Documents / Report

Defense Intelligence Reference Document Technological Approaches To Controlling

Defense Intelligence Agency · 36 pages · text from the file's own layer

This Defense Intelligence Reference Document from the Defense Intelligence Agency, dated 23 March 2010, was produced under the Advanced Aerospace Weapon System Applications (AAWSA) Program. It surveys invasive and noninvasive brain-machine interface technologies for controlling external devices without limb-operated interfaces. The technologies covered include EEG, MEG, fMRI, NIRS, and implanted electrode arrays. It concludes that noninvasive electrical monitoring is the most promising near-term approach. In the long term, it favors invasive single-neuron cortical connections that use optical stimulation or chip-based arrays.

  • p. 5 UNCLASSIFIED/)' Pett :SPPll!ltllt '11815 .,.LY Technological Approaches to Controlling External Devices in the Absence of…
  • p. 8 …Neurons require some time to reset between firings, nominally the duration of the pulse for that…
  • p. 10 UNCLASSIFIED/ ,erg A gffllil.t.L '1181!! 8HLY The brain activity mentioned above is a complex…
  • p. 13 …The response time to execute a command using these systems is measured in seconds. The results…
  • p. 14 …application, the fact that 100 IT is about 100 million times smaller than the Earth's…
  • p. 15 …In current MRis, these gradient fields are produced with electromagnets, and the series of time-dependent…
  • p. 18 …prior to implantation, and then the tasks are repeated multiple times while muscle action and cortical…
  • p. 19 …the movement control algorithm is similar to a population vector in that movement at each time…
  • p. 20 UNCLASSIFIED/,'P81il 8PPll!ltllt ~81!! 8HLV Japan in real time. Using visual feedback to the monkey…
  • p. 21 …employed to allow for real-time bidirectional interface with the nervous system. After several modifications, Fetz…
  • p. 22 …understand the brain, its regions of activity and how those area correlate to real time stimulation…
  • p. 25 …FOV=60x60mrn 7 • Experiment time=512 s. (B) (Top) Microelectrode array used in the study. (Bottom…
  • p. 28 …Movement times to target were on the order of 1-2 seconds with up to 75…
  • p. 29 …This trial lasted 3 months before the physical connection between the nerve and the microarray deteriorated…
  • p. 31 …Also beneficial to reaction time is the combined EMG EEG devices mentioned above since the pathways…
  • p. 32 …Proof of principle studies in this technology could emerge at any time, and given the demonstrated…
  • p. 34 …time. J Cogn Neurosci 2002 Nov 15; 14(8): 1200-14. " Hatsopoulos NG, Donoghue JP. The…
  • p. 36 …Targeted muscle reinnervation for real- time myoelectric control of multifunction artificial arms. JAMA 2009 Feb 11…
UNCLASSIFIED/;'P81il 8PPll!ltllt ~81!! 8HLV
of a spiking train to trigger a switch, or as complex as decoding signal from noise
utilizing a 300-channel EEG cap.
~-------------------------,
: Additional sensory :
I ____I ____________________ I
Input
interface
Brain
l Output
Output signal
interface processing
Components of a
Closed-loop BMI
Control System
Input
signal
processing
External
Device
Figure 2. The General Layout of a Closed-Loop Control Interlace. The input and output interfaces can attach
to read or affect activity of cerebral or peripheral neurons. Additional sensory feedback channels such as visual
displays, audio tones, or haptic feedback are possible. In some system designs, especially noninvasive types, these
sensory feedback channels replace stimulation inputs. In an open-loop interface, either the input or output signal
paths are absent.
One consideration in developing a BMI control system is the utility of the application:
does it make sense to directly tie these controls to neural activity? The bulk of research
in direct neural interfaces is toward the goal of restoring mechanical capabilities to
those individuals who have either lost limbs or lost control of limbs through central
nervous system injury or disease. In these cases it is of obvious utility to produce a
system that moves a cursor across screen to select an item over the course of several
seconds; however, for a healthy individual, it is far more practical to execute a hand
movement to control a mechanical device4 to achieve the same goal.
An exception to consider is the case of applications where the subject's hands or feet
are already occupied with other essential tasks in the overall application. A research
question for any such application is whether training a subject to utilize a BMI is
advantageous over a more complex mechanical interface. Furthermore, whether
training on a new BMI affects learning/retaining proficiency with similar BMis is an
additional concern.
Moreover, for any BMI, one can quantitatively describe the information transfer in
controlling the magnitude of human motor action (Reference 12). Since the advent of
digital control of external devices, this information is expressed in equivalent bits per
4 Mechanical device as used here represents any limb-operated interface, such as a mouse or touchscreen.
5
UNCLASSIFIED/ ;CFQA: QFFIGIPk IP&'i Qllk¥

Not linked to a story yet.

About this file

Report, from the dia collection. The PDF is mirrored here; the original link is under it. 36 pages are in the text index: search them above, or from the library's search.