Awareness of memory deficits in subjective cognitive decline, mild cognitive impairment, Alzheimer's disease and Parkinson's disease

Anosognosia or reduced awareness of cognitive and functional problems is a known clinical phenomenon in patients experiencing cognitive decline. It is common even in mild dementia syndromes and is often reported to increase with clinical disease progression (Aalten et al., 2006). More recently it also has been described in older adults with cognitive-impairment-no-dementia (CIND) and mild cognitive impairment (MCI) (Greenop et al., 2011; Maki et al., 2012). The clinical significance of awareness is a topic of controversy in the literature and determining its biological correlates in brain function and structure is an ongoing challenge (Zamboni et al., 2013; Ford et al., 2014).