Virtual reality cue reactivity assessment in cigarette smokers.

Drug craving has purportedly been linked to relapse and to substance use. For over two decades, cue reactivity has been a viable method to assess craving and physiological reactions to drug stimuli. However, traditional cue reactivity has faced the following limitations: austere situations or stimuli, lack of complex cues, lack of standardization, and limited generalization outside of the lab setting. In order to improve cue methodologies, a virtual reality (VR) nicotine cue reactivity assessment system (VR-NCRAS) was developed and tested in a controlled experimental trial. Ten nicotine dependent smokers were exposed to VR smoking cues and VR neutral cues in a standardized, timed, computer controlled experiment. Subjective craving and physiological responses were recorded and compared across VR-NCRAS stimuli. Subjective cigarette craving increased significantly and corresponding physiological reactivity was observed in response to VR smoking cues. VR neutral cues did not result in subjective or physiological changes consistent with craving. Implications of these findings on substance abuse research and treatment are discussed.     

The relationship between non-symbolic multiplication and division in childhood

Children without formal education in addition and subtraction are able to perform multi-step operations over an approximate number of objects. Further, their performance improves when solving approximate (but not exact) addition and subtraction problems that allow for inversion as a shortcut (e.g., a?+?b???b?=?a). The current study examines children's ability to perform multi-step operations, and the potential for an inversion benefit, for the operations of approximate, non-symbolic multiplication and division. Children were trained to compute a multiplication and division scaling factor (*2 or /2, *4 or /4), and were then tested on problems that combined two of these factors in a way that either allowed for an inversion shortcut (e.g., 8*4/4) or did not (e.g., 8*4/2). Children's performance was significantly better than chance for all scaling factors during training, and they successfully computed the outcomes of the multi-step testing problems. They did not exhibit a performance benefit for problems with the a*b/b structure, suggesting that they did not draw upon inversion reasoning as a logical shortcut to help them solve the multi-step test problems.     

Adults’ number-line estimation strategies: Evidence from eye movements

Although the development of number-line estimation ability is well documented, little is known of the processes underlying successful estimators’ mappings of numerical information onto spatial representations during these tasks. We tracked adults’ eye movements during a number-line estimation task to investigate the processes underlying number-to-space translation, with three main results. First, eye movements were strongly related to the target number’s location, and early processing measures directly predicted later estimation performance. Second, fixations and estimates were influenced by the size of the first number presented, indicating that adults calibrate their estimates online. Third, adults’ number-line estimates demonstrated patterns of error consistent with the predictions of psychophysical models of proportion estimation, and eye movement data predicted the specific error patterns we observed. These results support proportion-based accounts of number-line estimation and suggest that adults’ translation of numerical information into spatial representations is a rapid, online process.     

Young children's haptic exploratory procedures

Adults vary their haptic exploratory behavior reliably with variation both in the sensory input and in the task goals. Little is known about the development of these connections between perceptual goals and exploratory behaviors. A total of 36 children ages 3, 4, and 5 years and 20 adults completed a haptic intramodal match-to-sample task. Participants were instructed to feel the shape, texture, rigidity, or weight of a sample object and then were asked to find which of three test objects matched the sample on that specific property. Hand movements were examined to determine whether children produced the same exploratory procedures while gathering perceptual information about each property as adults who searched for the same kind of information. Children demonstrated that they had good haptic abilities in two ways: They matched the sample objects on the specified perceptual dimension at near ceiling levels, and they produced the same hand movement patterns to find the same properties as adults.     

Development of a Biomedical Program of Research in the Blackfeet Community: Challenges and Rewards

American Indian (AI) communities have high levels of stress and trauma and are disproportionately affected by numerous preventable diseases. Here, we describe an academic–community partnership based on a collaboration between Blackfeet Community College students and faculty in Psychology and Immunology at Montana State University (MSU). The collaboration, which has spanned over 5 years, was sparked by community interest in the relationship between stress and disease on the Blackfeet reservation. Specifically, community members wanted to understand how the experience of psychological stress and trauma may affect disease risk in their community and identify factors that promote resilience. In doing so, they hoped to identify pathways through which health could be improved for individual community members. Here, we discuss all stages of the collaborative process, including development of measures and methods and themes of research projects, challenges for community members and non‐indigenous collaborators, future directions for research, and the lessons learned. Finally, we note the ways in which this partnership and experience has advanced the science of community engagement in tribal communities, with the hope that our experiences will positively affect future collaborations between indigenous community members and non‐indigenous scientists.     

