Recurrence plot analyses suggest a novel reference system involved in newborn spontaneous movements

The movements of newborns have been thoroughly studied in terms of reflexes, muscle synergies, leg coordination, and target-directed arm/hand movements. Since these approaches have concentrated mainly on separate accomplishments, there has remained a clear need for more integrated investigations. Here, we report an inquiry in which we explicitly concentrated on taking such a perspective and, additionally, were guided by the methodological concept of home base behavior, which Ilan Golani developed for studies of exploratory behavior in animals. Methods from nonlinear dynamics, such as symbolic dynamics and recurrence plot analyses of kinematic data received from audiovisual newborn recordings, yielded new insights into the spatial and temporal organization of limb movements. In the framework of home base behavior, our approach uncovered a novel reference system of spontaneous newborn movements.     

Re-analysis of correlations among four impulsivity scales

Impulsivity plays a key role in normal and pathological behavior. Although there is some consensus about its conceptualization, there have been many attempts to build a multidimensional tool due to the lack of agreement in how to measure it. A recent study claimed support for a three-dimensional structure of impulsivity, however with weak empirical support. By re-analysing those data, a four-factor structure was found to describe the correlation matrix much better. The debate remains open and further research is needed to clarify the factor structure. The desirability of constructing new measures, perhaps analogously to the Wechsler Intelligence Scale, is emphasized.     

Eighteen month test-retest stability of the youth self report in a sample of Catalonian adolescents

The aim of this study is to assess the test-retest stability of the Spanish version of Youth Self Report after 18 mo. for a sample of 357 Catalonian high school students (158 boys and 199 girls). At Time 2 the girls' scores increased on Delinquent and Aggressive Behavior scales and, therefore on Externalizing scores. At Time 2 the boys' scores increased on Attention Problems and Delinquent Behavior and decreased on Anxious/Depressed, Social Problems, and Internalizing scales. Significant differences in the remaining scales were not observed. The test-retest intraclass correlations for the broad-band scales ranged between .62 (Internalizing) and .68 (Externalizing) and for the narrow-band scales between .37 and .67. The correlations for girls and boys were similar but slightly higher for girls on Anxious/Depressed and Thought Problems.     

Associative activation of stimulus representations restores lost salience: implications for perceptual learning

In 3 experiments, rats received preexposure to presentations of a compound flavor BX. The effective salience of B was then tested by assessing its ability to interfere with the aversion controlled by another flavor or the tendency to drink a saline solution after the induction of a salt need. It was found that the effective salience of B was maintained when during preexposure, presentations of BX alternated with presentations of X alone. This was true both when BX was presented as a simultaneous compound (Experiment 1) and as a serial compound (X-->B; Experiments 2 and 3); salience was not maintained when the serial compound took the form B-->X (Experiments 2 and 3a). It was argued that the salience of B declines during preexposure but is restored when presentations of X are able to activate the representation of B by way of the associative X-B link.     

Errors in judging information about reflections in mirrors

We investigated people's perception and knowledge of planar mirror reflections. People were accurate at deciding when they could first see their reflection as they approached a mirror from the side, but only if their reflection was visible. Most people stopped too early if the mirror was covered up. People also overestimated the size of the reflection of their face on the surface of a mirror if they were shown a covered mirror. Their accuracy improved somewhat if their reflection was visible but, unlike the first task, they still made striking errors. Perceptual feedback thus improved performance at predicting the behaviour of mirror reflections in both tasks but failed to eliminate errors in the second task. The overestimation of reflection size was not face-specific as it generalised to novel stimuli (paper ellipses) and it was found with both a matching response and for verbal size estimations. The early error in the first task appears to be due to an inaccurate belief that can be overridden by perceptual feedback. The overestimation in the second task is primarily caused by a powerful size-constancy effect.     

The nature of residual cost in regular switch response factors

Two experiments are presented that compare the residual cost found when switching from one task to another under predictable conditions. The aim of the study was to explore the roles played by the stimulus, the response, or both in the process of the mental set reconfiguration necessary to switch between two tasks. The experiments tested [Rogers, R. D., & Monsell, S. (1995). Cost of a predictable switch between simple cognitive tasks. Journal of Experimental Psychology: General, 124, 207-231] stimulus-cued-completion hypothesis and [Schuch, S., & Koch, I. (2003). The role of response selection for inhibition of task sets in task shifting. Journal of Experimental Psychology: Human Perception and Performance, 29, 92-105] hypothesis of response selection as the key factor in the nature of switch cost. In the first experiment, two conditions were created that varied in terms of a Go/No-Go signal: The Go trials were a replication of [Tornay, F. J., & Milán, E. G. (2001). A more complete task-set reconfiguration in random than in predictable task switch. The Quarterly Journal of Experimental Psychology, 54A, 785-803 Experiment 3]; The No-Go trials were identical to the first condition, except that participants did not execute a response in the trial n-1 (Schuch & Koch, 2003). In addition, the percentage of Go and No-Go trials was manipulated. The results showed that the cost was significant only in the high Go signal-frequency case (Experiment 2), with an abrupt offset in Go trials and a gradual offset in No-Go trials. Based on the results of these experiments, it was concluded that the crucial factor to complete a mental set reconfiguration is response-related and not stimulus-related.     

Amodal completion and visual holes (static and moving)

Occlusion is a frequent occurrence in a cluttered world of opaque objects. Often information about the shape of partly occluded objects can be gathered from the visible portion of the object and in particular its contours. Here we address the case where a region of a surface is visible exclusively through an aperture (visual hole). We make several observations about the grouping of surface regions visible through holes, and the appearance of moving objects and holes. These observations support the view that holes are shape properties of the object-with-hole.     

Generalization of tacting actions in children with autism

This intervention compared the effects of two procedures on the generalization of a tacting repertoire (labeling) in 6 children with autism spectrum disorder. In one procedure the verbal antecedent stimulus “What is she doing?” appeared together with a person performing an action; in the other procedure, the antecedent stimulus was just the presence of the action. In initial tests, children emitted tacts only when the action was presented with the verbal antecedent. Thereafter, they learned to tact an action without the verbal antecedent and received tests to evaluate generalization to another action. Results indicated that in order to obtain generalization of tacting actions, it was necessary to learn to tact other actions without the verbal antecedent as well as learning to tact the action with the verbal antecedent. These findings have relevance for generalization of tacting actions from control by verbal antecedents to natural conditions and the production of spontaneous language.     

Arbitrariness and the death penalty: how the defendant's appearance during trial influences capital jurors' punishment decision

This paper examines the impact of the defendant's appearance during the trial on capital jurors' punishment decision. The data used in this analysis were gathered by the Capital Jury Project (CJP), a national program of research on the decision-making of capital jurors. A series of multivariate logistic regression analyses were conducted using four aggravating circumstances related to the killing and eight defendant appearance variables as predictors of jurors' punishment decision at three points during the capital trial: (1) after the punishment phase ended, but before formal deliberation began; (2) when the first vote was taken on punishment at jury deliberations; and (3) at the final vote on punishment. Results indicated that when the defendant appeared emotionally involved during the trial (i.e. sorry and sincere) jurors either favored a life sentence or were undecided about punishment; however, when the defendant appeared emotionally uninvolved during the trial (i.e. bored) jurors either sought a death sentence or remained undecided. Policy implications will be discussed.