Differential compromise of prospective and retrospective metamemory monitoring and their dissociable structural brain correlates

Abstract

Metamemory refers to personal knowledge about one’s own memory ability that invokes cognitive processes relevant to monitoring and controlling memory. An impaired monitoring system can potentially result in unawareness of symptoms as can occur in addiction denial. Monitoring processes can be assessed with prospective measures such as Feeling-Of-Knowing (FOK) judgments on prediction of future recognition performance, or retrospective confidence judgments (RCJ) made on previous memory performance. Alcoholic patients with amnesia showed poor FOK but intact RCJ. The neuropsychological continuum from mild to moderate deficits in nonamnesic to amnesic alcoholism raised the possibility that alcoholics uncomplicated by clinically-detectable amnesia may suffer anosognosia for their mild memory deficits. Herein 24 abstinent alcoholics and 26 age-matched controls completed an episodic memory paradigm including prospective FOK and retrospective RCJ monitoring measures and underwent 3T structural magnetic resonance imaging. Alcoholics were less accurate than controls in recognition and in assessing their future recognition performance, which was marked by overestimation, but were as accurate as controls on confidence ratings of actual recognition performance. Examination of brain structure-function relations revealed a double dissociation where FOK accuracy was selectively related to insular volume, and retrospective confidence accuracy was selectively related to frontolimbic structural volumes. Impaired FOK with intact RCJ was consistent with mild anosognosia and suggested evidence for neuropsychological and neural mechanisms of unawareness in addiction.

Deviant functional activation and connectivity of the right insula are associated with lack of awareness of episodic memory impairment in nonamnesic alcoholism

“…Using an episodic FOK paradigm, a recent paper reported that structural integrity of the right insula supported memory awareness in a mixed group, which included patients with mild Alzheimer's disease and cognitively healthy older adults (Cosentino et al, 2015). Similarly, we found that FOK accuracy was selectively related to volumes of the insula in the uncomplicated alcoholics involved in the present study (Le Berre et al, 2016). Because the insula has been identified as a critical neural substrate of multiple components of self-awareness (Craig, 2009; Schmitz & Johnson, 2007), we posited that prospective episodic FOK implicates online memory monitoring mechanisms and additional self-referential processes to generate accurate future estimations.…”

“…Further, we explored whether these brain activation and functional connectivity patterns during predictions of future recognition performance could contribute to subsequent memory performance, especially because efficient metamemory skills are implicated in efficient use of memory skills in daily life activities. Previously, we demonstrated that the insula was a key selective structural brain substrate of FOK accuracy in sober alcoholics participating in the present study (Le Berre et al, 2016). Herein, we used functional imaging to test the hypothesis that attenuated activation of the insula and compromised insula functional connectivity would contribute to overestimation of memory performance by uncomplicated alcoholics.…”

“…Our previous studies have shown that alcoholics exhibited a tendency to overestimate their prediction of future episodic memory performance, believing themselves capable of accurately recognizing information when they subsequently failed to do so. We have assumed that this cognitive dissociation of intact RCJ with impaired FOK in uncomplicated alcoholism is consistent with a secondary mnemonic anosognosia (Le Berre et al, 2016). In other words, when alcoholics fail to consolidate newly updated information about their memory abilities into their semantic and autobiographical personal long-term knowledge database, they then compare their current memory functioning to outdated self-beliefs (Le Berre & Sullivan, 2016; Morris & Mograbi, 2013).…”

“…Although typically associated with the profound amnesia of Korsakoff's Syndrome, limited awareness can be observed in alcoholics without neurological complication for their episodic memory deficits, a metamemory disorder (Le Berre et al, 2016; Le Berre et al, 2010). The limited awareness of mnemonic impairment may promote unawareness of functional compromise and undermine treatment efforts by engendering the false belief that nothing is wrong to be fixed.…”

“…Abstinent alcoholics have been reported to make accurate judgments in retrospective confidence ratings of actual recognition performance (i.e., Retrospective Confidence Judgment, RCJ) but to be inaccurate in assessing future recognition performance for episodic information (i.e., Feeling-Of-Knowing judgments, FOK) (Le Berre et al, 2016; Le Berre et al, 2010). Our previous studies have shown that alcoholics exhibited a tendency to overestimate their prediction of future episodic memory performance, believing themselves capable of accurately recognizing information when they subsequently failed to do so.…”