Poster #6 - Neural Correlates of Perceptual Processing of Spatially Cued Visual Targets in Infancy

• In Event: 2-163 - Poster Session 08
  In Poster Session: PS 08 Section - Attention, Learning, Memory

Integrative Statement

Research indicates that biases in spatial attention have a significant influence on perceptual processing and memory in children and adults (e.g., Astle et al., 2009). Furthermore, a growing body of research findings indicate that spatial cueing can enhance recognition memory in infancy (e.g., Markant & Amso, 2013). However, there is a significant gap in scientific knowledge, and relatively little is known about neural mechanisms associated with visual search in infancy. Addressing this gap is critically important for understanding how infants come to effectively process visual information in naturalistic settings. Past research has shown that the effects of visual attention on perceptual processing change significantly from 3 to 9 months of age (e.g., Reynolds et al., 2013, 2017). These changes may be based on further development of neural systems involved in spatial orienting and attentional control (Reynolds et al., 2013, 2016) that lead to more efficient and functional visual scanning and perceptual processing across the infancy period. Utilizing high-density event-related potentials (ERPs) and a hybrid spatial cueing/recognition memory task, the current study aimed to identify the effects of spatial cueing and covert orienting on neural correlates of infant attention and recognition memory for 4- and 9-month-old infants. We predicted that the older 9-month-olds would demonstrate both facilitation and inhibitory effects of spatial cueing on their perceptual processing of targets, whereas 4-month-olds would only demonstrate facilitation effects due to immaturity of areas of prefrontal cortex involved in higher-order attention and inhibitory control.

Sixteen infants were tested at 4 or 9 months of age. ERP measurements were gathered using a 128 channel EEG net, and participants remained seated on their parent’s lap for the duration of the procedure, which consisted of a spatial cueing task (Posner, 1980). Infants were shown repeated presentations of a dynamic central stimulus paired with a cue shown to the left or right of midline. Following a brief delay (150 ms) the cue and central target were removed and a target appeared for 1500 ms either ipsilateral (valid trials) or contralateral (invalid trails) to the cue location. Using video coding and the electrooculogram for an accurate measure of saccade latency, the ERP was segmented around target fixation onset. The Nc ERP component associated with infant attention and late slow wave (LSW) associated with infant perceptual processing were examined on valid and invalid trials.

Both age groups showed greater amplitude LSW associated with enhanced perceptual processing on valid compared to invalid trials. Interestingly, only 9-month-old infants showed greater amplitude Nc on invalid trials compared to valid trials. Thus, although both age groups showed evidence of enhanced processing of cued targets, only older infants show greater visual attention toward uncued targets. This may indicate that younger infants' neural responsiveness to cued targets was primarily driven by basic spatial orienting processes. In contrast, older infants' neural responsiveness was also influenced by the predictive validity of spatial cues. The greater utilization of spatial cues for older infants may be tied to further development of prefrontal cortex involved in the development of attentional control.

Authors

• William Joseph Chollman, University of Tennessee
  Presenting Author

• Kelly Roth, University of Tennessee Knoxville
  Non-Presenting Author

• Emily Grimes, University of Tennessee
  Non-Presenting Author

• Cait Berosh, University of Tennessee
  Non-Presenting Author

• Mary Alison Bennett, University of Tennessee
  Non-Presenting Author

• Mikhayla Stover, University of Tennessee
  Non-Presenting Author

• Greg D. Reynolds, University of Tennessee
  Non-Presenting Author