John Gibson, who spent 20 years working in psychiatric hospitals until he was sacked for sending sexual images to an adult, befriended a child's social mediaaccount that had been set up by a decoy organisation last February.
Newcastle Crown Court heard during conversations over the Messenger facility, Gibson and the "girl" spoke about "pets and tattoos".
Then, despite being repeatedly told he was talking to a 12-year-old child, the 50-year-old started to talk about sex, said he could be her "first boyfriend", sent a graphic picture and videos and requested the same in return.
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Prosecutor Christopher Rose told the court: "On one occasion he suggested that they get a hotel room in Basingstoke so she could stay with him and he could be her first boyfriend."
The court heard the group behind the fake profile, which was based in the south of England. contacted a similar organisation in the North East and Gibson was lured to a date with an adult, where the police were called.
Mr Rose said: "The defendant collapsed on the floor, complaining of chest pains and he was taken by ambulance.
"During that ambulance journey he admitted messaging a 12-year-old girl on Facebook, saying she wanted to come and meet him and he said no."
Gibson, of Hasting Street, Sunderland, admitted attempting to cause a child under 13 to engage in sexual activity, attempting to engage in sexual communication with a child and attempting to cause a child under 13 to watch a sexual act.
Judge Robert Adams sentenced him to three years and two months behind bars.
Gibson must sign the sex offenders register for life and abide by a sexual harm prevention order for ten years.
Judge Adams told him: "It is very clear you knew and understood she was 12 and you didn't seem to care.
"There is no doubt whatsoever what you were talking about while talking about the hotel."
The court heard Gibson's alcohol abuse was a contributing factor to his offending and he came across the profile by chance "while looking for friends to talk to".
Fiona Lamb, defending, said Gibson has never been in trouble before and has been candid when questioned.
Miss Lamb said: "He accepts, unusually, that the offending behaviour was motivated by sexual gratification." Miss Lamb said Gibson is "at a loss" to explain why he was attracted to a child profile but is willing to address his behaviour.