Why Can’t I Wink? The Science Behind the Skill

Winking is surprisingly difficult because it demands a level of independent neural control over each eyelid that goes well beyond what ordinary blinking requires. When you blink, both eyelids close together in a coordinated reflex. When you wink, your brain has to selectively shut one eye while actively keeping the other open, and that recruits additional brain regions that blinking does not involve. Roughly two-thirds of people in one study could only wink on one side, which suggests that the neural circuitry for independent eyelid control is not something everyone develops equally.

Blinking and Winking Use the Same Muscle Very Differently

Both actions rely on the orbicularis oculi, the ring-shaped muscle that encircles each eye socket. But that muscle is not a simple on-off switch. Research using electrodes placed at multiple points across the muscle has shown that different segments of the orbicularis oculi activate in distinct patterns depending on what the eyelid is doing. A gentle blink, a forceful squeeze, and a deliberate wink each produce a different map of muscle fiber recruitment.¹ The muscle is wired in segments, and the brain has to activate those segments in precise combinations to get the eyelid motion it wants.

The nerve supply to this muscle adds another layer of complexity. The facial nerve branches in specific ways as it travels across the face, with the zygomatic branch taking an angled path through the cheek to reach the lower eyelid and the inner portion of the upper eyelid.² Individual differences in how these nerve branches are arranged could help explain why some people struggle with fine eyelid control on one side. If the nerve pathway serving one eye’s muscle is slightly less favorable for independent activation, that side becomes the harder one to wink.

Your Brain Recruits Extra Territory for Winking

Brain imaging studies have revealed a clear difference in how much cortical activity blinking and winking generate. When people blink, their frontal eye fields and supplementary eye fields light up on fMRI scans. When they wink, those same regions activate, but so does the posterior parietal cortex, a region involved in spatial awareness and attention. Both the frontal eye fields and the posterior parietal cortex showed significantly greater activity during winking than during blinking.³ In plain terms, winking is not just “half a blink.” It is a more deliberate act that pulls in brain areas associated with voluntary control and spatial processing.

This explains the subjective feeling many people have that winking requires concentration while blinking is effortless. Blinking happens reflexively thousands of times per day, and each blink lasts only about 100 to 150 milliseconds.⁴ Your brain handles it automatically. Winking, by contrast, requires your motor cortex to suppress the natural tendency for both eyes to close together, and then keep one open while closing the other. That suppression is the hard part, and it is where many people hit a wall.

Why One Eye Is Easier to Wink Than the Other

If you can wink at all, you have almost certainly noticed that one eye cooperates much more readily. This is not your imagination. Brain imaging shows strikingly different activation patterns for left versus right winking. Left winking tends to activate areas confined to the left hemisphere, while right winking produces more widespread, bilateral activation across both hemispheres.⁵ The broader activation for right winking suggests it takes more neural effort. This asymmetry appears to be consistent with the everyday observation that most people find left winking easier, and it may explain why left winking is more commonly used for aiming and social signaling.

What is interesting is that this asymmetry does not seem to map neatly onto handedness. In a study of 63 subjects, the split among unilateral winkers between left-only and right-only was roughly even, even though the group was mostly right-handed.⁵ So whatever determines your “winking side” appears to be independent of which hand you write with. The neural pathways for fine eyelid control follow their own logic.

Eye Dominance and the Eye You Cannot Wink

There is a curious link between which eye you struggle to wink and which eye is your dominant one. A study of 56 students in grades four through twelve who could only wink one eye found that their non-winking eye was consistently their dominant eye in sighting tasks.⁶ In other words, the eye your brain favors for looking through a telescope or lining up a shot is the one it refuses to shut independently.

This makes a certain intuitive sense. Your dominant eye is the one your visual system leans on more heavily, so your brain may resist shutting it down. The neural pathways that keep it open and active could be harder to override with a voluntary closure command. If you have ever tried to wink your dominant eye and found that the other eye squeezes shut in sympathy, this resistance is what you are fighting against. Your brain is essentially prioritizing its preferred visual input over your desire to look coy.

Children Learn Independent Eye Closure in Stages

Nobody is born knowing how to wink. The ability to use one eye independently develops over childhood in a predictable sequence, and some people simply never complete the final stage. Research tracking how children learn to look through a tube or telescope laid out four developmental phases. Young children, around age three, hold the tube at the midline of their face and keep both eyes open. By about age five or six, they start placing the tube closer to one eye but still keep both open. Around age seven, they learn to turn their head to help aim with one eye. It is not until roughly age nine and a half, on average, that children learn the adult response: placing the tube over one eye and closing the other.⁷

The key word in that research is “learn.” Closing one eye independently is not purely a matter of having the right muscles. It requires the brain to develop the motor programs for suppressing bilateral closure, and that development takes years. Some adults who struggle to wink may simply have never fully developed this particular motor skill during childhood, and it persisted into adulthood as a gap in their voluntary motor repertoire. The good news is that unlike many developmental windows, this one does not appear to slam shut.

Yes, You Can Train Yourself to Wink

The most encouraging finding for frustrated non-winkers is that the skill can be acquired with practice, even in adulthood. In the same brain imaging study mentioned earlier, 41 subjects who could only wink on one side were given a month to practice winking with their difficult eye. About half of them learned to do it successfully within that time frame.⁵ That is a remarkably high success rate for what feels like such a stubborn inability.

What the brain scans revealed about these newly trained winkers was telling. After learning, the cortical areas they activated were the same regions that natural bilateral winkers used. The brain did not have to recruit novel areas or rewire itself in some dramatic way. Instead, learning strengthened activation in regions that were already involved in winking on the easy side.⁵ The circuitry was there all along; it just needed to be exercised. This is good evidence that the inability to wink both eyes is not a hardwired genetic limitation for most people. It is a motor skill, and like most motor skills, it responds to deliberate practice.

