IEEE Technology and Society Magazine - June 2015 - 38

The basic idea of the BCI Anonymizer is to pre-process neural signals, before they are stored and transmitted, in order
to remove all information except specific intended BCI
commands. Unintended information leakage is prevented
by never transmitting and never storing raw neural signals
and any signal components that are not explicitly needed
for the purpose of BCI communication and control.
The BCI Anonymizer can be realized either in hardware or in software, as a part of the user's BCI device,
but not as part of any external network or computational
platform. It thus acts as a secured and trusted software or
hardware subsystem that takes the raw neural signal and
decomposes it to specific components. Upon request,
instead of the complete recorded neural signal, the BCI
Anonymizer provides a BCI application only with a needed subset of requested signal components. A block diagram of a BCI system with the proposed BCI Anonymizer
component is depicted in Fig. 3. A critical task in the
development of this approach is the development of fast
and accurate signal processing tools for real time decomposition of neural signals.
The described approach is similar to the approaches
taken in smartphone security, where an attacker, using
a malicious smartphone app, can attempt to access
a user's private identifying information (PII), such as a
user's location or address book entries. In the smartphone industry, such attacks on a user's privacy are
typically prevented by limiting access to the phone's
operating system and a user's PII. In other words, an

application only has access to a limited subset of PII data
and operating system states and functionalities. (For
examples of current prevention and mitigation strategies,
please see, e.g., [44], [45]). Neural signals, acquired by BCI
recording electrodes, have a similar role as a user's smartphone PII data, in that they contain information beyond
the intended information.

Address BCI Privacy Threats
in Early Design Phase
Privacy and security threats arising from BCI-enabled
technologies may not pose a critical concern at this
moment, given the fairly limited deployment of BCI systems outside of research and medical communities. We
believe, however, that the right time to address these
issues is now, and we propose that methods to prevent
and mitigate BCI-enabled privacy and security threats
should be developed in the early design phase, and
embedded throughout the entire life of the technology.
We view the development of these prevention and
mitigation tools as an interdisciplinary effort, involving
neuroscientists, neural engineers, ethicists, as well as
legal, privacy, and security experts. This article represents
an initial step towards facilitating the necessary interdisciplinary discussion and starting the effort to make BCI
systems inherently privacy preserving and secure. We are
currently examining the best legal and policy infrastructure BCIs, and experimenting with engineering approaches that could lead to best privacy enhancing practices.

Enhanced Privacy BCI System

Signal
Acquisition

Digitized
Signal

Legitimate
Request for Data
BCI
Anonymizer

BCI
Response

Malicious
Request for Data

Legitimate
Application-Specific
Interpretation

Malicious Data
Interpretation

Extracted
Private Data

Application

Secured and Trusted Part of a BCI System
Legitimate Part of a BCI System
Malicious Part of a BCI System
Figure 3. A simplified diagram of a BCI with the BCI Anonymizer subsystem. A legitimate interpretation component (denoted as light

orange block in the diagram) requests data and receives response from the BCI Anonymizer (denoted as light blue block in the diagram).
Malicious components, added by the attacker (denoted as red block in the diagram), may request data, but will not receive a response from the
BCI Anonymizer. In addition, an attacker cannot access states and functionality of BCI Anonymizer component.

IEEE Technology and Society Magazine

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june 2015

Table of Contents for the Digital Edition of IEEE Technology and Society Magazine - June 2015