Across the lifespan, social tactile interactions
have been shown to benefit an individuals
physical health and psychological wellbeing.
In just one example, pre-term infants become
healthier and grow quicker as a result of
skin-to-skin contact with a parent or caregiver.
There are two different types of touch, that
a signalled by different nerves in the skin.
The first allows us to distinguish between
objects we come into contact with, and to
locate touch on the skin. These are signalled
by relatively large diameter nerves, which
send signals rapidly to the brain.
The second type of touch is the emotional
information about a sensation.
These are conveyed by smaller diameter, slow conducting nerves, that send signals slowly to the brain.
Now typically these C-Type fibres are associated
with signalling the emotional value of pain
and itch. However, it's a more recently discovered
subtype of these C Fibres that I'm most interested in.
These C-Tactile afferents, or CTs, are very
picky about the type of touch they respond to.
There are 3 things that keep them happy.
The touch should be slow moving, not static.
The touch should be gentle, not foreceful,
and the temperature of the touch should be around 30 degrees [C].
We know this because direct measurements from
these nerves showed that their activation
is directly tied to these criteria.
Now 32 degrees [C] is the temperature of human
skin. So taken together, this suggests that
these CTs, have evolved to signal, the rewarding
value of social-tactile interactions - like a gentle caress.
Now - Why is this important? Well - touch
is a key regulator of our emotional arousal,
and plays an integral role in our early social
development.
For instance, a crying baby is comforted with
the touch of an adult. Someone in emotional
distress is comforted by a hug. An injured
child is soothed by contact with a parent.
But what if we didn't perceive comfort or
reprieve from these negative emotional situations.
Where would that leave us?
Imagine if we process this type of touch
differently. If the typically pleasant and
painless sensations that we perceive when
CTs are active was painful and unpleasant.
What consequences would this have for a developing infant?
Autism is prolific developmental condition
that affects an individual for their entire
life.
Children later diagnosed with Autism,
typically perceive gentle touch as aversive.
It's hypothesised that this would have a negative
impact on their social and emotional development.
The aim of my research is to discover how
individuals with autism process CT touch.
Early evidence suggests there are vast neurological
differences
between the autistic and healthy brain.
Using brain imaging techniques, and physiological
measures such as heart rate and arousal,
I aim to measure the difference between autistic
and healthy individuals during CT touch.
This will enhance our knowledge of CT touch,
and the role that it plays in typical and atypical development.
Thank You.
[APPLAUSE]
