Alterations in the Relationship Between Hippocampal Volume and Episodic Memory Performance in Preterm Children

Abstract

This study examines the relationship between episodic memory and hippocampal volume (magnetic resonance imaging [MRI] volumetry) in preterm children with uncomplicated neonatal courses (<34 weeks of gestation, birth weight <2,000 g) and controls (7–11 years). To examine episodic memory performance and retrieval processes, neuropsychological tests and a recognition experiment were used. Although preterm children showed reduced hippocampal volumes relative to controls by 12%, episodic memory accuracy was not reduced. However, only in controls hippocampal volume correlated with some measures of episodic memory. Together, behavioral and MRI results indicate a minor functional specificity of the hippocampus regarding episodic memory functions in preterm children.

ACKNOWLEDGMENTS

The authors thank Martina Becker, Jens Berens, Thorsten Brinkmann, and Michael Kursawe for assistance with data collection. We also thank Axel Mecklinger and Volker Sprondel for helpful comments on an earlier version of this article. We are grateful to the children who participated in this study and their parents for their interest to take part in our research.

This research was supported by the German Research Foundation (KI 1399/1-1).

Notes

¹The test–retest reliabilities of the standardized neuropsychological tests were high: VLMT (r = .68–.87), Rey-Osterrieth Complex Figure (r = .76–.97), and CPM (r = .80–.90).

²Since additional controlling for height, weight, and occipito-frontal head circumference can be regarded as an overcorrection because gender itself includes stature and body weight (Rushton & Ankney, 1996), we only used Gender, SES, and Age as covariates.