The troubled star will stay until 17 February unless she legally demands to be released or her doctor confirms she is her well enough for outpatient treatment.
'It is a terrible situation,' a source close to the Spears family tells People.com. 'Britney is in a padded room. Her family is so worried about her.'
A mental health expert explains that 'a quiet room, some of which are padded' is used 'if a patient becomes combative'.
Generally, in extreme, life-threatening situations - when a patient is a threat to themselves or medical staff leather restraints can be used or a psychiatrist can inject a person with psychiatric medication.
There is nothing to suggest Britney, 26, is in that situation.
At the moment she is allowed to wear her own clothes, make and receive phone calls - but not on her mobile - and see visitors every day.
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