The largest and most comprehensive study of memory and cognition in new parents has found no evidence for "baby brain" in mums and dads.
New mums often complain about having "baby brain", where memory and cognition become vague and unreliable. Now a Monash University study – the largest ever done comparing cognitive ability in new mums and dads – has unequivocally found no evidence that "baby brain" reflects underlying problems with cognition that result from becoming a parent.
In a study published in the journal, Cortex, and led by Navyaan Siddiqui and Dr Kelsey Perrykkad from the Cognitive Neuroimaging Lab at the Turner Institute for Brain and Mental Health in the Monash School of Psychological Sciences, researchers examined cognitive differences in 150 birth-giving mothers and 150 non-birth-giving fathers up to two years after the birth of their baby.
The study found – using a comprehensive battery of cognitive assessments – that both mums and dads showed similar performance to non-parent (male and female) controls on all cognition measures, "suggesting the absence of so-called 'baby brain' effects," Dr Perrykkad said.
As an explanation of the common stereotype of "baby brain", the researchers found a gender bias, with male non-fathers self-reporting better subjective memory than all other groups. However, according to Navyaan Siddiqui, lead author on the paper, "this self-promotion bias appeared to be lost in fathers, driven by lack of sleep".
Strikingly, there was no effect of time postpartum on any cognitive measure, with parents' ability on cognitive tests remaining the same, regardless of the age of the baby, up to two years, when it is assumed that sleep deprivation would be reduced.
While there is evidence of subtle decrements in cognition during pregnancy, according to Dr Perrykkad, "the evidence is inconsistent about the presence of an objective measurable decline in cognitive function during the postpartum period, with studies revealing a potential mismatch between the self-reported parental experience and objective measures of cognitive change," she said.
Navyaan Siddiqui said that – before the study – they expected that mothers and fathers would show subjective and objective reduction in cognition compared to non-parents.
"We expected that there would be little to no difference between the new mums and dads on account of their shared environment post birth and we also expected that cognition would improve in parents with increased time postpartum," he said.
Dr Perrykkad continued: "So why do new parents, especially new mothers, commonly report experiences of baby brain? It is important not to dismiss what new parents are telling us. When we do find evidence for baby brain, it is more related to sleep and wellbeing than a true objective decline in cognition. This indicates it is just as important as ever to support new parents in these formative years. While it isn't the end of the baby brain story, new parents can take solace in the fact that becoming a new parent doesn't inherently impair their memory and cognition."
Read the full paper in the journal, Cortex: Baby brain? Evidence for no objective cognitive differences between mothers, fathers and non-parents in the post-partum period. DOI:
https://doi.org/10.1016/j.cortex.2026.04.003
