Our research has demonstrated that patients with TEA often have difficulty in recalling both verbal and visual information over days to weeks, even if this information was well learned initially.
Accelerated long-term forgetting (ALF) may be described as the abnormally rapid loss of recently learned material from memory.
We have also found that ALF is often accompanied by a loss of remote memory – the ability to remember things that happened years ago.
Even though accelerated memory loss is a relatively common problem amongst TEA patients, it is undetected by standard tests of memory. Typically these tests examine the ability to store information for up to 30 minutes but the problem of accelerated long-term forgetting in TEA patients is not generally noticeable at this point. It becomes apparent over the following days and weeks.
There are 4 possible reasons why TEA patients experience accelerated forgetting:
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Seizure activity
Seizures in TEA patients commonly occur upon waking suggesting a link between TEA and sleep. It is possible that abnormal electrical activity during sleep disrupts the process of memory consolidation which normally occurs when we sleep.
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Brain Pathology
Damage to particular structures in the temporal lobe may both cause attacks of TEA and interfere with the handling of memories.
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Anticonvulsant Medication
Antiepileptic drugs sometimes affect memory. However, this is unlikely to be the cause of TEA, as patients tend to report memory problems before they start taking the antiepileptic drugs and can experience improvement in their memory after taking them.
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Psychological Mechanisms
Research has reported that low mood and poor self-esteem are associated with memory problems. These are important factors when investigating patients with epilepsy in general. However, in TEA they do not appear to play an important role in accelerated forgetting.