Final answer:
Magnetic resonance imaging (MRI) is not advisable for individuals with metal plates in their head, as it can dislodge the implants. CT scans or ultrasound may be more suitable options.
Step-by-step explanation:
An imaging technique that would not be advisable for a person with a metal plate in their head is magnetic resonance imaging (MRI). MRI uses strong magnetic fields to create detailed images of the brain, but it can dislodge iron-containing metallic implants, such as metal plates.
For individuals with metal plates in their head, other imaging techniques like CT scans or ultrasound may be more suitable options as they do not involve strong magnetic fields.