Accelerated long-term forgetting and autobiographical amnesia, which are invisible to standard memory tests, help to explain the discrepancy between normal test performance and prominent memory complaints among patients with epilepsy. Transient epileptic amnesia is an under-recognized but treatable cause of transient memory impairment. This test is usually ordered if youve had more than one episode of transient global amnesia or if your doctor suspects that youre having seizures. People with epilepsy often have changes in their brain waves, even when theyre not having a seizure. Further work is required to establish whether the interictal memory impairment is due to physiological or structural disturbance. An EEG records the brains electrical activity via electrodes attached to the scalp. In this syndrome, the principle manifestation of seizures is episodes of transient amnesia during which other cognitive functions remain intact. The seizures respond promptly to treatment, whereas the interictal impairments generally persist. Transient epileptic amnesia (TEA) is a form of TLE with a particularly intimate relation to memory (Kapur and Markowitsch, 1990 Zeman et al., 1998 Butler et al., 2007). The seizure focus lies in the medial temporal lobes. It is associated with novel forms of interictal memory disturbance: accelerated long-term forgetting, remote memory impairment, especially affecting autobiographical memory, and topographical memory impairment. Transient epileptic amnesia is a distinctive syndrome of temporal lobe epilepsy principally affecting middle-aged people, giving rise to recurrent, brief attacks of amnesia, often occurring on waking.

Recent research has established that this is indeed the case, and indicates that characteristic varieties of interictal memory disturbance co-occur with this form of epilepsy. doi:10.Case reports over the past 100 years have raised the possibility that epilepsy can manifest itself in episodes of amnesia.

Acute-Onset Amnesia: Transient Global Amnesia and Other Causes. What Does Transient Global Amnesia Really Mean? Review of the Literature and Thorough Study of 142 Cases. Quinette P, Guillery-Girard B, Dayan J et al. Transient Global Amnesia: Diffusion-Weighted Imaging Lesions and Cerebrovascular Disease. Optimal Diffusion-Weighted Imaging Protocol for Lesion Detection in Transient Global Amnesia. High-Resolution Diffusion-Weighted Imaging Increases Lesion Detectability in Patients with Transient Global Amnesia. Post-traumatic amnesia, has a history of trauma 6 Psychogenic amnesia, more-so affects semantic memory compared to episodic memory, while TGA is the opposite 6ĭrug-related amnesia, typically has features of encephalopathy 6 Transient epileptic amnesia, typically presents upon waking while TGA does not 6 hippocampal ischemic), typically exists with other neurological deficits 6 The condition rarely recurs in ~5% of patients 5,6. These changes generally appear after symptom resolution, and the highest rate of detection is approximately 2 days after symptom onset 6. These lesions can be bilateral and even multifocal 2-4. Prospective and retrospective studies based on a small number of transient global amnesia patients can detect small punctate regions of abnormally restricted diffusion on DWI/ADC sequences in the CA1 area of the hippocampus (lateral edge of the hippocampal gyrus abutting the temporal horn). Radiographic featuresĬT brain and conventional sequences of MRI brain may show no abnormalities, especially while the patient is symptomatic. epileptic phenomena, stroke, focal ischemia) have been proposed with no consensus on the exact mechanism 1,6. Most cases show complete resolution of symptoms within a few hours from onset of symptoms 6. Episodic memories are more-so affected than semantic memories 6. AssociationsĪnterograde and partial retrograde amnesia lasting less than 24 hours without any other neurological or congestive symptoms 6. Transient global amnesia is most common in the 50-70 year age range ref.