Infants Oscillatory Frequencies change during Free-Play.

Social interactions are known to be an essential component of infant development. For this reason, exploring functional neural activity while infants are engaged in social interactions will enable a better understanding of the infant social brain. This in turn, will enable the beginning of disentangling the neural basis of social and non-social interactions as well as the influence that maternal engagement has on infant brain function. Maternal sensitivity serves as a model for socio-emotional development during infancy, which poses the question: do interactions between parents and their offspring present altered electrophysiological responses in comparison to the general population if said parents are at risk of mental health disorders? The current research aimed to observe the oscillatory activity of 6-month-old infants during spontaneous free-play interactions with their mother. A 5-minute unconstrained free-play session was recorded between infant-mother dyads with EEG recordings taken from the 6-month-old infants (n = 64). During the recording, social and non-social behaviours were coded and EEG assessed with these epochs. Results showed an increase in oscillatory activity both when an infant played independently or interacted with their mother and oscillatory power was greatest in the alpha and theta bands. In the present 6-month-old cohort, no hemispheric power differences were observed as oscillatory power in the corresponding neural regions (i.e. left and right temporal regions) appeared to mirror each other. Instead, temporal estimates were larger and different from all other regions, whilst the frontal and parietal regions bihemispherically displayed similar estimates, which were larger than those observed centrally, but smaller than those displayed in the temporal locations. The interactions observed between the behavioural events and frequency bands demonstrated a significant reduction in power comparative to the power observed in the gamma band during the baseline event. The present research sought to explore the obstacle of artificial play paradigms for neuroscience research, whereby researchers question how much these paradigms relate to reality. The present manuscript will discuss the strengths and limitations of taking an unconstrained free-play approach.