Selection and inhibition in infancy: evidence from the spatial negative priming paradigm

We used a spatial negative priming (SNP) paradigm to examine visual selective attention in infants and adults using eye movements as the motor selection measure. In SNP, when a previously ignored location becomes the target to be selected, responses to it are impaired, providing a measure of inhibitory selection. Each trial consisted of a prime and a probe, separated by 67, 200, or 550 ms interstimulus intervals (ISIs). In the prime, a target was accompanied by a distractor. In the probe, the target appeared either in the location formerly occupied by the distractor (ignored repetition) or in another location (control). Adults exhibited the SNP effect in all three ISI conditions, producing slower saccade latencies on ignored repetition versus control trials. The SNP effect obtained for infants only under 550 and 200 ms ISI conditions. These results suggest that important developments in visual selection are rooted in emerging inhibitory mechanisms.     

Audio-visual speech perception is special

In face-to-face conversation speech is perceived by ear and eye. We studied the prerequisites of audio-visual speech perception by using perceptually ambiguous sine wave replicas of natural speech as auditory stimuli. When the subjects were not aware that the auditory stimuli were speech, they showed only negligible integration of auditory and visual stimuli. When the same subjects learned to perceive the same auditory stimuli as speech, they integrated the auditory and visual stimuli in a similar manner as natural speech. These results demonstrate the existence of a multisensory speech-specific mode of perception.     

Heart Follows Head: Influencing Violence-related Attitudes in the Classroom

We examined whether an undergraduate course on violence would influence students’ violence-related attitudes and beliefs. Students (N=145) completed the Violence-Related Attitudes and Beliefs Scale (V-RABS) at the beginning (Time 1) and end (Time 2) of the semester-long course. As expected, support for the death penalty, punishment, and catharsis decreased significantly, as did belief in an association between mental illness and violence. Acceptance of environmental influences on violent behavior increased significantly, although belief in biological influences did not change. Support for violence prevention efforts was high at both Times 1 and 2, and did not change significantly. Consistent with previous research, the results of this study confirm that college curricula may influence students’ attitudes and beliefs in addition to imparting knowledge.     

Choosing or Being Chosen by Aggressive–Disruptive Peers: Do They Contribute to Children's Externalizing and Internalizing Problems?

The goal of this study was to investigate the extent to which aggressive-disruptive peers contribute to the development of externalizing and internalizing problems in children, while controlling for children's own behavior. We examined 2 sets of peers: (1) those that the child nominated as friends, and (2) those that nominated the child as a friend. The participants were 236 boys and girls attending 3rd to 5th grade at the beginning of the study, who were followed over a period of 2 years. Results showed that choosing more aggressive peers on the nomination procedure was associated with more externalizing problems and self-reported depressive symptomatology over time. On the other hand, being liked by more aggressive children generally was not associated with elevated externalizing or internalizing problems.     

Local influence analysis of nonlinear structural equation models

By regarding the latent random vectors as hypothetical missing data and based on the conditional expectation of the complete-data log-likelihood function in the EM algorithm, we investigate assessment of local influence of various perturbation schemes in a nonlinear structural equation model. The basic building blocks of local influence analysis are computed via observations of the latent variables generated by the Metropolis-Hastings algorithm, while the diagnostic measures are obtained via the conformal normal curvature. Seven perturbation schemes, including some perturbation schemes on latent vectors, are investigated. The proposed procedure is illustrated by a simulation study and a real example. Acknowledgment: This research is fully supported by a grant (CUHK 4243/02H) from the Research Grant Council of the Hong Kong Special Administration Region. The authors are indebted to ICPSR and the relevant funding agency for allowing use of their data, and to the Editor and reviewers for their valuable comments for improving the paper.     

Internal versus external attention in social anxiety: an investigation using a novel paradigm

Several cognitive models propose that social anxiety is associated with increased self-focused attention. Indirect evidence for this hypothesis has been provided by questionnaire studies, and by cognitive psychology paradigms that have demonstrated reduced processing of external information during feared social-evaluative situations. However, no studies have simultaneously measured on-line attention to internal and external events. A probe detection task that aimed to measure the balance of attention between internal and external stimuli was developed. High and low socially anxious individuals were instructed to detect two probes. The external probe was superimposed on pictures of faces (happy, neutral, angry) or household objects that were presented on a VDU. The 'internal' probe was a pulse to the finger which participants were led to believe represented significant changes in their physiology. Compared to low speech anxious individuals, high speech anxious individuals showed an internal attentional bias, that was specific to conditions of social-evaluative threat.     

Anxiety and selective attention in obsessive-compulsive disorder

Recently, there has been increasing evidence for information-processing deficits in individuals with obsessive-compulsive disorder (OCD). While impairments in selective attention have been identified to be central to the symptomatology of OCD, the role that situational anxiety plays in attentional processes has not been fully explored. Previous research findings were limited to tasks containing anxiety-relevant materials, only permitting for the evaluation of the impact of anxiety on simultaneous cognitive processing. Furthermore, it has not yet been determined whether the impact of anxiety is limited to selective attention or is indicative of a more general cognitive impairment. This study was designed to examine the role that situational anxiety plays in selective attention impairments. OCD participants and controls were presented with an anxiety producing statement and a neutral statement, followed by the Stroop Task. Results indicated that situational anxiety plays a significant role in the performance of tasks that require selective attention in OCD. A significant deterioration was detected in performance on selective attention tasks for the OCD participants after confronting anxiety-provoking scenarios, as compared to neutral scenarios. Anxiety did not impair performance on simple reading tasks. Possible explanations are discussed.     

Selective influence through conditional independence

Let each of several (generally interdependent) random vectors, taken separately, be influenced by a particular set of external factors. Under what kind of the joint dependence of these vectors on the union of these factor sets can one say that each vector is selectively influenced by “its own” factor set? The answer proposed and elaborated in this paper is: One can say this if and only if one can find a factor-independent random vector given whose value the vectors in question are conditionally independent, with their conditional distributions selectively influenced by the corresponding factor sets. Equivalently, the random vectors should be representable as deterministic functions of “their” factor sets and of some mutually independent and factor-independent random variables, some of which may be shared by several of the functions.     

Peer pressure against prejudice: A high school field experiment examining social network change

Individuals often conform to the intergroup attitudes and behaviors modeled by their peers in a given situation. To what extent does peer influence on intergroup prejudice 1) diffuse across a social network of peers and 2) affect attitudes and behavior across time? Student leaders (“Peer Trainers”) were trained to confront expressions of intergroup prejudice in five randomly assigned high schools across a period of five months; students recruited to be Peer Trainers in five control schools waited to be trained. Independent surveys of Peer Trainers' social networks reveal that treatment Peer Trainers were significantly more likely than control Trainers to be nominated by peers as students who confront prejudice. Treatment Peer Trainers' tolerant behavior spread to close friends and to acquaintances in their social network; their attitudes spread inconsistently, and only to close friends. Studying peer influence within social networks can improve understanding of social influence, prejudice reduction, and social change.