What Kind Of Seizures Cause Memory Loss

If you are one of the almost 3.5 million Americans living with active epilepsy,¹ you might have experienced some difficulties with memory and mental processing. While not everyone who has epilepsy experiences amnesia or has difficulty remembering words, places, or faces, certain types of epilepsy and certain types of seizures do make this more likely.

How do seizures affect the brain?

When your brain is functioning as it should, rapid electrical impulses allow your brain cells to communicate effectively with one another. 

When you have a seizure, a sudden burst of uncontrolled electrical activity in your brain disrupts this communication and can even cause damage to the affected parts of your brain or specific communication networks.

Why does the location of the seizure matter?

Seizures can either be generalized (affecting both sides of the brain) or focal (located or beginning in one small part of the brain). Because seizures can affect different parts and functions of the brain, they don’t all appear the same or have the same long-term consequences.  

Take, for example, the hippocampus. This part of the brain is a bit like a highly efficient receptionist. It receives new information, and if it seems valuable, it sends it off to the relevant area of the brain for long-term storage. 

When you need that information again, the hippocampus goes to fetch it for you. Seizures that affect this part of the brain can make it more difficult for you to store and retrieve information, even if the areas of the brain that usually store the information are unaffected. 

Certain areas of the brain, namely Broca’s area, and Wernicke’s area, are responsible for speech and language. If seizures originate in or affect these areas of your brain, you may have difficulty accessing or understanding certain words.

What types of epilepsy cause memory loss?

Temporal lobe epilepsy

Because the temporal lobe plays a fundamental role in the formation, retention, and retrieval of memories, people with epilepsy often experience long-term memory deficits. Temporal lobe epilepsy has been found to impair episodic, semantic, and autobiographical memory. 

Research² suggests that the part of the temporal lobe affected by seizures plays a role in how memory systems are impacted. 

Seizures affecting the lateral temporal lobes have been linked to deficits in learning new material and some deterioration of working memory. Seizures that affect the mesial temporal lobes (specifically the hippocampi) have been found to interfere with the consolidation, retention, and recall of previously learned information. 

Transient epileptic amnesia

A distinctive epileptic syndrome typically occurs in late middle age, transient epileptic amnesia is often mistaken for dementia, cerebrovascular disease, or transient global amnesia. The condition is marked by amnestic seizures³ that typically last 15-30 minutes and occur approximately once per month. 

While some people only experience amnesia, other manifestations in addition to amnesia include olfactory hallucinations, brief loss of awareness, automatisms (for example, lip-smacking), and, very rarely, tonic-clonic seizures.

The condition has been linked to a group of persistent interictal (between seizures) memory complaints. These include accelerated long-term forgetting, autobiographical amnesia (inability to recall personal memories), and topographical amnesia (difficulty recognizing familiar locations). Antiepileptic treatment⁴ has been shown to control both seizures and interictal memory disturbances. 

Does age matter?

Research⁵ suggests that the age of onset of epilepsy plays a role in the mechanisms underlying epilepsy-related memory impairment. 

In the case of early-onset epilepsy, reduced autobiographical memory has been linked to frequent seizures and weakened working memory. Put simply, seizures at an early age are believed to alter how your brain works and develops. 

In the case of late-onset epilepsy, autobiographical memory impairments appear to be linked to depressive symptoms. This suggests that psychological maladjustment to the seizures — rather than the seizures themselves — may, in part, be responsible for memory difficulties. 

What can you do about it?

If you are experiencing problems with your memory, a neuropsychologist can conduct various cognitive tests to help you ascertain the nature and extent of the problem. Additional diagnostic procedures may also be used, such as blood work, EEGs, or brain imaging.

Your doctor may suggest direct and indirect approaches to improving your memory. Indirect approaches involve reducing the effect of whatever is causing the impairment. For example, measures to better control your seizures or address mental health concerns. Direct approaches focus on strategies to help you change how you store or retrieve information. 

The lowdown

While epilepsy is not necessarily associated with memory loss, certain types of epilepsy and seizures can result in memory loss and difficulty accessing or recalling information. 

However, in some cases, these impairments can be tackled through improved seizure control, specific techniques for improving memory, and changing how your brain stores information.