concussion or traumatic brain injury (TBI), and trigeminal
autonomic cephalalgias (including hemicrania continua
and SUNCT) can also cause photophobia. the brain is different than the part that transmits vision. In
fact, a person can be completely blind and still be sensitive
to light.
What is Photophobia? What’s the Science of Photophobia?
Do lights seem too bright to you? Does light make your
head pain even worse when you have a headache or
are in a migraine attack? Do your eyes ever hurt or feel
uncomfortable due to light? Do you have an aversion to
light whether you have pain or not? If you answered “yes” to
any of those questions, you most likely have photophobia.
The word, photophobia is derived from two Greek words:
photo- “light” and phobia “fear or dread of ”—hence, “fear
of light.” However, in medical terms, it is not a morbid fear
or phobia, but rather a symptom, common in migraine, as
well as ophthalmic and other neurological disorders. The
patient with photophobia experiences discomfort or pain
in the eyes due to exposure to light (sunlight, fluorescent
lights, TV or computer screens, or the glare from snow). Photophobia has been recorded in medical writings since
the 1930s, but has not been well understood scientifically
until recent breakthrough discoveries. A team lead by
researchers at Harvard Medical School published a study
in 2010 that found a pathway from the eye to areas of the
brain that are active during a migraine attack. Light can
worsen pain during an attack by activating nerve cells in
these areas of the brain.
Researchers also found a special kind of cell in the eye
–intrinsically-photosensitive retinal ganglion cells. These
cells are distinct from the rods and cones in the eye that
enable us to see. The cells are more sensitive to some
wavelengths of light than others, with particular sensitivity
to blue-green light.
Does the Kind of Light Matter?
The brighter the light, the more discomfort, pain, or
aversion you probably feel. The wavelength or color of light
also plays a role. Blue-green light causes more photophobia
than other colors. Between computer and device screens,
fluorescent and LED light bulbs, and even sunlight, our
lives are awash with this light. Which Headache Disorders Are Associated with
Photophobia?
What Causes Photophobia?
Photophobia is a neurological issue that involves
communication between receptors in the eye and the
brain. The part of the eye that transmits photophobia to
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HeadW ise ®
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Volume 6, Issue 3 • 2017
Migraine
Photophobia is so common in migraine that it is one of
the symptoms that health care practitioners rely on when
making a diagnosis. Between 80 percent and 90 percent
of migraineurs will experience photophobia during
migraine attacks and even can find low levels of light to
be glaring or painful. Between attacks, many people with
migraine are more sensitive to light than those without
migraine.