What is Star Trek Next Generation episode where Picard and Dr.
Kreisher have something implanted in their brains so that they know
what the other is thinking?

The episode that you have in mind is Episode 160: Attached


Below you will find references where you mayverify that this is the
correct answer.


Star Trek: The Next Generation - Attached
Episode Number 160 
Synopsis   

?While on a diplomatic mission, Dr. Crusher and Picard are captured
and imprisoned. As a result, they are linked together via a telepathic
device.?

TV Tome
http://www.tvtome.com/tvtome/servlet/GuidePageServlet/showid-137/epid-19146/


Star Trek - The Next Generation, Episode 160: Attached 

?The oft-hinted romantic spark between Captain Picard (Patrick
Stewart) and Dr. Beverly Crusher (Gates McFadden) flares a bit in this
episode written by Nick Sagan, the son of the late scientist Carl
Sagan. Taken hostage by a race called the Prytt--who don't want a
neighboring species, the Kes, to join the Federation--Picard and
Crusher eventually make a break for it but find (because of a Prytt
shackling device) they are attached via their brainwaves. Subjected to
uncontrollable sharing of their thoughts, the two soon discover much
about each other, including an unspoken, mutual attraction.?

Amazon
http://www.amazon.com/exec/obidos/tg/detail/-/B000003K5P/103-3812489-0476630?v=glance


?While transporting to the Kes, Crusher (Gates McFadden) and Picard
(Patrick Stewart) mistakenly end up in a Prytt prison cell where they
are accused of conspiracy and implanted with strange electronic
devices.

After managing to escape, they make their way toward the Kes boarder.
But it's slow going because the devices implanted in their necks allow
them to read each other's most intimate thoughts. Now, as they try to
hide their true feelings from one another, the rest of the crew
struggles to negotiate their freedom.?

http://www.amazon.com/exec/obidos/tg/stores/detail/-/video/B000003K5P/reviews/103-3812489-0476630#b000003k5p2750

Purchase this episode at Amazon
http://www.amazon.com/exec/obidos/tg/detail/-/B000003K5P/103-3812489-0476630?v=glance


Search criteria:
Picard read each others mind Star Trek

I hope you find this helpful! 

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Bobbie7