The conflict between this and other cues to spatial orientation causes a disorientation that is true flicker vertigo. The brain "believing" that the visual field is moving across the retina interprets this as meaning that the body is moving in the visual environment (rather than the visual environment is moving across a steady body). As the sun shines through the disc, the eye sees a large shadow sweeping across the visual field rapidly and repetitively. The second problem is a separate one and is nothing but an optical illusion that can be very disorientating. If you do get epileptiform waveforms, you have a greater than 1% per annum chance of having a seizure and are therefore not considered medically fit. The usual frequency range that causes problems is 1 to 30 Hz and in the UK an EEG with photic stimulation in this range forms part of the initial Class 1 medical exam. Some individuals (the CAA quotes 0.5% of applicants) are susceptible. The first problem is induction of an epileptic electrical activity in the brain by a bright flashing light. Quite a few of the posts confuse the two. There are 2 separate problems that can both be caused by bright sunlight shining through the disc. I don't recall the CAA doing this.Īny flying AME out there? Roger Green or anybody? Usually these guys don't get to fly again once their companies hear of an occurrence sad for them as it affects their job.įor aircrew the matter would be serious though I remember the Dutch RLD tests pilots for sensitivity to flicker effect as part of the initial aircrew medical. The pilot can remove the source of the problem simply by moving the pax to another seat or by changing course to take him out of the sun. Don't know if it happens on military Chinooks. I never saw it on the 61 or the 76 nor on any Bell I flew. You could say that this might happen to anybody who sat in a Chinook for five hours but that would be unkind. The frequency of the flicker ing sun through the large, slow-moving rotors seems to upset the brain's natural frequencies - alpha waves I believe the seizure that follows is extremely alarming to both the victim and to those sitting nearby. It is related to epilepsy I believe some people are more prone than others. It explores how filmmakers have learned to take advantage of the tricks our minds are already playing on us in real life.Some of our pax in the North Sea used to experience this on Chinook flights when sitting next to the window on the sunny side. His book Flicker:Your Brain on Movies (2014) is one of the first books on film-making by a brain scientist. Prof Zacks is an experimental neuroscientist and Associate Chair of Psychological and Brain Sciences at Washington University in Saint Louis. Whether you are a fan of films, of neuroscience, or both, some of the answers will surprise you.
Some of the questions he will take on: How can mere images make us flinch, laugh, cry, tap our toes? What’s the difference between what happened in a movie and what happened in real life-and can we always tell the difference? How do our brains process film editing? In this talk, visiting Professor Jeff Zacks from the Washington University in Saint Louis, will draw on the history of cinema and the latest research in neuroscience and psychology to explain what happens in your head when you sit down in the theatre and the lights go out.
They reshape our emotions and worldviews-but why?
How is it that a patch of flickering light on a wall can produce experiences that engage our imaginations and can feel totally real?įrom the vertigo of a skydive to the emotional charge of an unexpected victory or defeat, movies give us some of our most vivid experiences and lasting memories.