Self-injurious behavior: gene-brain-behavior relationships

This paper summarizes a conference held at the National Institute of Child Health and Human Development on December 6-7, 1999, on self-injurious behavior [SIB] in developmental disabilities. Twenty-six of the top researchers in the U.S. from this field representing 13 different disciplines discussed environmental mechanisms, epidemiology, behavioral and pharmacological intervention strategies, neurochemical substrates, genetic syndromes in which SIB is a prominent behavioral phenotype, neurobiological and neurodevelopmental factors affecting SIB in humans as well as a variety of animal models of SIB. Findings over the last decade, especially new discoveries since 1995, were emphasized. SIB is a rapidly growing area of scientific interest to both basic and applied researchers. In many respects it is a model for the study of gene-brain-behavior relationships in developmental disabilities.     

Simulating consciousness in a bilateral neural network: "nuclear" and "fringe" awareness

A technique for the bilateral activation of neural nets that leads to a functional asymmetry of two simulated "cerebral hemispheres" is described. The simulation is designed to perform object recognition, while exhibiting characteristics typical of human consciousness-specifically, the unitary nature of conscious attention, together with a dual awareness corresponding to the "nucleus" and "fringe" described by William James (1890). Sensory neural nets self-organize on the basis of five sensory features. The system is then taught arbitrary symbolic labels for a small number of similar stimuli. Finally, the trained network is exposed to nonverbal stimuli for object recognition, leading to Gaussian activation of the "sensory" maps-with a peak at the location most closely related to the features of the external stimulus. "Verbal" maps are activated most strongly at the labeled location that lies closest to the peak on homologous sensory maps. On the verbal maps activation is characterized by both excitatory and inhibitory Gaussians (a Mexican hat), the parameters of which are determined by the relative locations of the verbal labels. Mutual homotopic inhibition across the "corpus callosum" then produces functional cerebral asymmetries, i.e., complementary activation of homologous "association" and "frontal" maps within a common focus of attention-a nucleus in the left hemisphere and a fringe in the right hemisphere. An object is recognized as corresponding to a known label when the total activation of both hemispheres (nucleus plus fringe) is strongest for that label. The functional dualities of the cerebral hemispheres are discussed in light of the nucleus/fringe asymmetry.     

Dentists' voice control: effects on children's disruptive and affective behavior

Voice control, a punishment technique based on loud commands, has been used widely in pediatric dentistry. This study examined whether (a) loudness is a necessary component of the technique, (b) voice control actually reduces children's disruptive behavior, and (c) after treatment, children's negative affect increases. Subjects were forty 3 1/2- to 7-year-olds who posed potential behavior problems and who were scheduled for cavity restoration. Children were assigned randomly to either loud- or normal-voice groups. Children who were assigned to either group but who were not disruptive formed a nonexperimental control group. Prior to and after treatment, children reported their feelings using the Self-Assessment Mannequin. Disruptive behavior was scored using the Behavior Profile Rating Scale. Results indicated that, following loud, but not normal voice commands, children reduced their disruptive behavior (p less than .004) and self-reported lower arousal (p less than .09) and greater pleasure (p less than .10). Theoretical and practical implications of these findings are discussed.     

Colour inputs to random-dot stereopsis.

Recently it has been claimed by Livingstone and Hubel that, of three anatomically and functionally distinct visual channels (the magnocellular, parvocellular interblob, and blob channels), only the magnocellular channel is involved in the processing of stereoscopic depth. Since the magnocellular system shows little overt colour opponency, the reported loss of the ability to resolve random-dot stereograms defined only by colour contrast seems consistent with this view. However, Julesz observed that reversed-contrast stereograms could be fused if correlated colour information was added. In the present study, 'noise' (non-corresponding) pixels were injected into random-dot stereograms in order to increase fusion time. All six subjects tested were able to achieve stereopsis in less than three minutes when there was only correspondence in colour and not in luminance, and three when luminance contrast was completely reversed. This ability depends on information about the direction of colour contrast, not just the presence of chromatic borders. When luminance and chromatic contrast are defined in terms of signal-to-noise ratios at the photoreceptor mosaic, chromatic information plays at least as important a role in stereopsis as does luminance information, suggesting that the magnocellular channel is not uniquely involved.     

Correlations Between Input and Output Units in Neural Networks

Correlation analyses of recent back-propagation neural networks show that network results are due to imbalances in stimulus input. Conclusions concerning the effects of receptive field size, hemispheric specialization, and other issues of relevance to psychology cannot therefore be drawn until the dominating effects of low-level correlations are removed. Statistical techniques for evaluating the stimulus materials for neural networks are introduced.     

Occupational and Industry Sex Segregation and the Work–Family Interface

This study examines how gender interacts with the extent of occupational and industry sex segregation to affect family-to-work conflict, work-to-family conflict, coworker support, and supportive work-family culture. Using a theoretical framework that highlights the negative ramifications of working in a sex-atypical occupation or industry, we hypothesized that men and women would be impacted differently by the percentage of women in an occupation or industry. The data (N?=?2,810) are from the 2002 National Study of the Changing Workforce (a US sample). Findings suggest that gender interacts with the percentage of women in an industry in significantly predicting coworker support and supportive work–family culture. Gender also interacts with the percentage of women in an occupation in significantly predicting family-to-work conflict.     

Threat of Shock,State Anxiety,and the Holtzman Inkblot Technique

To study the relationship of selected Holtzman Inkblot Technique (HIT) scores and anxiety, Ss were matched on the basis of A-Trait scores on the State-Trait Anxiety Inventory (STAI). The HIT was administered to Ss under neutral and threat of shock conditions. State anxiety was monitored by means of the A-State scale of the STAI. None of the HIT variables reflected changes in A-State due to the experimental conditions. HIT anxiety correlated significantly with STAI A-Trait. Results are discussed in terms of Trait-State Anxiety theory and previous research.     

Testing orofacial abilities of children who stutter: the Movement, Articulation, Mandibular and Sensory awareness (MAMS) assessment procedure

Objective

The purpose of this article is to introduce a new assessment designed to measure the orofacial abilities of children who stutter (CWS), the Movement, Articulation, Mandibular and Sensory Awareness (MAMS) Orofacial Assessment. The new instrument was developed and validated to measure orofacial abilities in a comprehensive manner.

Design

A group of 43 CWS (mean age 13.10 years, S.D. 2.10 years) and a control group of 32 fluent children (mean age 13.4 years, S.D. 2.6 years) were tested with the new tool. It was hypothesized, that (a) the MAMS is a reliable and valid instrument to measure orofacial abilities in CWS, (b) fluent children have better orofacial abilities than CWS and (c) that the therapy outcome of CWS depend on their orofacial abilities.

Results

The MAMS Orofacial Assessment proved to be a valid and reliable instrument to assess orofacial abilities. Compared with their fluent peers, CWS had significantly worse orofacial abilities. CWS with better orofacial abilities had a better prognosis for therapy outcome.

Conclusions

The new instrument is a reliable and valid tool to measure orofacial abilities and MAMS distinguishes CWS and controls. Orofacial abilities are one set of factors that influence therapy outcome for CWS.Educational objectives: The reader will get an overview over of the literature on orofacial abilities in people who stutter and will learn about and be able to (1) describe different characteristics of orofacial abilities, (2) use the MAMS Orofacial Assessment in the diagnostic process for CWS and for research purposes, and (3) interpret the results of the MAMS to use them for therapy planning.