Yes, sustaining multiple concussions over time, even if individually they might seem minor, can indeed have a cumulative effect on the brain. This is sometimes known as "second impact syndrome," particularly when a second concussion occurs before the brain has fully healed from the first. Over time, repeated concussions can lead to prolonged recovery times and increase the risk of developing chronic traumatic encephalopathy (CTE), a degenerative brain disease associated with repeated head traumas. It underscores the importance of full recovery before returning to activities that risk additional head injury.