Persistence of implicit recognition in neurocognitive diseases

BackgroundRecognition abilities are often considered severely impaired in the advanced stages of Alzheimer's disease and related neurocognitive diseases. However, implicit forms of recognition, supported by emotional and relational processes, may remain preserved despite profound cognitive decline.ObjectiveThis study aimed to explore implicit recognition in older adults with advanced neurocognitive diseases through repeated interactions with an unfamiliar experimenter in emotionally modulated contexts.MethodsForty residents of long-term care facilities were randomly assigned to one of two experimental conditions: a positive emotional condition (warm interaction and emotional expressions) or a neutral emotional condition (detached and factual interaction). An 11-session protocol was designed to capture the progressive emergence of recognition behaviors-verbal and nonverbal, spontaneous or elicited-toward the experimenter. Behavioral responses were analyzed across sessions using statistical analyses examining recognition type, emotional condition, and temporal progression.ResultsA main effect of recognition type was observed, with verbal responses, particularly those elicited by prompts, being predominant. The positive emotional condition significantly enhanced the expression of implicit recognition behaviors. A significant temporal progression was also identified, peaking at session 11, suggesting implicit learning across repeated exposures.ConclusionsDespite advanced neurocognitive diseases, older adults appear to retain the capacity for new learning mediated by implicit memory. Repeated exposure and emotionally meaningful interactions foster familiarity with the experimenter and highlight the persistence of relational and affective competencies. These findings emphasize the role of affective memory in sustaining interpersonal connections and support emotionally attuned human interaction as a valuable therapeutic approach in institutional care.