Fear of the Dark

An intense fear of the dark is common enough to rank in the top five fears for more than half of one undergraduate sample, and those students rated night photographs as less comfortable than the same places in daylight. Nyctophobia is not a separate disorder in DSM-5-TR; it is a specific phobia only when the fear is excessive, persistent, and disruptive enough to meet those criteria.

Nyctophobia is a name for an intense fear of the dark, not a separate DSM-5-TR disorder. A college study found night scenes less comfortable than the same places by day, and clinical criteria decide when that discomfort is a phobia.

An intense fear of the dark is common enough to rank in the top five fears for more than half of one undergraduate sample, and those students rated night photographs as less comfortable than the same places in daylight. Nyctophobia is not a separate disorder in DSM-5-TR; it is a specific phobia only when the fear is excessive, persistent, and disruptive enough to meet those criteria.

Darkness is a thin stimulus. It removes the information the eyes use, and the mind supplies the rest. For many people that is a flicker at the end of a hallway. For some it organizes the evening: which rooms stay lit, which streets are skipped, whether sleep requires a lamp. The clinical question is not whether the dark can feel unsafe. It is whether the fear has crossed into a specific phobia.

What one adult study actually measured

Studies of fear of the dark in adults are scarce. Levos and Zacchilli say so at the start of their 2015 paper, then test it in college students. Participants were 31 men and 91 women at a small private university, 122 people in all. They ranked fears, completed an anxiety survey modified for fear of the dark, and rated comfort with photographs of locations shot both by day and at night (Levos & Zacchilli, 2015).

Over 50% of the participants rated the dark within their top five fears. All seven day/night photo pairs differed: people were more uncomfortable with the night versions. Effect sizes for those pairs ranged from 0.65 to 1.63. Sex differences appeared on all but one pair, with effect sizes from 0.42 to 0.80. The authors treat the childhood pattern — an unrealistic fear of the dark — as something that may turn, in adults, toward a more realistic concern about victimization when you cannot see. They mark that as an interpretation, and they note that future work would need a dedicated fear-of-the-dark inventory and real nighttime walkthroughs, not only photographs.

Read those numbers as a convenience sample of undergraduates, not as the share of adults with nyctophobia. The paper does not diagnose anyone.

Nyctophobia is a name, not a separate diagnosis

DSM-5-TR, as summarized by StatPearls, does not list nyctophobia as its own disorder. Specific phobia is the diagnosis, with specifiers for animals, the natural environment (the examples given are heights, storms, and water), blood-injection-injury, situational fears, and an “other” group that includes loud sounds and costumed characters. Darkness is not named in that example list. A clinician can still consider an intense fear of the dark under specific phobia if the criteria are met (Samra, Torrico, & Abdijadid, 2024).

The National Institute of Mental Health defines specific phobia as an intense, irrational fear of something that poses little or no actual danger. Adults may know the fear is irrational and still get severe anxiety from thinking about the object or situation. Using National Comorbidity Survey Replication interviews fielded from 2001 to 2003, and DSM-IV criteria, NIMH estimates that 9.1% of U.S. adults had specific phobia in the past year and that 12.5% experience it at some time in their lives. Past-year rates were higher for women (12.2%) than for men (5.8%). Of adults with past-year specific phobia, an estimated 21.9% had serious impairment, 30.0% moderate, and 48.1% mild (NIMH, specific phobia). None of those figures is a rate for fear of the dark.

The line between a wary walk to the car and a phobia is the one in Is it a fear or a phobia?: proportion, persistence, avoidance, and whether ordinary life shrinks.

What treatment references say

StatPearls describes cognitive behavioral therapy, generally in the form of exposure, as the main psychological treatment when a specific phobia needs treatment. The Merck Manual calls exposure the most extensively studied psychotherapy for specific phobia. Both describe a graded list, from milder contact to the situation the person most avoids, rather than a single flood of darkness (Barnhill, 2026). Sleep that only works with every light on, or a refusal to enter unlit rooms that cuts into work or care of other people, is a reason to talk with a licensed professional rather than to keep adjusting lamps alone. The educational version of a fear ladder is in the exposure therapy guide.

If fear is affecting daily life, talk with a licensed mental health professional. HighFear is educational and does not diagnose, treat, or provide crisis care. In the United States, call or text 988, or text HOME to 741741. More information is at 988lifeline.org.

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Frequently Asked Questions

Is a fear of the dark a phobia?

An intense fear of the dark is common enough to rank in the top five fears for more than half of one undergraduate sample, and those students rated night photographs as less comfortable than the same places in daylight. Nyctophobia is not a separate disorder in DSM-5-TR; it is a specific phobia only when the fear is excessive, persistent, and disruptive enough to meet those criteria.

What did the college study on fear of the dark find?

Levos and Zacchilli asked 122 undergraduates (31 men and 91 women) at one private university to rank fears and to rate day and night photographs of the same places. Over 50% put the dark in their top five fears. All seven day/night pairs differed, with night photos less comfortable. The sample is not a measure of how many adults have a clinical phobia.

How common is specific phobia, as a category?

The National Institute of Mental Health, using National Comorbidity Survey Replication interviews from 2001 to 2003 and DSM-IV criteria, estimates that 9.1% of U.S. adults had specific phobia in the past year and 12.5% experience it at some point in life. Those figures are for specific phobia as a whole, not for fear of the dark.