Profiling Williams Syndrome

Melanie Porter

The universal profile of Williams Syndrome could well be revised following the findings of Macquarie University PhD student and Clinical Neuropsychologist, Melanie Porter.

Williams Syndrome, which affects approximately one in 20,000 people, is a rare genetic disorder resulting from abnormalities on chromosome 7.

People with Williams Syndrome are reported to show excessively sociable personalities, good socio-emotion processing skills and a 'syndrome-specific' cognitive profile with strengths in verbal skills and a weakness in nonverbal abilities. This ‘universal’ profile was something that appeared flawed early in Porter’s research.

“When I started to interact with families and children with Williams Syndrome I noticed that a lot of them were quite variable in their thinking functions,” says Porter. “The first thing that I did was to look if there was a single profile for Williams Syndrome. I found that there wasn’t and we (Porter and her supervisor Professor Max Coltheart) came up with what we called subgroups of people with Williams Syndrome.”

Through her study of 31 Williams Syndrome participants, Porter established at least four separate subgroups.

While Porter’s thesis was originally based solely on Williams Syndrome, she was encouraged by her initial findings to draw comparisons between this disorder and Autism. Williams Syndrome and Autism then expanded to include Down Syndrome and Asperger Syndrome.

Porter’s research saw her travel throughout New South Wales and South Australia. She met with people from the ages of 4 to 45 and generally completed about five sessions with each participant, totalling around 15 hours each. The travel across the country did prove costly, but Porter was aided by two fellowships, one from the Institute of Psychiatry and the other from the Australian Rotary Health Research Fund.

Apart from her initial finding that not everyone with Williams Syndrome fits into the universal profile, Porter also discovered similarities between some strands of Autism and Williams Syndrome.

“Apart from thinking functions (attention, memory, problem solving, spatial abilities, and language abilities), I also looked at social and emotional processing as well as theory of mind,” explains Porter.

Theory of mind is the ability that children have to understand that other people have mental states such as thoughts, desires, emotions, and using that information to explain and predict behaviour.

“One of the theories is that people with Autism lack a theory of mind and those with Williams Syndrome have good theory of mind, but my research showed that some actually had very poor theory of mind and poor emotion recognition,” she says.

Porter also looked at spatial procession in the three clinical populations, and found that those with Autism and Williams Syndrome show more attention to detail than those with Down Syndrome.

“If you asked a child with Williams Syndrome to copy a drawing of a house they would draw all the details, windows, doors etc but there would be no order,” she says. “We found that Down Syndrome participants showed the opposite, they would draw the outline of a house and not the details.”

Graduation will not mark the end of Porter’s involvement and interest in Williams Syndrome. She is currently awaiting funding for a joint Macquarie Centre for Cognitive Science (MACCS) and Garvan Institute project that will look into whether gene abnormalities directly correlate with cognitive and social abnormalities of a particular Williams Syndrome subgroup.

For further information please contact Porter’s supervisor Professor Max Coltheart: max.coltheart@mq.edu.au or visit the MACCS website: http://www.maccs.mq.edu.au

December 2004

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