Why does looking at the stripes give us a headache?

One morning when you wake up, you are trying to choose the right clothes to wear, your eyes suddenly stop on the plaid T-shirt you like. You will spend a few seconds staring at it while still choosing what to wear, you will probably feel your eyes get tired, uncomfortable feeling, even stinging in the temples.

This is not new to anyone, you may have felt it at some point in the past when looking at tall buildings with repetitive motifs, or even patterns. tiles on several floors of the house. But have you ever wondered why this happens, what's wrong when you look at those stripes or patterns that give you headaches or eye discomfort. Let's find out through the following article.

The difference between natural and artificial visual stimuli

Our surroundings include a wide variety of visual stimuli - both natural and man-made, yet the images or objects that are reported to be the most irritating to the eye are almost always of origin. artificial. So why do natural scenes and objects rarely cause the same discomfort to the eyes? The answer lies in the visual properties of these images or objects. Man-made objects have certain statistical properties that distinguish them from natural scenes and objects.

Textures that irritate our eyes are almost always man-made, such as Venetian blinds.

Natural excitations also obey certain laws, in which contrast energy and spatial frequency will be inversely related. That is, your visual system is only accustomed to being exposed to stimuli with an inverse combination of contrasting energies and spatial frequencies, where one is high then the other is low and vice versa. Artificial stimuli often violate this rule, in that they are often high-contrast energies at mid-range spatial frequencies and are stimuli commonly reported to cause visual disturbance.

How the brain handles artificial stimuli

Scientists conducted a study that looked at the brain's oxygen metabolism while participants viewed both natural and artificial images with different statistical properties. The more the subjects differed in visual statistical properties from natural stimuli, the higher the participants' level of discomfort. On the other hand, metabolic activity in the brain also correlates with levels of discomfort. The stimuli that cause the most discomfort are thought to cause a higher need for metabolic activity in the visual regions of the brain. This also clearly shows that the stripes represent statistical properties that are not naturally present and also place higher metabolic demands on our brain, causing discomfort to watch them.

Why do some artificial urban stimuli cause headaches or migraines?

Scientists have studied the human brain's responses to vertical lines to understand what in the brain causes unpleasant sensations. Using magnetic electroencephalography (MEG), experts analyzed human brain activity while viewing patterns of stripes at various frequencies. Interestingly, the scientists found that viewing these samples at a certain frequency caused gamma fluctuations in the visual regions of the brain just as in people reporting discomfort and delusions. Obviously, the presence of these gamma fluctuations can cause discomfort, dizziness, even headaches or migraines before the response to the stripes.

Many people experience headaches or migraines in response to the stripes.

A recent study confirmed this suspicion as well, where they investigated visual images and their probability of stimulating patients with photosensitive epilepsy. In this investigation, they found that certain images were more likely to produce gamma oscillations in certain populations of neurons in the visual region of the brain. These same images also show a high risk of photosensitive seizures.

The gamma oscillations that form in the brain in response to viewing the stripes can trigger seizures.

These evidences further demonstrate that gamma oscillations are responsible for seizures in epileptic patients. These gamma oscillations when stimulated in the brains of normal people when they look at the stripes cause headaches.

In short, the uncomfortable feeling in your eyes when viewing the stripes is the result of the brain being confronted with problems processing the unnatural stimuli that occur in our world. It is explained similarly to your computer crashing due to running software that it was not built to support.