Alzheimer's disease can spare local metacognition despite global anosognosia: Revisiting the confidence–accuracy relationship in episodic memory

Abstract

Alzheimer’s Disease (AD) can impair metacognition in addition to more basic cognitive functions like memory. However, while global metacognitive inaccuracies are well documented (i.e., low deficit awareness, or anosognosia), the evidence is mixed regarding the effects of AD on local or task-based metacognitive judgments. Here we investigated local metacognition with respect to the confidence-accuracy relationship in episodic memory (i.e., metamemory). AD and control participants studied pictures of common objects and their verbal labels, and then took forced-choice picture recollection tests using the verbal labels as retrieval cues. We found that item-based confidence judgments discriminated between accurate and inaccurate recollection responses in both groups, implicating relatively spared metamemory in AD. By contrast, there was evidence for global metacognitive deficiencies, as AD participants underestimated the severity of their everyday problems compared to an informant’s assessment. Within the AD group, individual differences in global metacognition were related to recollection accuracy, and global metacognition for everyday memory problems was related to task-based metacognitive accuracy. These findings suggest that AD can spare the confidence-accuracy relationship in recollection tasks, and that global and local metacognition measures tap overlapping neuropsychological processes.

Relating pessimistic memory predictions to Alzheimer's disease brain structure

“…The few studies that have examined postretrieval metacognitive judgments (JOC) in AD patients suggested that such metacognitive processes can be relatively preserved (Gallo et al, 2012;Moulin et al, 2003), although it might depend on task-demands and the stage of dementia (Dodson et al, 2011). In contrast, predictive metacognitive judgments (FOK) have been found to be altered in AD-like pathology with AD patients and MCI patients tending to overestimate their abilities (Souchay et al, 2002;Perrotin et al, 2007).…”

Awareness of executive functioning as a diagnostic tool for mild cognitive impairment and Alzheimer's disease.

“…However, poor episodic memory does not guarantee poor awareness, as AD patients may use familiarity to retain awareness even as memory performance declines. This phenomenon has been observed for memory awareness and broad metacognition (Gallo et al, 2012;Pannu & Kaszniak, 2005;Souchay, 2007) but not specifically in executive functioning awareness (see discussion of the CAM model below).…”

“…The authors argued that, because more basic aspects of metamemory are spared in mild AD, these patients may use familiarity more often in their daily judgments than detailed recollection. This could result in inaccurate judgments, which are unlikely to be updated to their long-term personal knowledge (Gallo, Cramer, Wong, & Bennett, 2012).…”

“…The preliminary evidence suggests that executive and/or mnemonic anosognosia emerges before primary anosognosia among AD patients (Agnew & Morris, 1998;Gallo et al, 2012;Hannesdottir & Morris, 2007). Therefore, it may be most useful to examine their associated components of the CAM in order to detect changes between normal cognition and MCI, as well as between MCI and AD.…”

“…Several studies show support for executive functioning components as relevant to anosognosia, either through distinctions in testing (Gallo et al, 2012) or neurobiological differences Johnson et al, 2007). Many studies also suggest that awareness should be interpreted as a multidimensional construct (Ansell & Bucks, 2006;Hannesdottir & Morris, 2007;Mimura & Yano, 2006).…”