Eyeblink Conditioning as a biomarker for children’s success on spatial reorientation tests

• In Event: 2-083 - How do navigational skills develop in typical and atypical populations?

Integrative Statement

After losing a sense of position in the environment, animals use a variety of cues, such as salient landmarks and the geometric shape of their environment, to reorient themselves in and navigate their surroundings. Spatial reorientation develops slowly across early childhood such that, compared to school-aged children, pre-school children perform poorly on large-scale spatial tasks. It has been suggested that the hippocampus underlies this developmental change given that the hippocampus is involved in spatial navigation and reorientation both in animals and human adults. However, although we know a fair amount about when spatial abilities develop, little research has attempted to address what role the developing neurobiological system plays in explaining development of these spatial abilities. Furthermore, most studies of large-scale spatial ability have primarily focused on age-related changes, ignoring the role of individual differences in performance. Characterizing the underlying neurobiology associated with the development of individual differences in spatial reorientation is difficult due to the paucity of age-appropriate methods that can be used to examine brain function in young children. Here, we propose the use of a non-invasive technique, Pavlovian trace eyeblink conditioning (EBC), as an indirect measure for hippocampal function that can be used with young children. Trace EBC is hippocampal-dependent and is relatively easy to use with young pediatric populations, making it an ideal measure to understand individual differences in hippocampal function and its association with spatial reorientation. To address this, the present study examined whether variability in hippocampal function via trace EBC is involved in individual differences in certain spatial reorientation strategies used by young children. Fifty 3- to 6-year-old children (M=4.89 years; SD=1.11) completed a spatial reorientation test, a trace EBC paradigm, and a non-hippocampal-dependent Pattern Comparison Processing Speed (PCPS) test. Conditioned responses (%CR) during EBC were analyzed in relation to children’s spatial reorientation strategies, which included using geometric cues and combining geometric and landmark cues to guide their search. Figure 1 demonstrates that there is variability in performance at each age in both Geometric Strategy Score (i.e., percentage of correct plus diagonal corners chosen; Figure 1A) and Combined Strategy Score (i.e., percentage of correct corners chosen; Figure 1B). Results revealed that EBC performance significantly predicted children’s geometric strategy use (B=.223; p=.014; Figure 2A), but not their combined strategy use (B=.062; p=.607; Figure 2B) or PCPS abilities (B=-.006; p=.866), independent of age. Findings indicate that hippocampal function as measured by trace EBC performance plays an important role primarily in the use of geometric spatial reorientation strategies. Furthermore, the current results point to EBC as a simple, novel biomarker of young children’s hippocampal-dependent spatial reorientation strategies.

Authors

• Vanessa Vieites, Florida International University
  Presenting Author

• Shannon M Pruden, Florida International University
  Non-Presenting Author

• Anna Shusterman, Wesleyan University
  Non-Presenting Author

• Bethany Reeb-Sutherland, Florida International University
  Non-Presenting Author