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Toward Ubiquitous BCIs 365<br />

The best opportunity for increasing effective throughput is through these clever<br />

interface features [3, 80]. This is relatively virgin territory within BCI research.<br />

While improving raw ITR is still important, this task has consumed the bulk <strong>of</strong><br />

BCI research. Many articles about BCIs present novel signal processing tools or<br />

combinations that are applied <strong>of</strong>fline to existing data, <strong>of</strong>ten from a different lab,<br />

and produce a marginal performance improvement in some subjects. ITR could be<br />

improved more by increasing the number <strong>of</strong> mental tasks used either simultaneously<br />

or sequentially, such as with a hybrid BCI, but the main focus should be on interfaces<br />

that can do more with a specific ITR.<br />

Hardware innovations could also improve the effective throughput. For example,<br />

improved amplifiers or sensors that provide a cleaner picture <strong>of</strong> brain activity could<br />

result in fewer errors. Hardware improvements are worthwhile, but the best overall<br />

opportunity for increasing effective throughput remains s<strong>of</strong>tware with clever interface<br />

features that can allow people to convey more useful information with fewer<br />

bits per minute.<br />

2.4 Utility<br />

What can you do with a BCI? Right now, most BCIs control simple monitor-based<br />

applications, such as a speller or cursor with a basic interface and graphics. More<br />

advanced monitor and VR applications are emerging, such as BCIs to control Smart<br />

Homes, immersive games, or virtual environments [20, 41, 55, 64, 72, 74] (see also<br />

chapters “The Graz Brain–Computer Interface” and “The First Commercial Brain–<br />

Computer Interface Environment” in this book). So too are BCIs to control devices<br />

such as orthoses, prostheses, robotic arms, mobile robots, or advanced rehabilitation<br />

robotic systems such as a combined wheelchair and robotic arm [26, 30, 60]. Hence,<br />

both s<strong>of</strong>tware and hardware advances are being made, but BCIs still control a lot<br />

less than mainstream interfaces. BCI utility must and will increase well before BCIs<br />

become ubiquitous.<br />

BCI utility reflects how useful a user considers a BCI. Can the BCI meet a potential<br />

user’s needs or desires? If not, then s/he will probably not use it, even if it is<br />

extremely inexpensive, easy to use, portable, etc. BCI utility is subjective on an<br />

individual level, but can be measured more objectively over larger groups.<br />

A BCI will not seem useful to a user who cannot get it to work. Support availability<br />

is a major issue today. Right now, an expert is typically required to identify<br />

the right components, put them together, customize different parameters, and fix<br />

problems (see chapter “Brain–Computer <strong>Interfaces</strong> for Communication and Control<br />

in Locked-in Patients”). Efforts to reduce dependence on outside help are essential.<br />

A BCI tech support infrastructure must develop to support new and sometimes<br />

frustrated users.<br />

Modern BCIs are relatively inflexible; one BCI can spell or move a cursor or<br />

browse the internet or control a robot arm, but not switch between these applications.<br />

Flexibility could be improved with a Universal Application Interface (UAI)

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