A partial or a total loss or a lack of memory: "The mother's amnesia was shown by her inability to recall past experiences or being unable to remember who she was."

"Amnesias can be caused by shocks, psychological disturbances, brain injuries, or certain kinds of illnesses."

Loss or lack of the ability to understand the form and nature of objects that are touched (stereognosis), a form of tactile agnosia: "Tactile amnesia is the loss of the ability to determine the shape of objects through the sense of touching."