Recent memory. Ask the patient to recall three items or a brief story after a delay of 3 to 5 minutes. Be sure the information has been registered by asking the patient to repeat it immediately before initiating the delay. Provide distracters during the delay to prevent the patient from rehearsing the items repeatedly. A timer, such as a digital watch alarm should be used to provide a consistent interval from patient to patient, and to prevent the examiner from forgetting to ask for the test items!
Memory can be impaired on many different timescales. Impaired ability to register and recall something within a few seconds after it was said is an abnormality that blends into the category of impaired attention discussed earlier. If immediate recall is intact, then difficulty with recall after about 1 to 5 minutes usually signifies damage to the limbic memory structures located in the medial temporal lobes and medial diencephalon (see Neuroanatomy through Clinical Cases Chapter 18). Dysfunction of these structures characteristically causes anterograde amnesia, meaning difficulty remembering new facts and events occurring after lesion onset, and retrograde amnesia, meaning impaired memory of events for a period of time immediately before lesion onset, with relative sparing of earlier memories. Loss of memory without these time characteristics may signify damage to areas other than the medial temporal and medial diencephalic structures.