Infants can't distinguish between large and small groups: study

June 19, 2012

Human brains process large and small numbers of objects using two different mechanisms, but infants have not yet developed the ability to make those two processes work together, according to new research from the University of Missouri.

"This research was the first to show the inability of in a single age group to discriminate large and small sets in a single task," said Kristy vanMarle, assistant professor of in the College of Arts and Science. "Understanding how infants develop the ability to represent and compare numbers could be used to improve early education programs."

The MU study found that infants consistently chose the larger of two groups of food items when both sets were larger or smaller than four, just as an adult would. Unlike adults, the infants showed no preference for the larger group when choosing between one large and one small set. The results suggest that at age one infants have not yet integrated the two mental functions: one being the ability to estimate numbers of items at a glance and the other being the ability to visually track small sets of objects.

In vanMarle's study, 10- to 12-month-old infants were presented with two opaque cups. Different numbers of pieces of breakfast cereal were hidden in each cup, while the infants observed, and then the infants were allowed to choose a cup. Four comparisons were tested between different combinations of large and small sets. Infants consistently chose two over one and eight items over four, but chose randomly when asked to compare two versus four and two versus eight.

"Being unable to determine that eight is larger than two would put an organism at a serious disadvantage," vanMarle said. "However, ongoing studies in my lab suggest that the capacity to compare small and large sets seems to develop before age two."

The ability to make about the relative number of objects in a group has old evolutionary roots. Dozens of species, including some fish, and birds have shown the ability to recognize numerical differences in laboratory studies. VanMarle speculated that being unable to compare large and small sets early in infancy may not have been problematic during human evolution because young children probably received most of their food and protection from caregivers. Infants' survival didn't depend on determining which bush had the most berries or how many predators they just saw, she said.

"In the modern world there are educational programs that claim to give children an advantage by teaching them arithmetic at an early age," said vanMarle. "This research suggests that such programs may be ineffective simply because infants are unable to compare some numbers with others."

Explore further: Babies are born with 'intuitive physics' knowledge, researcher says

More information: VanMarle's research was published in the Journal of Experimental Child Psychology.

Related Stories

Babies are born with 'intuitive physics' knowledge, researcher says

January 24, 2012
While it may appear that infants are helpless creatures that only blink, eat, cry and sleep, one University of Missouri researcher says that studies indicate infant brains come equipped with knowledge of "intuitive physics."

Infants taught to maintain ability to distinguish between other-race groups

May 19, 2011
Exposing infants to facial pictures of different races can reduce difficulty in recognising and discriminating between other-race groups later in life, according to a University of Queensland study published today.

Babies understand thought process of others at 10 months old, research finds

November 1, 2011
New research from the University of Missouri indicates that at 10 months, babies start to understand another person's thought process, providing new insights on how humans acquire knowledge and how communication develops.

Recommended for you

Probing how Americans think about mental life

October 20, 2017
When Stanford researchers asked people to think about the sensations and emotions of inanimate or non-human entities, they got a glimpse into how those people think about mental life.

Itsy bitsy spider: Fear of spiders and snakes is deeply embedded in us

October 19, 2017
Snakes and spiders evoke fear and disgust in many people, even in developed countries where hardly anybody comes into contact with them. Until now, there has been debate about whether this aversion is innate or learnt. Scientists ...

Inflamed support cells appear to contribute to some kinds of autism

October 18, 2017
Modeling the interplay between neurons and astrocytes derived from children with Autism Spectrum Disorder (ASD), researchers at University of California San Diego School of Medicine, with colleagues in Brazil, say innate ...

Study suggests psychedelic drugs could reduce criminal behavior

October 18, 2017
Classic psychedelics such as psilocybin (often called magic mushrooms), LSD and mescaline (found in peyote) are associated with a decreased likelihood of antisocial criminal behavior, according to new research from investigators ...

Taking probiotics may reduce postnatal depression

October 18, 2017
Researchers from the University of Auckland and Otago have found evidence that a probiotic given in pregnancy can help prevent or treat symptoms of postnatal depression and anxiety.

Schizophrenia disrupts the brain's entire communication system, researchers say

October 17, 2017
Some 40 years since CT scans first revealed abnormalities in the brains of schizophrenia patients, international scientists say the disorder is a systemic disruption to the brain's entire communication system.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.