My Experience with Transient Global Amnesia (TGA)
Mysterious, sudden memory loss can be frightening - here is what happened to me
Posted Feb 24, 2019
Early one winter Sunday morning, I got out of bed at 5:30 to walk my dog; the next 8 to 10 hours of my life are a complete blank.
My wife awoke to find me lying on a bed in another room about an hour and a half later, and I apologized for not having walked the dog. However, there had been a snowfall the night before and the dog was wet, my boots were wet, and our tracks could clearly be seen outside in the fresh snow – obviously, the dog had been walked. As we spoke, my wife became more alarmed because I was disoriented and in a state of confusion, and I kept asking the same questions over-and-over again. I apparently realized my wife’s distress, as I prefaced my questions with calm reassurances that I understood that what I was about to ask might seem troubling to her. What escaped me at the time was that the most troubling part of the questions was that I had already asked them several times only moments before.
And each time I asked a question, I used exactly the same words, voice inflection, and hand gestures.
I had not lost personal memories. I knew who I was, I knew who my wife was, and I knew who my dog was. The problem was that I could not put anything new into my memory or keep track of anything that had transpired more than a minute or two ago. It was as if my memory erased everything and reset every 90 seconds.
I could also not remember basic facts, like what day of the week it was or who the President of the United States was. (One of the few bright spots in this story!)
Fortunately, my wife hustled me into a car and drove me to the emergency room of the hospital. I spent the next several hours meeting with doctors and other health care workers, getting an MRI, CAT scans, and various other tests. I remember none of these things, and I am relying on my wife’s description of events to relate this to you now. I stayed in the hospital for almost two days.
Sometime around mid-afternoon on that same Sunday, my mental fog began to lift. While I have no memory whatsoever of anything that happened before noon, I have a few scattered, disorganized memories from the afternoon – almost like still photographs preserved in a photo album without any meaningful connection between them.
It was a good 24 hours before I was back to normal.
When a man my age comes to the hospital with sudden memory problems, the first impulse is always to search for signs of a stroke, a tumor, or some other malignant cardiac or neural event. I am happy to report that all of the brain scans came back with good news – there were no blockages, tumors, or other abnormalities present.
So, what the Hell happened to me?
There are Different Types of Amnesia
For many years, I have taught courses in which the topic of “amnesia” comes up in at least a superficial way, and there are many different kinds of amnesia.
The type that perhaps comes to mind most quickly is the amnesia that accompanies a Dissociative Fugue State. In a fugue state, people not only suffer from retrograde amnesia (an inability to recall the past), but they also have erased all biographical information from their memory. They do not know who they are and they do not recognize anyone that they know, no matter how intimate the relationship with that person might be. In spite of its dramatic portrayals on TV soap operas, most fugue states last just a matter of hours, or at most, days. Fugue states usually occur in response to sudden stressful or traumatic life events.
Amnesia resulting from physical problems with the brain are more common. Retrograde amnesia occurs when one cannot recall events from one’s own past. Sometimes, retrograde amnesia occurs following a blow to the head that results in the loss of events that occurred just prior to the injury, but the memory loss can be much more extensive and debilitating if there has been severe brain damage.
Anterograde amnesia is the inability to form new memories, and it may result from damage to the hippocampus that has occurred through accident or disease. It may also occur in response to long-term alcohol abuse or medical conditions that have effects on the relevant parts of the brain.
There are many well-known cases of individuals who have experienced these types of amnesia, with one of the most famous being that of Clive Wearing, a gifted British musician who suffered both profound anterograde and retrograde amnesia, resulting in a desperate existence. He lived the last part of his life in brief 30-second episodes, with no sense of a past or future.
Being a psychologist, I have often wondered what the subjective experience of an individual in an amnesic state might be like. I am disappointed to report that my own experience with this did nothing to enlighten me, as I cannot remember much of what went on during that time, including my own emotional reactions and mental reflections.
It turns out that what I had experienced was a textbook case of Transient Global Amnesia, or “TGA” for short.
Transient Global Amnesia (TGA)
TGA is a relatively rare syndrome. It almost never happens to anyone under the age of 50, and its frequency among people over 50 is estimated to about 25 out of 100,000 on a yearly basis. The sweet spot seems to be between the ages of 60-65; my own episode occurred exactly three weeks after my 66th birthday.
With TGA, one does not lose personal memories. You remember who you are and recognize significant other people in your life, but you cannot retain anything and you badger those around you with an endlessly recycling loop of questions. Questions about where you are and how you got there are understandably among the favorites. Most cases persist for about 6 to 12 hours, and it almost always resolves itself within 24 hours.
As terrifying as this was for me, it is a relief to know that it is relatively harmless. It is not a harbinger of stroke or dementia, and it is very unlikely to recur (although about 15% of individuals may experience a second episode).
One of the maddening things about it is that it is completely unpredictable and it has no known cause. I am not in bad shape for a sixty-six-year-old guy, and I am happy to say that to my knowledge I do not have any serious, life-threatening health conditions. Having said this, there does not appear to be a set of physical factors that could have helped me see this coming anyway.
A range of conditions have been hypothesized to predict TGA, but the only one with any degree of support in the medical community is that individuals with a history of migraines (which by the way, I do not have) may be most likely to experience it.
Some commonly reported triggers of a TGA episode include head trauma, severe physical exertion, acute emotional distress, sudden immersion in hot or cold water, or even sexual intercourse. None of these triggers were present in my case, however, nor did I see any of them in the numerous case studies of TGA that I investigated after my experience.
In short, if you experience this frightening syndrome, you will probably be left with little understanding of exactly why it happened and little memory of what it was like. I am publishing this essay for the benefit of others who, like me, may not even know that such a syndrome exists. Awareness of TGA will not prevent it from coming your way, but it might give you insight into what is going on with a friend or loved one who suddenly seems confused and forgetful.