Monash study reframes baby brain: new mother's memories are just as good as non-mothers

It’s sometimes called Baby Brain – the experience of cognitive deficits, or memory loss, in the months before and after having a baby. Now Monash researchers have conducted a study that has, for the first time, revealed that new mums don’t get “baby brain”, but they may perceive cognitive deficits because they are overworked, tired, anxious and acutely aware that memory lapses can have serious consequences with the introduction of a new life into the family

Around 80% of expectant mothers report what is also called “pregnancy-brain”, which is characterised by forgetfulness. While there are some subtle memory deficits found in pregnancy, there have been few studies on memory in new mothers, “and no one really knows whether pregnancy-related “brain fog”, as it is also called, resolves after birth,” Dr Jamadar said.

Led by Dr Winnie Orchard and Associate Professor Sharna Jamadar, from the Turner Institute for Brain and Mental Health, and published in the Journal for Women’s Health, the study looked at cognition in 86 women – 43 first-time mothers one year post-partum and 43 non-mothers.

In the Monash study, on tests of verbal memory, working memory, processing speed (the time it takes for cognitive computation) or theory of mind (the ability to understand the reasons behind others’ behaviour) mothers and non-mothers didn’t differ. However – mothers significantly reported worse subjective memory than non-mothers.

To drill down into the causes of this discrepancy – Dr Orchard & Associate Professor Jamadar looked at the participants’ relationships between subjective memory, objective memory and well-being. “Essentially we wanted to test each woman’s actual memory, their belief in how well they remember things, and how it relates to their overall sense of well-being such as sleep, anxiety and depression,” Dr Orchard said.

The study found, despite the two groups showing no differences on objective measures of memory (i.e. their capacity to recall numbers, objects etc.), mothers self-reported significantly worse memory than non-mothers. “Despite having just as good a memory as non-mothers, new mums believed their memory was worse,” Associate Professor Jamadar said.

According to the authors, the increased cognitive load associated with having a new baby likely leads to more opportunities to be forgetful. “For example, leaving the house with a one-year-old in tow requires a new mother to remember a host of items – nappy bag, dummy, a favourite toy, snacks, a change of clothes, a bottle – the list goes on,” Dr Orchard stated.

Memory errors in the postpartum period also carry heavier consequences (e.g., an unsettled baby, a sleepless night, in the extreme – harm to the baby), making memory lapses more salient, according to A/Prof Jamadar. “Pregnancy and early motherhood may make women more attuned to their functioning, through a higher sensitivity to minor memory or concentration lapses, which perhaps would have otherwise been ignored, or considered inconsequential before pregnancy,” she said.

Dr Orchard noted, “We speculate that the increased cognitive load of daily life in early motherhood represents a cognitive challenge, with higher consequences for memory lapses, which encourages mothers to evaluate and re-evaluate their subjective memory regularly.”

The study concluded that a new mum’s perception of her memory, or that she has Baby Brain, is influenced by an increased cognitive load, a heightened awareness of memory lapses and poorer well-being.

About the Turner Institute

The Turner Institute for Brain and Mental Health was established in 2015 by Monash University following a philanthropic gift from the David Winston Turner Endowment Fund, enabling ground-breaking research, training and treatment solutions for brain and mental health conditions.