The Impaired Function Of Cognitive Control In Elderly With Mild Cognitive Impairment In Shenzhen Communities

[Background] Mild cognitive control(MCI)is an intermediate stage between normal aging and Alzheimer disease.A large number of studies have shown that the function of cognitive control in individuals with MCI has impaired,but few studies have explored the impaired function from the perspective of the capacity of cognitive control.With the introduction of the information theory account of cognitive control,the concept of the capacity of cognitive control(CCC)and its algorithm have been clearly defined in recent years.However,the relationship between CCC and behavior indicators in multiple cognitive control tasks has not been clarified.This study was designed to investigate the behavioral association indicators of CCC,and investigate whether the impaired function of cognitive control in MCI elderly showed a decrease in CCC.This study predicts that(1)CCC as a bottleneck of information processing should only be related to behavioral performance under the high load conditions;(2)the CCC of MCI people is lower compare with the healthy elderly.[method] We used the backward masking Majority Function Task(MFT-M)to identify the CCC of 63 college students,and we adopted the MFT-oddball task which is a combination of Majority Function Task(MFT)and oddball task to examine the cognitive control performance of the 63 subjects under different cognitive load conditions.Correlation analysis and regression analysis were used to investigate the association between behavioral indicators(accuracy rate,reaction time)under each condition of MFT-oddball tasks and their CCC.In Study 2,we conducted a cognitive function test on 245 elderly people over 50 years old in Shenzhen communities and we distinguished 54 MCI people from them.30 MCI people and age/education matched healthy control participated in the MFT-M task which was used to identify the CCC and the MFT-oddball task.[Results] The results of Study 1 showed that CCC was significantly correlated with the performance of the subjects under high load conditions,but not correlated with the performance under low load conditions.The results of Study 2 showed that the CCC of MCI people was significantly lower compare with the healthy elderly.In the MFT-oddball task,the CCC of MCI people was positively correlated with their performance under high load conditions,while there is no relationship between the CCC of healthy control and their performance under any conditions,suggesting that the capacity of information processing of MCI people reached the bottleneck under high load conditions.The HC elderly can complete the processing tasks under all cognitive load conditions,suggesting that the cognitive function of MCI people has reduced.[Conclusion] CCC,as the bottleneck of information processing,was related to behavioral performance under high load conditions rather than low load conditions.The decline of CCC can be an indicator of impaired cognitive function in people with MCI,and impaired function of cognitive control may be a key impairment of MCI.