Specific features of memory consolidation and reconsolidation in older individuals with vision and hearing impairments

Abstract

Sensory impairments (visual and auditory) reduce quantity and quality of the information input. The associated memory loss can be classified as intrinsic decline in memory functionalities or mere physiological effect of sensory deprivation. This study aimed to specify this issue by analyzing memory consolidation and reconsolidation processes in older people with sensory deficits. The study enrolled 65–75 year-old individuals (n = 61) distributed into four groups: patients with unilateral sensorineural hearing loss (n = 17); patients with bilateral sensorineural hearing loss (n = 14); patients with visual impairment (n = 19); and patients with combined sensory deficits (n = 11). The methods included Luria’s auditory-verbal (“10 words”) and visual memory tests and Bartlett’s experimental procedure. A decrease in memory volume for auditory-verbal and visual-figurative short-term memories was observed in all groups. The results reveal significant adverse dynamics of qualitative and quantitative indicators for memory consolidation and reconsolidation processes, associated with decreased volume of short-term memories, both auditory-verbal and visual-figurative. Based on these findings, we conclude that consolidation and reconsolidation efficiency depends on proper accommodation of the newly incoming information to already memorized modules (previous experience) and requires dosing of the newly incoming information in order to preserve its integrity at the stage of consolidation.