Selective recall deficits for heterogeneous associations in detoxified individuals with alcohol use disorder

Aim: Alcohol use disorder (AUD) has been associated with recognition memory deficits. However, it remains unclear whether these deficits occur at the general recognition memory level or whether they selectively affect its subcomponents. Evidence suggests that recognition memory deficits may vary according to the heterogeneity of memory stimuli. Our aim was to investigate stimuli pair-dependent recognition memory deficits in AUD, using a cued recall task including homogeneous and heterogeneous stimuli pairs. Methods: Twenty-three patients with AUD (days since last alcohol consumption: 11.70 ± 10.20) and 23 healthy controls (HC) underwent a neuropsychological examination tapping attention, verbal fluency, logical, working and long-term memory, and a recognition and recall task involving both homogeneous (tool-tool) and heterogeneous (tool-scene, tool-animal) stimuli pairs. Group (AUD-HC) by condition (tool-tool, tool-scene, tool-animal) ANOVAs were performed on all neuropsychological indices. Results: In the neuropsychological examination, AUD individuals showed deficits in delayed recall and faster reaction times compared with HC. The administration of the recognition and recall task revealed specific performance decreases in cued recall occurring in the whole sample (AUD + HC) for heterogeneous (tool-scene, tool-animal) pairs compared with homogeneous pairs. Within this pattern, AUD patients showed a lower cued recall rate than HC only for tool-animal pairs. Conclusions: Our results support the existence of specific recall/recollection deficits in AUD which occurred for heterogeneous, but not for homogeneous stimuli pairs. This finding calls for further neuroimaging investigations aimed at investigating the neurobiological substrate of (i) different recognition memory subcomponents, and (ii) the processing of stimuli with different degree or type of heterogeneity.