Measuring lexical diversity in children who stutter: application of vocd

There is growing but equivocal evidence that the language abilities of young children who stutter (CWS) may be depressed when compared to those of their fluent peers. In particular, the lexical skills of CWS have variously been reported to be weaker or stronger than comparison children in a number of recent studies. One source for such disagreement may be the measures used to compute lexical characteristics of these children's spoken conversations. In this study, we examined the concurrent validity of two measures of lexical diversity in spontaneous language samples, Type-Token Ratio (TTR) and the newly developed utility vocd (Malvern & Richards, 1997), using a standard test of expressive vocabulary as the comparison measure. Findings indicated that vocd values ("D") correlated well with standardized measures of expressive vocabulary, while TTR values did not. In addition, both the standardized measure and vocd revealed significantly poorer expressive lexical skills of CWS, whereas TTR analyses did not evidence this difference. Results are discussed in relation to the relative strength of vocd over TTR as a method for describing lexical characteristics of the spontaneous language samples of this population. EDUCATIONAL OBJECTIVES: The reader will learn about and be able to (1) identify several common measures of conversational vocabulary and the strengths and weaknesses of each, and (2) compare the performance of the young CWS in this study to their normally fluent peers in terms of vocabulary performance on both formal and conversational measures of vocabulary.     

Community Violence as It Affects Child Development: Issues of Definition

The state of the art of definition of community violence as it relates to child development was examined in terms of the definitions used in 23 empirical studies. In all cases community violence was defined in terms of what were assumed to be measurements obtained as linear combinations of a priori numerical weighting of responses to questions--asked either of a child or of the parent of a child--about experiencing and/or witnessing and/or hearing about instances of violence. Thus, the definitions can be seen to represent the perspectives of 2 kinds of observers--the child or the child's parent--and 3 levels of closeness to violence--experiencing, witnessing, or hearing about violence. Combining these perspectives and levels, the following 8 different definitions could be seen to be used in the practice of 1 or more of the 23 empirical studies: Child Self-Report (perception) of either (1) experiencing, or (2) witnessing, or (3) experiencing and witnessing, and hearing about violence; or Parent Report (perception) of the Child (4) experiencing, or (5) witnessing, or (6) experiencing and witnessing and hearing about violence, or (7) = (1) + (4), or (8) = (3) + (6). In almost all the examples of research definitions it was assumed implicitly and without test of the assumption that different violent events were interchangeable, and usually it was assumed (again without test) that the magnitudes of different violence events were equal. Usually, an unstated theory of stress appeared to guide the measurement definition, but in one study definitions were developed and tested in terms of a clearly-stated theory of learning. It was concluded that definition of community violence is a measurement problem; that very likely it is multidimensional; that it could be more nearly solved if better attention were given to specifying it in terms of theory that can be put to test and by attending to basic assumptions and principles of measurement.     

Adolescents' reasoning about exclusion from social groups

Ninth- and 11th-grade students (N = 379) were surveyed regarding their evaluations of excluding someone from a social group solely on the basis of his or her social reference group membership. Individuals evaluated exclusion in ambiguous and nonambiguous situations. Judgments and reasoning about exclusion were compared with judgments and reasoning about a more prototypically moral situation (denial of resources). Overall, participants evaluated exclusion as less wrong than denial of resources and used fewer moral and more conventional reasons to justify their judgments. Participants relied more on their group knowledge or stereotypes in evaluating ambiguous situations and more on their personal knowledge in evaluating nonambiguous situations. Age- and gender-related differences in evaluations, reasoning, and use of stereotypes were also found.