Defense Intelligence Reference Document Technological Approaches To Controlling

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Japan in real time. Using visual feedback to the monkey via live streaming video, the humanoid robot in Japan was
shown to execute locomotion-like movements in a similar manner as the monkey. (Reference 43)
An example of a closed loop peripheral system is the creation of the humanoid robot
called CB-i (Computational Brain Interface). This system is illustrated in Figure 4. In a
recent experiment, CB-i successfully mimicked the physical actions being performed by
a monkey that was positioned in a remote location (Reference 43).
MEMS, ECOG, AND PSOC CIRCUITRY
To address the issue of signal interface between the biological and physical systems,
development has focused on hybrid devices that are created by fusing together
biomolecules, cells, and other tissues, with innovative micro-size current sensors using
Micro Electro Mechanical Systems (MEMS). These systems often employ the use of
biomaterials and functional high polymer materials that enable the device to sense
information about the human body and the environment with greater speed and
sensitivity than conventional metallic sensors. These devices are built from materials
and mechanisms that are compatible with the human body, and they are proving to be
powerful tools for interfacing between the human body and machines.
The emergence of MEMS biotechnology has motivated various strategies to detect
electrical signals generated from a stimulated region within the brain into a captured
electrical response that is translated to a machine interface. One advantage of these
devices is that the fusing of biological to physical circuitry is performed external to the
body and the interface connection of the implants is thus biological to biological. This
avoids a natural reaction of the nervous system to form scar tissue around penetrating
chronic physical probes. 18 Scar tissue leads to degradation of proximal signal transfer
over time. These neural-tissue encapsulated chips offer significant advantages over
other technologies because of their ability to be rapidly integrated into the biological
environment.
Noninvasive EEG platforms often utilize a cap that covers the skull and reads the
electrical signals generated from the brain on the surface of the skin atop the head.
However, a technical limitation in the bandwidth of EEG-based methods often provides
low information rates. Currently EEG methods are limited to 20-30 bits/min(< 0.5
bits/s). This drawback has prompted the use of a more accurate and speedy recording
method based on invasive techniques such as the electrocorticogram (ECoG), where
electrode arrays are placed on top of the cortex, but electrode penetration into brain
tissue is minimal. ECoGs have become synonymous with the pre-surgical monitoring of
epileptic seizure foci (Reference 45). Valuable insights can be gained by combining both
invasive and noninvasive schemes. For example, combining functional MRI (fMRI) and
intracortical recording has yielded important information about metabolic mechanisms
that are most highly correlated with recorded neural activity. Microelectric neurochip
developments seek to combine signal sensing and processing for bidirectional BMI
systems.
Studies in the feasibility of using adaptive input-output models for reconstructing hand
trajectories have recently been published. These studies have focused on the
18 Chronic devices are intended for long-duration implant, in contrast with acute implanted devices, which are
utilized for a short duration and then removed. Formation of scar tissue is dependent on the material used for the
electrodes.
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