Neurophysiological correlates of verbal and nonverbal short-term memory in children: repetition of words and faces

The neurophysiological correlates of verbal and nonverbal memory have been extensively studied in adults, but comparable investigations of children are limited. A memory paradigm that is well established with adults is the repetition task, which finds a positive shift in the ERP waveform in response to repeated items, called the "repetition effect." This is thought to represent the brain's memory trace for previously seen information and is reported predominantly at midline frontal and parietal electrodes. We recorded ERPs in thirteen 11- to 14-year old children during repetition tasks of words and faces. Performance was better and ERP latencies shorter for the word than the face task. Although a repetition effect similar to adults was seen at parietal electrodes with increased positivity to repeated items, increased negativity was observed at frontal electrodes; this suggests that the neural substrates of recognition memory continue to develop beyond 11 to 14 years of age. The demonstration of a repetition effect in children provides a basis for studying the neural correlates of specific childhood memory deficits.