Responses toward a trapped animal by wild bonobos at Wamba

Chimpanzees and bonobos are the closest living relatives of humans and diverged relatively recently in their phylogenetic history. However, a number of reports have suggested behavioral discrepancies between the two Pan species, such as more cooperative and tolerant social interaction and poorer tool-using repertoires in bonobos. Concerning hunting behavior and meat consumption, recent studies from the field have confirmed both behaviors not only in chimpanzees but also in bonobos. The present study reports an encounter by wild bonobos at Wamba with a duiker trapped in a snare. Bonobos interacted with the live duiker for about 10 min but did not eventually kill the animal. They showed fear responses when the duiker moved and exhibited behaviors related to anxiety and stress such as branch-drag displays and self-scratching. Although bonobos manipulated nearby saplings and parts of the snare, they did not use detached objects to make indirect contact with the duiker. Juveniles and adults of both sexes engaged in active interactions with the trapped duiker. Overall, bonobos’ behavioral responses indicated species-specific cognitive characteristics largely different from those of chimpanzees.     

Prior cognitive activity implicitly modulates subsequent emotional responses to subliminally presented emotional stimuli

It has been reported that engagement in several kinds of cognitive activity can successfully inhibit unpleasant emotions. In this study, we tried to replicate the previous finding that cognitive activity can modulate subsequent psychological and physiological emotional processes and to investigate whether prior cognitive activity can attenuate implicit emotional processes triggered by subliminal emotional stimuli. Sixty students were randomly divided into three groups (cognitive task group, noncognitive task group, control group). The cognitive task group was asked to engage in an n-back task, while the control group was asked to stay calm. The noncognitive task group was asked to do a handgrip-squeezing task. All participants then engaged in a version of a subliminal affective priming task where they were unconsciously exposed to affectively negative pictures. The cognitive task group showed lower negative experiences after the subliminal affective priming task and a substantial reduction in their heart rate responses, as compared with the other groups. These results provide evidence that engagement in cognitive activity can attenuate emotional processes in an automatic and unconscious manner.     

The role of the input on the development of the LC bias: A crosslinguistic comparison

Previous studies have described the existence of a phonotactic bias called the Labial–Coronal (LC) bias, corresponding to a tendency to produce more words beginning with a labial consonant followed by a coronal consonant (i.e. “bat”) than the opposite CL pattern (i.e. “tap”). This bias has initially been interpreted in terms of articulatory constraints of the human speech production system. However, more recently, it has been suggested that this presumably language-general LC bias in production might be accompanied by LC and CL biases in perception, acquired in infancy on the basis of the properties of the linguistic input. The present study investigates the origins of these perceptual biases, testing infants learning Japanese, a language that has been claimed to possess more CL than LC sequences, and comparing them with infants learning French, a language showing a clear LC bias in its lexicon. First, a corpus analysis of Japanese IDS and ADS revealed the existence of an overall LC bias, except for plosive sequences in ADS, which show a CL bias across counts. Second, speech preference experiments showed a perceptual preference for CL over LC plosive sequences (all recorded by a Japanese speaker) in 13- but not in 7- and 10-month-old Japanese-learning infants (Experiment 1), while revealing the emergence of an LC preference between 7 and 10 months in French-learning infants, using the exact same stimuli. These crosslinguistic behavioral differences, obtained with the same stimuli, thus reflect differences in processing in two populations of infants, which can be linked to differences in the properties of the lexicons of their respective native languages. These findings establish that the emergence of a CL/LC bias is related to exposure to a linguistic input.     

Justice Orientation as a Moderator of the Framing Effect on Procedural Justice Perception

Justice orientation is a justice-relevant personality trait, which is referred to as the tendency to attend to fairness issues and to internalize justice as a moral virtue. This study examined the moderating role of justice orientation in the relationship between justice perception and response to a decision problem. The authors manipulated procedural justice and the outcome valence of the decision frame within a vignette, and measured justice orientation of 174 Japanese participants. As hypothesized, the results indicated an interaction between procedural justice and framing manipulation, which was moderated by individual differences in justice orientation. In negative framing, justice effects were larger for individuals with high rather than low justice orientation. The results are explained from a social justice perspective, and the contributions and limitations of this study are also discussed with respect to our sample and framing manipulation.     

