous connection offers great advantages.Such a wireless system, which should reside within the bodys protective skin envelope, must fulfill multiple stringent requirements for neuroscientific, clinical, and engineering considerations, respectively.From the implantable systems point of view, challenges include ultralow-power integrated circuit design, hermetically sealed device packaging, large bandwidth wireless telemetric capability (50 Mb/sec and beyond), and compatibility with surgical implantation procedures.We present here a fully implantable, hermetically sealed, wireless neural recording system which has been validated as chronic implant in freely moving monkeys and pigs, and show how received neural signals can be deciphered as brain state trajectories while animals were engaged in specific activity.The system interconnects a 10× 10 silicon-based intracortical microelectrode array neural sensor to the hermetically sealed titanium enclosure that houses the active electronics.In terms of engineering performance, the system features 100 wideband (0.1Hz~7.8kHz) neural recording channels witheach channel capable of recording action potentials and local field potentials from targeted cortical circuitry.Supporting elements in the implant include a medical grade 200mAh rechargeable Li-ion battery charged by 2MHz inductive link, and both 3.2/3.8GHz FSK and 850nm IR for data telemetry.