Do androids, as sci-? novelist Philip K.
Dick asked, really dream of electric
sheep? The purpose and meaning of
dreams have long been debated. Now
scientists are getting closer to decipher-
ing what humans see as they sleep—and
how a robot can simulate it.
In 2013 neuroscientist Yukiyasu Ka-
mitani had test subjects take hundreds of
brief naps in an MRI machine, repeatedly
waking them so they could describe their
dreams. Kamitani had already isolated
the unique brain patterns for certain ob-
jects he’d shown subjects while awake.
Their brains were scanned for those pat-
terns as they napped, and a computer
program automatically turned the basic
contents of their dreams into short videos.
The study found these were 70 percent
accurate compared with what subjects
remembered of their real dreams.
Two years later Google engineers also
captured the dreamlike images of a com-
puter. They fed millions of images into
a brain-inspired computer algorithm—a
network of arti?cial neurons—to study
how it learned to identify objects. Then
they put it through DeepDream, a pro-
gram that enables the network to build
its own algorithm-fueled dreamscape by
nding shapes in an image of random vi-
sual noise, like the static on an old TV. The
computer generated a psychedelic scene
from its machine-learned knowledge. As
in a dream, previously seen images were
recon?gured into new patterns.
It won’t be possible to produce a pre-
cise recording of human dreams until
scientists discover how dreams originate
in the brain, says Jack Gallant, a professor
of psychology at UC Berkeley—or they
build an encyclopedia of brain activity
that corresponds to every thought. He
likens it to building a language transla-
tion program: “You have a language but
nothing it references to.”
