Identification of olfactory stimuli as reinforcers in individuals with autism: a preliminary investigation

Preference for six olfactory stimuli was assessed via paired preference assessments with three adults with autism. Using a combination multielement and reversal design, a reinforcer assessment was then conducted to determine the extent to which three (high preference, medium preference, and low preference) of the six olfactory stimuli evaluated in the preference assessment functioned as reinforcers for responding in the context of a sorting task. Relative to baseline, all of the participants exhibited increased responding for access to their high preference olfactory stimulus. The utility of olfactory stimuli as components of behavior intervention plans is discussed. Copyright © 2008 John Wiley & Sons, Ltd.     

Networks of neurons, networks of genes: an integrated view of memory consolidation

Investigations into the mechanisms of memory formation have abided by the central tenet of the consolidation theory-that memory formation occurs in stages which differ in their requirement for protein synthesis. The current most widely accepted hypothesis posits that new memories are encoded as neural activity-induced changes in synaptic efficacy, and stabilization of these changes requires de novo protein synthesis. However, the basic assumptions of this view have been challenged by concerns regarding the specificity of the effects of the protein synthesis inhibitors used to support the claim. Studies on immediate-early genes (IEGs), in particular Arc, provide a distinct and independent perspective on the issue of the requirement of new protein synthesis in synaptic plasticity and memory consolidation. The IEG Arc and its protein are dynamically induced in response to neuronal activity, and are directly involved in synaptic plasticity and memory consolidation. Although we provide extensive data on Arc's properties to address the requirement of genomic and proteomic responses in memory formation, Arc is merely one element in a network of genes that interact in a coordinated fashion to serve memory consolidation. From gene expression and other studies, we propose the view that the stabilization of a memory trace is a continuous and ongoing process, which does not have a discrete endpoint and cannot be reduced to a single deterministic "molecular cascade". Rather, memory traces are maintained within metastable networks, which must integrate and update past traces with new ones. Such an updating process may well recruit and use many of the plasticity mechanisms necessary for the initial encoding of memory.     

Spirituality and Subjective Religiosity among African Americans, Caribbean Blacks and Non-Hispanic Whites

Patterns and correlates of self-perceptions of spirituality and subjective religiosity are examined using data from the National Survey of American Life, a nationally representative study of African Americans, Caribbean Blacks and non-Hispanic Whites. Demographic and denominational correlates of patterns of subjective religiosity and spirituality (i.e., religious only, spiritual only, both religious/spiritual and neither religious/spiritual) are examined. In addition, the study of African Americans and Caribbean Blacks permits the investigation of possible ethnic variation in the meaning and conceptual significance of these constructs within the U.S. Black population. African Americans and Caribbean Blacks are more likely than Non-Hispanic Whites to indicate that they are "both religious and spiritual" and less likely to indicate that they are "spiritual only" or "neither spiritual nor religious." Demographic and denominational differences in the patterns of spirituality and subjective religiosity are also indicated. Study findings are discussed in relation to prior research in this field and noted conceptual and methodological issues deserving further study.     

Emotional Stroop via Internet among individuals with eating disorders

The present study investigated whether Stroop interference in eating disordered individuals for food - and body-related words, as repeatedly found previously using standard emotional Stroop tasks, would also be demonstrated when using an Internet based emotional Stroop task. Participants were anorexic women (n= 13), bulimic women (n= 20), non-clinically eating disordered women nevertheless over-concerned about eating and body appearance (n= 27) and normal control women (n= 31). Bulimic individuals showed Stroop interference for body-related words whereas anorexic individuals showed Stroop interference for food-related words. The present results thus suggest that administration of the emotional Stroop task is possible via the Internet. Furthermore, it is possible that the time consuming response delivery, relative to previous studies, could lead to Stroop interference only for the most emotionally significant information, in turn, differentiating between the core concerns of anorexic and bulimic individuals.     

Trajectories of Social Withdrawal from Middle Childhood to Early Adolescence

Heterogeneity and individual differences in the developmental course of social withdrawal were examined longitudinally in a community sample (N = 392). General Growth Mixture Modeling (GGMM) was used to identify distinct pathways of social withdrawal, differentiate valid subgroup trajectories, and examine factors that predicted change in trajectories within subgroups. Assessments of individual (social withdrawal), interactive (prosocial behavior), relationship (friendship involvement, stability and quality, best friend’s withdrawal and exclusion/victimization) and group- (exclusion/victimization) level characteristics were used to define growth trajectories from the final year of elementary school, across the transition to middle school, and then to the final year of middle school (fifth-to-eighth grades). Three distinct trajectory classes were identified: low stable, increasing, and decreasing. Peer exclusion, prosocial behavior, and mutual friendship involvement differentiated class membership. Friendlessness, friendship instability, and exclusion were significant predictors of social withdrawal for the increasing class, whereas lower levels of peer exclusion predicted a decrease in social withdrawal for the decreasing class.