Staying Together: A Bidirectional Delay–Coupled Approach to Joint Action

To understand how individuals adapt to and anticipate each other in joint tasks, we employ a bidirectional delay–coupled dynamical system that allows for mutual adaptation and anticipation. In delay–coupled systems, anticipation is achieved when one system compares its own time‐delayed behavior, which implicitly includes past information about the other system’s behavior, with the other system’s instantaneous behavior. Applied to joint music performance, the model allows each system to adapt its behavior to the dynamics of the other. Model predictions of asynchrony between two simultaneously produced musical voices were compared with duet pianists’ behavior; each partner performed one voice while auditory feedback perturbations occurred at unpredictable times during live performance. As the model predicted, when auditory feedback from one musical voice was removed, the asynchrony changed: The pianist’s voice that was removed anticipated (preceded) the actions of their partner. When the auditory feedback returned and both musicians could hear each other, they rapidly returned to baseline levels of asynchrony. To understand how the pianists anticipated each other, their performances were fitted by the model to examine change in model parameters (coupling strength, time‐delay). When auditory feedback for one or both voices was removed, the fits showed the expected decrease in coupling strength and time‐delay between the systems. When feedback about the voice(s) returned, the coupling strength and time‐delay returned to baseline. These findings support the idea that when people perform actions together, they do so as a coupled bidirectional anticipatory system.     

The Struggle to Prevent and Evaluate: Application of Population Attributable Risk and Preventive Fraction to Suicide Prevention Researach

Population attributable risk (PAR) estimates have been used in suicide research to evaluate the impact of psychosocial and socioeconomic risk factors, including affective disorders, traumatic life events, and unemployment. A parallel concept of preventive fraction (PF), allowing for estimation of the impact of protective factors and effectiveness of preventive interventions, is practically unknown in suicidology. The study authors discuss the application of both concepts to suicide research and prevention, and review literature on the subject. Despite several methodological and conceptual limitations, both PAR and PF are valuable instruments to inform development and evaluation of suicide prevention programs.     

Influence of Connectives on Language Comprehension: Eye tracking Evidence for Incremental Interpretation

An eye-tracking experiment investigated whether incremental interpretation applies to interclausal relationships. According to Millis and Just's (1994) delayed-integration hypothesis, interclausal relationships are not computed until the end of the second clause, because the processor needs to have two full propositions before integration can occur. We investigated the processing of causal and diagnostic sentences (Sweetser, 1990; Tversky & Kahneman, 1982) that contained the connective because . Previous research (Traxler, Sanford, Aked, & Moxey, 1997) has demonstrated that readers have greater difficulty processing diagnostic sentences than causal sentences. Our results indicated that difficulty processing diagnostic sentences occurred well before the end of the second clause. Thus comprehenders appear to compute interclausal relationships incrementally.     

Cardiovascular reactivity to psychological stress in aerobically trained versus untrained mild hypertensives and normotensives

Cardiovascular reactivity to video game and mental arithmetic stressors was compared among three groups of men: aerobically trained mild hypertensives, untrained mild hypertensives, and a comparison group of untrained normotensives. Relative to the untrained hypertensives, the trained hypertensives reacted to the video game with marginally smaller systolic blood pressure and diastolic blood pressure, but there were no significant differences between these groups in reactivity during the mental arithmetic task. Comparisons between each hypertensive group and the normotensive group showed that blood pressure (BP) reactivity of normotensives during the video game was generally similar to that of trained hypertensives but smaller than that of untrained hypertensives. These results indicate that aerobic training, which has been found to reduce resting BP in mild hypertensives, may also exert a favorable impact in reducing cardiovascular reactivity of hypertensives during some stressful situations.     

The Construct Validity of Assertion: Contributions of Four Assessment Procedures and Norman's Personality Factors

ABSTRACT The construct validity of assertion was analyzed in three independent correlational studies The convergence of self-reported, laboratory roleplayed, self-observed, and peer-rated measures was examined, as well as their relationship to Norman's peer-rated five personality factors of extraversion, agreeableness, conscientiousness, emotional stability, and culture Twenty-three and 29 undergraduate students participated in Studies 1 and 2, respectively In general, results showed poor convergence among assertiveness measures even when increasing the representativeness and reliability of the role-played laboratory and self-observed measures, as in Study 2 In Study 3, the role-playing test was abandoned and 45 subjects served as peers for one another The results of Study 3 supported the prediction that assertiveness measures showed at least moderate convergence, in addition there were significant relationships between assertiveness and extraversion and between peer-rated assertiveness and agreeableness, conscientiousness, and culture The relative contribution of each assessment procedure to the construct validity of assertion is discussed     

Phonological priming in the lexical decision task: A failure to replicate

Some models of the lexicon predict that recognition of words should produce activation spreading to phonologically related words. Consistent with this prediction, Hillinger (1980) demonstrated priming in a visual lexical decision task for word targets preceded by graphemically similar or graphemically dissimilar primes that rhymed with the target. In Experiment 1, we investigated whether this phonological priming effect occurred automatically or because of subject strategies. Although semantically associated primes produced significant facilitation in Experiment 1, no evidence of phonological priming was obtained. Experiments 2 to 5 were conducted in an attempt to obtain the phonological priming effect. Experiment 5 was a replication of one of Hillinger’s experiments. In none of these experiments was phonological priming observed. These results indicate either that the lexicon is not organized such that spreading activation occurs on the basis of phonological similarity, or that visual lexical decisions are made without phonological mediation.     

A developmental study of the auditory Stroop effect

A pediatric auditory version of the Stroop procedure was developed and administered to 48 normal children from 3 to 6 years of age. Our purpose was to define the developmental course characterizing interaction between auditory and semantic speech dimensions in young children. The procedure was a reaction time (RT) task that required children to respond as quickly and as accurately as possible to words spoken by a male or a female voice. Children were instructed to ignore what was said and to push the "Mommy" button if Mommy was talking or the "Daddy" button if Daddy was talking. Performance was obtained for words with neutral, congruent, and conflicting semantic content. Preschool children manifested processing dependencies that were similar to those observed in adults on the visual Stroop procedure. Conflict between semantic and auditory dimensions significantly increased RT and congruence between the two dimensions significantly decreased RT relative to the neutral condition. The pattern of results indicated that the meaning of words was processed automatically in the normal children. The magnitude of the Stroop effect reflected developmental change with increasing age.     

Self-esteem of adolescent girls as related to weight

The Rosenberg Self-esteem Scale was administered to 550 14- and 16-yr.-old (+/- 6 mo.) girls. Self-esteem scores were categorized by weight and weight by height. Scores on the Quetelet Index for obesity were correlated with self-esteem scores. Mean self-esteem of the low- and middle-weight by height group was significantly higher than the mean of the high-weight by height group. In analyzing weight alone, the self-esteem of the middle-weight group was significantly higher than the self-esteem of the high-weight group. The correlation of the obesity index and self-esteem indicated that as weight increased self-esteem decreased.