Brain Development During the Preschool Years

The preschool years represent a time of expansive mental growth, with the initial expression of many psychological abilities that will continue to be refined into young adulthood. Likewise, brain development during this age is characterized by its ??blossoming?? nature, showing some of its most dynamic and elaborative anatomical and physiological changes. In this article, we review human brain development during the preschool years, sampling scientific evidence from a variety of sources. First, we cover neurobiological foundations of early postnatal development, explaining some of the primary mechanisms seen at a larger scale within neuroimaging studies. Next, we review evidence from both structural and functional imaging studies, which now accounts for a large portion of our current understanding of typical brain development. Within anatomical imaging, we focus on studies of developing brain morphology and tissue properties, including diffusivity of white matter fiber tracts. We also present new data on changes during the preschool years in cortical area, thickness, and volume. Physiological brain development is then reviewed, touching on influential results from several different functional imaging and recording modalities in the preschool and early school-age years, including positron emission tomography (PET), electroencephalography (EEG) and event-related potentials (ERP), functional magnetic resonance imaging (fMRI), magnetoencephalography (MEG), and near-infrared spectroscopy (NIRS). Here, more space is devoted to explaining some of the key methodological factors that are required for interpretation. We end with a section on multimodal and multidimensional imaging approaches, which we believe will be critical for increasing our understanding of brain development and its relationship to cognitive and behavioral growth in the preschool years and beyond.     

Parent Participation Within Community Center or In-Home Outreach Delivery Models of the Early Risers Conduct Problems Prevention Program

A variety of predictors of parent participation in prevention programming have been identified in past research, but few studies have investigated how those predictors may vary by implementation context. Patterns of parent participation were examined in the Early Risers Conduct Problems Prevention Program using two family-focused service delivery models: a community center model (Center) and an in-home outreach-based model (Outreach). An ethnically diverse sample of Kindergarten through second grade students (n = 246) displaying elevated levels of aggression were recruited for the study and randomly assigned to either the Center (n = 121) or Outreach (n = 125) models. In both delivery models, participants and their families completed an assortment of baseline measures and received family skills and child skills intervention components and family- and school-based case management. Parents in the Center model demonstrated greater overall participation in family-focused components of the intervention. Parent motivation with parent-focused expectancies for the intervention represented the strongest predictor of parent participation across both delivery models. Family income differentially predicted parent participation across the two models, with low income predicting greater participation in the Center model and lower participation in the Outreach model. A qualitative finding emerged showing that parents receiving parent skills in the Center model via groups preferred to learn skills related to facilitating overall family relationships, whereas parents receiving parent skills via individual Outreach meetings preferred to improve a child’s behavior and emotion skills. Implications are discussed for the design of prevention programming in order to maximize parent participation in high risk populations.     

The effects of prior knowledge on the encoding of episodic contextual details

A positive relationship between prior knowledge and item memory is a consistent finding in the literature. In the present study, we sought to determine whether this relationship extends to episodic details that are present at the time of encoding, namely source memory. Using a novel experimental design, we were able to show both between- and within-subjects effects of prior knowledge on source memory. Specifically, the results revealed that the degree of prior knowledge positively predicted memory for source specifying contextual details. In addition, by including two conditions in which attention was divided either at encoding or retrieval, we were able to show that prior knowledge influences memory by affecting encoding processes. Overall, the data suggest that a priori knowledge within a specific domain allows attentional resources to be allocated toward the encoding of contextual details.     

Affording Emerging Adulthood: Parental Financial Assistance of their College-Aged Children

The purpose of this study was to examine parents’ attitudes about and patterns of providing financial assistance to their children during college, and how varying levels of parental financial support were related to children’s beliefs (e.g., perceptions of adulthood), behaviors (e.g., work hours, drinking, and drug use), and identity development. The sample consisted of 402 undergraduate students (62% women) recruited from four college sites across the United States (M age = 19.89), and one of their parents (310 mothers and 92 fathers). Using cluster analysis, results suggested four distinct approaches to parental financial involvement and found that emerging adults’ beliefs, behaviors, and identity development differed as a function of parents’ cluster membership. Discussion focuses on implications for emerging adult children whose parents endorse varying levels of financial involvement.     

Adult mice maintained on a high-fat diet exhibit object location memory deficits and reduced hippocampal SIRT1 gene expression

Mounting evidence has established that diet-induced obesity (DIO) is associated with deficits in hippocampus-dependent memory. The bulk of research studies dealing with this topic have utilized rats fed a high-fat diet as an experimental model. To date, there has been a paucity of research studies that have established whether the memory deficits exhibited in DIO rats can be recapitulated in mice. Moreover, the majority of experiments that have evaluated memory performance in rodent models of DIO have utilized memory tests that are essentially aversive in nature (i.e., Morris water maze). The current study sought to fill an empirical void by determining if mice maintained on a high-fat diet exhibit deficits in two non-aversive memory paradigms: novel object recognition (NOR) and object location memory (OLM). Here we report that mice fed a high-fat diet over 23 weeks exhibit intact NOR, albeit a marked impairment in hippocampus-dependent OLM. We also determined the existence of corresponding aberrations in gene expression within the hippocampus of DIO mice. DIO mice exhibited significant reductions in both SIRT1 and PP1 mRNA within the hippocampus. Our data suggest that mice maintained on a high-fat diet present with impaired hippocampus-dependent spatial memory and a corresponding alteration in the expression of genes that have been implicated in memory consolidation.     

