Effects of early tactile stimulation on low birthweight infants : 2-year follow-up study
Three experiments investigated the effects of tactile stimulation on a large sample of infants (N = 115). The pilot experiment used full-term babies (n = 13). It compared the effects of Rice Infant Sensorimotor Stimulation (which involves stroking together with other kinds of stimulation) with various controls. At three months the R.I.S.S. babies had higher scores on the Bayley Developmental Scale. In the main experiment, only stroking (no handling) was used as stimulation for 10-15 minutes, twice daily for 14-21 days employed by the investigator. Birthweight was in the range 760g to 2,200 kg. Three hospitals were used. In the first one, experimental babies (n = 6) gained more weight (by day 21) and were bottle fed and moved to the cot earlier than controls (n = 6). In hospitals 2 and 3, fifty-four babies were treated as coming from the same population (justified by statistical analysis). Some of the findings are that, as compared with controls, treated babies had less weight loss in the first week and higher gain at day 21, and scored higher on sucking and hand grasp. There was some evidence that the gains were greatest if stimulation was started before day 3. At 40 weeks the treated babies scored higher on general measures, but particularly several items of the Dubowitz Assessment Scale. Compared with full-term untreated infants of the same age (n = 10), at 40 weeks the pre-term treated infants had poorer posture, but better auditory orientation and alertness and fewer startles. At 12 months, treated AGA infants scored higher on the Bayley Development Scale (MDI) than untreated AGA infants (blind). Compared with full-term (n = 6) untreated infants of the same age, the preterm AGA untreated and the preterm SGA treated infants had a poorer MDI score (adjusted aged). A final complementary study used a modified stroking technique (n = 20). 'Blind' assessments showed that treated infants had less weight loss in the first week and higher gain at day-21, and scored higher on sucking and hand grasp. They also showed significantly higher scores on posture, leg traction, body movement, rooting, walking, auditory orientation and less irritability. At 6 months, follow-up treated infants scored higher on the Bayley Development Scale (MDI).Concurrent and immediately subsequent reactions to the stimulation showed that treated infants changed their state and showed signs of pleasure (main and complementary studies). The two experiments together provide some evidence that tactile stimulation on its own has beneficial physical, neurological, neuro-behavioural effects.