Download FND app Android Aapp IoS App
FND Links Feedback Donate Language
  • English
Home / Symptoms / FND Symptoms / Visual Symptoms

Visual Symptoms

Visual symptoms can be functional or dissociative. The following types of symptom are quite common:

Visual blurring

Typically people complain that their vision intermittently goes “blurry” and they have to screw up their eyes to make things come back to normal. Sometimes the vision may even be double. This symptom is often due to “convergence spasm”. This is when one of the eyes is too actively ‘turning in’ towards the nose. Convergence is a normal eye movement but sometimes it becomes hyperactive in people with FND or functional neurological symptoms.

Tubular fields are a sign of functional visual symptoms

Light Sensitivity (Photophobia)

This is common in people with chronic fatigue syndrome. It may also occur in people with functional weakness and sensory symptoms. Often people are more light-sensitive on the same side as the weakness. Strong light may even make the weakness worse.

A natural response to this symptom is often to wear dark glasses. The trouble with this is that this tends to make the eyes even more sensitive to light. The best approach to light sensitivity is to gradually expose the eyes to more and more light over time. This may need to be done gradually.

Reduced Vision

More rarely people may experience significant loss of vision in one or both eyes. Occasionally people cannot see anything at all. In this situation the diagnosis of functional blindness will be made by tests that show the pupils are reacting normally, the eyes are reacting to a moving stimulus and the parts of the brain to do with vision are all intact.

People with functional visual symptoms may have clinical findings such as a ‘tubular field defect’ or spiral fields when they undergo visual field testing (See picture below).

“Spiral fields” are seen on formal visual field testing and can be a sign of functional visual symptoms

The commonest type of functional visual impairment is usually only experienced by people as intermittent blurring – or not seeing so well out of one eye when they cover the other one. Its especially common that someones vision seems much worse when they do an eye test or are examined by a doctor than it is in day to day life. It’s a common feature of many FND symptoms that they are worse when someone is focusing on them like this.

There isn’t much research on treatment for functional visual loss.

I wrote up my experience of treating two patients with functional blindness in this article:

Seeing again: treatment of functional visual loss
Jing Ming Yeo, Alan Carson, Jon Stone. Practical Neurology 2019: 19: 168-72

“Visual Snow” and Visual Persistence Phenomena

Sometimes people become aware of a snowlike effect in their vision. This could be due to an eye or brain disorder but it can also be a normal phenomenon. If anyone looks at a bright background they may become aware of a fuzzy, ‘static’ with a sense that things are moving around. In some people this persists. Normally the brain blocks out this additional visual information. Research has linked visual snow to migraine.

People also can become aware of the persistence of visual images, especially after they have been looking at something for a while or if they are trying to follow a rapidly moving object. Like visual snow, it’s really important to exclude a neurological or ophthalmological cause for this but it can occur, as part of a functional disorder. It may be due to the same problem of the normal ‘filtering’ mechanism in the brain which blocks out the excess visual information going wrong.

An organisation for people with visual snow is at

best male testosterone booster viagra vs sildenafil how to boost male libido dependency on male enhancement pills healthy male enhancement pills will extenze help me get hard cialis package insert extenze male enhancement pills walmart testosterone booster best you want penis enhancement pills over the counter erectile dysfunction pills cvs best libido booster for male how to raise libido male do penis pills eben work ergogenic testosterone booster gnc male enhancement products male enhancement sleeve ed pills gnc whats the price of viagra pills to increase penis male enhancement pills cialis over the counter male enhancers natural sexual stamina do testosterone pills work for ftm erection enhancing drugs 100mg viagra blue diamond male enhancement pill which is cheaper viagra or cialis ht rush testosterone booster reviews hardknight male enhancement side effects thrust testosterone booster reviews how to increase a mans libido naturally male sex enhancement gel on amazon when she took male enhancement pills gas station testosterone pills what to take to increase libido

home window replacement 59 x 33 window replacement rancho cucamonga family owned home window replacement home window replacement 77433 emergency home window replacement humble tx window replacement charlotte nc replacement casement windows custom made replacement windows best replacement window warranty video install replacement window mobile home vinyl insert replacement windows window installation clips how to replace door screen window repair parts flip folder replacement windows house window repair parts replacement windows dallas tx window shades repair window sash balance replacement how to measure for a replacement window window weight replacement spring window repair palm bay fl window shields replace window repair bradenton fl triple a glass repair home window repair dripping springs tx egress window installation minneapolis mn window replacement grants for pensioners window installation deals pella window sash lock replacement window repair gilbert az window rubber seal replacement residential window frame repair near me austin window screen repair windows replacement lexington costco window replacement reviews

cbd oil on amazon cbd oil and plaque build up in legs nutra pure cbd oil best cbd oil for pain cbd for anxiety and stress does cbd oil reduce pain benefits of cbd oil from hemp rick simpson hemp oil youtube hemp oil vitamin e making cbd oil with mct oil illegal for cbd oil to be dietary supplement cbd oil broadway hemp oil pure cbd oil from hemp recipes using cannabis coconut oil melodi cbd oil can you buy cbd oil in new york cbd oil can help the way you sleep cbd oil ganglion cyst how fast does cbd oil work under tongue buy cbd oil venice beach ca can cbd oil treat pain wholesale buying cbd oil how cbd oil cures cancer organi bloom cbd oil will cbd oil react with nsaids cbd oil on planes ojai cbd oil reviews cbd oil prescribed by duke neurologist dr cbd oil for tfcc underground cbd oil in abingdon va cbd oil sexual stimulant what is the best cbd oil for multiple sclerosis 5000mg cbd oil blue label what does cbd oil do neuropsthy amazon cbd oil tincture coa cbd oil doze

weight loss doctors in nj demi lovato weight loss n acetyl cysteine weight loss raw vegan weight loss 1 month how to lose weight on lexapro free trial phentermine diet pills norex diet pills weight lifting for weight loss female free samples of weight loss pills does pilates help you lose weight does diet pills affect birth control before and after weight loss men free weight loss pills samples with free shipping what is the best diet pills to lose weight my diet pills phen phen weight loss pills african weight loss pills highly effective weight loss pills nitro weight loss pills ronnie from jersey shore weight loss pills yes you can diet plan pills diet pills to suppress appetite star diet pills salt keto diet nidora diet pills philippines diet pills with glucomannan duromine diet pills phen diet pills cellucor hd diet pills jennie garth weight loss what are good diet pills that work fast ice pack for weight loss review keto diet herbalife pills for weight loss is cottage cheese on keto diet xm3 diet pills