Fetal habituation correlates with functional brain development.

In this study, we divided 26 fetuses at 32-37 weeks of gestation into three groups using combined criteria of gestational age and behavioral indicators. We investigated fetal habituation to vibroacoustic stimulation (VAS). Fetuses showed habituation from at least 32 weeks of gestation. Furthermore, fetuses less developed from behavioral standpoint took significantly more trials to achieve habituation than developed fetuses even in the same gestational age. Taken together with these data, it was proved that there was a relationship between aspects of behavioral development and habituation.