Morphological Cerebral Correlates of CERAD Test Performance in Mild Cognitive Impairment and Alzheimer's Disease

Abstract

The objective of this study was to investigate the association between structural cerebral changes and neuropsychological deficits in mild cognitive impairment (MCI) and Alzheimer's disease (AD). Sixty patients with MCI, 34 patients with mild to moderate AD, and 32 healthy controls underwent both extensive neuropsychological assessment (CERAD test battery) and high-resolution structural magnetic resonance imaging. We used optimized voxel based morphometry to investigate (i) differences in gray matter density between the three aforementioned groups and (ii) the putative relations of CERAD test performance with atrophic brain changes. When compared to the healthy controls, the AD patients and, to a lesser extent, patients with MCI showed significant density losses predominantly in the medial temporal lobe. Deficits in verbal fluency and word finding were significantly correlated with left fronto-temporal and left temporal (including hippocampal) changes, respectively. Decreased scores in immediate and delayed recall and in delayed recognition were associated with several cortical and subcortical sites including the parahippocampal and posterior cinguli gyri, the right thalamus, and the right hippocampus, whereas deficits in constructional praxis and constructional praxis recall referred to sites in the left thalamus and cerebellum, and the temporal cortices (bilaterally), respectively. Our findings lend further support for medial temporal lobe degeneration in MCI and AD and demonstrate that cognitive deficits as assessed on the CERAD do not simply refer to specific changes in discrete cerebral sites but rather reflect morphological alterations in widespread networks.

Regional Cortical Thickness and Subcortical Volume Changes Are Associated with Cognitive Impairments in the Drug-Naive Patients with Late-Onset Depression

“…They suggested that depression patients might compensate for their dysfunctional prefrontal 'search' mechanisms by using more direct strategies to obtain entrance to their verbal hippocampal memory systems. In addition, significant correlations between the hippocampal volumes and semantic fluency task were observed in the patients with MCI and AD (Dos Santos et al, 2011;Gleissner and Elger, 2001). A previous voxel-based lesion symptom mapping study on the stroke patients showed that the scores of semantic fluency task were correlated with the putamen and the insula (Baldo et al, 2006).…”

Correlation between gray matter volume in the temporal lobe and depressive symptoms in patients with Alzheimer's disease

“…Subjects were categorized based on K-MMSE score (less than 20 for AD, between 20 and 25 for MCI, and greater than 25 for the control group) [18]. After screening test, we also evaluated their cognitive function using the K-CERAD, which assesses verbal fluency, naming, immediate/delayed recall, constructional praxis, and constructional praxis recall, and this measure was also used to identify AD or MCI in dividing line patients, such as K-MMSE score 20 or 25 [5]. Those subjects were further categorized into each group based on K-CERAD score: one item failure MCI group, and more than two item failures AD group.…”

Neurocognitive Deficits and Effects of Cognitive Reserve in Mild Cognitive Impairment

“…Declarative memory deficits involving verbal memory and LM constitute the hallmark of MCI and AD [12,46] and were demonstrated in the vast majority of patients with MCI and all patients with manifest AD who showed significant deficits in LM (81.5 and 100%) and verbal memory (84.7 and 100%), respectively. As described in a wealth of studies, these deficits refer to changes of the hippocampus and other structures of the medial temporal lobe, which can already be demonstrated in MCI and early AD [47], as cited in Schröder and Pantel [1].…”

“…A much higher frequency was established for the multiple-domain amnestic subtypes, mainly due to the high frequency of executive deficits [11]. This is of particular importance as the latter can be referred to the frontal cortices, which are generally assumed not to be primarily involved in AD [12,13]. …”