Three years ago I wrote an essay for Well about the chronic dizziness that had devastated my life. In response, I received thousands of letters, calls, tweets, emails and messages from Times readers who were grateful to see a version of their own story made public.
Their symptoms varied. While some experienced a constant disequilibrium and brain fog that were similar to mine, others had become accustomed to a pattern of short periods of relative health alternating with longer periods of vertigo.
Most of them, like me, felt that family and friends often didn’t understand how dizziness could be so debilitating. They told me that the combination of the loneliness and feelings of uselessness that come from an inability to work or spend time with family led to despair and depression. And, most commonly, they felt that the medical system made them feel responsible for their own suffering.
“Doctors began to suggest that anxiety or depression were the cause of my symptoms,” a young woman from Connecticut wrote. “I eventually gave up on the quest for answers, as their attitudes added stress to an already stressful reality.”
“Have been to so many doctors that keep saying, ‘It’s all in your head. There’s nothing wrong with you,’” wrote an older woman from Ohio.
“Mostly been told there is nothing they can find,” wrote a middle-aged woman from Illinois. Her doctor told her it was probably just depression and anxiety.
Dizziness is among the most common reasons people visit their doctor in the United States. When patients first experience prolonged dizziness, they may go to an emergency room or to see their primary care physician. That’s what I did. And I heard what most patients hear: “People get dizzy for all sorts of reasons, and it should resolve itself soon.”
It’s true that dizziness often is a temporary symptom. The most common causes of dizziness are benign paroxysmal positional vertigo (caused by displaced pieces of small bone-like calcium in the inner ear), and vestibular neuritis (dizziness attributed to a viral infection or tiny stroke of the vestibular nerve), both of which typically last only weeks or months.
But approximately 20 percent of cases remain chronic, escape explanation, or both.
For me, as for so many thousands of others, the dizziness did not resolve itself, so I saw an otolaryngologist, a specialist in ear, nose and throat disorders. After an examination, the doctor said my inner ears looked good to him and sent me on my way.
My vision had become blurry, so next I made an appointment with an ophthalmologist, who said my eyes were perfect. “It’s probably just stress and will go back to normal when things calm down,” she added.
It took a few months to get an appointment with a neurologist, who ordered a CT scan and an M.R.I. Both tests were clear. “Congrats!” he said. “No tumor. No Parkinson’s. No M.S. You’re good to go.”
But I couldn’t work or interact with my family, and most nights ended with me in tears. I was not good to go.
One of the problems for patients with dizziness is that doctors tend to be siloed into their own specialties by body part — eye, ear, brain. But dizziness is a problem with the vestibular system, which is the sensory system that collects data from the eyes, inner ear and muscles to help us keep our balance and posture. For many dizzy patients, each individual body part can test as healthy, but when they’re all connected, the system does not properly function.
And even the relatively small number of experts who do have appropriate training are often motivated by the insurance system to conduct exams and tests, rather than spending time talking to patients. And if the tests don’t reveal the source of the problem, they tell us it must by psychological, essentially blaming us for our own illness.
Because my wife works a corporate job and we live in New York City, I am lucky. I have great health insurance, proximity to local vestibular specialists, and access to some of the best university hospitals in the world. I was first diagnosed with vestibular migraine, and have since received a second diagnosis of persistent postural-perceptual dizziness, or PPPD. It’s an increasingly common diagnosis that describes chronic dizziness initially caused by one factor, like a virus or a fall, that has since affected the system as a whole. But even among experts there is disagreement about whether PPPD is a distinct condition or just an umbrella term.
My advice for people who suffer from dizziness is to be explicit with family, friends and co-workers about exactly what your symptoms are and how they affect your life. Vestibular disorders are invisible, which contributes to the loneliness sufferers feel.
I’ve learned other lessons about the specific steps that most dizzy patients should take.
If at all possible, make an appointment with a specialist in dizziness. There are excellent dizziness and balance centers across the country, including those at New York University, UPMC, the Mayo Clinic and Johns Hopkins. The Vestibular Disorders Association is a valuable resource for information and to find providers in your area. It is also important to continue to seek second and third opinions if you feel as though a particular specialist isn’t right for you.
Acknowledge the psychological distress these disorders cause. Do your best to find and meet regularly with a psychotherapist who has experience working with patients who suffer from chronic medical conditions. Find a support group on Facebook. I have made beneficial connections in online forums where thousands of people trade advice, encouragement and consolation.
The diagnosis of PPPD was useful for me in that it came with a new set of medications — a combination of Xanax, which makes the nerves in the brain less sensitive to stimulation; Zoloft, which regulates the brain chemical serotonin; and verapamil, a blood pressure drug. This drug regimen has given me a few hours of clarity each day. I can teach again and enjoy time with my family.
