Markers’ influence on the duration discrimination of intermodal intervals

The effects of sensory signal characteristics on the duration discrimination of intermodal intervals was investigated in three experiments. Temporal intervals were marked by either the successive presentation of a visual then auditory signal (VA), or by the successive presentation of an auditory then visual signal (AV). The results indicated that (1) VA intervals are generally easier to discriminate than are AV intervals, but this effect depends on the range of duration studied; (2) AV intervals are perceived as longer than VA intervals for durations ranging from 250 to 750 msec; (3) the intensity of the visual markers for both AV and VA intervals does not affect the discrimination; and (4) the perceived duration of an intermodal interval is influenced by the length of the first and second markers. The results are mainly interpreted in terms of (1) a sensory trace left by visual and auditory signals and (2) the detection of these signals.     

GPOWER: A general power analysis program

GPOWER is a completely interactive, menu-driven program for IBM-compatible and Apple Macintosh personal computers. It performs high-precision statistical power analyses for the most common statistical tests in behavioral research, that is,t tests,F tests, andχ ² tests. GPOWER computes (1) power values for given sample sizes, effect sizes andα levels (post hoc power analyses); (2) sample sizes for given effect sizes,α levels, and power values (a priori power analyses); and (3)α andβ values for given sample sizes, effect sizes, andβ/α ratios (compromise power analyses). The program may be used to display graphically the relation between any two of the relevant variables, and it offers the opportunity to compute the effect size measures from basic parameters defining the alternative hypothesis. This article delineates reasons for the development of GPOWER and describes the program’s capabilities and handling.     

A Quantitative Case Study of Longitudinal Changes in Identity, Intimacy, and Generativity

A quantitative case study of one woman's development was conducted in order to explore psychosocial change in early adulthood. A contentanalytic coding system for identity, intimacy, and generativity themes derived from E. H. Erikson's writing was applied to letters and diaries of the British writer Vera Brittain written when she was 20 to 21 and 30 to 31 years old. Over time, Brittain used more intimacy and generativity themes and fewer identity themes. Even though Brittain used fewer total identity themes in her writing in her early 30s, her use of one identity subcategory—occupational role—increased in frequency, and the way in which she expressed her identity concerns indicated greater certainty about her identity.     

Sensitization and aversive conditioning: Effects on the startle reflex and electrodermal responding

Animal data suggest that shock sensitization as well as aversive learning potentiates the acoustic startle reflex. The present experiment tested, whether this shock sensitization also occurs in human subjects and whether it precedes aversive conditioning. Sixty subjects viewed—prior to conditioning—a series of slides of different emotional contents including the to be conditioned stimuli (CSs). Afterwards, the experimenter attached the shock electrodes and initiated shock exposure. Then, subjects were randomly assigned to view a series of two slides, each for eight acquisition trials in which one slide was followed by a shock. Subsequently, extinction trials (12 for each slide) were administered. During preconditioning, acquisition, and extinction, startle probes occurred unpredictably during and between slide viewing. Preconditioning data replicated previous results by Lang and his associates, showing that the startle response magnitude is directly related to the affective valence induced by the slides. Shock exposure strongly facilitated the startle reflex magnitude. This shock sensitization was absent for the skin conductance response. Course of learning also varied for both response systems. The data suggest that startle reflex potentiation indexes the acquisition of an avoidance disposition, which is preceded by a general sensitization of the protective reflexes. Skin conductance learning follows arousal changes and is modulated by cognitive processes.     

Della sostanza

Inedito (Dal lascito, pp. 30604 – 30620) Con unaIntroduzione di Wilhelm BaumgartnerProbabilmente: Palermo, marzo 1900. Per la datazione, cf. la concordanza di contenuto con la lettera a A. Marty del 28 marzo 1900, in appendice.     

Untersuchungen zur Lehre von der Gestalt

Ohne Zusammenfassung