How your baby moves can predict her IQ

By Nestor Lopez-Duran PhD

It is fascinating that infant movements can serve as a window into their developing brain. Numerous studies have shown that the quality of infant movements, especially among premature babies, strongly predicts whether the infant will have motor and neurological problems. The basic idea is that in normal development, infants move in very predictable ways, such as deviations from this norm may reflect anomalies in brain development.

Most of the original research reports on infant movements have been focused on motor problems. It makes sense that motor movements would reflect the development of motor regions of the brain. However, some researchers have suggested that infant movements also reflect the integrity of regions of the brain near the motor cortex that are in charge of cognitive and emotional control. Thus, it is sensible to predict that anomalies in infant motor movements may also predict cognitive and social functioning later in life.

In an upcoming issue of the Journal of Child Psychology and Psychiatry, Dr. Phillipa R. Butcher and a team from the University of Groningen report findings from a large longitudinal study of preterm infants. The authors used video tapes made at 11 to 16 weeks post-term in 65 infants born at or before 33 weeks of gestation. These infants were the followed for many years and completed a battery of neurocognitive tests when they were 7 to 11 years of age.

The authors were primarily interested in three types of movements:

1. Fidgeting Movements: These are small, circular movements of varying speed that appear around 6 weeks post-term.

2. Concurrent Movements. At this age, normative concurrent movements included kicking, manipulating clothing, and playing with fingers.

3. Concurrent Postural Patterns. These include for example the ability to hold the head in the midline and manipulating fingers so that the fingers are independent of one another (as opposed to always having the fists closed or open).

The results:

  1. While controlling for maternal IQ and attention problems, an index of motor quality score was a significant predictor of total IQ, Verbal IQ, and Performance IQ when the child was between 7 and 11 years of age.
  2. This association was driven exclusively by the presence and absence of normal and atypical postural patterns. That is, fidgeting movements and concurrent movements did not predict IQ, but it was postural patterns that was the strong predictor of IQ.
  3. There was no association between infant movements and behavior or emotional problems during middle childhood (internalizing and externalizing behavior problems).

The graphic below present a very clear picture of the findings. Note for example that the proportion on children with IQ in the 100 to 115 rage increased linearly as a function of the presence of normal postural patterns during infancy. Among those with less than 2 patterns, none of the children scored in the 100 to 114 rage, while among those with more than 2 postural patterns more than 50% of the children scored in that 100-114 range.

IQ scores as a function of infant postural patterns

The authors then commented on one additional important finding. The association between postural patterns and IQ was not explained by the presence of neurological problems. That is, even among the kids without clear neurological problems (such as Cerebral Palsy), infant movements still predicted IQ scores. These findings have important implications of preventive interventions. For example, the careful examination of infant motor patterns may help us determine which children may be at higher risk for cognitive deficits and could benefit from  intensive early intervention programs.
The Reference: Butcher, P., van Braeckel, K., Bouma, A., Einspieler, C., Stremmelaar, E., & Bos, A. (2009). The quality of preterm infants’ spontaneous movements: an early indicator of intelligence and behaviour at school age Journal of Child Psychology and Psychiatry DOI: 10.1111/j.1469-7610.2009.02066.x