A top Jakarta Metro Police psychiatrist says it is unlikely that a woman suffering amnesia after going missing the day before had been brainwashed.

"It takes a long time to brainwash a person, it can't be that fast," said Sr Nurcahyo, the head of the Jakarta Metro Police psychiatry division.

Laila Febriani, 26-year-old Transportation Ministry employee known as Lian, was reported missing by her family on April 7. A day later, she turned up dazed, confused and wearing a full veil at At-Ta'awun Mosque in Cisarua, Bogor, with no recollection of her past.

However, Nurcahyo said it was possible that Lian had been hypnotized.

"Hypnosis can be done in a short time, while brainwashing is planting a certain ideology in a person's mind by blocking their logic and common sense," he said.

Although he did not believe Lian had been brainwashed, Nurcahyo said it was possible to treat someone subjected to brainwashing methods through hypnotherapy.

"The therapy is like hypnosis, but it is performed under the consent of the client with the purpose of recovery and taking away the burden on the client's mind."

After hypnotherapy, a patient should be able to remember everything that happened during the period of brainwashing, he said.

"But we don't know for sure if Lian was brainwashed or hypnotized because we haven't met her," Nurcahyo said.

The Jakarta Police have requested the Association of Forensic Psychology for assistance to assess and treat Lian.