A University of Queensland study has found women who've just had a baby are much more likely to see faces in everyday objects than other women.

Dr. Jessica Taubert from UQ's School of Psychology led research to determine if face pareidolia—perceiving a facial structure on an otherwise lifeless object—was any more common in new mothers, compared to other women.

"We found postpartum women rated objects with illusory faces as more 'face-like' than expectant women and those not pregnant," Dr. Taubert said. "We believe it may be because of elevated levels of oxytocin in the body after giving birth.

"Oxytocin is known for reducing stress, enhancing mood and promoting maternal behaviors like lactation, so it could contribute to a heightened sensitivity in perceiving faces in objects."

Dr. Taubert said the study was sparked by reaction to a previous research paper into face pareidolia, published in 2022.

"Our team found illusory faces in everyday objects were more likely to be perceived as male than female," she said. "We were subsequently contacted by women who reported that they saw faces in objects more often after giving birth, so we conducted an experiment to examine this theory."

The latest study involved 379 women—79 who'd given birth within the past 12 months, 84 expectant mothers and 216 women who were not pregnant. The participants were asked to rate their ability to perceive faces in a diverse set of images including images of real faces, images of illusory faces in everyday objects and objects without facial features.

"We found postpartum women were more susceptible to face pareidolia," Dr. Taubert said. "We know our brains have heightened sensitivity to anything resembling a face-like structure, and this plays a crucial role in detecting the presence of human faces in our surroundings. Until now weren't aware that our sensitivity to face pareidolia fluctuated throughout different stages of life."

Dr. Taubert says the findings indicate for the first time that hormone levels may have an impact on the basic visual processes responsible for our ability to detect and prioritize faces.

"The research also suggests that our responses to socially-relevant stimuli are heightened during early parenthood," she said. "This opens new lines of investigation because we know very little about how the brain adapts to the unique challenges associated with caring for a newborn."

The findings are published in the journal Biology Letters.