Disclosed is an apparatus including an unvoiced speech input device, a
decision unit and an alarm unit. The unvoiced speech input device
receives the unvoiced speech, and the decision unit determines whether or
not a signal received from the unvoiced speech input device is an
ordinary speech. The alarm unit receives a result of the decision from
the decision unit to give an alarm when the result of decision indicates
the ordinary speech. The alarm is given to a wearer of the apparatus if
he/she has made ordinary speech.