There are many theories on the cause of autism, a developmental disorder that causes a wide variety of abnormalities in social skills, language skills and behaviour in people. These theories range from the measles vaccination to gene mutations and even celiac disease.
But, as the world commemorates the eighth annual World Autism Awareness Day on Thursday April 2, South African-born neuroscientist Professor Henry Markram says the cause is more likely due to the overstimulation of our brains.
Markram should know, he has a personal link to the condition – his son Kai.
"I always wanted to understand the brain, but when Kai came along, I realised that neuroscience needs to move much faster and in new ways if we want any chance at understanding the brain and its diseases," he says.
"So what it has done is give me a massive push not to waste a second in getting to the bottom of this amazing divergent brain."
Born in the Kalahari, Markram, who is now based in Switzerland, credits South African institutions for shaping the way he thinks about the brain.
"I was born in the Kalahari and I have deep memories and impressions from my childhood there. I went to school at Kearsney College in Durban.
"I wanted to become a psychiatrist, but the laboratories right next to the hospital were so enticing that I started digging into the inner workings of the brain and soon left medicine to dedicate my life to understanding how the brain is designed and works."
Markram's 'intense world theory'
Markram, a professor of neuroscience at the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, is one of the originators of the "intense world theory", which upends conventional understanding of autism spectrum disorder.
His theory posits that autism is related to an overstimulated brain, and the inability of those on the spectrum to cope with the flood of incoming sensory input.
In a modern world populated by the constant stimulation of television, advertising, cellular phones and social media, its hard even for those who are not autistic to feel exhaustion from sensory bombardment.
This theory is often used to suggest that the rise in autism is a sign of human evolution attempting to cope with a culture that is overloading the senses.
Markram, who is also behind a billion-dollar project to build a supercomputer version of the human brain, says evolution is characterised by "scouts" that break through norms.
"Most scouts don’t survive, but the ones that do lead the way for the rest of humanity."
He says autism is a more complex form of evolution since it is not only genetic, but could also be caused by an insult during pregnancy, like drugs or alcohol or even traumatic events during brain formation in the womb.
"We think that, for a child where autism has been triggered during pregnancy, the world is extremely intense - like dialing up the volume on the radio to full blast, changing stations every second, turning up the lights to maximum, increasing the intensity of all the colours, the smells," Markram says.
"They feel the slightest touch as if sand paper had scraped their skin. When people speak to them it is like the world is screaming at you. When they look into someone's eyes, they see much deeper into people than 'neurotypicals' and it is better to look away.
Those with autism are the scouts of humanity
"When they think about someone they become so focused that the world disappears and they can travel in their brain to places where neurotypicals can never reach.
"They can see patterns in numbers, shapes, in life, and many more. Each one is unique in that their personality is massively exaggerated, so they each have their own specific preference or speciality."
This means that those on the autistic spectrum can be thought of us "scouts of humanity" since they go to the frontiers of what humans feel and think.
"If humanity treats autism as a mental retardation as they have been doing for decades, then humanity will lose all that they offer us.”
Markram says autistic children can teach the "normals" of the world the way forward, especially with regards to empathy.
"Conventional research has for decades claimed that they have no empathy. In fact their level of empathy is so amplified that they must withdraw into a bubble, away from the world, because it is too painful to feel so much of what others feel," he says.
"The lesson is that the level of empathy of the normals of the world has a very long way to evolve."
The rise and rise of autism
According to an article by Chris Bateman in the SA Medical Journal's Izindaba in 2013, the United States department of health estimated that cases of autism have increased over 500 percent over the last few years.
He also mentioned research that projects that within a decade 1 in 22 people could be diagnosed as autistic.
Bateman said in the article that in the Western Cape approximately 10 children a week are diagnosed with mild autism spectrum disorder. The article however does acknowledge that accurate autism statistics for South Africa are "hard to come by".
Markram’s "intense world theory" has a number of critics, many of whom disagree with the idea that if parents created a filtered environment for an autistic child, you could end up with a "genius" - like Dustin Hoffman's Academy Award-winning performance as an autistic savant in the 1988 film Rain Man.
Autism South Africa director Sandy Usswald says there are numerous theories as to the cause of autism and the appropriate ways to raise autistic children.
"The bottom line is research has not yet come up with reliable and valid answers. At Autism South Africa we always advise families to do their research and rely on evidence based approaches," she says.
"There are anecdotal stories of alternative interventions being successful and as long as the method poses no risk of harm, if it works for the particular person that is what matters.
"We cannot however support or align ourselves with unsubstantiated theories that are not supported by research. When that day comes we will embrace the answers as I am sure our families and community will."
Markram says the theory is not about linking the worth of anyone to special abilities, but about helping autistic children cope with an intense world.
"If you can even appreciate a minute fraction of the pain that they suffer when born into an intense world, you will also want to do anything and everything to help them cope.
"They are all geniuses no matter what you do, but helping them cope with an intense world just equips them to be themselves. An organised, filtered beginning to life after birth just gives the brain the time that it needs to get ready to deal with the intense world.
"The Kalahari was my filtered environment as I grew up. Such structured, calm and predictable environments are good for anyone, not just autistic children.
"This is going to become even more important as the world we all live in becomes exponentially more intense as human society evolves."
Watch: Neuroscientist Henry Markram talks about The Human Brain Project, consciousness, intelligence and collective autism.