You know why I’m certain that the singularity predictions are complete bunk? Because we know so little about the brain that we’re still not altogether sure what causes “brain freeze,” those hideous headaches you get from that first, always-too-fast sip of a Slurpee.
Until recently, there was some speculation that it had to do with the cooling/warming of sinus blood vessels. Not so, says some new research:
By bringing on brain freeze in the lab in volunteers and studying blood flow in their brains, the researchers show that the sudden headache seems to be triggered by an abrupt increase in blood flow in the anterior cerebral artery and disappears when this artery constricts. The findings could eventually lead to new treatments for a variety of different headache types.
In this study, Serrador and his colleague recruited 13 healthy adults. The researchers monitored the volunteers’ blood flow in several brain arteries using transcranial Doppler while they first sipped ice water with the straw pressed against their upper palate—ideal conditions for bringing on brain freeze—and then while sipping the same amount of water at room temperature. The volunteers raised their hand once they felt the pain of a brain freeze, then raised it again once the pain dissipated. Findings showed that one particular artery, called the anterior cerebral artery, dilated rapidly and flooded the brain with blood in conjunction to when the volunteers felt pain. Soon after this dilation occurred, the same vessel constricted as the volunteers’ pain receded.
Changing the Course of HeadachesSerrador and his colleagues speculate that the dilation, then quick constriction, may be a type of self-defense for the brain. “The brain is one of the relatively important organs in the body, and it needs to be working all the time,” he explains. “It’s fairly sensitive to temperature, so vasodilation might be moving warm blood inside tissue to make sure the brain stays warm.” But because the skull is a closed structure, Serrador adds, the sudden influx of blood could raise pressure and induce pain. The following vasoconstriction may be a way to bring pressure down in the brain before it reaches dangerous levels.
Lest you think this is some kind of pointless exercise, the real purpose of the study was to better understand the causes of migraines and other persistent headaches. The idea is to use “brain freeze,” which can be induced safely and without the use of drugs, to understand more serious medical problems.