Vagal modulation of 1-month-old infants to auditory stimuli is associated with self-regulatory behavior

During infancy, cardiac vagal modulation has been associated with
attentional and social engagement behaviors. While studies have
shown that infants display a behavioral repertoire that enables them
to interact with others by being able to regulate themselves in order
to attend to and to discriminate emotional and social cues, vagal modulation
to sensory stimuli and its association with behavioral
outcomes at early ages remains to be addressed. In this study, we
analyzed the cardiac vagal response of 1-month-old infants to two
auditory stimuli intensities and whether vagal response was associated
with social interactive and self-regulatory abilities. Therefore, we
recorded cardiac and respiratory physiological responses in 28 infants
using a Biopac System. Neurobehavioral assessment was performed
using the Neonatal Behavioral Assessment Scale. We observed
increased respiratory sinus arrhythmia (RSA) amplitude to both auditory
stimuli intensities when compared to baseline. No intensity
effect was found for the RSA response. Additionally, we observed
that higher RSA amplitude to both auditory stimuli was positively correlated
with adjusted self-regulatory behaviors, suggesting a
convergence between multiple measures assessing infants’ state regulation.
Results are discussed in light of 1-month-old infants’ auditory
stimuli processing and its implications for regulatory behaviors and
the emergent social-like behaviors.
Foremost, we thank all the families and infants who participated in this study. We would like to thank Pedro Hispano
Hospital, particularly to Dr. J. Lopes dos Santos, for all the kindness throughout the time that we were there
for the data collection process. We thank Maria de Gois-Eanes for all the help and knowledge and Santiago
Galdo-Alvarez for the contributions to this study. Furthermore, we thank Associaç ~ao Viver a Ciencia for the Sim- ^
biontes prize in 2013. This work was supported by Fundaç~ao Bial (grant number 42/08) and financed by Fundaç~ao
para a Ciencia e Tecnologia (FCT) under a PhD grand (reference SFRH/BD/68263/2010).
info:eu-repo/semantics/publishedVersion