02/04/2013 01:52 BST | Updated 02/04/2013 08:42 BST

World Autism Awareness Day: How To Spot The Signs In Adults (PICTURES)

When it comes to autism, awareness of the condition and its effects on a person's behaviour has risen dramatically in recent decades.

However on April 2, World Autism Awareness Day, campaigners will still be working hard to address misconceptions about a condition that affects more than half a million people in the UK.

Since November last year, The National Autistic Society has been campaigning to dispel myths (such as the ideas that autism only affects children or that all people with the condition are geniuses), via a social media campaigns -- see tweets below.

A key message of their awareness-raising mission has been about diagnosis, as research suggests that most adults with the condition are unaware of it.

A survey conducted in England by the University of Leicester in 2011 found that not a single person identified with autism or asperger’s syndrome actually knew they had the condition.

What are the most commons signs of autism in adults? Find out below..

Photo gallery Signs Of Autism In Adults See Gallery

The research also revealed that autism appears to be commoner in males, those without higher educational qualifications, and among individuals living in social (government financed) housing.

In a blog recently published on The Huffington Post, Hannah Gal reveals one young male student's struggle with autism.

"There was also a time when while standing on a platform waiting for a train, an announcement instructed passengers to stay behind the yellow line. I just couldn't figure out how I am meant to get on the train with the yellow line still there."

"Teachers may have found it more difficult due to my literal thinking. For example if they asked me to 'pull my socks up', I would have literally done just that, without meaning to be cheeky or insolent."

To find out more about autism and World Autism Day visit The National Autistic Society website or follow them on Facebook here.ware