Toward a model of false recall: Experimental manipulation of encoding context and the collection of verbal reports

The likelihood of false recall in the Deese-Roediger-McDermott (DRM) paradigm was shown to depend on encoding context in two experiments. When fillers had been preselected to decrease the likelihood of encoding the critical lure's semantic features, false recall was virtually eliminated. However, when the same words were presented rearranged in different presentation orders, levels of false recall that were found in earlier DRM studies (Robinson & Roediger, 1997) were replicated. The role of encoding processes in the DRM paradigm was further explored with additional participants completing the experiment while thinking aloud. During encoding of word lists, participants verbalized semantic elaboration of the critical lure while studying the word lists. A path analysis demonstrated that participants' verbalization of critical lures during encoding reliably predicted their level of false recall.     

Projection of the Magnocellular Red Nucleus to the Region of the Accessory Abducens Nucleus in the Rabbit

The projection of the magnocellular red nucleus (RNm) to the region of the accessory abducens nucleus (AABD) was traced in rabbit using the bidirectional tracer wheat germ agglutinin-horseradish peroxidase (WGA-HRP). In one set of animals, recordings of antidromic responses from RNm neurons elicited by electrical stimulation of the rubrospinal tract were used to localize injections of WGA-HRP for orthograde labeling of RNm terminals. In a different set of animals, horseradish peroxidase was injected into the retractor bulbi muscle to retrogradely label motoneurons of the AABD. The positions of RNm fibers and terminals were examined and compared to the locations and distribution of AABD cell bodies and labeled dendrites. Analyses revealed that along the entire rostrocaudal extent of the AABD, RNm efferents terminate primarily lateral to, or in the lateral aspects of, labeled motoneurons. For the rostral AABD, RNm efferents terminate only lateral to the nucleus. Although the terminals are not positioned to contact cell bodies of the AABD, they could overlap with dendrites that extend in the lateral direction. RNm efferents terminate more extensively within the posterior AABD, overlapping within both dendritic and cell body regions of the nucleus. Even in this posterior region, however, RNm efferents were distributed primarily over the lateral half of the nucleus. These data show that RNm can monosynaptically influence the AABD, through primarily its lateral and posterior aspects. Our findings also show that a major target of RNm efferents is the reticular cell population located lateral to the AABD, suggesting that the RNm also may affect AABD motoneuronal output indirectly through its projection to reticular cells.     

Effects of positive youth development programs on school, family, and community systems

A review of efforts at social system change in 526 universal competence-promotion outcome studies indicated that 64% of the interventions attempted some type of microsystemic or mesosystemic change involving schools, families, or community-based organizations in an attempt to foster developmental competencies in children and adolescents. Only 24% of the reports provided quantitative data on the change that occurred in targeted systems. However, studies containing the necessary information produced several mean effect sizes that were statistically significant, and ranged from modest to large in magnitude. These data indicate that attempts to change social systems affecting children and adolescents can be successful. Future work should measure more thoroughly the extent to which the systemic changes that are targeted through intervention are achieved, and investigate how such changes contribute to the development and sustainability of the outcomes that might be demonstrated by participants of competence-promotion programs. The authors wish to thank David Wilson for supplying the macros used to calculate study level effect sizes and Mark Lipsey for supplying the SPSS macros used to weight effect sizes and calculate mean effects across studies. This study was supported in part by a grant from the William T. Grant Foundation (#2212) awarded to the first and last authors.     

The Time Course of Attention: It Is Better Than We Thought

ABSTRACT— What is the time course of attention? Research using rapid-stimulus streams has suggested that it is rather slow: Attention takes half a second to recover from processing one thing before it can process the next. This period is referred to as the attentional blink , and it is thought to reflect a fundamental bottleneck in conscious processing. If this period does exist, such a limitation would have severe consequences in real-life situations in which multiple events may rapidly succeed each other (e.g., in traffic). However, findings that support the attentional blink are at odds with other findings indicating that attention is not reduced, but enhanced, following potentially important occurrences. The article reviews evidence that these opposite effects are actually closely related. The attentional blink is a consequence of selection mechanisms that are not severely limited, but have an adaptive function: They enhance perception in response to relevant information but suppress perception in response to irrelevant information. It means that humans are better geared for real life than was previously thought.