Memory modulation in the classroom: selective enhancement of college examination performance by arousal induced after lecture

Laboratory studies examining moderate physiological or emotional arousal induced after learning indicate that it enhances memory consolidation. Yet, no studies have yet examined this effect in an applied context. As such, arousal was induced after a college lecture and its selective effects were examined on later exam performance. Participants were divided into two groups who either watched a neutral video clip (n=66) or an arousing video clip (n=70) after lecture in a psychology course. The final examination occurred two weeks after the experimental manipulation. Only performance on the group of final exam items that covered material from the manipulated lecture were significantly different between groups. Other metrics, such as the midterm examination and the total final examination score, did not differ between groups. The results indicate that post-lecture arousal selectively increased the later retrieval of lecture material, despite the availability of the material for study before and after the manipulation. The results reinforce the role of post-learning arousal on memory consolidation processes, expanding the literature to include a real-world learning context.     

The Bull's-Eye Values Survey: A Psychometric Evaluation

Two studies were conducted to develop and evaluate an instrument intended to identify and measure personal values, values attainment, and persistence in the face of barriers. Study 1 describes a content validity approach to the construction and preliminary validation of the Bull's Eye Values Survey (BEVS), using a sample of institutionalized patients suffering from epilepsy. Study 2 investigated the psychometric properties of the BEVS with a sample of Swedish university students. Results suggest that the BEVS is sensitive to treatment effects and can differentiate between clients who receive values-based interventions and those who do not. The BEVS subscales and total score appear to measure an independent dimension of psychological functioning that is negatively correlated with measures of depression, anxiety, and stress, and positively correlated with a measure of psychological flexibility. The BEVS also exhibits acceptable temporal stability and internal consistency. The study provides preliminary support for the BEVS as both a research and clinical tool for measuring values, values-action discrepancies, and barriers to value-based living.     

Happiness is not Well-Being

This paper attempts to explain the conceptual connections between happiness and well-being. It first distinguishes episodic happiness from happiness in the personal attribute sense. It then evaluates two recent proposals about the connection between happiness and well-being: (1) the idea that episodic happiness and well-being both have the same fundamental determinants, so that a person is well-off to a particular degree in virtue of the fact that they are happy to that degree, and (2) the idea that happiness in the personal attribute sense can serve as a “proxy” for well-being, i.e., that a person’s degree of deep or robust happiness approximates their degree of well-being. It is argued that happiness in both these senses is conceptually, metaphysically, and empirically distinct from well-being. A new analysis of welfare, well-being as agential flourishing, can explain welfare’s real connection to happiness in both the episodic and personal attribute senses. It predicts that such happiness is only directly beneficial when it is valued, when it is a form of valuing, or when it underwrites (i.e., serves as the causal basis for) the disposition to realize one’s values. It is therefore a necessary—but not sufficient—condition for especially high levels of well-being. This analysis of welfare integrates many insights from the eudaimonic tradition of welfare and happiness research in psychology, and also addresses common criticisms of these eudaimonic models.     

Does syntax contribute to the function of duets in a parrot, Amazona auropalliata?

Complex acoustic signals in many animal species are characterized by a syntax that governs how different notes are combined, but the importance of syntax to the communicative function of signals is not well understood. Mated pairs of yellow-naped amazons, Amazona auropalliata, produce coordinated vocal duets that are used for territory maintenance and defense. These duets follow rules that specify the ordering of notes within duets, such as a strict alternation of sex-specific notes and a defined progression of note types through each duet. These syntactical rules may function to define sex-specific roles, improve coordination, and allow individuals to combine calls into meaningful sequences. As a first step toward understanding the functional significance of syntax, we conducted two separate audio playback experiments in which we presented nesting pairs with normal duets and duets with broken syntax (i.e., one of the syntactic rules was broken). In Experiment One, we reversed the order of female and male notes within note pairs while retaining the typical progression of note types through a duet. In Experiment Two we reversed the order of note types across a whole duet while retaining the typical female-male ordering within note pairs. We hypothesized that duets with broken syntax would be less-effective signals than duets with normal syntax and predicted that pairs would respond less to broken syntax than to normal duets. Contrary to predictions, we did not observe differences in response between treatments for any variables except latency to approach the speaker. After we combined data across experiments post hoc, we observed longer latencies to approach the speakers after playbacks of broken syntax duets, suggesting that pairs could differentiate between playbacks. These responses suggest that breaking one rule of duet syntax at a time does not result in detectable loss of signal efficacy in the context of territorial intrusions.