By the time he was one year old, Aidan Na (right) could recognise and recite the alphabet.
And before he turned two, he could already count up to 100 and spoke in full sentences.
These days, the 3½-year-old is exploring complex polygons and 3-D shapes while his classmates in nursery are learning about basic shapes like squares and triangles.
Aidan's 37-year-old father, Mr Allen Na, who is a regional market development manager in the life sciences and biotechnology sector, says that his child's "quick development pace made us curious to know how he would fare in an IQ test".
Aidan's mother, Madam Vivian Yeo, is a clinical research manager with a pharmaceutical company.
"He would observe us unlocking our smartphones and memorise the password combination so that he could access YouTube to watch videos relating to alphabets, shapes and numbers.
"He was even able to navigate the different channels with the search tool independently," says the proud father, who paid $600 for the IQ test.
The test scores indicate that Aidan has an IQ of 142 - which is in the 99.7th percentile of his age group - his father tells The New Paper on Sunday.
Dr Lian Wee Bin, paediatrician and neonatologist at SpecialKids Child Health and Development Clinic at Thomson Plaza, says that based on these anecdotes, Aidan's development is "unusually fast for his age".
"Kids in Singapore start to pick up recognition of letters and numbers when they are about two to three years old, though they often do not perfect it till later," she points out.
The test Aidan took is one of three tests that Mensa, which touts itself as the largest and oldest high IQ society in the world, recognises.
Called the Stanford-Binet Intelligence Scales, Fifth Edition (SB-5), testers says it can work for kids as young as two to adults as old as 80.
Examples of tasks that a child like Aidan would have done for the test include studying pictures showing people in odd situations and pointing out the absurdity, counting components in 3D block structures, among others, says Ms Lesley Sword, a consultant from Australia who specialises in the psychology of the gifted.
Mr Na says he has applied for Aidan to join the society, but has yet to fill in the membership forms.
A spokesman from Mensa Singapore confirmed that Aidan's IQ score qualifies him to join Mensa.
Aidan has a five-year-old sister, Charlotte. But unlike her brother, Charlotte was not tested by a psychologist, as her development milestones appeared to be line with what is expected of children her age.
The siblings interact very well, and in some ways behave more like friends despite their age gap.
Even though his IQ score categorises him as a gifted child, his parents intend to put him through the mainstream education system here, but hope he can be enrolled into the gifted education programme.
"Children like him require special attention and educational resources to thrive, which are often not provided in mainstream schools. We hope that Mensa will be able to provide the support network and intellectual resources for our child," he says.
His expectations: "That he grows up to be an honest, productive and hardworking individual.
"We hope he follows his passion when it comes to a career and uses the gift he's been given to contribute to society," says Mr Na.
The IQ test that Aidan took is called the Stanford-Binet Intelligence Scales, which is in its fifth edition.
In Singapore, the cost of an IQ test, typically administered by a registered psychologist, starts at $600, says a spokesman at Gifted Academy, a centre providing such tests here.
"SB-5 is frequently used as part of a battery of assessments to help diagnose developmental disabilities as well as giftedness," says Ms Cheryl Chia, founder and director of BrainFit Studio, which provides mental fitness training.
"The test evaluates key areas of cognitive performance, including quantitative reasoning and visual-spatial processing, among others."
Those who wish to join Mensa can either sit for the Mensa Singapore Admissions Test (MSAT) or take a recognised IQ test administered by a qualified psychologist here, before submitting the results to Mensa for consideration, says a spokesman for Mensa Singapore.
The MSAT is restricted to those who are 14 years old and above, which means that children below the minimum age will have to be tested at a private testing centre of their choice. Mensa membership is for life, adds the spokesman.
"Once a person has been admitted into Mensa, he does not have to re-take any IQ tests in order to continually justify his membership in the society, although he has to keep up with paying of membership fees," he points out.
Currently, there are more than 900 members in Mensa Singapore, a fraction of the 100,000 in about 100 countries all over the world.
The age of the youngest Mensa member here is a mere four years old, with the oldest at 75 years old.
Amid the hype over high IQs, psychologists caution that it is not a be-all and end-all when it comes to measuring intelligence.
Says Ms Cheryl Chia: "IQ testing evaluates only one aspect of cognitive performance and often, evaluations in other aspects may throw light on, and help us gain, more insight into the child's holistic mental performance."
Consultant psychologist at SpecialKids Child Health and Development Clinic, Ms Sharon Lam, says: "For kids of Aidan's age, we also look out for other skills such as social skills, gross and fine motor skills, as well as the ability to play when it comes to evaluating their holistic well-being.
"We're interested in how elaborate the child's pretend play is when he is on his own, as well as whether he can play well with another child."
Children with high IQ sometimes face challenges, especially in the social sphere, she adds.
"Children who are so advanced in their intellectual development may sometimes not relate well with their regular-developing peers, particularly when the child's topic of conversation is too restricted to their interest."
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