Closed-loop bird–computer interactions: a new method to study the role of bird calls

In the field of songbird research, many studies have shown the role of male songs in territorial defense and courtship. Calling, another important acoustic communication signal, has received much less attention, however, because calls are assumed to contain less information about the emitter than songs do. Birdcall repertoire is diverse, and the role of calls has been found to be significant in the area of social interaction, for example, in pair, family, and group cohesion. However, standard methods for studying calls do not allow precise and systematic study of their role in communication. We propose herein a new method to study bird vocal interaction. A closed-loop computer system interacts with canaries, Serinus canaria, by (1) automatically classifying two basic types of canary vocalization, single versus repeated calls, as they are produced by the subject, and (2) responding with a preprogrammed call type recorded from another bird. This computerized animal–machine interaction requires no human interference. We show first that the birds do engage in sustained interactions with the system, by studying the rate of single and repeated calls for various programmed protocols. We then show that female canaries differentially use single and repeated calls. First, they produce significantly more single than repeated calls, and second, the rate of single calls is associated with the context in which they interact, whereas repeated calls are context independent. This experiment is the first illustration of how closed-loop bird–computer interaction can be used productively to study social relationships.     

Cross-validation of the very short form of the Physical Self-Inventory (PSI-VS): invariance across genders, age groups, ethnicities and weight statuses

In a recent review of various physical self-concept instruments, Marsh and Cheng (in press) noted that the very short 12-item version of the French Physical Self-Inventory (PSI-VS) represents an important contribution to applied research but that further research was needed to investigate the robustness of its psychometric properties in new and diversified samples. The present study was designed to answer these questions based on a sample of 1103 normally achieving French adolescents. The results show that the PSI-VS measurement model is quite robust and fully invariant across subgroups of students formed according to gender, weight, age and ethnicity. The results also confirm the convergent validity and scale score reliability of the PSI-VS subscales.     

The development of prosocial behaviors in young children: a prospective population-based cohort study

Researchers know relatively little about the normative development of children's behaviors aimed at alleviating distress or discomfort in others. In this article, the authors aim to describe the continuity and discontinuity in the degree to which young children in the general population are reported to exhibit specific prosocial behaviors. Data came from the Québec Longitudinal Study of Child Development. Consistent with Hay's model of prosocial development, the results show that there were about as many children who stopped exhibiting prosocial behaviors between 29 and 41 months of age as there were children who started doing so during this period. Further, gender differences (girls > boys) in prosocial behaviors are either emerging or at least increasing in magnitude, with girls being more likely to start and boys being more likely to stop exhibiting these behaviors between 29 and 41 months of age. Consistent with the early-onset hypothesis, children who exhibit prosocial behaviors at 17 months of age are less likely to stop exhibiting the same behaviors between 29 and 41 months of age. Otherwise, if they did not exhibit prosocial behaviors at 29 months of age, they are also more likely to start doing so in the following year.     

When Drivers See Red: Car Color Frustrators and Drivers’ Aggressiveness

Research has found that exposition to red is associated with physiological activation and fighting spirit. A field experiment was conducted to explore whether the color of cars is related to an aggressive response. Drivers waiting at a traffic light were blocked by an experimental car. The color of the car varied (blue, red, green, black, and white). The amount of time that elapsed until the drivers responded by honking their horns or beaming their headlights was the dependent variable. It was found that the red car elicited early aggressive response.     

Le « test par CDD » comme frein au fonctionnement des entreprises

In France, in order to evaluate job applicants, some employers use short term contract before recruiting on a long term contract. The present study aims to compare companies having this practice and others. More precisely, we will appreciate the level of recruitment difficulties and the degree of fundamental error of attribution according companies. Results indicate that companies having “test by CDD” have more recruitment difficulties and more fundamental error of attribution to explain these failures.     

Factor structure and measurement invariance of a short measure of the Big Five personality traits

The main purpose of this study is to assess the factor structure and the measurement invariance of the Mini-International Personality Item Pool (Mini-IPIP; Donnellan, Oswald, Baird, & Lucas, 2006). The Mini-IPIP is a brief instrument evaluating personality traits according to the Big Five models. Two samples were collected comprising nearly 800 participants. Confirmatory factor analyzes revealed a five-factor solution consistent with the Big Five model. Measurement invariance analyses showed that the Mini-IPIP was reasonably invariant across samples, genders and age groups. Overall, results pointed to a satisfactory factorial structure and an adequate invariance of the measure.     

