Hello Sarah, you asked to chrono "Explain please. Especially the computer that reads your thoughts - how is that done."
I can tell you that in 1993/94 I did a art exhibit called 'dream machines'.
I used a scan brain, the EEG of my scan brain, was capturing brain waves, real time,
with a Xobject that I wrote I could communicated with my computer,(was a MAC II)
In the computer I used a sequencer, which was receiving and Interpreting the brain waves
(by midi signal) and from the output of the computer I linked a robotics interface.
the system was inside my sculpture, it was working well, and independently of your brain condition,
corresponding to relaxation, concentration or high brain activities, the sequencer of the computer was giving some feedback on screen.
It was also communicating with an external device: a robotic interface, giving
(in regards of your brain activities range), order such as xon xoff
and gradually for music, lights, animated sculpture and image video projection.
then it was a re-lecture took by the scan brain for interacting.
it was far away from a computer who reads directly "thoughts" but once we will
perhaps be able to interpreting the thoughts by reading "images thoughts" of
our brain, with a new device, we will then be able to send it to a computer for interaction, rendition n implementation.
a temporel