Will infants search when ‘no toy’ is hidden? A study of implicit assumptions about the development of object permanence

In the Piagetian tradition, presence or absence of a sense of object permanence is inferred from whether an infant does or does not search when an object is occluded. This line of reasoning entails an implicit assumption, i.e. an infant will not search if no object is seen to disappear. This assumption was evaluated in three studies of 9- and 12-month-old infants' responses to ‘hiding’ toy and ‘no toy’ in different orders in one and two positions. The infants did not search for ‘no toy’ when it preceded toy hiding, but they did search for ‘no toy’ when it followed ‘toy’ under some conditions.     

Dimensional shift and the transfer of attention

Dimensional shift was examined by generating gradients of two-dimensional stimulus generalization for intradimensional and extradimensional transfer of attention. Undergraduates discriminated between lines varying in length and orientation. Stimulus values were relevant on one dimension and irrelevant on another. For intradimensional transfer, the Phase 2 transfer task involved discriminating between new values on the dimension that was relevant in Phase 1. For extradimensional transfer, Phase 2 involved discriminating between new values on the dimension that was irrelevant in Phase 1. Extradimensional transfer was learned in twice the number of trials that were required for intradimensional transfer. In Experiment 1, generalization gradients obtained at different stages of Phase 2 training showed that control by the relevant dimension was maintained throughout the intradimensional transfer. In the extradimensional transfer, however, control by the previously relevant dimension was gradually lost before control by the new relevant dimension was acquired. Experiment 2 showed that the advantage of intradimensional over extradimensional transfer could not be attributed to cue-specific stimulus generalization. Experiment 3 showed that in extradimensional transfer the irrelevant dimension in Phase 1 retarded acquisition of control by the new relevant dimension in Phase 2. Experiment 4 showed that the irrelevant dimension masked control by the relevant dimension in the generalization test, but verified the conclusion from Experiment 3 that learned irrelevance contributed to the intradimensional-extra-dimensional transfer difference.     

Awareness Effects of a Youth Suicide Prevention Media Campaign in Louisiana

Research on the efficacy of mediated suicide awareness campaigns is limited. The impacts of a state‐wide media campaign on call volumes to a national hotline were analyzed to determine if the advertisements have raised awareness of the hotline. We use a quasi‐experimental design to compare call volumes from ZIP codes where and when the campaign is active with those where and when the campaign is not active. Multilevel model estimates suggest that the campaign appears to have significantly and substantially increased calls to the hotline. Results from this study add evidence to the growing public health literature that suggests that mediated campaigns can be an effective tool for raising audience awareness.