One in seven Aussie mums (16 per cent) will experience the debilitating symptoms of peri-natal and post-natal depression.
While research into its cause continues, Western Sydney researchers have found evidence that infants of mothers with post-natal depression (PND) are less communicative than peers of non-depressed mothers.
Other research has shown that babies of mums who suffered with PND were more likely to show poor cognitive function, less school readiness, poor reasoning skills and a lack of problem solving skills.
After being awarded a South West Sydney Research Seed Grant, Dr Christa Lam-Cassettari, a post-doctoral researcher with the MARCS Institute for Brain, Behaviour and Development at Western Sydney University, (and her collaborators at UNSW and Karitane), conducted a pilot study that investigated the effect of maternal depression on the communication of children.
Dr Lam-Cassettari said there is evidence that some of the long term effects of PND were that it adversely affected emotion regulation in infants, predisposed pre-teens to depression, and resulted in externalised behavioural issues in pre-teens and adolescents.
"But there is little understanding of how PND affects speech and language development in early childhood," she said.
"What we know is that PND hinders bonding and interaction between mothers and their newborns, depriving those children of the opportunity to communicate.
"What our research found was that mothers with post-natal depression tend to communicate infrequently with their infants, in a monotonal manner and in a low pitch.
"As a group these mothers also spoke less to their young infants overall and didn't engage in the same amount of interactive communication such as speaking in a sing-song tone, playing games and singing – all of which have been shown to have significant benefits on an infant's cognitive development and their language acquisition skills."
This research study was aimed at understanding how psychosocial factors influence early speech and language development The study tested differences in the quality and quantity of speech of mothers to their pre-speech infants (aged 4-6 months) in two western Sydney groups, one group with PND mothers and a control group of non-depressed mothers.
Dr Lam-Cassettari she her research findings indicated that infant language development flourished when there was positive reinforcement between mother and child.
"We know from previous research that until 14 months of age, babies actually preferred to listen to infant directed speech (IDS) over adult directed speech," she said.
"IDS has been found to aid language development, facilitate word recognition through exaggerated vowel sounds and pronunciation, and facilitate good speech discrimination."
"This study was intended to provide a foundation for examining the longer-term effects of post-natal depression on infant language and provide a direct opportunity to perform further studies that will bridge current gaps in clinical practice."
Dr Lam-Cassettari said she was hoping to look at more longitudinal effects by taking vocabulary measures of infants at 12 months in a new group of infants with PND mums and non PND mums.
It is important to note that PND is involuntary, and it is a serious condition that should be treated by a medical professional.
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