Young children's moral judgments of commission and omission related to the understanding of Knowledge or Ignorance

This study examined developmental change in young children's moral judgments of commission and omission related to mental states, especially knowledge or ignorance. 4–5 and 5‐ to 6‐year‐olds (n=67) made moral judgments about the tasks related to the understanding of knowledge or ignorance. The tasks were also composed of two types of acts: commission or omission. The results showed that the both age groups understood knowledge and ignorance, but that the older group made moral judgments based on this understanding more similar to adults compared to the younger group. There was not an age difference concerning whether the acts were of commission or omission. These findings indicate that there is no difference for young children in the difficulty in moral judgments of acts of commission and omission related to mental states, whereas there is a developmental difference in using the understanding of knowledge or ignorance for making moral judgments. Copyright © 2009 John Wiley & Sons, Ltd.     

Cultural grounding of regret: Regret in self and interpersonal contexts

The purpose of this study was to explore cultural similarities and differences in regret, focusing on distinctions between interpersonal and self-situations, and between action and inaction regrets. Japanese and American undergraduates were asked to describe regrets experienced in interpersonal and self-situations. We found that both situational and cultural contexts influenced the likelihood of regretting inactions over actions. Participants were more likely to recall inaction regrets in self-situations than in interpersonal situations, and that the likelihood of recalling inaction regrets was more pronounced for Americans than for Japanese. Furthermore, we examined the intensity of the regret. Whereas American students experienced regret as intense as that of Japanese students in self-situations, Japanese students experienced regret more strongly than American students in interpersonal situations. Detailed content analysis also showed that individuals experienced regret in ways consistent with cultural values. The situational and cultural grounding of regret is discussed.     

A left cerebral hemisphere’s superiority in processing spatial-categorical information in a non-verbal semantic format

It has been shown that the left and right cerebral hemispheres (LH and RH) respectively process qualitative or “categorical” spatial relations and metric or “coordinate” spatial relations. However, categorical spatial information could be thought as divided into two types: semantically-coded and visuospatially-coded categorical information. We examined whether a LH’s advantage in processing semantic-categorical information is observed in a non-verbal format, and also whether semantic- and visuospatial-categorical processing are differentially lateralized. We manipulated the colors and positions of the standard traffic light sign as semantic- and visuospatial-categorical information respectively, and tested performance with the divided visual field method. In the semantic-categorical matching task, in which the participants judged if the semantic-categorical information of a successive cue and target was the same, a right visual field advantage was observed, suggesting a LH’s preference for processing semantic-categorical information in a non-verbal format. In the visuospatial-categorical matching task, in which the participants judged if the visuospatial-categorical information of a successive cue and target was identical, a left visual field advantage was obtained. These results suggest that the processing of semantic-categorical information is lateralized in LH, and we discuss the dissociation between the two types of categorical information.     

Temporal patterns of behavior from the scheduling of psychology quizzes

Temporal patterns of behavior have been observed in real-life performances such as bill passing in the U.S. Congress, in-class studying, and quiz taking. However, the practical utility of understanding these patterns has not been evaluated. The current study demonstrated the presence of temporal patterns of quiz taking in a university-level introductory psychology course and used these patterns to manage the traffic of quiz takers in a computerized testing lab. Results are discussed in terms of the applications of tracking temporal response patterns.     

Feature selection for inductive generalization

Judging similarities among objects, events, and experiences is one of the most basic cognitive abilities, allowing us to make predictions and generalizations. The main assumption in similarity judgment is that people selectively attend to salient features of stimuli and judge their similarities on the basis of the common and distinct features of the stimuli. However, it is unclear how people select features from stimuli and how they weigh features. Here, we present a computational method that helps address these questions. Our procedure combines image-processing techniques with a machine-learning algorithm and assesses feature weights that can account for both similarity and categorization judgment data. Our analysis suggests that a small number of local features are particularly important to explain our behavioral data.