What is Flickering? or the Flicker Rate? October 5, 2006Posted by healthyself in 16-25 Hz, 3-60 Hz, 50 Hz, 60 Hz, Adolescents, Bioeffects, Biological Effects, Blogroll, Cell phone safety, Cell Phones, Children's health, Chromosomal damage, Chronic Fatigue, Definitions, Electrical Components, Electrical Pulses, Electrical Wiring, Electromagnetic Communications, Electromagnetic pollution, Electromagnetic waves, EMF's, Environment, Epilepsy, Exposure, Eyes, Flickering, Frequencies, GHz, Health related, HOuseholds, Hz, Interdisciplinary, Lifestyle, light beam, nerves, Oscillate, Photosensitive, Pulsed Radiation, radiation, School administrators, Spacial Contrast Patterns, Symptoms, Teenagers, Telephony, Toxic Interactions.
“Flickering is the opposing changes in intensity of luminosity. This is usually caused by flashing, but can also be caused by spatial contrast patterns that oscillate at dangerous frequencies; the type of images that people create to deliberately stimulate a response in the recipient that makes them believe the image is moving or changing. For people with photosensitive epilepsy, flickering causes many of the nerve cells that process visual stimuli to all fire at once, resulting in a seizure”
“Along with the frequency of the flickering, the size and luminous intensity of the stimuli is significant for people with photosensitive epilepsy. The greater the intensity and larger the size of the stimuli, the greater the danger of provoking seizures caused by flickering at dangerous frequencies.”
“The colour red is particularly dangerous due to its longer wavelength that stimulates cones in the retina. There have been cases where photosensitive epileptic seizures have been triggered by cyclists while setting up the red flashing rear lights on their bicycle. Even when there is no perceived difference in the luminosity of the contrasting colours, red flickering is far more likely to cause seizures than other colours.”
“Television programmes are thought to be the most common cause for triggering photosensitive epileptic seizures. The most famous incident of photosensitive epilepsy caused by a television programme is the Pokémon episode, Electronic Soldier Porygon , which was aired in Japan in 1997. Nearly 700 children were admitted to hospital through photosensitive epilepsy that was thought to have been induced by the episode.”
People with photosensitive epilepsy can have seizures triggered by flickering or flashing in the 4 to 59 flashes per second (Hertz) range with a peak sensitivity at 20 flashes per second as well as quick changes from dark to light (like strobe lights).When content violates either the general flash threshold or the red flash threshold , users are warned in a way that they can avoid it
Content does not violate the general flash threshold or red flash threshold
“Allowing people to choose whether or not they receive the content is better than not providing a warning, but there are other factors to consider. The first is that as photosensitive epilepsy is most common in children, it could be that they don’t understand or appreciate the significance of the warning. It isn’t just children; people with reading difficulties or speakers of languages other than the language of the warning may also inadvertently be exposed to content that could induce seizures.”
“Although the size of the stimuli is significant, there is still a danger of material that is considered to be safe being changed by the visitor. For example, low vision users increasing the size of flickering material, or someone leaning in close to the screen.”
“The safest way to avoid causing photosensitive epilepsy is to completely avoid creating web content that flickers.”
“People with photosensitive epilepsy who suddenly find themselves exposed to material that could trigger a seizure should immediately cover one eye with the palm of their hand to reduce the number of brain cells that are stimulated by the flickering content, and either close the page or navigate away from the page.”
“Photosensitive epilepsy is a form of epilepsy that is triggered by visual stimuli, such as flickering or high contrast oscillating patterns, and it’s believed that around 3% to 5% of people with epilepsy are susceptible to photosensitive material. Photosensitive epilepsy is usually triggered where the flicker rate is between 16Hz to 25Hz, although it’s not uncommon for seizures to be triggered by flicker rates between 3Hz to 60Hz. The condition most commonly effects children, and is usually developed between the ages of 9 and 15 years, and most prevalent in females.”
Computer Monitors Affect the Nervous System October 1, 2006Posted by healthyself in 100 Hz, 60 Hz, 85 Hz, Attention, Biological Effects, Blogroll, Brain, Cell phone safety, Central Nervous System, Electrical Components, Electrical Pulses, Electrical Surges, Electromagetic pollution, Electromagnetic Communications, Electromagnetic Interference, Electromagnetic waves, Electrosensitivity, Electrosmog, ELF, EMF Research, Environment, Exposure, Fatigue, Frequencies, Health related, HOuseholds, Hz, Inner Agitation, Lifestyle, Light, light beam, Long Term Health Risks, Men's Health, Microwave exposure, Optical, Pulsed Radiation, Pulses, radiation, Research Needed, Short-sightedness, teeth grinding, Women's Health, Workplace, yawning.
CRT Users Beware!
“Many people are still using CRT monitors set at 60 Hz or 85 Hz around the world….What they don’t realise is that these refresh levels have side-effects of inducing tiredness, yawning, short-sightedness and the most destructive of which is tooth grinding at night. Unstable images on a CRT can induce tooth grinding subsconciously at night, since an unstable flashing image is disturbing to the brain’s nervous system.”
“Tooth griding permanently destroys your teeth and you can’t get back lost enamel tissue. Restoration of damaged teeth is extremely expensive, more than your monitor and your damaged teeth will have an effect on your health, as teeth is the major organ of healthy digestion. Digestion begins in the mouth as the proper breakdown of food. If you can’t digest your food properly, then you will not last long on this Earth.”
“New CRT TVs (not monitors) are widely advertised at being 100 Hz.”
“Why we are still stuck at a so-called safety standard of 85 Hz, which still induces the CRT side-effects as mentioned above is amazing….The bottom line is to see if you can set your CRT to at least 100 Hz and take to regular breaks from the screen….Breaks are important for LCD users as well, since human eyes were not designed to stare and focus at a light source for a long time.”