Unfortunately, due to a lack of overall known neurological knowledge, Molaisons surgeons removed his bilateral medial temporal lobe, causing profound AA and RA. The removed brain structures included the hippocampus, the amygdala, and the parahippocampal gyrus, now called the medial temporal lobe memory system. HM was one of the most studied memory cases to date and started the examination of neurological structures in relation to memory. Patients who have RA due to surgery are "P.B." and "F.C." who had unilateral removal of the medial areas in the left temporal lobe. Controlled induction
Clinically induced RA has been achieved using different forms of electrical induction. Electroconvulsive therapy (ECT), used as a depression therapy, can cause impairments in memory. Tests show that information from days and weeks before the ECT can be permanently lost. The results of this study also show that severity of RA is more extreme in cases of bilateral ECT rather than unilateral ECT. Impairments can also be more intense if ECT is administered repetitively (sine wave simulation) as opposed to a single pulse (brief-pulse stimulation). Electroconvulsive shock (ECS): The research in this field has been advanced by using animals as subjects. Researchers induce RA in rats, for example, by giving daily ECS treatments. This is done to further understand RA. Brain structures
The most commonly affected areas are associated with episodic and declarative memory such as the hippocampus, the diencephalon, and the temporal lobes.
The reminder effect consists of re-exposing the patient to past personal information, which cannot reverse RA. Thus, reminding the patient about details of their life has no scientific bearings on recovering memory. Fortunately, memory can be and usually is recovered due to spontaneous recovery and plasticity. Case studies
Since researchers are interested in examining the effects of disrupted brain areas and conducting experiments for further understanding of an unaffected, normal brain, many individuals with brain damage have volunteered to undergo countless tests to advance our scientific knowledge of the human brain. For example, Henry Molaison (HM) was someone with significant brain damage and participated in a lot of neurological research. Furthermore, he was also the most tested person in neuropsychology. All living people who participate are referred to in literature using only their initials to protect privacy. Each case of RA has led to different symptoms and durations, where some patients have exhibited an inability to describe future plans, whether in the near future (e.g., this afternoon) or in the distant future (e.g., next summer) because of their inability to consolidate memories. Furthermore, researchers have also found that some patients can identify themselves and loved ones in photographs, but cannot determine the time or place the photo was taken. It has also been found that patients with RA greatly differ from the general population in remembering past events.A few case examples are:

After a head injury, AB had to relearn personal information. Many of ABs habits had also changed.