Tom saw the ball take off a split second before he heard the crack of the bat. It was a line drive just a few feet off the ground, and it was coming his way. He stretched out his arm and dove to the right. The next thing he knew, he was lying on the floor beside his bed and had nearly put his fist through the bedroom wall.
With a bemused smile, he lifted his hand and showed me the scrapes on his knuckles. “I tell you, doc, I thought I was playing ball again. It was so real.”
He had once played semiprofessional baseball, and he was still in good shape at 67. Now he and his wife sat in my exam room as he described the intensely vivid dream he’d had two nights before. His wife nodded her head in agreement.
“Sometimes he hits me,” she said.
“Yeah,” her husband agreed. “It’s the oddest thing. I’m asleep when it happens. I don’t even know I’m doing it.”
My antennae went up and I quickly scanned her up and down. I noted a couple of old bruises on her bare arms.
“He’ll thrash in bed at night, sometimes kick, and maybe even take a swing at me,” she added.
I looked from him to her and then back to him. Had he been abusing her? There was no sense of tension, and I caught no furtive glances or avoidance of eye contact with me. They both just looked perplexed. For 20 years I had known them to be devoted to each other. My patient was the last person I would suspect of spousal abuse. And if this really was abuse, why were they here in my office telling me a story about wild dreams? Still, fading bruises on the wife’s forearms might be defensive injuries.
Did they fit the profile? I briefly considered the risk factors for spousal abuse, or what is now called intimate partner violence: a history of substance abuse, recent unemployment, low academic achievement, a history of physical abuse. None were present. The injuries associated with intimate partner violence—located about the face and neck and in areas covered by clothing, such as chest, breasts, and abdomen—to my knowledge had never occurred in this couple. In my gut I didn’t believe this was intimate partner violence, but abuse can occur in even the most unexpected settings, and I couldn’t afford to miss it. If abuse is suspected, I am required to report it. I needed to know more.
They told me that the vivid dreams and bizarre nighttime behavior had been going on for two years. “Last week he was screaming in his sleep,” Tom’s wife offered.
“Screaming?” I asked him.
“Yeah. I dreamed I was in a courtroom and we lost the case and I started screaming at my lawyer.” He shook his head, baffled and even embarrassed by his imagined behavior.
I shook my head too. Something was definitely wrong. I thought about the stages of normal sleep. When we go to bed at night, we cycle through two states. The more distinctive state is REM (rapid eye movement) sleep. Although we are profoundly asleep in this state, a measuring device called an electroencephalogram, or EEG, attached to the scalp will show brain wave activation that paradoxically looks almost like the activity of the brain when a person is awake. Most of our dreaming occurs during this period. It is also the time when we consolidate memory and refresh ourselves psychologically. (Anyone who has ever been sleep-deprived for a couple of days knows how important this is.) But one thing we don’t do while dreaming in REM sleep is move.
A cardinal feature of REM sleep is atonia, which is the complete absence of activity in all voluntary muscles. During a dream, we lie in our beds as if paralyzed, but one group of muscles continues to operate. Our eyeballs move about in bursts of activity, presumably “watching” the adventures unfolding within our slumbering brains. Hence the term rapid eye movement sleep.
In non-REM (NREM) sleep, the other sleep state, an EEG will show the slowed electrical patterns of decreased brain activity. Normally we cycle through NREM and REM sleep several times each night.
However, as Prince Hamlet famously observed, sleep is not always untroubled. There is a group of phenomena known as parasomnias, unpleasant physical activities that can occur when someone is in a twilight state between deep sleep and wakefulness. I wondered if my patient might be suffering from one of these. Walking and talking in one’s sleep are parasomnias familiar to most people. But both of these occur in the lighter, NREM sleep and are not associated with dreaming. In fact, if you awaken sleepwalkers they will be confused and disoriented, demonstrating none of the vivid recall of dreams. In contrast, the frightening dreams that we call nightmares do occur in REM sleep. Though dramatic and often memorable, they are not normally associated with movement. From what he described, it seemed that my patient was neither dreamlessly sleepwalking nor lying motionless, trapped within a nightmare.
The only parasomnia associated with dreaming and movement is the uncommon neurologic condition known as REM sleep behavior disorder (RBD). While deep in REM sleep a patient with this disorder may kick, punch, or fling himself about while acting out his dreams. The dreams of patients with RBD often have aggressive content. Sleep partners may be injured or patients may hurt themselves, as my patient had done while diving for a line drive. Cases have been reported of patients choking their sleep partners in the context of defending themselves while dreaming about being attacked. Like Dr. Jekyll and Mr. Hyde, a patient with RBD may be mild mannered in the daytime (patients with this disorder typically are) but may utter profanities and commit violent, aggressive acts while dreaming. The episodes last several minutes.
To confirm my hunch that RBD was haunting my patient’s nights, I arranged for him to spend a night later that week in a sleep lab. He agreed, and as he lay dreaming, sensors over his muscles—in a test known as a polysomnogram—showed that the normal paralysis of REM sleep was being disrupted. Clearly he had RBD. Whatever violence was occurring in the couple’s bedroom was the result of a neurologic disorder.
The pioneering sleep researcher William Dement once said, “Dreaming permits each and every one of us to be quietly and safely insane every night of our lives.” But in REM sleep behavior disorder, the safety net has been rolled up and dreaming becomes risky. The exact cause of RBD is unknown, although it is often associated with degenerative neurological conditions. Also not known is why it occurs most frequently in older men. Fortunately, the disorder can be treated with a Valium-like medication called clonazepam.
The next day I reviewed the findings of the sleep study with my patient and his wife, explaining to them what was happening when he dreamed at night. I prescribed the medication, and once he started it the dream-associated activities stopped almost immediately. As long as he took his pill each night, he and his wife both slept better. Frankly, I slept better too, knowing that they were indeed the loving couple I had always thought them to be.
H. Lee Kagan is an internist in Los Angeles. Cases described in Vital Signs are real, but names and certain details have been changed.
