Individuals with-Mild Cognitive Impairment (MCI) often complain of difficulty remembering to carry out intended actions. We investigated the relative efficacy of a different reminder in performing a time-based Prospec...Individuals with-Mild Cognitive Impairment (MCI) often complain of difficulty remembering to carry out intended actions. We investigated the relative efficacy of a different reminder in performing a time-based Prospective Memory (PM) task. The PM performance of 24 participants with amnesic Mild Cognitive Impairment (AMCI) has been compared with that of 24 healthy controls. As ongoing task, samples of the Attentive Matrices Test were used. In the PM task subjects were requested to write an “X” every three minutes during a 9 minutes period. Participants received the task consisting either in a low demand condition (checking number “5”) or in a high demand condition (checking numbers “1”, “4”, “9”). In order to be as punctual as possible, participants were asked to simultaneously write the “X” at task time expiration, using a digital clock. Time monitoring was recorded. Reminder occurring was manipulated in that participants could receive critical, accidental or completely absent reminder. As expected, high cognitive demand was negatively correlated with PM performance and time monitoring. Unexpectedly, all the participants did not benefit from the critical reminder. These findings demonstrated, from a behavioral perspective, that Working Memory (WM) and PM processes are not based on the same memory system and PM may require WM resources at high demand.展开更多
Background With an aggravated social ageing level, the number of patients with Alzheimer's disease (AD) is gradually increasing, and mild cognitive impairment (MCI) is considered to be an early form of Alzheimer&#...Background With an aggravated social ageing level, the number of patients with Alzheimer's disease (AD) is gradually increasing, and mild cognitive impairment (MCI) is considered to be an early form of Alzheimer's disease. How to distinguish diseases in the early stage for the purposes of early diagnosis and treatment is an important topic. Aims The purpose of our study was to investigate the differences in brain cortical thickness and surface area among elderly patients with AD, elderly patients with amnestic MCI (aMCI) and normal controls (NC). Methods 20 AD patients, 21 aMCIs and 25 NC were recruited in the study. FreeSurfer software was used to calculate cortical thickness and surface area among groups. Results The patients with AD had less cortical thickness both in the left and right hemisphere in 17 of the 36 brain regions examined than the patients with aMCI or NC. The patients with AD also had smaller cerebral surface area both in the left and right hemisphere in 3 of the 36 brain regions examined than the patients with aMCI or NC. Compared with the NC, the patients with aMCI only had slight atrophy in the inferior parietal lobe of the left hemisphere, and no significant difference was found. Conclusion AD, as well as aMCI (to a lesser extent), is associated with reduced cortical thickness and surface area in a few brain regions associated with cognitive impairment. These results suggest that cortical thickness and surface area could be used for early detection of AD.展开更多
Previous studies have shown that amnestic mild cognitive impairment(aMCI)involves in the morphological abnormalities of multiple regions,including cortical thickness,sulcus depth,surface area,gray matter volume,jacobi...Previous studies have shown that amnestic mild cognitive impairment(aMCI)involves in the morphological abnormalities of multiple regions,including cortical thickness,sulcus depth,surface area,gray matter volume,jacobian metric and average curvature.All the measures have unique neuropathological and genetic meanings.However,most existing methods simply average or concatenate these measures when constructing the classifiers,which may include redundant information and ignore the relationships among them.In this study,we treat each measure as a task in our multitask learning framework.Considering the actual situation that we do not know the correlation between tasks in advance,we use a robust multitask feature learning(rMTFL)method to select a group of features among correlated measures and provide additional information by identifying outlier tasks at the same time.Then,we train several SVM classifiers and for each measure,we input the selected features into the corresponding SVM classifier.Finally,we use an ensemble classification strategy to combine the results of these classifiers based on the accuracy to make the final prediction.We use the leave-one-out cross-validation to evaluate our proposed method with 46 amnestic mild cognitive impairment(aMCI)and 52 normal controls(NC).The results show that rMTFL algorithm is superior to the group lasso method and average curvature is the outlier task based on multidimensional surface measures.展开更多
文摘Individuals with-Mild Cognitive Impairment (MCI) often complain of difficulty remembering to carry out intended actions. We investigated the relative efficacy of a different reminder in performing a time-based Prospective Memory (PM) task. The PM performance of 24 participants with amnesic Mild Cognitive Impairment (AMCI) has been compared with that of 24 healthy controls. As ongoing task, samples of the Attentive Matrices Test were used. In the PM task subjects were requested to write an “X” every three minutes during a 9 minutes period. Participants received the task consisting either in a low demand condition (checking number “5”) or in a high demand condition (checking numbers “1”, “4”, “9”). In order to be as punctual as possible, participants were asked to simultaneously write the “X” at task time expiration, using a digital clock. Time monitoring was recorded. Reminder occurring was manipulated in that participants could receive critical, accidental or completely absent reminder. As expected, high cognitive demand was negatively correlated with PM performance and time monitoring. Unexpectedly, all the participants did not benefit from the critical reminder. These findings demonstrated, from a behavioral perspective, that Working Memory (WM) and PM processes are not based on the same memory system and PM may require WM resources at high demand.
