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University of Wisconsin–Madison, Madison, Wisconsin, United States
Journal of the International Neuropsychological Society (Impact Factor: 2.96). 06/2007; 13(3):450-61. DOI: 10.1017/S1355617707070488
Source: PubMed


Awareness of cognitive dysfunction shown by individuals with Mild Cognitive Impairment (MCI), a condition conferring risk for Alzheimer's disease (AD), is variable. Anosognosia, or unawareness of loss of function, is beginning to be recognized as an important clinical symptom of MCI. However, little is known about the brain substrates underlying this symptom. We hypothesized that MCI participants' activation of cortical midline structures (CMS) during self-appraisal would covary with level of insight into cognitive difficulties (indexed by a discrepancy score between patient and informant ratings of cognitive decline in each MCI participant). To address this hypothesis, we first compared 16 MCI participants and 16 age-matched controls, examining brain regions showing conjoint or differential BOLD response during self-appraisal. Second, we used regression to investigate the relationship between awareness of deficit in MCI and BOLD activity during self-appraisal, controlling for extent of memory impairment. Between-group comparisons indicated that MCI participants show subtly attenuated CMS activity during self-appraisal. Regression analysis revealed a highly significant relationship between BOLD response during self-appraisal and self-awareness of deficit in MCI. This finding highlights the level of anosognosia in MCI as an important predictor of response to self-appraisal in cortical midline structures, brain regions vulnerable to changes in early AD.

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Available from: Carey Gleason, Aug 28, 2014
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    • "Part of the reason for this left-hemisphere assymetry may be that SA often recruits IS processes located in the LIFG (Morin and Hamper, 2012). Several researchers emphasize the importance of cortical midline structures (CMS; D'argembeau et al., 2008; Northoff, 2014; Ries et al., 2007; Summerfield, Hassabis and Maguire, 2009). Moran and colleagues (2013) suggest that CMS are specialized for representing any type of social information, including the self; they are also responsible for the direction of our thought processes on a moment-to-moment basis and represent a hub integrating information from disparate neural processing systems into a ―conscious workspace‖ (Baars, 2002). "
    Theory of Mind: Development in Children, Brain Mechanisms and Social Implications., Edited by Elizabeth Sherwood, 01/2015: pages 43-113; Nova Publishers.., ISBN: 978-1-63463-856-2
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    • "On the contrary, very few data are available for MCI. The sparse results on this topic tend to confirm the role of frontal, prefrontal and temporal areas (Ries et al., 2007; Vogel, Hasselbalch, Gade, Ziebell, & Waldemar, 2005; Zamboni et al., 2013), whose deterioration in MCI subjects is frequently described as characteristic of a subsequent conversion to AD. Unfortunately, some of the cited studies did not focus only on MCI patients, but included other diagnostic groups. "
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    ABSTRACT: Background: Awareness of cognitive deficits may be reduced in mild cognitive impairment (MCI). This may have a detrimental effect on illness course and may be a predictor of subsequent conversion to AD. Although neuropsychological correlates have been widely investigated, no evidence of a neuroanatomical basis of the phenomenon has been reported yet. This study was aimed at investigating the neuroanatomical correlates of deficit awareness in amnestic MCI to determine whether they constitute risk factors for conversion to AD. Method: A sample of 36 first-diagnosis amnestic MCI patients were followed for five years. At the first diagnostic visit they were administered an extensive diagnostic and clinical procedure and the Memory Insight Questionnaire (MIQ), measuring a total index and four sub-indices, to investigate awareness of deficits in dementia; they also underwent a high resolution T1-weighted Magnetic Resonance Imaging (MRI) investigation. Grey matter brain volumes were analysed on a voxel-by-voxel basis using Statistical Parametric Mapping 8. Data of 10 converter patients (CONV) and those of 26 non converter patients (NOCONV) were analysed using multiple regression models. Results: At baseline, self-awareness of memory deficits was poorer in CONV compared to NOCONV. Furthermore, reduced awareness of cognitive deficits in CONV correlated with reduced grey matter volume of the anterior cingulate (memory deficit awareness), right pars triangularis of the inferior frontal cortex (memory deficit awareness) and cerebellar vermis (total awareness), whereas in NOCONV it correlated with reduced grey matter volume of left superior (total awareness) and middle (language deficit awareness) temporal areas. Further, at baseline self-awareness of memory deficits were poorer in CONV than in NOCONV. Conclusions: Defective awareness of cognitive deficits is underpinned by different mechanisms in CONV and NOCONV amnestic MCI patients. Our data support the hypothesis that poor awareness of cognitive deficit is a predictor of subsequent conversion to AD.
    Cortex 12/2014; 61:183-95. DOI:10.1016/j.cortex.2014.10.010 · 5.13 Impact Factor
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    • "The frontal or parietal cortex may also be linked to self-perceived memory changes as suggested in the existing literature on anosagnosia (i.e., awareness of cognitive abilities and impairment) [for review; 21]. Functional imaging studies suggest MCI individuals with poor awareness of their own cognitive ability have altered metabolism in the medial frontal [22], parietotemporal [23] and posteriomedial [24], and posterior cingulate[22] regions. Volumetric brain analyses suggest that more unawareness of one's cognitive ability is related to smaller medial frontal cortex in MCI [25]. "
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    ABSTRACT: Background: A cognitive concern from the patient, informant, or clinician is required for the diagnosis of mild cognitive impairment (MCI); however, the cognitive and neuroanatomical correlates of complaint are poorly understood. Objective: We assessed how self-complaint relates to cognitive and neuroimaging measures in older adults with MCI. Method: MCI participants were drawn from the Alzheimer's Disease Neuroimaging Initiative and dichotomized into two groups based on the presence of self-reported memory complaint (no complaint n = 191, 77 ± 7 years; complaint n = 206, 73 ± 8 years). Cognitive outcomes included episodic memory, executive functioning, information processing speed, and language. Imaging outcomes included regional lobar volumes (frontal, parietal, temporal, cingulate) and specific medial temporal lobe structures (hippocampal volume, entorhinal cortex thickness, parahippocampal gyrus thickness). Results: Linear regressions, adjusting for age, gender, race, education, Mini-Mental State Examination score, mood, and apolipoprotein E4 status, found that cognitive complaint related to immediate (β = -1.07, p < 0.001) and delayed episodic memory performances assessed on a serial list learning task (β = -1.06, p = 0.001) but no other cognitive measures or neuroimaging markers. Conclusions: Self-reported memory concern was unrelated to structural neuroimaging markers of atrophy and measures of information processing speed, executive functioning, or language. In contrast, memory self-complaint related to objective verbal episodic learning performance. Future research is warranted to better understand the relation between cognitive complaint and surrogate markers of abnormal brain aging, including Alzheimer's disease, across the cognitive aging spectrum.
    Journal of Alzheimer's disease: JAD 10/2014; 44(1). DOI:10.3233/JAD-140636 · 4.15 Impact Factor
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