If you want to try, the practical approach is straightforward. Start by manually holding the stubborn eye closed with a finger while opening the other eye. Repeat this many times a day so your brain starts to associate the sensation of one-eye-open, one-eye-closed with the motor command. Over time, reduce the finger assistance. Some people find it helpful to practice in front of a mirror, and others benefit from squinting hard with both eyes and then trying to release just one. Patience matters: the study gave subjects a full month, and only half succeeded in that window, so do not expect overnight results.

When the Problem Is Medical, Not Just Motor

For most people who cannot wink, the issue is simply an undeveloped voluntary motor skill. But in some cases, difficulty with independent eyelid control signals something going on with the nerves themselves.

Facial synkinesis is a condition where moving one set of facial muscles triggers an unwanted involuntary movement in another set. The most widely accepted explanation is that it results from misguided nerve regeneration after the nerve fibers sustaining the facial nerve have been damaged.⁸ When nerve fibers regrow after injury, they sometimes plug into the wrong muscles. This can mean that trying to close one eye also pulls up the corner of your mouth, or that smiling forces one eye shut. The possible mechanisms include misdirected sprouting of regenerating nerve fibers, loss of the insulating myelin sheath around nerves, and scarring within the facial nerve nucleus in the brainstem.⁹

Synkinesis most commonly appears in people recovering from Bell’s palsy or other forms of facial nerve damage, and it can significantly affect quality of life. The involuntary movements impair facial appearance and emotional expression, and they can cause real psychological distress.¹⁰ If your difficulty with winking appeared suddenly after an illness or injury affecting your face, or if it is accompanied by other involuntary facial movements, it is worth mentioning to a doctor. Treatment options include targeted physical therapy and botulinum toxin injections to quiet the misfiring muscles.

Marcus Gunn Jaw-Winking Syndrome

There is also a congenital condition that produces an unusual and involuntary version of winking. Marcus Gunn phenomenon, sometimes called jaw-winking, is a rare form of facial synkinesis present from birth. People with this condition experience an involuntary eyelid elevation when they move their jaw, such as during chewing or opening the mouth wide.¹¹ It looks like a wink triggered by chewing, but the person has no control over it.

The suspected cause involves miswired nerve connections that are present from development. One theory is that a branch of the trigeminal nerve, which controls jaw muscles, has been congenitally misdirected to connect with the nerve fibers that lift the upper eyelid. Another possibility is that certain brainstem neurons that normally regulate eyelid tension fire inappropriately in response to signals from the jaw-control neurons.¹² Either way, the result is a cross-wiring problem that links two motor programs that should be independent. Marcus Gunn phenomenon is present in a small fraction of people born with drooping eyelids, and while it is more a curiosity than a danger, it can be cosmetically bothersome and is sometimes corrected surgically in childhood.

Why Humans Have Such Complicated Eyelid Control at All

It is worth stepping back to ask why our eyelid muscles are wired with such fine-grained, segmental control in the first place. Most mammals blink, but the rich repertoire of independent eyelid movements humans can perform, including winking, squinting one eye in bright light, and producing the subtle half-lid expressions that are central to nonverbal communication, reflects the unusual complexity of primate facial musculature. Comparative studies of facial muscles across primates and other mammals have documented how these muscles have diversified and become more finely subdivided over evolutionary time, particularly in the great apes and in humans.¹³

The segmental control of the orbicularis oculi that makes winking possible is part of this broader trend. Humans use their faces as communication devices to an extraordinary degree, and fine control over the eye region is especially important for conveying emotion, signaling intent, and directing attention. The wink itself is a culturally loaded gesture, carrying meanings from flirtation to conspiracy to reassurance depending on context. The fact that the neural infrastructure supporting it is so demanding, requiring extra cortical recruitment and years of developmental learning, hints that independent eyelid control was not a primary evolutionary target. It is more like a side benefit of having facial muscles subdivided finely enough for the full range of human expression. Winking is something the system can do, but it was not specifically designed to do easily.

Common Misconceptions About Winking Ability

One widespread assumption is that the inability to wink is genetic and permanent, something you are either born with or not. The training data described earlier pushes back on that. Researchers who investigated whether winking laterality was an inherited trait found that among their subjects, left-only, right-only, and bilateral winking were distributed roughly equally regardless of handedness, and the skill could be learned within weeks.⁵ That pattern is not what you would expect from a strongly genetic trait. Winking ability appears to be more like whistling or snapping your fingers: a motor skill that some people pick up incidentally in childhood and others never get around to practicing.

Another misconception is that people who cannot wink have weaker facial muscles. In almost every case, the muscles are perfectly strong. Both eyes close with full force during a hard blink. The deficit is in the brain’s ability to activate one side independently while suppressing the other, not in the muscles themselves. This is a control problem, not a strength problem, and that distinction matters because it means the solution is practice and motor learning, not exercise in the traditional sense.

A third common belief is that struggling to wink on one side means something is wrong with the nerve on that side. For the vast majority of people, it does not. Nerve damage from Bell’s palsy, injury, or surgery produces a constellation of symptoms, including weakness across the entire affected side of the face, drooping, and sometimes the synkinetic movements described above. If the only thing you cannot do is wink your left eye, but you can blink both eyes, raise both eyebrows, and smile symmetrically, your facial nerve is almost certainly fine. You just have an untrained motor program on that side.

Frustrating as it can be, the inability to wink belongs in the same category as not being able to raise one eyebrow or wiggle your ears. These are all voluntary movements that require your brain to isolate muscles that normally fire in pairs, and some people’s motor cortices are better set up for that kind of fine independent control. For those who want to add winking to their skill set, the evidence suggests that a month of daily practice stands a reasonable chance of getting you there.