基金Collaborative Innovation Center for Translational Medicine at Shanghai Jiao Tong University School of Medicine TM201728National Nature Science Foundation of China 81571298+2 种基金Shanghai health system excellent talent training program (excellent subject leader) project 2017BR054Shanghai Municipal Education Commission-Gaofeng Clinical Medicine Grant Support 20172029Shanghai Pujiang Program 17PJD038.
文摘Background With an aggravated social ageing level, the number of patients with Alzheimer's disease (AD) is gradually increasing, and mild cognitive impairment (MCI) is considered to be an early form of Alzheimer's disease. How to distinguish diseases in the early stage for the purposes of early diagnosis and treatment is an important topic. Aims The purpose of our study was to investigate the differences in brain cortical thickness and surface area among elderly patients with AD, elderly patients with amnestic MCI (aMCI) and normal controls (NC). Methods 20 AD patients, 21 aMCIs and 25 NC were recruited in the study. FreeSurfer software was used to calculate cortical thickness and surface area among groups. Results The patients with AD had less cortical thickness both in the left and right hemisphere in 17 of the 36 brain regions examined than the patients with aMCI or NC. The patients with AD also had smaller cerebral surface area both in the left and right hemisphere in 3 of the 36 brain regions examined than the patients with aMCI or NC. Compared with the NC, the patients with aMCI only had slight atrophy in the inferior parietal lobe of the left hemisphere, and no significant difference was found. Conclusion AD, as well as aMCI (to a lesser extent), is associated with reduced cortical thickness and surface area in a few brain regions associated with cognitive impairment. These results suggest that cortical thickness and surface area could be used for early detection of AD.
基金supported by the National Key Research and Development Program of China(2016YFC1306300)the National Natural Science Foundation of China(Grant No.61633018,81622025 and 81471731)Beijing Municipal Commission of Health and Family Planning(PXM2019_026283_000002)。
文摘Previous studies have shown that amnestic mild cognitive impairment(aMCI)involves in the morphological abnormalities of multiple regions,including cortical thickness,sulcus depth,surface area,gray matter volume,jacobian metric and average curvature.All the measures have unique neuropathological and genetic meanings.However,most existing methods simply average or concatenate these measures when constructing the classifiers,which may include redundant information and ignore the relationships among them.In this study,we treat each measure as a task in our multitask learning framework.Considering the actual situation that we do not know the correlation between tasks in advance,we use a robust multitask feature learning(rMTFL)method to select a group of features among correlated measures and provide additional information by identifying outlier tasks at the same time.Then,we train several SVM classifiers and for each measure,we input the selected features into the corresponding SVM classifier.Finally,we use an ensemble classification strategy to combine the results of these classifiers based on the accuracy to make the final prediction.We use the leave-one-out cross-validation to evaluate our proposed method with 46 amnestic mild cognitive impairment(aMCI)and 52 normal controls(NC).The results show that rMTFL algorithm is superior to the group lasso method and average curvature is the outlier task based on multidimensional surface measures.
