All are features of delirium except -
There is disturbance of immediate and recent memory which are responsible for registration, retention and recall of new memories. On recovery there is amnesia for the period of delirium, but remote memory is intact. That means there is no memory loss and patient remembers everything before the episode of delirium, there is amnesia only for the period of delirium.
Confusion
Disorientation
Hyperactivity
Loss of memory