I am also writing again. In my new novel, which comes out in March, the protagonist suffers from the same symptoms that I do: the brain-fog, dizziness, vision loss and discombobulation along with the existential anxiety that these symptoms will last forever. Writing the novel allowed me to process my own experience and better think through the experiences of my loved ones who have supported me throughout the ordeal. The hope I now feel about my future, even one that includes dizziness, is captured in a scene where the main character’s wife asks her husband if he feels better.
“Not really,” he says. “But I’ve been doing more. I’ve been better at imagining the life I want to live.”
Jewel wing damselflies live up to their names: They dart through the filtered sunlight of ferny stream beds and forests like wands made of brilliantly colored gems.
“They fly around like little helicopters until they see prey,” usually smaller flying insects, said Paloma Gonzalez-Bellido, a biologist at the University of Minnesota. Then they lunge at their meals in a burst of speed.
A male jewel wing damselfly hovers over a female in slow motion.CreditCredit…By Michael Hutchinson
You might mistake jewel wings for their colorful cousins, dragonflies. New research shows that these two predators share something more profound than their appearance, however. In a paper published this month in Current Biology, Dr. Gonzalez-Bellido and colleagues reveal that the neural systems behind jewel wings’ vision are shared with dragonflies, with whom they have a common ancestor that lived before the dinosaurs. But over the eons, this brain wiring has adapted itself in different ways in each creature, enabling radically different hunting strategies.
For flying creatures, instantaneous, highly accurate vision is crucial to survival. Recent research showed that birds of prey that fly faster also see changes in their field of vision more quickly, demonstrating the link between speed on the wing and speed in the brain.
But the group of insects that includes jewel wings and dragonflies took to the air long before birds were even on the evolutionary horizon, and their vision is swifter than any vertebrate’s studied thus far, said Dr. Gonzalez-Bellido. Researchers looking to understand how their vision, flight and hunting abilities are connected are thus particularly interested in the neurons that send visual information to the wings.
Jewel wings’ behavior involves attacking what’s directly in front of them, the team found.
A jewel wing damselfly closes in on a bead on a string held by a researcher.CreditCredit…By Supple Et Al. 2020
But recordings made in the lab by Dr. Gonzalez-Bellido and her colleagues confirmed that dragonflies rise up in a straight line to seize unsuspecting insects from below, almost like their prey had stepped on a land mine.
A dragonfly hovers up to capture a bead in a lab.CreditCredit…By Supple Et Al. 2020
The difference in hunting behavior may be linked to the placement of the insects’ eyes. Jewel wings’ eyes are on either side of the head, facing forward. The eyes of these dragonflies — the species Sympetrum vulgatum, also known as the vagrant darter — encase the top of the insect’s head in an iridescent dome, with a thin line running down the middle the only visible reminder that they may have once been separate.
“Both eyes work together as a continuous panorama,” said Dr. Gonzalez-Bellido of such dragonflies.
The visual neurons that guide the dragonfly’s wing muscles operate almost as if the creature had a single eye with a cross hair running vertically, prior research has found.
To look closer at the neurons linking vision and flight, the researchers equipped jewel wings with sensors and showed them a video of a moving dot, comparing it with earlier dragonfly research. When a neuron fired, a popping sound filled the researchers’ ears, allowing them to tell exactly which movements — left, right, up, down or some combination — each neuron responded to. Jewel wings best see what’s right in front of them, they found, while dragonflies’ clearest vision is just above them.
Traces of neural activity in a damselfly.CreditCredit…By Supple Et Al. 2020
The team was intrigued to find that while jewel wing neurons didn’t always respond like those in dragonflies, the number of neurons and organization were similar. That suggests that the system that conveys this information from the eyes to the wing muscles did not evolve recently, but has roots that are millions of years older than the oldest dinosaurs. And that ancient common ancestor likely had already developed remarkable speed in both vision and flight. Then, in the intervening eons, the system has evolved to suit individual insect species.
The most distinctive difference appeared when the researchers blocked the view of either of a jewel wing’s eyes using a black eye patch. If either eye was covered, certain neurons fell silent. These neurons were getting messages from both eyes.
That suggests that jewel wings are summing up information from both eyes as they zip around, something dragonflies do not do. There isn’t evidence yet that they can generate 3-D vision and depth perception from their two separate eyes, the way humans (and cuttlefish) do. But it’s possible that having two slightly different visions of the world streaming in at once gives jewel wings a more nuanced view.
