Dorsal and ventral striatal protein synthesis inhibition affect reinforcer valuation but not the consolidation of instrumental learning

The evidence for a role of the striatum in the acquisition of uncued instrumental responding is ambiguous. It has been shown that post-session infusions of anisomycin into the core of the nucleus accumbens (NAcc) impaired instrumental acquisition, but pre-training lesions of the NAcc suggest that it is not necessary. Recently, we demonstrated that the infusion of anisomycin into the anterior cingulate cortex impaired instrumental acquisition indirectly through a taste aversion. Thus, we hypothesized that post-session anisomycin infusions into the NAcc affected instrumental acquisition through an effect on reinforcer valuation. For the dorsal striatum, both post-session infusions of anisomycin and pre-training lesion studies suggest that neither the dorsolateral nor the dorsomedial striatum is necessary for the acquisition of instrumental responding. However, it has not been attempted to block plasticity in both regions concurrently, and we hypothesized that both regions independently contribute to acquisition through goal-directed and habitual learning. In the current experiments, we first replicated the effect of unprotected post-session anisomycin infusions into the NAcc on instrumental acquisition. Subsequently, we investigated the effect of protein synthesis inhibition in the NAcc and dorsomedial and dorsolateral striatum concurrently on instrumental acquisition, critically controlling for effects on reinforcer valuation. The anisomycin infusions induced an aversive state, but did not affect instrumental acquisition.     

Environment and Physical Activity Dynamics: The Role of Residential Self-selection

OBJECTIVES: Within the socio-ecologic framework, diet and physical activity are influenced by individual, interpersonal, organizational, community, and public policy factors. A basic principle underlying this framework is that environments can influence an individual's behavior. However, in the vast majority of cross-sectional and even the few longitudinal studies of this relationship, the question of whether individuals select their area of residence based on physical activity-related amenities is ignored. In this paper, we address a critical methodological issue: self-selection of residential location, which is generally not accounted for, and can significantly compromise research on the relationship between environmental factors and physical activity behaviors. METHOD: We define and discuss the problem of residential self-selection in the study of neighborhood influences on health and health behavior, review methods used to control for residential self-selection in the literature, and present our strategy for addressing this potentially important source of bias. CONCLUSION: Existing research has built our understanding of residential self-selection bias, but important gaps remain. Our strategy uses data from a longitudinal cohort study linked to contemporaneous environmental measures to create a multi-equation model system to simultaneously estimate residential choice, environmental influences on physical activity, and downstream health outcomes such as obesity and clinical cardiovascular disease risk factor measures.     

Directed forgetting of faces: the role of response criterion

In two experiments, we examined recognition for faces following item method directed forgetting. During testing, participants reported whether the face was a new face or, if they thought it was a studied face, they identified the instruction paired with the face during study. In both experiments, the proportion of new faces falsely recognized and classified as forget faces exceeded those falsely recognized and classified as remember faces. Despite the use of different response criteria during testing, participants showed greater discrimination accuracy when identifying remember faces than when identifying forget faces. Taken together, these data patterns indicate that participants employed a strength-based criterion when responding. Specifically, participants responding to new faces were more likely to classify those faces as forget faces from study rather than as remember faces from study.     

Does augmented feedback from pedometers increase adults' walking behavior?

This study investigated whether feedback from pedometers motivated adults to increase their walking behavior. Participants (n =26) were enrolled in one of two 8-wk. "Walking for Fitness" classes. The study used a crossover design, such that Group 1 wore pedometers for the first 3 weeks (Feedback Condition) and sealed "disguised" pedometers for the last 3 weeks (No-feedback Condition). The order of feedback was reversed for Group 2. Analysis indicated that (a) neither group increased their walking behavior significantly over time and, (b) interactions between groups were not significant at Week 3 or 6, indicating that groups did not respond differently to feedback from the pedometers. If a motivational effect from pedometers exists, it may be small, dissipate before 3 wk., only work in combination with goal setting, or only motivate certain types of individuals.     

