Genetic studies of stuttering in a founder population

Genome-wide linkage and association analyses were conducted to identify genetic determinants of stuttering in a founder population in which 48 individuals affected with stuttering are connected in a single 232-person genealogy. A novel approach was devised to account for all necessary relationships to enable multipoint linkage analysis. Regions with nominal evidence for linkage were found on chromosomes 3 (P=0.013, 208.8 centiMorgans (cM)), 13 (P=0.012, 52.6 cM), and 15 (P=0.02, 100 cM). Regions with nominal evidence for association with stuttering that overlapped with a linkage signal are located on chromosomes 3 (P=0.0047, 195 cM), 9 (P=0.0067, 46.5 cM), and 13 (P=0.0055, 52.6 cM). We also conducted the first meta-analysis for stuttering using results from linkage studies in the Hutterites and The Illinois International Genetics of Stuttering Project and identified regions with nominal evidence for linkage on chromosomes 2 (P=0.013, 180-195 cM) and 5 (P=0.0051, 105-120 cM; P=0.015, 120-135 cM). None of the linkage signals detected in the Hutterite sample alone, or in the meta-analysis, meet genome-wide criteria for significance, although some of the stronger signals overlap linkage mapping signals previously reported for other speech and language disorders. EDUCATIONAL OBJECTIVES: After reading this article, the reader will be able to: (1) summarize information about the background of common disorders and methodology of genetic studies; (2) evaluate the role of genetics in stuttering; (3) discuss the value of using founder populations in genetic studies; (4) articulate the importance of combining several studies in a meta-analysis; (5) discuss the overlap of genetic signals identified in stuttering with other speech and language disorders.     

Social interaction patterns of geriatric home and community residents

Thirty elderly nursing home residents and ten community residing older adults were observed in group settings. Their behavior was assessed for dependent personal maintenance, independent personal maintenance, and appropriate and inappropriate behaviors. Responses by staff and peers to these behaviors were classified as positive, negative, or ignore. The frequency of occurrence of these behaviors as well as the relationship of resident to peer or staff behaviors were analyzed. Results indicate that community-residing elders' behaviors differ from nursing home residents' in quantity rather than quality of interactions. There was a lower frequency of behaviors in the nursing home residents. Though older adults respond differentially to various behaviors of other nursing home residents, staff responses were consistent regardless of residents' behavior. These results suggest that geriatric home residents' behavior can be characterized as withdrawn rather than dependent.     

Case study: Controlling self-injurious escape behaviors

The present study investigated the effects of a treatment program on the self-injurious behaviors of a 12-year-old autistic male. Initial observations indicated that these behaviors functioned primarily as escape responses to terminate performance demands. For 1 year the subject received general compliance training with the frequency of demands being systematically increased through consecutive treatment weeks. The subject's self-injurious behaviors were no longer reinforced by his escaping from demands nor did they receive social attention. Compliance to demands and appropriate behaviors in general were positively reinforced. The treatment produced substantial reductions in the rates of self-injurious behaviors and increased compliance. Additionally, the intensity of the subject's self-injurious behaviors decreased over the course of treatment. The present study suggests that the treatment approach is a reliable means of not only reducing self-injurious behaviors but also expanding performance repertoires.     

Political Psychology as a Lens for Viewing Traumatic Events

A burgeoning area of scientific inquiry uses psychological perspectives to understand traumatic events. This research has led to the identification of psychological symptoms and disorders frequently experienced in response to traumatic events. Many of the events having traumatic effects on large numbers of persons are of interest to political psychologists. Such events include the Holocaust, war, terrorism, captivity, torture, political migration, living as a political refugee, and assassination. Some interpersonal forms of trauma, such as rape and incest, also may be viewed with a political perspective. Although a number of studies have examined psychological consequences of political events, this area of inquiry is rarely explicitly considered within the domain of political psychology. Adopting an explicitly political psychology perspective on traumatic events may enrich our interdisciplinary understanding of these events and inform the design and evaluation of intervention programs to reduce psychological distress resulting from these events.     

Inhibition by Reinforcement: Effects of Reinforcer Magnitude and Timeout on Fixed-Ratio Pausing

The Psychological Record - Rats were trained on fixed-ratio schedules with different reinforcer magnitudes (concentrations of sweetened milk), using procedures in which responding was allowed to...     

Detection and identification thresholds for consonant-vowel syllables

Detection and identification thresholds were obtained for 6- and 10-year-old normal children and normal adults using five-formant synthesized consonant-vowel ([baHdflrfea]) stimuli. Sixyear-old children were found to have poorer detection than adults, just as they do for pure tones. For the identification task, the slopes of the performance-intensity functions were more shallow for 6-year-old children than for 10-year-olds and adults. Consequently, compared with 10-yearolds and adults, 6-year-old listeners require a greater increase in stimulus intensity above detection threshold to identify these stimuli at a high performance level. The influence of acoustic characteristics of the stimuli on all listeners is also discussed.