The Hidden Epidemic of Brain Injuries From Domestic Violence
The headaches returned during this break, but they were less frequent and easier to bear. Forgetfulness was still worrisome, but she knew she had access to help. The calmness of her new life, with days spent in a dimly lit, quiet apartment, smoothed over her symptoms. But she also knew that they could flare up when stressed and overexcited. In one such case, last June, her child had a severe fever and Becky rushed her to the emergency room. The monitors played out shapes, questions, and screeching beeps as the baby cried on the bed. The lights above were bold fluorescent, the worst for a man with a traumatic brain injury. In the emergency room, Becky felt pressure on her temples and forgot a few simple words. “I need to know my…” She was silent for a few seconds. “Choice”.
Almost all we know about concussions and neurodegenerative diseases from studying the male brain. But some of the studies we have, mostly on the brains of athletes, show that women may be more vulnerable to concussions than men. Concussions jar the gelatinous mass of brain neurons, disrupting circuits that affect mood, function, thinking, and more. Men tend to have more muscular necks that better absorb head acceleration. There are also anatomical differences between male and female axons. Female axons—nerve fibers that unfold between neurons to form communication networks—have a more compact structure that can be sheared more easily during injury. Successive shocks can tear them apart, releasing tau-protein tangles into the brain. But the differences are more than mechanical.
When Ramesh Raghupati, professor of neuroscience and anatomy at the Drexel University College of Medicine, began studying concussions in female rats, he immediately noticed differences from concussions in males. The cellular changes looked similar, but functionally the rats experienced different outcomes, with females experiencing more anxiety and depression. “It has more to do with the circuitry and neurochemistry of the female brain than the male,” he says. “You can’t discount the role of sex hormones.”
In a 2014 study, researchers found that in women of childbearing age, symptoms after a concussion were worse than in postmenopausal women or women taking hormonal contraceptives, especially when the concussion occurred during the luteal phase of the menstrual cycle (after ovulation, before the onset of menstruation). Progesterone levels are high at this time, and one theory is that a disruption in progesterone, possibly caused by damage to the pituitary gland, could have a particularly strong effect on neurons. In other words, the presence of a menstrual cycle in the victim at the moment of impact can significantly affect the outcome of a traumatic brain injury.
A study published last year analyzed female athletes immediately after a concussion. The researchers measured progesterone levels and noted menstrual phases at the time of the injury. Their results were consistent with an association between impaired progesterone production and poorer outcomes, although more data is needed to understand why. (It is estimated that between 31 and 50 percent of transgender people experience intimate partner violence, with a higher rate in transgender women, but no study has analyzed the impact of traumatic brain injury on this group.)
“So much money goes into investigating concussions in sports that these protocols and documents form the picture of concussions in general,” says Steven Kasper, a neuroscience historian at Clarkson University. “There is no money to be made from studying intimate partner violence.” When it comes to chronic neurodegenerative diseases like CTE, even less is known about what women can face after decades of abuse. A slight acceleration or concussion that does not register as a concussion can, if repeated often enough, cause a dementia-like cascade that continues for years after the injury has ceased and is only detectable on post-mortem examination.
At the VA-BU-CLF Brain Bank in Boston, the world’s first CTE-focused brain repository, Ann McKee, director, collected about 1,250 samples. Her discoveries helped change the way football is played and helped redirect hundreds of millions of dollars in victim compensation by getting into the public consciousness about the neurological dangers of contact sports. But 14 years after the bank was founded, almost all of its representatives are still men. The female brain, McKee says, is hard to find, especially in women like Becky. “When you have a situation of interpersonal violence, you must get permission from the next of kin to donate a brain,” she says. Domestic violence carries with it a stigma that can be difficult for families to deal with, and if the perpetrator is the next of kin, there is little chance.