Neural Correlates of Recognition Memory in Children with Febrile Seizures: Evidence from Functional Magnetic Resonance Imaging

Abstract

Febrile seizures (FS) are assumed to not have adverse long-term effects on cognitive development. Nevertheless, FS are often associated with hippocampal sclerosis which can imply episodic memory deficits. This interrelation has hardly been studied so far. In the current study 13 children who had suffered from FS during infancy and 14 control children (7 to 9-years-old) were examined for episodic and semantic memory with standardized neuropsychological tests. Furthermore, using functional magnetic resonance imaging (fMRI) we studied neuronal activation while the children performed a continuous recognition memory task. The analysis of the behavioral data of the neuropsychological tests and the recognition memory experiment did not reveal any between-group differences in memory performance. Consistent with other studies fMRI revealed repetition enhancement effects for both groups in a variety of brain regions (e.g., right middle frontal gyrus, left parahippocampal gyrus) and a repetition suppression effect in the right superior temporal gyrus. Different neural activation patterns between both groups were obtained selectively within the right supramarginal gyrus (BA 40). In the control group correct rejections of new items were associated with stronger activation than correctly identified old items (HITs) whereas in the FS group no difference occurred. On the background that the right supramarginal gyrus is assumed to mediate a top-down process to internally direct attention toward recollected information, the results could indicate that control children used strategic recollection in order to reject new items (recall-to-reject). In contrast, the missing effect in the FS group could reflect a lack of strategy use, possibly due to impaired recollective processing. This study demonstrates that FS, even with mainly benign courses, can be accompanied by selective modifications in the neural structures underlying recognition memory.

Intelligence and memory outcomes within 10 years of childhood convulsive status epilepticus

“…A potential explanation for this discrepancy could be that the incidental recognition memory paradigm adopted for our early outcomes study recruits different brain structures and mental processes than the CMS. This has been indicated in several past studies that have demonstrated dissociations in performance on incidental recognition and explicit recognition tasks [35], [36], [37]. In support of this, our original one-year outcome data showed no significant correlations between CMS and incidental recognition memory scores in the 8 individuals where both measures were collected [38].…”

Electroencephalography source localization analysis in epileptic children during a visual working‐memory task

“…More specifically, our analysis revealed consistent differences between the two groups in the parietal lobes. Importantly, our findings are in line with other studies investigating abnormalities of the brain function due to epilepsy with the use of anatomical MRI, fMRI and EEG recordings 71‐80 . More specifically, regarding children with epilepsy, Besenyei et al 80 used anatomical MRI and resting state EEG recordings to identify the abnormal brain activity in children with benign rolandic epilepsy.…”

“…Importantly, our findings are in line with other studies investigating abnormalities of the brain function due to epilepsy with the use of anatomical MRI, fMRI and EEG recordings. [71][72][73][74][75][76][77][78][79][80] More specifically, regarding children with epilepsy, Besenyei et al 80 used anatomical MRI and resting state EEG recordings to identify the abnormal brain activity in children with benign rolandic epilepsy. Using LORETA, they found an increase activity, compared to controls, in the temporal and inferior parietal lobule.…”

Generalized epilepsy and febrile seizures plus (GEFS+) in a series of 22 patients

“…Nevertheless, there is evidence suggesting an intellectual/behavioral deficit when FS appear during the first year of life, which can be related to a specific neuronal vulnerability in the early stages of cerebral development [13]. Besides, current evidence has supported the linkage between a history of FS and later memory/attention deficits in childhood [12,31] with a possible correlation with prolonged FS (longer than 10 min) [12]. Some other publications have suggested that FS (including those with a "benign" course) could impair the cognitive performance in children who exhibit slow responses when evaluating recognition memory tasks [31].…”