To him, he felt that he had just come to consciousness for the first time every time he was unable to hold on to information. This case also can be used as evidence that there are different memory systems for declarative and non-declarative memory. This case was more evidence that the hippocampus is an important part of the brain in remembering past events and that declarative and non-declarative memories have different processes in different parts of the brain. Patient R.B. Patient R.B. was a normally functioning man until the age of 52. At age 50, he had been diagnosed with angina and had surgery for heart problems on two occasions. After an ischemic episode (reduction of blood to the brain) that was caused from a heart bypass surgery, R.B. demonstrated a loss of anterograde memory, but almost no loss of retrograde memory, with the exception of a couple of years before his surgery, and presented no sign of any other cognitive impairment. It wasnt until after his death that researchers had the chance to examine his brain, when they found his lesions were restricted to the CA1 portion of the hippocampus. This case study led to important research involving the role of the hippocampus and the function of memory. Patient G.D. Patient G.D. was a white male born in 1940 who served in the Navy. He was diagnosed with chronic kidney failure and received hemodialysis treatment for the rest of his life. In 1983, he went to the hospital for elective parathyroidectomy.
Other neurological problems are likely to be present in combination with this type of Amnesia, such as problems with the medial temporal lobe and frontal lobe dysfunction. Korsakoffs syndrome is also known to be connected with confabulation. The persons short-term memory may appear to be normal, but the person may have a difficult time attempting to recall a past story, or with unrelated words, as well as complicated patterns. Korsakoffs syndrome is unique because it involves both anterograde and retrograde amnesia. Drug-induced amnesia is intentionally caused by injection of an amnestic drug to help a patient forget surgery or medical procedures, particularly those not performed under full anesthesia, or likely to be particularly traumatic. Such drugs are also referred to as "premedicants". Most commonly, a 2-halogenated benzodiazepine such as midazolam or flunitrazepam is the drug of choice, although other strongly amnestic drugs such as propofol or scopolamine may also be used for this application. Memories of the short time-frame in which the procedure was performed are permanently lost or at least substantially reduced, but once the drug wears off, memory is no longer affected. Situation-specific amnesia can arise in a variety of circumstances (for example, committing an offence, child sexual abuse) resulting in PTSD. It has been claimed that it involves a narrowing of consciousness with attention focused on central perceptual details and/or that the emotional or traumatic events are processed differently from ordinary memories. Transient epileptic amnesia is a rare and unrecognized form of temporal lobe epilepsy, which is typically an episodic isolated memory loss.