Modification of magnitude estimations in thermotactile perception during self-generated and externally generated movements

Fourteen participants felt a 'cold' stimulus move across a fingertip. When movement was self-controlled, the stimulus was reported as feeling less 'cold' than when movement was externally generated.     

Assessment of infant cry: acoustic cry analysis and parental perception

Infant crying signals distress to potential caretakers who can alleviate the aversive conditions that gave rise to the cry. The cry signal results from coordination among several brain regions that control respiration and vocal cord vibration from which the cry sounds are produced. Previous work has shown a relationship between acoustic characteristics of the cry and diagnoses related to neurological damage, SIDS, prematurity, medical conditions, and substance exposure during pregnancy. Thus, assessment of infant cry provides a window into the neurological and medical status of the infant. Assessment of infant cry is brief and noninvasive and requires recording equipment and a standardized stimulus to elicit a pain cry. The typical protocol involves 30 seconds of crying from a single application of the stimulus. The recorded cry is submitted to an automated computer analysis system that digitizes the cry and either presents a digital spectrogram of the cry or calculates measures of cry characteristics. The most common interpretation of cry measures is based on deviations from typical cry characteristics. Another approach evaluates the pattern across cry characteristics suggesting arousal or under-arousal or difficult temperament. Infants with abnormal cries should be referred for a full neurological evaluation. The second function of crying--to elicit caretaking--involves parent perception of the infant's needs. Typically, parents are sensitive to deviations in cry characteristics, but their perception can be altered by factors in themselves (e.g., depression) or in the context (e.g., culture). The potential for cry assessment is largely untapped. Infant crying and parental response is the first language of the new dyadic relationship. Deviations in the signal and/or misunderstanding the message can compromise infant care, parental effectiveness, and undermine the budding relationship. (c) 2005 Wiley-Liss, Inc. MRDD Research Reviews 2005;11:83-93.     

Promoting and protecting youth mental health through evidence-based prevention and treatment

For decades, empirically tested youth interventions have prevented dysfunction by addressing risk and ameliorated dysfunction through treatment. The authors propose linking prevention and treatment within an integrated model. The model suggests a research agenda: Identify effective programs for a broadened array of problems and disorders, examine ethnicity and culture in relation to intervention adoption and impact, clarify conditions under which programs do and do not work, identify change mechanisms that account for effects, test interventions in real-world contexts, and make tested interventions accessible and effective in community and practice settings. Connecting the science and practice of prevention and treatment will be good for science, for practice, and for children, adolescents, and their families.     

Brain network interactions in auditory, visual and linguistic processing

In the paper, we discuss the importance of network interactions between brain regions in mediating performance of sensorimotor and cognitive tasks, including those associated with language processing. Functional neuroimaging, especially PET and fMRI, provide data that are obtained essentially simultaneously from much of the brain, and thus are ideal for enabling one to assess interregional functional interactions. Two ways to use these types of data to assess network interactions are presented. First, using PET, we demonstrate that anterior and posterior perisylvian language areas have stronger functional connectivity during spontaneous narrative production than during other less linguistically demanding production tasks. Second, we show how one can use large-scale neural network modeling to relate neural activity to the hemodynamically-based data generated by fMRI and PET. We review two versions of a model of object processing - one for visual and one for auditory objects. The regions comprising the models include primary and secondary sensory cortex, association cortex in the temporal lobe, and prefrontal cortex. Each model incorporates specific assumptions about how neurons in each of these areas function, and how neurons in the different areas are interconnected with each other. Each model is able to perform a delayed match-to-sample task for simple objects (simple shapes for the visual model; tonal contours for the auditory model). We find that the simulated electrical activities in each region are similar to those observed in nonhuman primates performing analogous tasks, and the absolute values of the simulated integrated synaptic activity in each brain region match human fMRI/PET data. Thus, this type of modeling provides a way to understand the neural bases for the sensorimotor and cognitive tasks of interest.