Anxiety in Crowded Places: Could Vision Be a Factor?

If a trip to the grocery store, the mall, or a crowded event leaves you uneasy, off-balance, or oddly panicky, the cause may be more mechanical than emotional. Your brain keeps you upright and oriented partly by using what you see. When that visual information is confusing or overwhelming, busy places can feel threatening. At Vision & Learning Center we meet adults who have avoided these places for years. Most never knew their eyes might be part of the picture.

Key takeaways

• Balance draws on the inner ear, body position sense, and the eyes; conflicting visual signals make busy environments harder to process.
• “Visual vertigo” and persistent postural-perceptual dizziness (PPPD) are recognized diagnoses triggered by moving or complex visual scenes.
• Vertical eye misalignment has been linked to visually induced motion sickness, but the link is an association, not proof of cause.
• Prism lenses shift the image so the eyes do not have to strain to line it up. The evidence for prism in vertical heterophoria comes from retrospective, uncontrolled case series from a single practice.

What binocular vision dysfunction is

Your eyes capture two slightly different images that the brain fuses into one. When the eyes are even slightly misaligned, side to side or up and down, the visual system has to work constantly to hold that single image. Doctors call the resulting problems binocular vision dysfunction, or BVD. A vertical misalignment is usually called vertical heterophoria. A scoping review of 56 studies listed the symptoms these problems cause most often. They are headache, blurred vision, double vision, tired eyes, and words that seem to move during near work (García-Muñoz et al., 2014). Our BVD symptoms checklist and our guide to understanding binocular vision dysfunction cover them in depth.

Symptoms alone do not diagnose BVD, though. Among 167 young adults who considered their eyesight normal, visual symptoms were common. But most high scorers on a symptom survey did not have convergence insufficiency, and most who did have it reported no symptoms (Horwood et al., 2014). A checklist is a starting point, not a diagnosis.

Why busy places can feel overwhelming

Visual dependence and “visual vertigo”

Some people lean unusually hard on vision to stay oriented, a trait called visual dependence. One landmark series followed 15 patients whose dizziness was set off by conflicting or disorienting visual surroundings. Most had an inner-ear disorder. The patients who swayed most in response to visual motion included four with strabismic (eye-alignment) symptoms, such as double vision or past eye-muscle surgery (Bronstein, 1995). The author proposed that visual vertigo starts with high visual dependence. Add anything that makes it harder for the brain to sort out conflicting signals, and the stage is set. A supermarket, with its repeating patterns and motion in every direction, is a sensory-conflict machine.

Persistent postural-perceptual dizziness (PPPD)

In 2017 the Bárány Society defined PPPD as dizziness, unsteadiness, or non-spinning vertigo on most days for three months or more. Symptoms get worse with standing upright, with motion, and with “exposure to moving visual stimuli or complex visual patterns” (Staab et al., 2017). The consensus document names passing traffic, large crowds, busy carpeting, and large store displays as classic triggers. PPPD is a functional vestibular disorder, not a structural or psychiatric one. It usually follows an inner-ear illness, another medical problem, or a period of psychological distress. It is also common. PPPD replaced two older diagnoses: phobic postural vertigo and chronic subjective dizziness. At tertiary balance centers that specialized in those two conditions, they made up 15 to 20 percent of everyone arriving with vestibular symptoms (Staab et al., 2017). Anxiety and avoidance often develop as secondary consequences (Popkirov et al., 2018), the pattern many of our patients describe.

Anxiety and balance share wiring

The overlap runs both ways. Researchers coined “space and motion discomfort” for unease provoked by moving crowds, supermarkets, repetitive wall patterns, and heights. One study tested 104 people. Among the anxiety patients, those with high discomfort scores were far more likely to fail balance testing than those with low scores: 52 percent versus 20 percent (Jacob et al., 2009). Feeling anxious in a crowd may reflect a balance system working differently, not just worry.

Where eye alignment fits in

The evidence for a direct line from a small vertical misalignment to feeling sick in a store is suggestive but incomplete. Researchers measured vertical phoria (the eyes’ resting misalignment when fusion is broken) in 43 volunteers who were not eye patients. The larger the phoria, the more easily moving images made a person feel sick. Yet adding prism to increase the misalignment on purpose rarely produced symptoms, and the authors concluded the association may not be causal (Jackson & Bedell, 2012). Our pages on vertical heterophoria and dizziness and vision go deeper.

What the evidence says about prism for vertical heterophoria

So does prism help? Here is what has actually been published.

One retrospective review looked at 43 patients with lasting post-concussion symptoms. After individualized prism lenses, their self-reported symptom burden fell by 71.8 percent (Doble et al., 2010). A second retrospective series from the same group followed 38 patients. It reported 19 to 61 percent reductions on headache, dizziness, and anxiety measures (Rosner et al., 2016). The same practice also validated its Binocular Vision Dysfunction Questionnaire, using 126 of its own patients (Feinberg et al., 2021).

Every one of these studies comes from a single private practice. None had a control group or a placebo. None were blinded. No randomized trial of prism for vertical heterophoria has been published.

Here is our clinical perspective at Vision & Learning Center. Carefully measured prism can be a reasonable option for some adults, when a real vertical misalignment and the symptoms line up. Patients also deserve to hear the state of the evidence before they buy glasses.

What helps

Get the right evaluations. A comprehensive binocular vision evaluation measures eye alignment at distance and near, focusing, eye teaming, and eye movements, not just 20/20 acuity. If dizziness is present most days and has lasted months, ask your doctor about a vestibular evaluation too. The two problems often occur together, and they are treated differently. Our adult BVD page explains what to expect.

Retrain your tolerance for visual motion. Vestibular physical therapists treat visual vertigo with graded exposure to moving scenes. One trial enrolled 40 patients whose chronic dizziness had not improved with standard exercises. Adding visual-motion “simulator” exposure produced a significant improvement in visual vertigo scores, about 54 percent, that the exercises alone did not (Pavlou et al., 2004). The video below, made by a vestibular physical therapist, is an optokinetic exercise (a moving-pattern video that trains tolerance for visual motion) filmed to look like a busy grocery store. Check with your provider first, and keep sessions short. These exercises should be mildly uncomfortable, not overwhelming.

Busy Grocery Store: Optokinetic Training (3:30), Gabrielle Pierce, DPT

Treat PPPD as PPPD. The recognized treatments are vestibular rehabilitation, cognitive-behavioral therapy, and serotonergic medication (antidepressants of the SSRI or SNRI type, used here for the dizziness rather than for mood). They are often combined (Popkirov et al., 2018).

Address the vision piece. Updating a glasses prescription, treating eye-teaming and focusing problems, and prescribing prism where it fits the findings can all lighten the visual load your brain carries into a busy room. The best-supported use of vision therapy is office-based therapy for symptomatic convergence insufficiency in children; adult evidence is less clear (Scheiman et al., 2020).

Use practical strategies meanwhile. Shop at quieter hours, fix your gaze on a stable object when an aisle starts to swim, step outside for a minute when overloaded, and keep moving through mild discomfort rather than freezing.

Bringing it together

Anxiety in visually busy places is real, and there is real biology behind it. It usually has more than one cause. Vision is one piece that is easy to overlook and simple to measure. If this sounds like you, book a comprehensive vision evaluation with us, or Schedule an evaluation online today.