match this word in username and this domain

I'm on a humor list that seems to come through with a variety of names.

Each of the names has the word "humour" (spelled that way... could  
be first word, last word, or in middle) in the username and comes  
from SOME machine at "synapse.net"

I tried to match it this way:

:0
* ^From(_dot_)*humour*(_at_)*synapse\(_dot_)net

but that gave this message in the log:

procmail: No match on "^From(_dot_)*humour*(_at_)*synapse\(_dot_)net"

on this message

        From humour-list-request(_at_)conductor(_dot_)synapse(_dot_)net

I tried other variants but I'm obviously doing something wrong.

thanks
TjL