To date, numerous studies suggest that being put under with anesthesia early in life seems somehow related to future cognitive problems. But whether this association is causal or merely coincidence is unclear.

Researchers do know that the young human brain is exceptionally sensitive. When kids are exposed to certain harmful chemicals in their formative years, that experience can fundamentally alter the brain’s architecture by misdirecting the physical connections between neurons or causing cell deaths. But unraveling whether anesthetics may fuel such long-term damage in humans remains a challenge.

The connection does seem plausible. Anesthetics are powerful modulators of neurotransmission, or communication between neural cells, so the idea that early exposure to these chemicals may alter brain development does not seem far-fetched. Moreover, anesthesia exposure in animals has been linked to long-term learning and memory problems for almost all commonly used anesthetics.