Visual habituation tasks: the role of infant temperament.

This longitudinal study investigated the relation between infant temperament and dropout rate in two visual habituation tasks when infants (N=80) were 6 and 12 months of age. At both age points, infant temperament was assessed with the Infant Behavior Questionnaire Revised (IBQ-R) and infants were presented with the same two habituation tasks that were similar in set-up and procedure but different in content. Consistent with previous German work, a two-factor solution was found at each age point indicating Surgency/Extraversion and Negative Affectivity as underlying temperament dimensions. Dropout rates in the habituation tasks ranged from 21% to 68%. Overall, only few IBQ-R subscales, especially Duration of Orienting, had an impact on dropout rate. This suggests that the relatively high dropout rates reported in infant looking time studies are not systematically related to infant temperament. However, findings also suggest that temperament might have an impact on the likelihood of dropout when a habituation task is conducted at the end of a longer test session.