When cradling a newborn, parents instinctively support the head and avoid mishaps. But did you know mothers worldwide tend to hold their babies on the left side? Scientists have long observed this, and now experts at St. Petersburg State University have explained it. Their study, published in Nature Ecology & Evolution, shows this position activates the brain's right hemisphere, key for social bonds and communication. Humans aren't unique—horses, kangaroos, great apes, and killer whales do it too.
Past theories suggested left-side holding let babies hear the mother's heartbeat for comfort. That's part of it, but eye contact is crucial. Here, mother and child connect primarily via the left eye, engaging the right hemisphere for attention, memory, reasoning, problem-solving, and deeper communication—strengthening the mother-child bond. Limited eye contact early on may link to behavioral issues or autism spectrum disorders.
Next time you cuddle a baby, keep this in mind!
