Phasic and tonic alertness in preterm 5-year-old healthy children

Preterm delivery may interrupt the intrauterine brain development and implies a risk factor for the developing brain. In the long term, most frequently particular forms of attention deficits are described which refer to the basic aspects of attention i.e., arousal or tonic alertness. As this reflects top-down processes, the current study focuses on bottom-up processed phasic alertness in preschool aged preterm children. Additionally, we made a division of response times into decision and movement time to quantify more exactly the contribution of cognitive and motor performance to reaction times. We investigated basic aspects of attention functioning and contrasted phasic and tonic alertness in 31 low-risk healthy preterm (28-36 weeks of gestation) and 22 term children of five to 6 years of age by using a self-designed computerized test. Preterm children exhibited delayed decision and reaction time in the tonic non-cued alertness condition but not in the phasic cued alertness condition compared to term children. Current results suggest that preterm birth, even when clinically relevant symptoms are absent, may have long-term consequences on basic aspects of attention functioning. Results further suggest that preterm children may profit from auditory cues to overcome these deviations, which yield evidence for a clear distinction between impaired top-down and intact bottom-up controlled processes. These findings might provide a promising groundwork for the development of therapeutical interventions and prevention strategies, whose use and impact to support preterm children should be addressed in further investigations.