Fluctuations and phase symmetry in coordinated rhythmic movements

Pendular, clocking movements typify mammalian terrestrial locomotion. They can be investigated with a procedure in which people swing hand-held pendulums at the wrists, comfortably and rhythmically. Pendular, clocking behavior was examined for in-phase and out-of-phase coordinations. The periodic timing and powering of rhythmic movements in the comfort state follow from different laws (Kugler & Turvey, 1986). One law guides the assembling of the reference frame for "clocking." Another law guides the assembling of the muscular, escapement processes determining the cycle energy. Wing and Kristofferson's (1973) method for parsing periodic-timing variance into independent "clock" and "motor" sources was applied. Mean periodicity was unaffected by phase. "Clock" fluctuations, however, were larger out of phase than in phase. "Motor" fluctuations were indifferent to phase but reflected the departures of individual wrist-pendulum systems from their preferred periods. It appears that an intended phase relation is realized as a constraint on "clock" states. These states are more stable under the in-phase constraint than under the out-of-phase constraint.     

The locus of intersensory facilitation of reaction time

When an imperative visual stimulus is paired with an auditory (accessory) stimulus, RT is generally faster than with the imperative stimulus alone. Three experiments using additive-factors logic tested an energy-summation view of the accessory, where effects are due to increased rate of information build-up in sensory stages, and a preparation-enhancement view which holds that the accessory serves an alerting function. Experiment 1 found no interaction between the accessory presence and (visual) stimulus brightness, suggesting no role of the accessory in stimulus identification. Experiment 2 found no interaction between accessory presence and spatial S-R compatibility, arguing that the accessory operated in stage(s) other than response selection. Experiment 3 produced an interaction between the accessory and movement complexity, arguing for accessory effects in a response-programming stage. The data generally favored preparation-enhancement, and offered no support for an energy-summation view.     

Prevalence of personality disorders among bulimics,nonbulimic binge eaters,and normal controls

We examined the comorbidity of bulimia and personality pathology among college women. Subjects included women (n=23) meeting DSM-III-R criteria for bulimia nervosa (bulimics), women (n=23) who reported binge eating but did not fulfill the criteria for bulimia nervosa (binge eaters), and women (n=23) who did not binge eat (normals). The subjects completed an assessment battery consisting of the Personality Disorders Examination and the SCID as well as the Beck Depression Inventory, the Rosenberg Self-Esteem Index, and measures of impulsivity and self-defeating tendencies. Fourteen of 23 bulimics (61%) met criterion for a personality disorder using DSM-III-R Axis II criteria. In comparison, 3 of 23 (13%) binge eaters and 1 of 23 (4%) normal subjects received an Axis II diagnosis. Borderline and self-defeating diagnoses were the predominant personality disorders in 96% of the bulimics exhibiting clinically significant personality pathology. Bulimics also exhibited significantly more depression, impulsivity, and self-defeating behavior and lower self-esteem than binge eaters and normals. The findings are discussed within a conceptual framework that posits an interaction between personality pathology and restrained eating.     

The effects of narrative context on French verbal inflections: A developmental perspective

This experiment examines how narrative context affects French subjects' selection of past imperfective (imparfait) vs. perfective inflections with different predicate types. Adults and 10-year-old children were asked to inflect verbs presented in their written infinitive form in two conditions: (a) in isolated sentences; (b) embedded in the beginning, middle, or end of narratives. Regardless of conditions, the adults rarely used theimparfait with punctual resultative predicates. In both conditions, the frequency ofimparfait was high with durative predicates, particularly with aresultative ones, but it varied with position in the narratives, being highest at the beginning and lowest at the end. Although the children also used the imparfait frequently with durative predicates, they overgeneralized it to punctual resultative ones, regardless of conditions and of positions. These results show that adult uses of the imperfective/perfective distinction are determined by both predicate properties and grounding in narrative context. The children are less sensitive to some predicate properties than the adults and they do not differentiate imperfective/perfective aspect consistently as a function of discourse context.     

Operate your own World-Wide Web server

Although many researchers wishing to use the World-Wide Web for academic purposes rely on centralized Web services, they should be aware that it is neither expensive nor difficult to operate their own server. Doing so provides research-related benefits such as complete control over their host name and documents provided, the guaranteed ability to execute common gateway interface and server-side include programs, immediate access to their collected data, and the ability to better control who participates in their experiments. This paper surveys Web-server software features likely to be of interest to psychologists and conceptually summarizes their operation and use. The basic steps required to set up a Web server on popular microcomputers are reviewed, and security issues concerning Web-server operation are discussed. An accompanying resource Web page can assist users in setting up their own servers.     

The specific action of different personality risk factors on cancer of the breast, cervix, corpus uteri and other types of cancer: A prospective investigation

We report the results of a prospective study of a random sample of 1353 elderly but healthy men and women who were followed up for a period of 10 yr, when mortality and cause of death were ascertained. Overall results have been reported elsewhere for mortality from cancer, coronary heart disease and other causes; here we are concerned with the personality factors predicting breast cancer, cervical cancer, cancer of the corpus uteri specifically, as well as other types of cancer in women. Ten specific hypotheses were tested, using specially constructed questionnaires for the purpose, and for most of these statistically significant support was obtained. The results justify belief that specific types of cancer may be related to specific stress/personality factors.