A Case of “Spotty” Transient Global Amnesia

Abstract

A case of transient global amnesia occurring after sexual intercourse is presented with a somewhat unusual symptomatology. Instead of an all-encompassing amnesia, as has usually been reported in the literature, the patient’s amnesia was evident in spots. Therefore, transient global amnesia after sexual relations may go unnoticed in patients if the amnesia is temporary, as is usually the case, and is restricted to a few memories.

Introduction

Transient global amnesia (TGA) is a curious phenomenon whose etiology is still unknown. ¹ A case of TGA is presented with a somewhat unusual symptomatology. A 69-year-old male presenting with no medical or psychological issues and having a routine medical checkup 6 months prior engaged in weekly sexual relations on a Saturday morning with resulting orgasm. Shortly afterwards, the couple decided to go out for lunch and dress. As the husband waited for his wife, he glanced at some papers that he had written notes on the day before. He had trouble understanding two sentences that he had written, but had no problems with the others, and was puzzled over that, straining to think about what he had meant when he had written them while simultaneously thinking that it was odd. However, it was time for them to leave.

The couple talked as they drove down the road. At one point, the wife mentioned “COVID,” and he asked her what it was. It was a complete blank to him, as if heard for the first time. She was a bit puzzled, thinking he was trying to make a humorous point. He asked her again, and she repeated “COVID,” then gave some details. Nothing came to mind, and it became obvious that he was earnest. They became alarmed, and she gave more details. She began to ask various general questions: he was able to name the month and day, but not the year, but finally, using some events remembered as references, guessed correctly. He knew her name and the children’s names, his own name, but forgot the address where they lived. He then asked her to list some numbers, and he would try to repeat them, which he did with no problem.

Throughout the TGA episode, he showed normal facial and vocal communication, and his locomotor activity was unremarkable; there was no slurring of speech or transient ischemic attack and, whereas otherwise noted, his mental activity appeared normal.

They both agreed that he might be having a stroke and drove to a nearby hospital, where he was admitted. Preliminary tests for gross locomotor activity were normal. The previous questions for memory were given, with the same results; the patient described trying to remember those particular spots of memory as if straining with his hand to reach a glass that was barely out of reach. The patient was administered a CT scan and a MRI scan, both of which showed no physical abnormality, at which point he was admitted for observation. The diagnosis was TGA. The patient had never had any prior episode of amnesia, and he had not experienced a migraine the day in question. By that afternoon, he reported his memory back to normal and was released the next day. The patient has not had a recurrence after 2 years, or any physical or mental problems. ²

The details revolving around this instance of TGA are similar to others: it occurred in a mature citizen after sexual relations, the amnesia was retrograde, no physiological trauma was detected in the patient, there were no previously complicating health problems, and the symptomatology was transient (usually within 24 h) with spontaneous recovery (there are some cases of recurrence in the literature, one linked with a history of migraine).^3,4 Although anterograde amnesia is usually the case, retrograde amnesia in TGA has also been described in the literature. ⁵

The etiology of TGA has been speculated for some time but remains a mystery,^6,7 though one study found hippocampal lesions in as many as 50% of cases. ⁸ A differentiation must be made between TGAs occurring through sexual activity and otherwise, since in the latter, there are a number of potentially relevant variables, particularly migraine.^9–11

However, whereas in previous cases many of the patients’ symptoms were more severe, with the amnesia being truly global and sometimes exhibiting severe confusion,^12–14 the amnesia in the present instance was “spotty,” with only certain details in memory and comprehension of written material being evident. The diagnosis of TGA, therefore, may be erroneously rejected in patients if the amnesia is restricted to a few memories and is temporary.