I believe the episode goes like this, Riker is 30 years in the future. He
has had a full life(including a son).  He soon realizes this is just a
Romulan trick to extract information from him.  THEN later he realizes his
"son" is just a lonely being with great mental ability had attempted to
create a reality for Riker to keep the boy company.  But of course Riker is
too smart.
 
 
Also, a different Star Trek Next Gen episode:
This one also with Riker, He is sent down with an away team to survey a
planet.  The entire team injestes some kind of gas.  They have to beam them
all out of there.  When Riker revives he learns that it is now 30 years
later and that he is suffering some kind of memory loss.
Anyway, he relizes that it is not real and then thrown into another
"reality" as well.  (I don't remember the name of this episode, maybe
somebody else can help out).
 
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John P
 
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