Fear of Spiders

What counts as arachnophobia and what does not

The description of how the fear behaves is unattributed from beginning to end. People are said to feel uneasy anywhere they suspect spiders might be, or that shows webbing, and to stay clear of the area after seeing one until the panic attack passes. The responses listed are:

• screaming, crying and emotional outbursts
• laboured breathing and sweating
• a raised heart rate

In the severe cases the trigger needs no animal in it at all: a photograph, a toy or a lifelike drawing is enough.

What is missing is the threshold. No criteria appear: nothing on how long the fear has to last, or on what it has to cost a person, before a dislike of spiders becomes a diagnosis. That gap matters more than any symptom on the list, because the threshold is the only thing separating the phobia from a preference that enormous numbers of people hold comfortably.

The neighbouring words are worth keeping straight. Spiders are arachnids, so scorpions and ticks sit inside arachnophobia by the definition given, while bees and ants sit outside it under apiphobia and myrmecophobia, and the insects generally under entomophobia.

Why arachnophobia has no coiner and no first date

The name joins the Greek arachne to the Greek phobia, and that is the entire history on offer. No coiner, no first attestation, no date, and no account of the point at which a descriptive phrase turned into a clinical one.

Where the arachnophobia prevalence figure comes from

Arachnophobia affects between 3.5 and 6.1 per cent of the global population. Wikipedia states that flatly and puts no survey, no year, no country and no sample beside it, which is a particular problem for a number claiming global reach, since a world estimate is an aggregation of national ones.

The same passage reports the fear as strongly tied to gender, age, education and how prone a person is to disgust, and says most studies find women more likely to develop it. Which studies is not stated. Nor how many, nor when.

Why eating spiders argues against an inherited fear

In parts of Papua New Guinea and Cambodia, spiders are eaten as traditional food. That is offered as evidence against an inherited fear, on the reasoning that a species-wide instinct ought not to be overridden by a recipe, and it is the sharpest observation in the article.

The inherited account runs like this. Venomous spiders in ancestral environments favoured either a ready-made fear or a strong disposition to acquire one fast. Spiders are far too small to qualify as threats by the usual measure in the animal kingdom, size, but they carry medically significant venom and their setae irritate skin. Anyone who kept their surroundings clear of them was bitten less often, and a slightly lower bite rate is the whole of the advantage being claimed.

Two objections sit beside it:

• there is no evidence of enough dangerous spider species living in Africa during the Pleistocene for such a fear to have evolved there
• a fear out of all proportion to the real ranking of dangers would have carried costs of its own

The strongest evidence for the inherited side is a conditioning result. Arne Öhman, writing in The Handbook of the Emotions in 1993, paired an unconditioned stimulus with images of snakes and spiders on one side and with mushrooms, flowers, drawn polyhedra, firearms and electrical outlets on the other. Snakes and spiders needed a single pairing before a conditioned response appeared, and it then proved permanent. Everything else took repeated pairings and faded once the conditioning stopped, firearms and electrical outlets included: the objects that can actually kill a modern person behaved like the mushrooms.

The competing account holds that the danger was overrated all along, that an inherited phobia would restrict a person more than it ever protected them, and that the fear runs commonest in European societies. No figures are given for that last claim. Press coverage is offered as a mechanism, on the grounds that it often gets the facts about spiders wrong and reaches for sensational language. Nobody has measured whether it does.

Why Nesse says too few people fear spiders

Randolph M. Nesse takes the conditioning result somewhere unusual. A conditioned fear of an evolutionarily novel danger such as an electrical outlet is possible, he argues, but slow, because the cue has no prewired route into the fear system. His example is driving instruction, which leans hard on speeding and drunk driving without producing reliable protection: close to a quarter of deaths among Americans aged 15 to 24 in 2014 happened in traffic collisions.

Nesse, the psychiatrist Isaac Marks and the evolutionary biologist George C. Williams push it further. People whose responses to the fears they treat as adaptive are systematically deficient, arachnophobia and fear of snakes among them, are more careless by temperament and more likely to be badly hurt by accident. The three have proposed that the deficiency be classified in its own right as hypophobia, on genetic rather than clinical grounds.

Which parts of the spider do the work

Two lines of research ask what the eye is reacting to, and neither carries an author's name.

A study from 2001 found that people picked spider pictures out of an array of flowers and mushrooms faster than they picked flowers or mushrooms out of an array of spiders. The asymmetry was read as evidence that spotting a spider fast mattered more to survival than spotting a mushroom. Later replications cut the exposure to 33 milliseconds, using pictures of spiders and of flowers that resemble spiders, and still recorded distinct psychophysiological responses in phobic participants.

A 2021 paper narrowed it to features. Fear and disgust were driven mostly by:

• enlarged chelicerae
• a swollen abdomen
• the presence of body hair

An augmented reality study supported that by varying movement, hairiness and the ratio of body to legs. Chelicerae are the mouthparts, and their appearance on that list is the least intuitive finding on the page. The paper is identified only by its year.

What has been tried against arachnophobia

The first line of treatment named is systematic desensitisation, which is exposure therapy under an older label, generally preceded by relaxation training. It can be run in vivo with live spiders or in the imagination, with somebody modelling contact with a spider before the person attempts it. The technique is said to work sometimes in a single session and usually to take longer, with no trial named for either statement.

Virtual and augmented reality spiders have entered the same protocol. The article calls those techniques proven effective and cites nothing whatever for the word proven.

Then there is the suggestion that watching short clips from the Spider-Man films might reduce arachnophobia. It is written in the passive, with no researcher and no result attached, and it is the least supported claim on the page.

The external links carry exactly one clinical publication: D. Stiemerling's analysis of a spider and monster phobia, published in German in Z Psychosom Med Psychoanal in 1973. A single psychoanalytic case study from more than fifty years ago is the whole of the direct clinical citation on an article about a fear said to be among the commonest anxiety disorders there are.