Forgotten Already? — A Study in Transient Global Amnesia

It is always difficult and scary to comprehend when a loved one starts to display symptoms of memory loss. Memory loss, often associated with amnesia, is typically divided into two categories: anterograde and retrograde amnesia. Anterograde amnesia is the inability to develop new memories after the event that caused the amnesia while retrograde amnesia is the inability to access memories prior to the event that caused the amnesia. Transient global amnesia (TGA), a clinical syndrome of anterograde amnesia, has been studied in efforts to greater understand the link between the brain and amnesia, and in hopes to lessen the worries of those affected by TGA.

Symptoms of transient global amnesia may stem from repetitive questioning but may devolve into a more serious long-term forgetfulness. TGA affects patients who are middle-aged and older, but the older one gets, the more susceptible they are to TGA. Such symptoms may be concerning to the families of TGA patients, especially if these symptoms are not documented or diagnosed.

In a recent clinical study led by Dr. Tarun P. Jain, potential in addressing the concerns of TGA is on the horizon. To attempt to pinpoint the root of the problem, magnetic resonance imaging (MRI) was used on 12 patients to analyze the hippocampus of each of their brains. These patients had TGA, displaying acute-onset confusion and amnesia. The study focused on diffusion weighted imaging in the MRI and any abnormalities that may have been discovered from the scans.

The results of the study found that each MRI scan of each patient displayed at least one abnormality in the hippocampus. Such abnormalities included punctate foci, which are bright spots on the MRI that signal cerebral white matter, which may be potentially harmful. This discovery allowed the research to, at minimum, correlate abnormalities within the brain to amnesia-related conditions such as TGA. Ultimately, the cause of TGA was not determined, but the study led to a greater understanding of TGA through the MRI scans of these various TGA patients.

Furthermore, the importance of understanding TGA and its symptoms lies in that TGA is often linked to other conditions such as strokes, epilepsy, and other head injuries. The research recommends that such conditions—ones that may produce transient amnesic syndromes—should be considered when patients visit their doctors. Routine MRI for strokes also may avoid the need for the protocols of TGA and repeat scans should symptoms return. TGA, although it is still classified as a clinical diagnosis, remains important to be diligent of should one display symptoms of this condition.

Although treatment is not necessarily required, as TGA symptoms generally go away within 24 hours, it is still frightening to witness one go through any level of memory loss. An apt and timely diagnosis would help to reassure not only patients, but their relatives, that TGA is a benign disorder. Even more so, if one displays uncertain symptoms, MRI findings of punctate foci in the hippocampus is nonetheless helpful to confirm or deny the diagnosis of TGA and most importantly, for peace of mind.