There's nothing wrong with being a little weird.

Because we think of psychological disorders on a continuum, we may worry when our ways of thinking and behaving don't match up with our idealised notion of health.

But researchers say there's no need for such hang-ups - and a little "variation" is healthy.

"I would argue that there is no fixed normal," said Dr Avram Holmes, a Yale University clinical psychologist and senior author of a just-published study.


"There's a level of variability in every one of our behaviours."

Healthy variation is the raw material that natural selection feeds on, but there are plenty of reasons why evolution might not arrive at one isolated perfect version of a trait or behaviour.

"Any behaviour is neither solely negative or solely positive. There are potential benefits for both, depending on the context you're placed in."

For instance, impulsive sensation seeking, a willingness to take risks in order to have new and exciting experiences that has its roots in our evolutionary history as foragers, is often thought of negatively.

Increased sensation seeking is associated with things like substance abuse, criminality, risky sexual behaviour and physical injury.

"But if you flip it on its head and look at potential positive outcomes, those same individuals may also thrive in complex and bustling environments where it's appropriate for them to take risks and seek thrills," Holmes said.

They often have more social support, are more outgoing, and exercise more.

The same is true for anxiety.


"You might be more inhibited in social situations and you may find it harder to build friendships," Holmes said.

"However, that same anxiety, if you think of it in a workplace setting, is what motivates you to prepare for a big presentation.

"If you're in school, that's the same anxiety that motivates you to study for an exam."

He also pointed out we have more control over the contexts we're in than we tend to think, which means it's very possible to end up in an environment that favours the way our brains work.

But if variation in any given trait was normal, that raised questions about what makes for disordered behaviour, which he stressed was a very real phenomenon.

"It may be the case that if you focus on a single phenotype, there isn't a specific line that separates health from disease and that we must consider multiple phenotypes simultaneously."

Ultimately, it wasn't really appropriate to think of ourselves in terms of a single trait that was either good or bad, or healthy or unhealthy.

"This is a broader issue with our society - but we're all striving towards some artificial, archetypal ideal, whether it's physical appearance or youthfulness or intelligence or personality.

"But we need to recognise the importance of variability, both in ourselves and in the people around us. Because it does serve an adaptive purpose in our lives."

Tiny 'nanobots' combat cancer

Scientists have successfully programmed nanorobots to shrink tumours by cutting off their blood supply. Photo / 123RF
Scientists have successfully programmed nanorobots to shrink tumours by cutting off their blood supply. Photo / 123RF

Scientists have successfully programmed nanorobots to shrink tumours by cutting off their blood supply.

"We have developed the first fully autonomous, DNA robotic system for a very precise drug design and targeted cancer therapy," said Arizona State University's Dr Hao Yan, who just demonstrated the technology in mammals and mouse models.

"Moreover, this technology is a strategy that can be used for many types of cancer, since all solid tumour-feeding blood vessels are essentially the same."

Yan is an expert in the field of "DNA origami", which in the past two decades has developed atomic-scale manufacturing to build more and more complex structures.

The bricks to build their structures come from DNA, which can self-fold into all sorts of shapes and sizes - all at a scale 1000 times smaller than the width of a human hair - in the hopes of one day revolutionising computing, electronics and medicine.

That day may be coming faster than anticipated.

Nanomedicine is a new branch of medicine that seeks to combine the promise of nanotechnology to open up entirely new avenues for treatments, such as making minuscule, molecule-sized nanoparticles to diagnose and treat difficult diseases, especially cancer.

Until now, the challenge to advancing nanomedicine has been designing, building and carefully controlling nanorobots that actively seek and destroy cancerous tumours - while not harming any healthy cells.

The international team of researchers overcame this problem by using a seemingly simple strategy to selectively seek and starve a tumour.

"These nanorobots can be programmed to transport molecular payloads and cause onsite tumour blood supply blockages, which can lead to tissue death and shrink the tumour," said collaborator Baoquan Ding, a professor at China's National Centre for Nanoscience and Technology.

Yan and his collaborators are seeking out clinical partners to further develop this technology.

"I think we are much closer to real, practical medical applications of the technology," Yan said.

"Combinations of different rationally designed nanorobots carrying various agents may help to accomplish the ultimate goal of cancer research."