When a baby fuses or cries,

exhausted parents may wish they could know what's going on inside their baby's brain.

When how scientists hope clues could come with the help of a

wearable brain imaging device, it looks like a cap and can track cognitive

functions and one day it may help identify early signs of autism or ADHD.

I TV science correspondent Martin Stu has the story.

It's easy enough to tell when babies like Victor aren't happy,

not so easy to know exactly why.

They can't talk to tell us what's going on inside their head and

brain scans until now have often involved full sedation and an MRI.

That's where this wearable scanner comes in.

The cap has lots of these hexagons in it that shine light into the head

and measure how much light reflects back off the brain.

And so by seeing the differences in levels of light that reflect back off the brain, we can map

where brain activity is happening in the brain.

The beams, whilst completely harmless, are illuminating.

By comparing brain activity with and without social stimulation,

scientists observed different levels of activity in the prefrontal cortex,

suggesting babies as young as five months old are already becoming

emotionally intelligent.

So one of the things that we see is much greater activation in social situations.

Some areas of the brain are much more active when babies are watching people singing to them

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