Messin’ with Brain Cells
For decades, sci-fi movies and TV shows have portrayed characters whose brains have been erased or
reprogrammed by evil-doers. This fictitious process is so
common that it doesn’t particularly terrify most of us
anymore. Maybe it should now, because UC Berkeley
( www.berkeley.edu) neuroscientists are getting closer to
making it a reality.
Under development is a system that uses holographic
projection to activate or deactivate brain activity, thereby
allowing it to “edit the sensations we feel, paste in our
brain pictures that we never saw, cut out unwanted pain,
or insert nonexistent scents into memory.”
Recently, a chunk of mouse brain was treated with a
protein that when hit with a flash of light turns the cell on
and creates a spike of activity. To function properly, the
system needs enough accuracy to “shoot the very
specific sets of neurons you want to activate and do it at
the characteristic scale and the speed at which they
normally work.” Apparently, they have achieved that.
The researchers have already tested the prototype on
mice as they walk on a treadmill, acting on the touch,
So, how long until they are able to work with live
human brains? Who knows? Maybe they already can.
Maybe they already have.
Are you absolutely certain you were at the Snake Pit
Bar and Grill last night? ▲
Say No More
You may not have thought about it, but when engaged in silent reading, you think the words as you read them and
hear them in your mind. This is known as “subvocalization,”
and the phenomenon has been under consideration since
the mid 1800s. In 1899, a researcher named Curtis
concluded that silent reading was, in fact, the only mental
activity that caused significant movements of the larynx.
Half a century later, A. W. Edfeldt devised an electrical
instrument that could record this movement. His device was
too primitive to correlate movements with specific words,
but he did conclude that silent speech reinforces learning
and is therefore a good thing.
Other researchers have come to the opposite
conclusion: that subvocalization should be minimized. After
all, if you have to subvocalize everything you read, you can’t
read any faster than you can speak (about 150 to 250 words
per minute). It’s therefore widely considered to be a
hindrance to learning, and speed readers are trained to
avoid it as much as possible.
Researchers at the MIT Media Lab
( www.media.mit.edu) have now created a wearable device
that picks up neuromuscular signals in the face and jaw and
feeds them to a machine-learning system that can associate
the signals with
specific words. The
includes a pair of
vibrations through the
face bones to the
inner ear, bypassing
the ear canal
In one experiment, subjects used the system to report
opponents’ moves in a chess game and receive a
computer’s recommended moves, all soundlessly. In
another, 10 subjects used the system to execute
computations, and it turned out to be about 92 percent
accurate. Accuracy should improve as data about more
complicated conversations is collected.
Researchers speculate that the system could be valuable
in both extremely noisy environments and one where
silence is mandatory (e.g., special ops). It could also allow
disabled people who can’t speak normally to communicate
with others. ▲
■ A sample hologram with 50 randomly distributed
■ BY JEFF ECKERT TECHKNOWLEDGEY 2018
■ MIT’s AlterEgo device allows silent speech.
8 July/August 2018