The Development of Prosocial Behaviors in Young Children: A Prospective Population-Based Cohort Study

Researchers know relatively little about the normative development of children's behaviors aimed at alleviating distress or discomfort in others. In this article, the authors aim to describe the continuity and discontinuity in the degree to which young children in the general population are reported to exhibit specific prosocial behaviors. Data came from the Québec Longitudinal Study of Child Development. Consistent with Hay's model of prosocial development, the results show that there were about as many children who stopped exhibiting prosocial behaviors between 29 and 41 months of age as there were children who started doing so during this period. Further, gender differences (girls > boys) in prosocial behaviors are either emerging or at least increasing in magnitude, with girls being more likely to start and boys being more likely to stop exhibiting these behaviors between 29 and 41 months of age. Consistent with the early-onset hypothesis, children who exhibit prosocial behaviors at 17 months of age are less likely to stop exhibiting the same behaviors between 29 and 41 months of age. Otherwise, if they did not exhibit prosocial behaviors at 29 months of age, they are also more likely to start doing so in the following year.     

Door-in-the-face technique and monetary solicitation: an evaluation in a field setting

To test the door-in-the-face technique for a private solicitation, 53 men and 37 women in several bars were engaged. In one condition, a female confederate asked the subject to buy her drink because her boyfriend had left without paying the bill. After the subject refused, the confederate requested only 2 or 3 coins. In the control condition, the latter request was the only one. Analysis showed a dramatic increase in compliance for the door-in-the-face condition. A positive effect of the door-in-the-face technique was also observed for the average amount of the donation. The accentuation of the solicitor's dependency in the door-in-the-face condition seemed relevant for explanation.     

Rapid induction of specific associative behavioral memory by stimulation of the nucleus basalis in the rat

Hypothesized circuitry enabling behavioral memory formation can be tested by its direct activation in the absence of normal experience. Neuromodulation via the cortical release of acetylcholine by the nucleus basalis (NB) is hypothesized to be sufficient to induce specific, associative behavioral memory. Previously, we found that tone paired with stimulation of the nucleus basalis (NBs) for 3000 trials over 15 days induced such memory, supporting the hypothesis. However, as standard associative memory can be established much more rapidly, we asked whether NB-induced memory develops rapidly. Adult male Sprague-Dawley rats, trained and tested in the same calm, waking state, were divided into Paired (n=5) and control (n=4) groups, each of which received a single session of 200 trials of an 8.0 kHz conditioned stimulus (CS) either paired with NBs or with unpaired presentation of NBs. Respiration, cardiac activity, and evoked potentials in the primary auditory cortex (ACx) were recorded. Memory and its degree of specificity were assessed 24 h later by presenting tones of various frequencies (1-15 kHz) in the absence of NBs to yield behavioral frequency generalization gradients. Behavioral responses to test tones consisted of interruption of ongoing respiration and changes in heart rate. Post-training behavioral generalization gradients exhibited response peaks centered on the CS frequency for the Paired group alone. Tone evoked potentials from the ACx also developed CS-specific plasticity. The findings indicate that NB induction of specific behavioral associative memory, like normal memory, can develop rapidly and is accompanied by specific cortical plasticity, supporting the view that NB engagement during normal learning produces memory.     

Evidence for an attentional component of the perceptual misalignment between moving and flashing stimuli

If a pair of dots, diametrically opposed to each other, is flashed in perfect alignment with another pair of dots rotating about the visual fixation point, most observers perceive the rotating dots as being ahead of the flashing dots (flash-lag effect). This psychophysical effect was first interpreted as the result of a perceptual extrapolation of the position of the moving dots. Also, it has been conceived as the result of differential visual latencies between flashing and moving stimuli, arising from purely sensory factors and/or expressing the contribution of attentional mechanisms as well. In a series of two experiments, we had observers judge the relative position between rotating and static dots at the moment a temporal marker was presented in the visual field. In experiment 1 we manipulated the nature of the temporal marker used to prompt the alignment judgment. This resulted in three main findings: (i) the flash-lag effect was observed to depend on the visual eccentricity of the flashing dots; (ii) the magnitude of the flash-lag effect was not dependent on the offset of the flashing dot; and (iii) the moving stimulus, when suddenly turned off, was perceived as lagging behind its disappearance location. Taken altogether, these results suggest that neither visible persistence nor motion extrapolation can account for the perceptual flash-lag phenomenon. The participation of attentional mechanisms was investigated in experiment 2, where the magnitude of the flash-lag effect was measured under both higher and lower predictability of the location of the flashing dot. Since the magnitude of the flash-lag effect significantly increased with decreasing predictability, we conclude that the observer's attentional set can modulate the differential latencies determining this perceptual effect. The flash-lag phenomenon can thus be conceived as arising from differential visual latencies which are determined not only by the physical attributes of the stimulus, such as its luminance or eccentricity, but also by attentional mechanisms influencing the delays involved in the perceptual processing.