Amnesiac patients are often unable to retain information long-term, but can perform short term memory tasks well, which supports the idea that short-term and long-term memory use different structures within the brain. However, recent research has also shown that amnesic patients struggle with short-term memory related to complex or related stimuli, which has led researchers to believe that parts of the brain damaged in amnesia may be related to both short-term and long-term memory. Other patients seem to have problems with short-term memory, while their long-term memory remains intact.