Short-term social recognition memory deficit and atypical social and physiological stressor reactivity in seizure-susceptible El mice

Social investigation times (mean±SEM) on the first and second trial of Experiment 1 in El and ddY mice tested in the social recognition memory task with familiar juveniles. Experimental mice were exposed to the same juvenile on each of the two trials so that the juvenile was familiar on Trial 2. The results reflect poor sociability and deficient short term working memory performance for El mice in contrast to relatively greater sociability and capable memory performance for ddY controls. ^*p<0.05 relative to the Trial 1.

Social investigation difference scores (mean±SEM) in El and ddY mice tested in the social recognition memory task of Experiment 1 with familiar and unfamiliar juveniles. In the familiar juvenile condition, experimental mice were exposed to the same juvenile on each of the two trials so that the juvenile was familiar on Trial 2. In the unfamiliar juvenile condition, experimental mice were exposed to novel juveniles on both trials. The results reflect capable short term working memory performance for ddY controls without non-specific performance or motivational deficiencies in contrast to the poor working memory performance for El mice. ^*p<0.05 relative to a mean of zero.

Social investigation times (mean±SEM) on the first trial in El and ddY mice tested in the social recognition memory task of Experiment 1. Experimental mice were exposed to an unfamiliar juvenile during a 4min test. The results reflect enhanced investigation of juveniles by ddY females relative to ddY males; no such difference emerged in the El strain. ^*p<0.05 relative to ddY males.

Social investigation times (mean±SEM) on the first and second trial of Experiment 2 in control or salt-loaded El and ddY mice tested in the social recognition memory task with familiar juveniles. Experimental mice were exposed to the same juvenile on each of the two trials so that the juvenile was familiar on Trial 2. The results reflect poor sociability and short term working memory performance for El mice in contrast to capable memory performance for ddY controls. Social recognition memory performance in ddY mice was abolished, however, by the salt-loading treatment. ^*p<0.05 relative to Trial 1.