17 Aug 2022

Neurodiversity - unlocking the causes and dispelling the myths

From Nine To Noon, 9:20 am on 17 August 2022

We are all wired differently. Dyslexia, dyscalculia, ADHD and autism spectrum conditions are all variations that can exist in our brains. 

Researchers are trying to gain a better understanding of the causes of neurodiversity through looking at genetic and environmental factors along with new scanning techniques which allow them to watch the brain at work. 

Everyone's brain works a little differently. According to the neurodiversity paradigm, this isn't necessarily a bad thing. Society can benefit from the strengths and accommodate the weaknesses of each person.

Photo: MissLunaRose12, CC BY-SA 4.0

Neurodiversity is an umbrella term, says professor Karen Waldie from Auckland University's School of Psychology and Centre for Brain Research. 

“It refers to variation in the brain structure and function and this can affect cognitive abilities such as language and reading, attention and self-control and/or social communication and interaction.” 

While it’s an umbrella term, it does include neurodevelopmental conditions such as dyslexia, dyscalculia, ADHD and autism. 

It’s a way to distinguish conditions someone is born with from those acquired through brain injury. 

These are very complex conditions involving numerous genes, Waldie says. 

To observe brain activity, the researchers use functional magnetic resonance imaging predominantly and sometimes EEG. 

“People are probably aware of the typical MRI, which give us just a picture of the structure of the brain and only a few scanners in New Zealand are functional, so that basically tracks the oxygenated blood as people are in the scanner performing mental tasks.” 

Someone partaking in a dyslexia study may be asked to do different language and reading tasks. Through scanning Waldie will be able to see what parts of the brain are active and which are inactive. 

The researchers have been able to show parts of the brain that should be active in neurotypical people when reading are not active in the dyslexic brain, she says. 

Particularly in the superior temporal lobe in the left hemisphere, she says. Instead, they see a lot of compensatory activity, areas in the right hemisphere that are active. 

“We’re able to correlate those areas with performance and we’re finding that these areas that are helping out are indeed helping dyslexic people to read.” 

During an ADHD study, participants will do a decision-making task and activities will be focused on the prefrontal cortex. “And then we can see our individuals if they’re activating certain areas.” 

The prefrontal cortex is important for planning, self-control, attention and decision making, she says. 

“What we see when we have people with ADHD in the scanner performing a mental task that involves decisions, we see much much less activity in the prefrontal cortex compared to neuro-typical people.” 

The techniques can’t yet be used in a personalised medicine, instead researchers rely on many participants to allow them to see statistically meaningful results, Waldie says. 

She hopes in the future there is better identification and diagnosis. 

It wasn’t until 2007, she says, that the Ministry of Education officially acknowledged dyslexia. 

“I think we’re a little bit behind in that regard, looking at neurodiversity as something that we’re born with, that is different in brain structure and function and that it needs specialised help,” she says. 

“I know a lot of parents are out there really concerned that in New Zealand we’re not doing enough to identify and diagnose because that’s the first step before we can help with remediation and treatment if needed.” 

But there’s always pros and cons to early identification, she says. 

“There’s a risk of pathologising people, stigma of being labeled because these aren’t diseases – we have to be careful with that. 

“On the other hand, knowledge is power and knowing what your child has, or what you have or what your partner has, it’s a way of owning it and it’s a way of being able to get more information.” 

Knowing your strengths and difficulties is really powerful, she says.