Brain interfaces as wearables

There are lots of brain devices, and the book has a whole chapter dedicated to them. Most of these brain devices are passive, merely needing to be near the brain to have whatever effect they are meant to have (the chapter discusses in turn: reading from the brain, writing to the brain, telexperience, telepresence, manifesting thought, virtual sex, piloting a spaceship, and playing an addictive game. It’s a good chapter that never got that much love. Check it out.)

This is a composite SketchUp rendering of the shapes of all wearable brain control devices in the survey.

This is a composite rendering of the shapes of most of the wearable brain control devices in the survey. Who can name the “tophat”?

Since the vast majority of these devices are activated by, well, you know, invisible brain waves, the most that can be pulled from them are sartorial– and social-ness of their industrial design. But there are two with genuine state-change interactions of note for interaction designers.

Star Trek: The Next Generation

The eponymous Game of S05E06 is delivered through a wearable headset. It is a thin band that arcs over the head from ear to ear, with two extensions out in front of the face that project visuals into the wearer’s eyes.

STTNG The Game-02

The only physical interaction with the device is activation, which is accomplished by depressing a momentary button located at the top of one of the temples. It’s a nice placement since the temple affords placing a thumb beneath it to provide a brace against which a forefinger can push the button. And even if you didn’t want to brace with the thumb, the friction of the arc across the head provides enough resistance on its own to keep the thing in place against the pressure. Simple, but notable. Contrast this with the buttons on the wearable control panels that are sometimes quite awkward to press into skin.

Minority Report (2002)

The second is the Halo coercion device from Minority Report. This is barely worth mentioning, since the interaction is by the PreCrime cop, and it is only to extend it from a compact shape to one suitable for placing on a PreCriminal’s head. Push the button and pop! it opens. While it’s actually being worn there is no interacting with it…or much of anything, really.



Head: Y U No house interactions?

There is a solid physiological reason why the head isn’t a common place for interactions, and that’s that raising the hands above the heart requires a small bit of cardiac effort, and wouldn’t be suitable for frequent interactions simply because over time it would add up to work. Google Glass faced similar challenges, and my guess is that’s why it uses a blended interface of voice, head gestures, and a few manual gestures. Relying on purely manual interactions would violate the wearable principle of apposite I/O.

At least as far as sci-fi is telling us, the head is not often a fitting place for manual interactions.

Precrime forearm-comm


Though most everyone in the audience left Minority Report with the precrime scrubber interface burned into their minds (see Chapter 5 of the book for more on that interface), the film was loaded with lots of other interfaces to consider, not the least of which were the wearable devices.

Precrime forearm devices

These devices are worn when Anderton is in his field uniform while on duty, and are built into the material across the left forearm. On the anterior side just at the wrist is a microphone for communications with dispatch and other officers. By simply raising that side of his forearm near his mouth, Anderton opens the channel for communication. (See the image above.)


There is also a basic circular display in the middle of the posterior left forearm that displays a countdown for the current mission: The time remaining before the crime that was predicted to occur should take place. The text is large white characters against a dark background. Although the translucency provides some visual challenge to the noisy background of the watch (what is that in there, a Joule heating coil?), the jump-cut transitions of the seconds ticking by commands the user’s visual attention.

On the anterior forearm there are two visual output devices: one rectangular perpetrator information (and general display?) and one amber-colored circular one we never see up close. In the beginning of the film Anderton has a man pinned to the ground and scans his eyes with a handheld Eyedentiscan device. Through retinal biometrics, the pre-offender’s identity is confirmed and sent to the rectangular display, where Anderton can confirm that the man is a citizen named Howard Marks.

Wearable analysis

Checking these devices against the criteria established in the combadge writeup, it fares well. This is partially because it builds on a century of product evolution for the wristwatch.

It is sartorial, bearing displays that lay flat against the skin connected to soft parts that hold them in place.

They are social, being in a location other people are used to seeing similar technology.

It is easy to access and use for being along the forearm. Placing different kinds of information at different spots of the body means the officer can count on body memory to access particular data, e.g. Perp info is anterior middle forearm. That saves him the cognitive load of managing modes on the device.

The display size for this rectangle is smallish considering the amount of data being displayed, but being on the forearm means that Anderton can adjust its apparent size by bringing it closer or farther from his face. (Though we see no evidence of this in the film, it would be cool if the amount of information changed based on distance-to-the-observer’s face. Writing that distanceFromFace() algorithm might be tricky though.)

There might be some question about accidental activation, since Anderton could be shooting the breeze with his buddies while scratching his nose and mistakenly send a dirty joke to a dispatcher, but this seems like an unlikely and uncommon enough occurrence to simply not worry about it.

Using voice as the input is cinemagenic, but especially in his line of work a subvocalization input would keep him more quiet—and therefore safer— in the field. Still, voice inputs are fast and intuitive, making for fairly apposite I/O. Ideally he might have some haptic augmentation of the countdown, and audio augmentation of the info so Anderton wouldn’t have to pull his arm and attention away from the perpetrator, but as long as the information is glanceable and Anderton is merely confirming data (rather than new information), recognition is a fast enough cognitive process that this isn’t too much of a problem.

All in all, not bad for a “throwaway” wearable technology.