Morphological development of the human prefrontal cortex (PFC) proceeds well into the 2nd decade of life. However, evidence regarding the developmental time course of 'frontal' functions is limited. A wealth of evidence implicates the dorsolateral PFC and its connections in spatial working memory functions. In this study, we examined whether age-related changes occur in spatial WOrking memory abilities during the 2nd decade of life. Three hundred and eight male participants, approximately 14 years old, and 170 male participants, approximately 20 years old, performed a computerized spatial delayed response task. The task was similar in design to tasks previously used in neurophysiological studies of the PFC in nonhuman primates. Results indicate that spatial working memory abilities improve significantly from age 14 to 20. Similar results were obtained using a dual task design in which participants were required to read words during the delay period of the spatial working memory task.
Bibliographical noteFunding Information:
This research was supported by a grant from the National Institute of Drug Abuse (DA6103). We kindly thank Monica Luciana, PhD for providing us with the software for her computerized spatial delay task.