Effects of early social deprivation on emotionality in rats.

Following parturition, 95 male Holtzman albino rat pups were separated from their mothers and randomly assigned to rearing conditions (a) with mother and peers, (b) with mother without peers, (c) in incubators with peers, or (d) in incubators in isolation. At 65 days of age Ss were tested daily in an open field for 3 min. over 6 consecutive days. At 113 days of age, Ss were restrained and presented a mild auditory stimulus and subsequently a noxious shock stimulus while heart rate recordings were taken. Higher emotionality in maternally-deprived Ss was evidenced in longer emergence latencies, lower ambulatory scores, and higher urination frequencies in the open field. Maternally-deprived Ss also gave larger heart rate responses to auditory and shock stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)