<s>
Silent	B-Application
speech	I-Application
interface	I-Application
is	O
a	O
device	O
that	O
allows	O
speech	O
communication	O
without	O
using	O
the	O
sound	O
made	O
when	O
people	O
vocalize	O
their	O
speech	O
sounds	O
.	O
</s>
<s>
It	O
works	O
by	O
the	O
computer	O
identifying	O
the	O
phonemes	B-Language
that	O
an	O
individual	O
pronounces	O
from	O
nonauditory	O
sources	O
of	O
information	O
about	O
their	O
speech	O
movements	O
.	O
</s>
<s>
These	O
are	O
then	O
used	O
to	O
recreate	O
the	O
speech	O
using	O
speech	B-Application
synthesis	I-Application
.	O
</s>
<s>
Silent	B-Application
speech	I-Application
interface	I-Application
systems	O
have	O
been	O
created	O
using	O
ultrasound	B-Application
and	O
optical	O
camera	O
input	O
of	O
tongue	O
and	O
lip	O
movements	O
.	O
</s>
<s>
They	O
have	O
also	O
been	O
created	O
as	O
a	O
brain	B-Application
–	I-Application
computer	I-Application
interface	I-Application
using	O
brain	O
activity	O
in	O
the	O
motor	O
cortex	O
obtained	O
from	O
intracortical	O
microelectrodes	O
.	O
</s>
<s>
The	O
feasibility	O
of	O
using	O
silent	B-Application
speech	I-Application
interfaces	I-Application
for	O
practical	O
communication	O
has	O
since	O
then	O
been	O
shown	O
.	O
</s>
<s>
A	O
2019	O
study	O
by	O
MIT	O
Researcher	O
,	O
Arnav	O
Kapur	O
,	O
has	O
developed	O
a	O
Silent	B-Application
Speech	I-Application
Interface	I-Application
,	O
AlterEgo	O
,	O
which	O
effectively	O
serves	O
as	O
a	O
brain-computer	B-Application
interface	I-Application
and	O
requires	O
only	O
subtle	O
stimulation	O
of	O
the	O
speech	O
muscles	O
to	O
operate	O
.	O
</s>
<s>
A	O
by	O
Varun	O
Chandrashekhar	O
also	O
involves	O
the	O
development	O
of	O
a	O
Silent	B-Application
Speech	I-Application
Interface	I-Application
,	O
SpeakUp	O
.	O
</s>
<s>
In	O
this	O
,	O
HAL	B-General_Concept
9000	I-General_Concept
,	O
a	O
computer	O
controlling	O
spaceship	O
Discovery	O
One	O
,	O
bound	O
for	O
Jupiter	O
,	O
discovers	O
a	O
plot	O
to	O
deactivate	O
it	O
by	O
the	O
mission	O
astronauts	O
Dave	O
Bowman	O
and	O
Frank	O
Poole	O
through	O
lip	O
reading	O
their	O
conversations	O
.	O
</s>
