To be alive is to feel fucking terrible, if not all then at least some of the time. Headaches, nausea, mysterious aches and pains—all conspire to make our short time on Earth something less than a nonstop thrill-ride. Worse than the routine ailments are the ones you can’t even name: sudden strobes of unwellness you need a doctor (not to mention health insurance) just to get some handle on. The feeling, for example, that you’re falling, when you’re demonstrably doing nothing of the kind. Where does that sensation come from, and what can you do about it? For this week’s Giz Asks, we reached out to a number of experts to find out.
Helen S. Cohen
Professor, Otolaryngology—Head and Neck Surgery, Baylor College of Medicine
The illusory sensation of movement when you know that you are really not moving is called vertigo. It could be a sensation of falling, or whirling, or gently rocking. A related sensation, when you know that you are not moving, but the world around you looks like it is moving, is called oscillopsia. People usually have vertigo or oscillopsia when they have a disorder of the vestibular system. That is the sensory system with receptors hidden deep inside the inner ear. The receptors in the vestibular labyrinth, made of tiny fluid-filled tubes and sacs, are like a set of accelerometers. They provide information to tell your brain that your head is moving and about the direction, speed, and distance of the movement. Some disease processes that affect the vestibular system can cause vertigo or oscillopsia.
Also, under some unusual circumstances, people with normal vestibular systems can temporarily experience vertigo. For example, as a child, did you ever twirl around, stop, and then feel as though you were still moving? That’s vertigo. Did you ever go for a boat ride on a day with a lot of waves, and afterward you felt briefly that you were still moving? That’s vertigo, too. In both of those situations the brain centers that receive information from the vestibular labyrinth get over-stimulated, store the information, and take some time to dump out their storage of information about head velocity. Did you ever go to a movie, sit in the dark, and watch the entire scene on the big movie screen moving, such as a car chase, and you felt that you were moving? That’s vertigo elicited by moving visual images. The centers in the brain that receive information from the vestibular system also get information from your eyes, so your brain can turn on your vestibular system with moving visual images, even though you are sitting still.
Erik S. Viirre
Neurotologist and Professor of Neurosciences at UC San Diego Health
The most common condition that causes a feeling of falling is called benign paroxysmal positional vertigo, or BPPV, and it’s super-common. Tens of millions of people experience it every year—I’ve seen thousands of patients with it. It’s a malfunction of the inner ear balance sensors, which we usually use to maintain balance.
The inner ear balance sensors have two parts. One, the [?], is what is used to measure linear motion like gravity. It has a big lump of a crystal in each inner ear, which is used as a tipping sensor: the brain uses it to measure if your head is tipping. Sometimes, out of the blue, bits of the crystal will come loose and end up in the inner ear turning sensor—known as the semicircular canals—which detect the rotation of your head. In this condition, the loose crystal from the linear accelerometer, the [?], ends up in the rotational accelerator, and so when you tip your head to change your position, the crystal floats around in there and disrupts the fluid dynamics of the rotational accelerator and you get a terrible spinning attack. Usually the loose crystals dissolve and it goes away.
The best part is that it’s something I can fix in about two minutes. It turns out there’s a procedure called the Epley maneuver, where a series of turns of the head will clear the loose crystals out of the inner ear turning sensor and fix the problem. I’ve had people who’ve dealt with this problem for 25 or 30 years, where every time they tip their head the wrong way they get dizzy, and I lay them back and roll them on their side and fix them in a minute or two.
Alaina Bassett
Assistant Professor of Clinical Otolaryngology Director of the Balance Center at the University of Southern California
The vestibular system is located within the inner ear and is responsible for determining the position of our head in respect to gravity. The vestibular sensory organs detect angular motion and linear displacement of the head as we move through space. With five vestibular organs on each side of our head we are sensitive to movement in the roll, pitch, and yaw planes. The vestibular system does not work alone to coordinate our body as we move through our environment. By integrating with the visual and somatosensory systems, we can maintain stable vision and coordinate our limbs to safely move through our day, avoiding falls. A fall or the perception of a fall can be closely related to a dysfunction within the vestibular organs. If we are uncertain of the position of our head and space due to a change in the sensitivity of the vestibular system, we depend more readily on our visual and somatosensory systems to keep us safe. A fall can be defined as unintentionally coming to rest at a lower level without external force (ex. being pushed to the ground). Typically, we experience falls when we are in motion.
Conversely, at times we can perceive that we are falling or that we are in motion even when we are still. Specific changes within the vestibular system produce a sudden “pulling or dropping” sensation that can result in an actual fall if not seated. It is possible that other systems within our bodies can act on the vestibular system to influence our perception of motion. Changes in cardiovascular function, increased stress or anxiety, and/or neurologic conditions can result in the feeling that we are falling or uncertain of where our head is in space. If the sensation of falling for no reason occurs frequently or is associated with specific activities, consider consultation with your primary care physician for further evaluation.
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