Poster #13 - A neurodevelopmental approach to understanding the role of sleep in visual working memory

• In Event: 1-005 - Poster Session 01
  In Poster Session: PS 01 Section - Attention, Learning, Memory

Integrative Statement

Lack of sleep has long been known to negatively affect cognition. In infants and children sleep is thought to facilitate neural plasticity through synaptic downscaling, facilitating memory and learning. Past research has found that later sleep is associated with poorer cognition in early years, and that the loss of just one hour of sleep can affect cognition throughout the day. Visual Working Memory (VWM) is a core cognitive system with a highly limited capacity, and has been found to be predictive of general fluid intelligence and correlates highly with many aspects of cognition. The present study aims to examine the role that sleep patterns play in the development of cognition in 6-month-old infants, with particular reference to the VWM network. We predicted that infants who had fewer wake episodes during their sleep period would demonstrate activation throughout the VWM network, and similarly would perform better at the experimental task.
The present study utilised a preferential looking task, where infants saw two side-by-side flickering displays, composed of an array of coloured squares, and on one display, one of the squares would change colour with each presentation. Infants who demonstrated systematic looking to the changing side were able to encode the non-changing display in their VWM. Infant looking was measured with an eye-tracker sampling at 500Hz. Throughout the task, optical neuroimaging data were collected from bilateral frontal, temporal, parietal, and occipital cortex, using fNIRS. Infant sleep measures were recorded using an actigraphy device, attached to a wrist or ankle, which can be used to measure movement and temperature. Sleep data were collected over a period spanning at least 5 days from each infant.
The data suggests that infants’ sleep patterns affected their performance in the preferential looking task, with wake episodes during each sleep period found to be predictive of performance in the task. The fNIRS data showed activation in the frontal, temporal and parietal regions, key areas in the VWM network, demonstrating an association between disrupted sleep measures and VWM in the early years. These findings were cross-referenced against other sleep scoring measures, further highlighting the beneficial nature of efficient sleep in early cognitive development.
The findings of the present study suggest a critical role for sleep in early infant development, particularly in the early development of the VWM network. The findings of this optical imaging study support the results of previous behavioural experiments which have found that sleep fragmentation affects executive function, and may lead to poorer cognition over time. These results suggest possible effectiveness of a sleep-based intervention in early childhood. The wider implications of these results for early cognitive development are also discussed.

Authors

• Samuel Forbes, University of East Anglia
  Presenting Author

• Lourdes Marielle Delgado Reyes, School of Psychology, University of East Anglia
  Non-Presenting Author

• Joe R Cassidy, University of East Anglia
  Non-Presenting Author

• John Spencer, University of East Anglia
  Non-Presenting Author