Smoking during pregnancy affects speech-processing ability in newborn infants.
BACKGROUND
Tobacco smoking during pregnancy is known to adversely affect development of the central nervous system in babies of smoking mothers by restricting utero-placental blood flow and the amount of oxygen available to the fetus. Behavioral data associate maternal smoking with lower verbal scores and poorer performance on specific language/auditory tests.


OBJECTIVE
In the current study we examined the effects of maternal smoking during pregnancy on newborns' speech processing ability as measured by event-related potentials (ERPs).


METHODS
High-density ERPs were recorded within 48 hr of birth in healthy newborn infants of smoking (n = 8) and nonsmoking (n = 8) mothers. Participating infants were matched on sex, gestational age, birth weight, Apgar scores, mother's education, and family income. Smoking during pregnancy was determined by parental self-report and medical records. ERPs were recorded in response to six consonant-vowel syllables presented in random order with equal probability.


RESULTS
Brainwaves of babies of nonsmoking mothers were characterized by typical hemisphere asymmetries, with larger amplitudes over the left hemisphere, especially over temporal regions. Further, infants of nonsmokers discriminated among a greater number of syllables whereas the newborns of smokers began the discrimination process at least 150 msec later and differentiated among fewer stimuli.


CONCLUSIONS
Our findings indicate that prenatal exposure to tobacco smoke in otherwise healthy babies is linked with significant changes in brain physiology associated with basic perceptual skills that could place the infant at risk for later developmental problems.
Key
Alexandra P F
AP
Kennedy Center for Research on Human Development and Department of Hearing and Speech Sciences, Vanderbilt University, 21st Avenue South & Edgehill Avenue, Nashville, TN 37203, USA. sasha.key@vanderbilt.edu
Ferguson
Melissa
M
Molfese
Dennis L
DL
Peach
Kelley
K
Lehman
Casey
C
Molfese
Victoria J
VJ
D000328:Adult; D001921:Brain / Q000502:physiology; D002657:Child Development; D005071:Evoked Potentials; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D016555:Matched-Pair Analysis; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012907:Smoking / Q000009:adverse effects*; D013067:Speech Perception