The shadows of barred windows make the Buenos Aires psychiatric hospital seem especially soulless, but then the syncopated beats of tango music fill the air.
For a handful of residents at the Borda hospital, the daily shuffle in line for medication has given way to the sensual steps of Argentina's classic dance.
The twice-monthly class is called "We are all crazy about tango."
"People with mental illnesses tend to be passive receptors, but in tango they are transmitters," dance teacher Laura Segade said.
"We try to make the man feel like a man and see himself as one. He comes to the class as a patient and leaves as a pupil, with a smile on his face."
Borda is Argentina's biggest public men's psychiatric hospital. The female dance partners are tango enthusiasts from outside.
Hospital psychiatrist Guillermo Honig says tango exercises patients' creativity and body awareness.
"I felt like I danced better today. I am more relaxed," says one patient, who identified himself as Maximiliano.
He is an outpatient and attends the classes with a dozen others who are hospitalised.
"I like the lyrics of tango -- the nostalgia, the melancholy."
The organiser of the tango workshop, psychologist Silvana Perl, patrols the corridors of the hospital rounding up participants.
Most patients resist.
"I haven't got time," says one, waiting in line for his medication.
"The workshop is an opportunity to break the hospital routine," Perl said.
"The idea is to break into the listless lives of the schizophrenic patients. Artistic commotion can awaken them and make them connect."
She returns to the canteen-dance floor with half a dozen participants who laugh and pair off with the volunteers as the music begins.
"It is like any regular tango class. Everyone does their best to complete the moves. They don't just do as they're told, they try to learn to do it for themselves," said dance instructor Roque Silles, 53.
"They give it their all to do something that a few minutes earlier seemed impossible."
To end the class, all the dancers join in singing tango songs.
"The world is a mess and always will be," they sing in the lines of one classic, "Cambalache."
One patient, Raul, did not join in the dancing but now asks to sing.
"I said I was a worthless tramp to her," he sings. "And I laughed about it."
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