Dragonflies hunt in the open, in the bright sunlight, said Dr. Gonzalez-Bellido, where pinpoint accuracy is key. Jewel wings hunt in the mixed shadows and sunbeams of forest streams, where using vision from two separate eyes to avoid obstacles may be more important.
This shared neural system may be more than 250 million years old, but it is also flexible enough to transform itself to meet the needs of a variety of creatures in different eras and environments, the findings suggest.
One potential explanation for this ability is that alone among flying animals, insects’ wings did not evolve from pre-existing limbs, the way those of birds and bats did, said Dr. Gonzalez-Bellido.
“Perhaps being free from having to retrofit a previous system for flying purposes is what allowed the rapid evolution of such an impressive flight controller,” she said.
The cuttlefish hovers in the aquarium, its fins rippling and large, limpid eyes glistening. When a scientist drops a shrimp in, this cousin of the squid and octopus pauses, aims and shoots its tentacles around the prize.
There’s just one unusual detail: The diminutive cephalopod is wearing snazzy 3-D glasses.
Putting 3-D glasses on a cuttlefish is not the simplest task ever performed in the service of science.
“Some individuals will not wear them no matter how much I try,” said Trevor Wardill, a sensory neuroscientist at the University of Minnesota, who with other colleagues managed to gently lift the cephalopods from an aquarium, dab them between the eyes with a bit of glue and some Velcro and fit the creatures with blue-and-red specs.
The whimsical eyewear was part of an attempt to tell whether cuttlefish see in 3-D, using the distance between their two eyes to generate depth perception like humans do. It was inspired by research in which praying mantises in 3-D glasses helped answer a similar question. The team’s results, published Wednesday in the journal Science Advances, suggest that, contrary to what scientists believed in the past, cuttlefish really can see in three dimensions.
Octopuses and squid, despite being savvy hunters, don’t seem to have 3-D vision like ours. Previous work, more than 50 years ago, had found that one-eyed cuttlefish could still catch prey, suggesting they might be similar. But cuttlefish eyes often focus in concert when they’re hunting, and there is significant overlap in what each eye sees, a promising combination for generating 3-D vision.
Dr. Wardill, Rachael Feord, a graduate student at the University of Cambridge, and the team decided to give the glasses a try during visits to the Marine Biological Lab in Woods Hole, Mass. The logic went like this: With each eye covered by a different colored lens, two different-colored versions of a scene, just slightly offset from each other, should pop out into a three-dimensional image. By playing a video on the tank wall of a scuttling pair of shrimp silhouettes, each a different color and separated from each other by varying amounts, the researchers could make a shrimp seem closer to the cuttlefish or farther away. If, that is, the cuttlefish experienced 3-D vision like ours.
To test this hypothesis, the team let the cuttlefish get hungry, then placed them in the tank with the video projected on one wall. The first cuttlefish spied the “shrimp,” and very clearly put itself into reverse, backing up a bit before shooting its tentacles at the mirage.
The cuttlefish backs up before firing its tentacles at a projected shrimp.CreditCredit…By Feord Et Al
“I was ecstatic,” said Dr. Wardill. “We were sort of jumping up and down.” (The cuttlefish was immediately given a real shrimp as a reward.)
That motion of backing up was telling because cuttlefish spring their tentacles at their prey from a specific distance. They rely on suckers at the tips of the tentacles to grip and pull in their meal before biting it. If they are too close or too far, the tentacle tips won’t make contact. The researchers also projected the shrimp image to appear at a distance that made the cuttlefish move forward.
The cuttlefish creeps forward as it spots the projected shrimp.CreditCredit…By Feord Et Al
If cuttlefish were so obviously using 3-D vision to gauge the distance to their prey, why could they still hunt with a single eye, as earlier work had shown? Rather than blinding the animals, the researchers played a video of a single shrimp silhouette, its color chosen so that it would be invisible to one bespectacled eye. While cuttlefish would still launch their tentacles at this shrimp, they paused longer before doing so, suggesting they were not exactly sure if they were at the right distance. Perhaps cuttlefish without depth perception still succeed enough for it not to seem significant to earlier researchers.
Still, if the cuttlefish now joins the praying mantis as one of the few invertebrates known to see in 3-D in this way, the scientists have a long list of questions about how exactly they are doing it. Already, the study suggests that there is something peculiar about the way they transform visual information into depth perception. For instance, it does not bother them if one of the two overlapping images is much brighter than the other, something that humans don’t handle well. They also don’t always line their eyes up in precisely the same direction. Sometimes one of their eyes wanders, in a way that in humans would impair depth perception.
“Their brain layout is very different,” said Dr. Wardill. They likely have evolved ways, in their small, shimmering heads, of generating perceptions that are very different from ours — even if they are capable of wearing 3-D glasses.