Metamemory monitoring ability in patients with idiopathic generalized epilepsy

Abstract

Objective To investigate the memory monitoring ability in patients with idiopathic generalized epilepsy(IGE) and explore the mechanism of the memory impairment. Methods The feeling of knowing(FOK) paradigm of episodic memory(EM) and semantic memory(SM)were established and subsequently administered in 31 patients with IGE(IGE group) and 30 healthy controls(HC group) participants who were matched in age, sex and educational level. Results Compared with HC group ( feeling of knowing of episodic memory (FOK-EM) FOK accuracy (85.29±16.84)%; feeling of knowing of sematic memory (FOK-SM) recall (76.61±18.66)%), the FOK-EM FOK accuracy ((64.03±22.10)%) and FOK-SM recall ((53.27±26.91)%) in IGE group were significantly decreased(t=-4.215, P<0.01; t=-3.677, P<0.01 ). The correct judgment and correct recognition of FOK-EM ((51.16±32.93)%) and the false judgment and correct recognition ((21.07±24.38)%) of FOK-EM in the IGE group were significantly different with the HC group (the correct judgment and correct recognition of FOK-EM: (79.34±27.26)% and the false judgment and correct recognition of FOK-EM: (2.45±5.38)%; t=-3.634, P<0.01; t=4.149, P<0.01). Most importantly, the false judgment and correct recognition of FOK-EM were correlated with the Digital Span Test, Vocabulary Fluency Test and the Stroop effect in IGE group (r=-0.309, P<0.05; r=-0.355, P<0.01; r=-0.354, P<0.05; r=0.602, P<0.01). Conclusion The results show that the IGE group made less accurate metamemory monitoring than the HC group by underestimating their memory performance on FOK-EM, whereas the semantic metamemory monitoring is not impaired in IGE group. More importantly, the impairment of memory monitoring was correlated with the deficit of executive function, indicating that this mechanism can be an influential factor of memory disorder in IGE. It also indicates that the episodic and semantic metamemory monitoring depend on different neural networks. Key words: Epilepsy; Memory; Metamemory monitoring; Feeling of knowing