Anosognosia for Memory Impairment in Addiction: Insights from Neuroimaging and Neuropsychological Assessment of Metamemory

Abstract

In addiction, notably, Alcohol Use Disorder (AUD), patients often have a tendency to fail to acknowledge the reality of the disease and to minimize the physical, psychological, and social difficulties attendant to chronic alcohol consumption. This lack of awareness can reduce the chances of initiating and maintaining sobriety. Presented here is a model focusing on compromised awareness in individuals with AUD of mild to moderate cognitive deficits, in particular, for episodic memory impairment—the ability to learn new information, such as recent personal experiences. Early in abstinence, alcoholics can be unaware of their memory deficits and overestimate their mnemonic capacities, which can be investigated with metamemory paradigms. Relevant neuropsychological and neuroimaging results considered suggest that the alcoholics’ impairment of awareness of their attenuated memory function can be a clinical manifestation explained mechanistically by neurobiological factors, including compromise of brain systems that result in a mild form of mnemonic anosognosia. Specifically, unawareness of memory impairment in AUD may result from a lack of personal knowledge updating attributable to damage in brain regions or connections supporting conscious recollection in episodic memory. Likely candidates are posterior parietal and medial frontal regions known to be integral part of the Default Mode Network (DMN) and the insula leading to an impaired switching mechanism between the DMN and the Central-Executive Control (i.e., Lateral Prefronto-Parietal) Network. The cognitive concepts and neural substrates noted for addictive disorders may also be relevant for problems in self-identification of functional impairment resulting from injury following war-related blast, sport-related concussion, and insidiously occurring dementia.

Executive Functions, Memory, and Social Cognitive Deficits and Recovery in Chronic Alcoholism: A Critical Review to Inform Future Research

“…The tendency to choose short‐term gratification at the expense of long‐term consequences suggests that alcoholics may suffer from myopia for the future (Camchong et al., ; Le Berre et al., ). This “myopia” may include patients’ awareness that the problems arise from their substance abuse and keep them in denial (Verdejo‐Garcia and Perez‐Garcia, ) or in a form of anosognosia (Le Berre and Sullivan, ) about their disorder.…”

“…It has been consistently reported that treatment‐seeking AUD individuals have detectable cognitive impairment, often involving executive dysfunction and memory deficits (see reviews Oscar‐Berman et al., ; Sullivan et al., ). Recently, new considerations to expand the understanding of functional impairment in alcoholism have included the investigation of metacognition (the ability to accurately assess one's own cognitive abilities), especially metamemory processes, together with emotional and social cognitive abilities (Bora and Zorlu, ; Le Berre and Sullivan, ; Maurage et al., ; Uekermann and Daum, ). In particular, research efforts are warranted for understanding the complex interactions among executive, memory, and social and emotional processing abilities.…”

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

“…Consequently, it could compromise the processing and resolution of uncertainty by setting up more effortful executive processes useful to retrieve information about the actual episodic memory experience and to support the cognitive comparator mechanisms to enhance the detection of a memory failure. By default, alcoholics may base their memory predictions only on the subjective and affective self-referential information stored in their personal database [cf., (Le Berre & Sullivan, 2016; Morris & Mograbi, 2013)] rather than on an objective assessment based on online memory monitoring processes. However, according to our previous study conducted in the same group of alcoholics, the subjective representation of the alcoholics' actual memory functioning, i.e., their personal database, may not have been completely updated over time and would only reflect their memory skills at some time earlier in life, perhaps before or at the beginning of their alcoholism onset (Le Berre et al, 2016).…”

“…The dissociation between objective abilities and subjective awareness of those abilities can be characterized as a mild form of anosognosia and have implications for readiness and acceptance of cognitive rehabilitation efforts (Le Berre & Sullivan, 2016). …”

“…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). …”