A NURSING home care assistant put a plastic bin bag over the head of senile spinster in a ''sinister'' bid to keep her quiet, a court heard yesterday.

Lorna Malcolm placed the plastic swing-bin line over the head of Alzheimer's sufferer Miss Janet Young and ''gripped'' it at the bottom, in front of two shocked colleagues.

Malcolm, 21, of Johnston Avenue, Cornton, Stirling, denied causing alarm, and claimed she had just made the bag into a hat to amuse the old lady, but Sheriff William Reid, who found her guilty of breach of the peace, said he did not believe her.

He said: ''If she had gone into the witness box and represented this as a crass and misunderstood joke by someone who was still 20 at the time, that might have been different, but she did not.

''The sinister aspect was that this was almost like a prelude of asphyxiation. She placed a bag over an old lady's head and tucked in the bottom.''

The sheriff called for social inquiry and community service reports on Malcolm, and deferred sentence until January.

He said he wanted to know if Malcolm, who was sacked after the incident and now works for the Holiday Inn, was a suitable person to work with old people in future.

Stirling Sheriff Court heard that the incident occurred after Miss Young, 90, had become noisy and upset and thought her brother was due to visit her.

Malcolm, 21, pled not guilty to causing a breach of peace at the Fairview Nursing Home in Cowie Road, Bannockburn, on June 22 this year by putting the bag on Miss Young's head to the ''alarm and disturbance'' of two other employees, Mrs Margery Condie and Mrs Denise Muir.