SIMSTAT: Bootstrap computer simulation and statistical program for IBM personal computers

SIMSTAT is a computer program that provides bootstrap confidence intervals and estimates distribution parameters for 27 univariate and bivariate statistics. Because it permits variation of the bootstrap sample size, it is a convenient tool for research planning, allowing comparison of power estimates and estimator precision for various estimators and/or sample sizes. SIMSTAT also is a useful tool for studying the robustness of various statistics on real-world data and may be helpful in teaching statistical principles.     

Linguistic and other psychological aspects of paroxysmal aphasia

A case of paroxysmal aphasia is reported. Aphasic spells occurred, in this patient, without modification in consciousness and without involvement of behaviors others than those related to oral and written speech and language. Longer spells successively recapitulated the clinical pictures of global, Wernicke's, conduction, and amnestic aphasia. Besides aphasiological evaluations, neurological, psychometrical, electroencephalographical, and CT-scan documents were obtained. The discussion bears on four main points: the linguistic characteristics of paroxysmal aphasia as compared to those of aphasias of other etiologies; Pierre Marie's oneness doctrine of aphasia; the mutual relationships of language and thought (in aphasia); the affective experience lived by one with severe aphasia, with special reference to the notion of anosognosia.     

What is matched in direct matching? Intention attribution modulates motor priming

Converging evidence has shown that action observation and execution are tightly linked. The observation of an action directly activates an equivalent internal motor representation in the observer (direct matching). However, whether direct matching is primarily driven by basic perceptual features of the observed movement or is influenced by more abstract interpretative processes is an open question. A series of behavioral experiments tested whether direct matching, as measured by motor priming, can be modulated by inferred action goals and attributed intentions. Experiment 1 tested whether observing an unsuccessful attempt to execute an action is sufficient to produce a motor-priming effect. Experiment 2 tested alternative perceptual explanations for the observed findings. Experiment 3 investigated whether the attribution of intention modulates motor priming by comparing motor-priming effects during observation of intended and unintended movements. Experiment 4 tested whether participants' interpretation of the movement as triggered by an external source or the actor's intention modulates the motor-priming effect by a pure instructional manipulation. Our findings support a model in which direct matching can be top-down modulated by the observer's interpretation of the observed movement as intended or not.     

The factor structure of the Beck Depression Inventory-II: an evaluation

The Beck Depression Inventory-II (BDI-II) is a frequently used scale for measuring depressive severity. BDI-II data (404 clinical; 695 nonclinical adults) were analyzed by means of confirmatory factor analysis to test whether the factor structure model with a somatic-affective and cognitive component of depression, formulated by Beck and colleagues, has a good fit. We also evaluated 10 alternative models. The fit of Beck's model was not good for all criteria. Three of the alternative models had a better fit in both samples, but none of these met all criteria for good fit. Of the alternatives with a better fit, we selected the only model with unidimensional subscales, which assesses a somatic, affective, and cognitive dimension. For this model, which we recommend, as well as for Beck' original model, a good fitting structure containing 15 and 16 items was developed with an item-deletion algorithm.     

Brazilian version of the Protocole Montréal d'Evaluation de la Communication (Protocole MEC): normative and reliability data

The lack of standardized instruments to evaluate communication disorders related to the right hemisphere was verified. A new evaluation tool was developed: Protocole Montréal d'Evaluation de la Communication--Protocole MEC, adapted to Brazilian Portuguese--Bateria Montreal de Avalia??o da Comunica??o--Bateria MAC (Montreal Evaluation of Communication Battery). The purpose was to present stratified normative data by age and educational level, and to verify the reliability parameters of the MEC Battery. 300 individuals, between the ages of 19 and 75 years, and levels of formal education between 2 and 35 years, participated in this study. They were divided equally into six normative groups, according to three age categories (young adults, intermediary age, and seniors) and two educational levels (low and high). Two procedures were used to check reliability: Cronbach alpha and reliability between evaluators, Results were established at the 10th percentile, and an alert point per task for each normative group. Cronbach's alpha was, in general, between .70 and .90 and the average rate of agreement between evaluators varied from .62 to .94. Standards of age and education were established. The reliability of this instrument was verified. The psychometric legitimization of the MEC Battery will contribute to the diagnostic process for communicative disorders.     

Locus of the redundant-signals effect in bimodal divided attention: A neurophysiological analysis

We reanalyzed the data from the study of Lamarre, Busby, and Spidalieri (1983). In that study, the activity of single neurons in area 4 of the motor cortex was recorded during a bimodal detection task in which a monkey (Macaca mulatta)had to respond as quickly as possible to a visual or an auditory signal or to both (redundant trials). Manual responses on redundant trials were speeded by the presence of both signals, as is typically found. The times between signal onsets and the first changes in neuronal activity were also speeded by redundant signals, but there was no difference between redundant-signals and single-signal trials in the time between the change in neuronal activity and movement onset. These results suggest that late motor processes are not speeded by redundant signals in bimodal detection tasks.     

Emotions and false memories: valence or arousal?

The effects of mood on false memories have not been studied systematically until recently. Some results seem to indicate that negative mood may reduce false recall and thus suggest an influence of emotional valence on false memory. The present research tested the effects of both valence and arousal on recall and recognition and indicates that the effect is actually due to arousal. In fact, whether participants' mood is positive, negative, or neutral, false memories are significantly more frequent under conditions of high arousal than under conditions of low arousal.     

Machiavellianism and Economic Opportunism

This study explores the relationship between 2 defecting strategies based on the manipulation of information; namely, Machiavellianism and economic opportunism. There are 3 main hypotheses that were confirmed in questionnaire investigations among samples of 191 and 113 university students in Athens. Machiavellianism was positively correlated with economic opportunism, shown by a statistically highly significant positive correlation between scores on scales measuring these 2 concepts. In situations of asymmetric information where they held the advantage, high Machs adopted more opportunistic strategies, showing the greatest inclination to maximize their own profit. High Machs showed less trust in potential economic partners, whom they regarded as untrustworthy maximizers.