The neuropsychological expression of ARBD is marked by heterogeneity in the extent (severity) and type (component) of deficit, and not all individuals with uncomplicated alcoholism exhibit impairments in all the functions described above.33 Similarly, not all patients with KS have permanent amnesia.35 This heterogeneity suggests that the functions affected by chronic alcohol consumption are dissociable and supported by different neural systems.36 One study examined the component processes of episodic memory (memory of auto biographical events) and working memory (the ability to hold information ‘online’ while doing complex tasks) in individuals with uncomplicated alcoholism and patients with alcoholism and KS. The former could generally be differentiated from the latter via performance on tests of episodic memory (that is, the two groups showed graded impairment in episodic memory), despite significant overlap in performance on working-memory tasks between the two groups (that is, continuous impairment was seen between the two groups).37 On the basis of these findings, the study’s researchers suggested that impairment of episodic memory was the result of the untoward effects of alcohol on the Papez (limbic) circuit and was exacerbated
