The Evoked K-Complex in Infants: Effects of Prenatal Nicotine Exposure (2015)

Undergraduates: Erin King, Karen Grewen, Aysenil Belger, Alana Campbell

Faculty Advisor: Aysenil Belger
Department: Psychology & Neuroscience

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Smoking cigarettes during pregnancy is detrimental to the health of the unborn child, yet 15% of expectant mothers smoke. Prenatal nicotine exposure correlates with sensory processing deficits and increased risk of developing disorders of attention (Horst et al., 2012; Heath & Picciotto, 2009). The K-complex is produced by the GABAergic networks in the brain, and these networks have been implicated in attention. The K-complex can first be seen in infants around 4 months of age (AASM Manual for Scoring Sleep, 2007) and indicates the degree of sensory processing (Andreassi, 2007). In this study, brain activity was recorded during a paired-click paradigm to elicit auditory K-complexes in 4-month-old infants exposed to nicotine prenatally and healthy controls during a nap. Stage 2 sleep was then identified, the epoch of the EEG recording around the K-complex was analyzed, and the amplitude and amount of delta band (1-4Hz) power in the K-complex were computed. The prenatal nicotine exposure group shows a smaller amplitude and less delta power than the control group. This may suggest that infants exposed to nicotine do not appropriately gate out sensory information and fail to proceed into deeper sleep necessary for typical development. It is possible that the K-complex can be used as a biomarker for the development of attentional deficiencies in the future.