Effects of Exogenous and Endogenous Distracters on Immediate and Long-Term Recall in Toddlers Wallace E. Dixon, Jr., Hannah G. Lawman, Elizabeth B. H. Johnson, Sarah May, Leslie A. Patton, Allison K. Lowe, and Courtney M. Snyder Department of Psychology East Tennessee State University We explored the role that exogenous and endogenous competitors for atten- tion play in infants’ abilities to encode and retain information over a 6-month period. Sixty-six children visited the laboratory at 15 months, and 32 returned for a second visit at 21 months. Children observed models of conventional- relation and enabling-relation action sequences. Half the children were distracted by a ‘‘Mister Monkey’’ mechanical toy during the conventional-rela- tion sequence, while the other half was distracted during the enabling- relation sequence. The Early Childhood Behavior Questionnaire indexed endogenous factors at both ages. Immediate postmodel production of target actions indexed encoding efficiency, and 6-month production of target actions indexed long-term recall. The exogenous distracter impacted encoding effi- ciency (i.e., immediate recall), but not long-term recall. Endogenous factors (i.e., temperament) were primarily associated with long-term recall. Of special interest was our finding that endogenous factors, especially surgency, moder- ated the effect of the exogenous distracter. It appears that when learning con- ventional-relation sequences in the presence of exogenous distracters, surgency mobilizes attentional resources toward the learning objective; however, when learning enabling-relation sequences under the same conditions, surgency either boosts the saliency of the distracters or boosts children’s susceptibility to them. Correspondence should be sent to Wallace E. Dixon, Jr., Department of Psychology, East Tennessee State University, PO Box 70649, Johnson City, TN, 37604. E-mail: dixonw@ etsu.edu Infancy, 1–33, 2011 Copyright Ó International Society on Infant Studies (ISIS) ISSN: 1525-0008 print / 1532-7078 online DOI: 10.1111/j.1532-7078.2011.00090.x