Multiple Cognitive Deficits in Amnestic Mild Cognitive Impairment

Abstract

Objective: To determine if more widespread cognitive deficits are present in a narrowly defined group of patients with the amnestic form of mild cognitive impairment (MCI). Methods: From a larger sample of patients clinically diagnosed as meeting the criteria of Petersen et al. for amnestic MCI, we selected 22 subjects who had Clinical Dementia Rating scores of zero on all domains besides memory and orientation. These MCI subjects with presumably isolated memory impairments were compared to 35 age-matched normal controls and 33 very mild Alzheimer’s disease (AD) patients on a battery of neuropsychological tests. Result: In addition to the expected deficits in episodic memory, the amnestic MCI group performed less well than the controls but better than the AD group on design fluency, category fluency, a set shifting task and the Stroop interference condition. Over half the amnestic MCI group (vs. none of the normal controls) scored at least 1 standard deviation below control means on 4 or more of the nonmemory cognitive tasks. Conclusions: Isolated memory impairment may be fairly uncommon in clinically diagnosed amnestic MCI patients, even when the criteria for amnestic MCI are fairly narrow. Additional cognitive impairments are likely to include fluency and executive functioning. These more diffuse deficits argue for comprehensive cognitive assessments, even when the patient and family are reporting only memory decline, and are consistent with the increase in attention paid to the heterogeneity of MCI.

Analysis of EEG Complexity in Patients with Mild Cognitive Impairment

“…In addition, associated complex reduction of the parietal lobe suggested that cognitive impairment may not only have simple memory loss but other brain functions such as motion and sensation function decline. This result is consistent with Krame et al [24] research result. According to above, we deduced: in the same time series, EEG signals shows higher rate of new model in normal elderly people than in cognitive impairment patient, and complexity of the brain acceptance and processing are both higher, so that the brain function is relatively intact.…”

Declining financial capacity in mild cognitive impairment

“…It measures procedural skills that are likely mediated through executive abilities, whereas task 4a measures factual knowledge and is likely mediated by long-term semantic memory. These procedural declines are consistent with the executive function deficits exhibited by patients with amnestic MCI, [23][24][25][26] and the strong ties between executive function and functional abilities. 18,[27][28][29][30][31][32][33] Checkbook management (domain 4) item responses were further analyzed to describe common errors made by MCI converter participants.…”

The Diagnostic Value of Controlled Oral Word Association Test-FAS and Category Fluency in Single-Domain Amnestic Mild Cognitive Impairment

“…Sperling et al [37] state that cognitive decline in non-memory domains often accompanies declines in episodic memory which highlights the need to identify neuropsychological tests that will aid in identifying individuals in the earliest stages of cognitive decline. This statement is supported by longitudinal results from Johnson et al [38] and Small and Bäckman [39], showing that decline in cognitive domains other than memory is detectable in preclinical AD, and also by Kramer et al [40] and Ribeiro et al [41] who also demonstrated that non-memory domains show decline in individuals with MCI.…”