A person was mentally incapable of appreciating the nature and effect of his or her act during the execution of the will.

A person was mentally capable of appreciating the nature and effect of his or her act at the time of the execution of the will, but became mentally incapable shortly before his or her death.

A person was mentally incapable of appreciating the nature and effect of his or her actions but experienced a lucidum intervallum (lucid interval) during the execution of the will.

A person was unduly influenced by a beneficiary, but not to the extent that he no longer formed his own volition.