The study conducted by researchers at University of California, Irvine (UCI) in US implies that when mothers are nurturing their infants, numerous everyday interruptions - even those as seemingly harmless as phone calls and text messages - can have a long-lasting impact.

The researchers studied the emotional outcomes of adolescent rats reared in either calm or chaotic environments and used mathematical approaches to analyse the mothers' nurturing behaviours.

Despite the fact that quantity and typical qualities of maternal care were indistinguishable in the two environments, the patterns and rhythms of care differed drastically, which strongly influenced how the rodent pups developed.

Specifically, in one environment, the mothers displayed 'chopped up' and unpredictable behaviours.

During adolescence, their offspring exhibited little interest in sweet foods or peer play, two independent measuresof the ability to experience pleasure. Known as anhedonia, the inability to feel happy is often a harbinger of later depression.

The study shows that consistent rhythms and patterns of maternal care seem to be crucially important for the developing brain, which needs predictable and continuous stimuli to ensure the growth of robust neuron networks.

The findings were published in the journal Translational Psychiatry.