Brainy babies

“Anecdotal evidence suggests that stimulating the human fetus in the womb can markedly improve its outcome and development, somehow enhancing intelligence,” says Professor Peter Hepper of Queen’s University Belfast. Some expectant mothers swear by Mozart, while others have opted for commercially produced prenatal stimulation kits - Walkman-sized devices that play sounds to the developing fetus.

The postulated benefits are certainly enticing: one kit promises “longer new-born attention span, better sleep patterns, accelerated development, expanded cognitive powers, enhanced social awareness and extraordinary language abilities”. But are they real? With Showcase funding, Professor Hepper is testing whether use of the devices has any effect and, if so, whether the kits themselves are responsible: “Is it because the baby has been stimulated? Or is it a very keen mother trying to do the best for her baby? Maybe it’s not the stimulation per se but the type of mother.”

The theory behind claims for ‘fetal learning’ is that stimulation activates brain cells and prevents their atrophy – which may be as high as 75 to 90 per cent after birth. Nerve ‘stimulation’ might also increase dendritic branching, thereby increasing connectivity and enhancing fetal brain development. There is little direct evidence of a beneficial effect, says Professor Hepper, but he is keen to explore the issue further. “There may be great benefits where appropriate stimulation has effect, for example, in cases of abnormal development or treatment of premature babies.”

In his pilot study at the Royal Maternity Hospital Belfast, Professor Hepper aims to recruit pregnant women at their 18- to 20-week ultrasound scan. Each mother who volunteers will be allocated, randomly, to one of three groups of approximately 50 women. The first group will receive no additional sound stimulation. The second group will wear a fetal stimulation unit for 30 minutes daily; rhythmic heartbeat-type sounds emanate from the device with increasing complexity during the pregnancy. In the third group, the mothers-to-be will be played random selections of music. “This grouping avoids any potential problems of ‘self-selection’ and the lack of randomness identified from previous studies, where mothers in the prenatal stimulation group were assigned on the basis of having bought the stimulation kits.”

To assess the effects of the treatments, the expectant mothers will undergo tests at their regular hospital antenatal sessions at 28, 32 and 38 weeks. Fetal growth and activity will be monitored and, after birth, data will be collected on the baby’s delivery and from numerous commonly used baby and infant development tests. The babies will be followed until their first birthday.

“The key element is to see whether the prenatal stimulation group perform any better on any of the tasks compared to the ‘no sound’ control group or the sound group,” says Professor Hepper. “We want to show whether stimulation has an effect per se. If so, the stimulation group will outperform the other groups. But, if it’s a question of increased auditory stimulation not specific to the prenatal stimulation programme, both the stimulation and sound groups will perform better than the control group. It may be the general increased exposure to sound in the pregnancy that is having the effect and not necessarily the stimulation.”

The outcome of this pilot project will fuel future studies. For example, if the results from the stimulation and sound groups are similar, further research will be needed to disentangle the influence of the sound stimulus and maternal attention. And it would be important to determine whether the effect is a permanent one, or is simply a temporary enhancement during infancy.

Professor Hepper’s project is part of a larger body of work based on the idea that early stimulation – even before birth – can have profound effects on brain development. “Interestingly, we are now coming to realise that brain development is, to a certain extent, experience dependent,” says Professor Hepper. “For example, there is clear evidence that shows a need for exposure to vertical lines in order to develop corresponding brain receptors to recognise and decode them.”

If stimulation does turn out to have a positive effect, it could prove a valuable treatment in conditions such as Down’s syndrome. But there are additional ethical issues to consider. It would potentially put yet more pressure on pregnant mothers, and would add to what Professor Hepper calls “the philosophical arguments surrounding ‘super-babies’”.

See also

• Showcase awards: Funding details
• A bug’s death: Article describing (Showcase funded research) on iron uptake in pathogenic bacteria
• Gas attack: Article describing (Showcase funded research) research to develop a device to safeguard divers
• Thinking big: Article describing (Showcase funded research) on the development of biodegradable polymers for use in drug delivery

External links

• Queen’s University Belfast: Research interests of Peter Hepper

Further reading

Doherty N N, Hepper, P G (2000). Habituation in fetuses of diabetic mothers. Early Human Development, 59: 85–93.

Sneddon H, Hadden R, Hepper P G (1998). Chemosensory learning in the chicken embryo. Physiology and Behavior 64: 133–139.

Hepper P G, Shannon E A, Dornan J C (1997). Sex differences in fetal mouth movements. Lancet 350: 1820.

Hepper P G (1995). The behaviour of the fetus as an indicator of neural functioning. In Fetal Development. A psychobiological perspective. Lecanuet J-P, Fifer W, Krasnegor N, Smotherman W (Eds). Lawrence Erlbaum:Hillsdale, NJ, 405–417.

Hepper P G (1996). The fetus during pregnancy. In The Psychology of Reproduction. Volume 2. Conception, pregnancy and birth. Niven C A, Walker A (Eds). Butterworth Heinemann: Oxford. 57–73.

Hepper P G (1996). Fetal behaviour: why so sceptical? Ultrasound in Obstetrics and Gynecology 8: 145–148.

Hepper P G (1996). Fetal memory: Does it exist? What does it do? Acta Paediatrica Suppl. 416: 16–20.

Hepper P G, Leader L R (1996). Fetal habituation. Fetal and Maternal Medicine Review 8: 109–123.

Hepper P G, McCartney G R, Shannon E A (1998). Lateralized behaviour in first trimester human fetuses. Neuropsychologia 36: 531–534.

McCartney G R, Hepper P G (1999). Development of lateralized behaviour in the human fetus from 12–27 weeks’ gestation. Developmental Medicine and Child Neurology 41: 83–86.

Hepper P G, Cleland J (1999). Developmental aspects of kin recognition. Genetica 104: 199–205.