Variability in the “stereotyped” prey capture sequence of male cuttlefish (<Emphasis Type="Italic">Sepia officinalis</Emphasis>) could relate to personality differences

Studies of animal personality have shown consistent between-individual variation in behaviour in many social and non-social contexts, but hunting behaviour has been overlooked. Prey capture sequences, especially in invertebrates, are supposed to be quite invariant. In cuttlefish, the attack includes three components: attention, positioning, and seizure. The previous studies indicated some variability in these components and we quantified it under the hypothesis that it could relate to personality differences. We, therefore, analysed predation sequences of adult cuttlefish to test their association with personality traits in different contexts. Nineteen subjects were first exposed to an “alert” and a “threat” test and then given a live prey, for 10 days. Predation sequences were scored for components of the attack, locomotor and postural elements, body patterns, and number of successful tentacle ejections (i.e. seizure). PCA analysis of predatory patterns identified three dimensions accounting for 53.1%, 15.9%, and 9.6% of the variance and discriminating individuals based on “speed in catching prey”, “duration of attack behaviour”, and “attention to prey”. Predation rate, success rate, and hunting time were significantly correlated with the first, second, and third PCA factors, respectively. Significant correlations between capture patterns and responsiveness in the alert and threat tests were found, highlighting a consistency of prey capture patterns with measures of personality in other contexts. Personality may permeate even those behaviour patterns that appear relatively invariant.     

Adolescent romantic relationships as a tug of war: The interplay of power imbalance and relationship duration in adolescent dating aggression

The present study investigates the link between power imbalance within the romantic couple and psychological, relational and physical adolescent dating aggression (ADA) perpetration, considering also the role of relationship duration as an indicator of the developmental stage of the relationship. This is the first investigation into whom is perceived to have power in the relationship (the partner or the subject him/herself) by distinguishing between male and female adolescents. Participants were 805 Italian adolescents (36.1% males; 63.9% females) aged 14–20 years (M_age = 17.16 years, SD_age = 1.34), all reporting having been in a romantic relationship currently or within the past 6 months. Males perceiving a balanced relationship reported lower levels of psychological ADA perpetration, and they perpetrated more relational ADA in longer relationships where the partner is perceived to have the power. No significant findings emerged regarding physical ADA. Females perceiving themselves as having the power in the relationship reported higher levels of psychological and physical ADA perpetration. They perpetrated more relational ADA when they perceived the partner as having the power in the relationship. Also, females in longer relationships in which power was not perceived as equally shared between partners reported higher physical ADA perpetration. Finally, for both males and females, longer relationships were characterized by higher levels of ADA toward the partner. Findings highlight the importance of studying the interplay between power imbalance and relationship duration on ADA perpetration, and provide the way to understand possible functions of ADA within a romantic relationship.     

Identity concept learning in matching-to-sample tasks by tufted capuchin monkeys (Cebus apella)

The abstract concept of equivalence is considered one of the bases of higher-order cognition, and it has been the subject of considerable research in comparative cognition. This study examined the conditions under which tufted capuchin monkeys (Cebus apella) are able to acquire an identity concept. Six capuchin monkeys were trained to solve a visual matching-to-sample (MTS) task on the basis of perceptual identity. The acquisition of the identity rule was inferred from the subject’s ability to solve transfer tests with novel stimuli. We evaluated the ability of the capuchin monkeys to match the shape of novel stimuli after training with both several small stimulus sets (Experiment 1) and a large stimulus set (Experiment 2). Moreover, we examined the ability of capuchins to transfer the concept to novel visual dimensions, such as colour and size and to transfer to novel spatial arrangements of the stimuli (Experiment 2). We demonstrated that the ability of capuchins to match novel stimuli was improved by increasing the number of stimuli used during training (Experiments 1 and 2) and that after a widely applicable identity concept based on the stimulus shape was acquired, the capuchins were able to match stimuli according to an identity rule based on both the colour and size of the stimuli and when the spatial arrangement of the stimuli was varied (Experiment 2). This study is the first to demonstrate that the size of the training set affects the acquisition of an abstract identity concept in an MTS task in non-human primates.     

Media exposure to terrorism and people's risk perception: The role of environmental sensitivity and psychophysiological response to stress

Terrorist attacks have a destabilizing impact on the general population, causing distress and fear. However, not all individuals are equally susceptible to the effects of terror threat. This study aimed to examine whether exposure to terrorism-related pictures interacted with individual differences in environmental sensitivity and psychophysiological response to stress to explain people's risk perception, operationalized as perceived likelihood of a terrorist attack and willingness to trade off one's privacy to increase national security. Ninety-five university students were randomly assigned to one of two conditions (terrorism-related vs. neutral pictures). After watching the pictures, they answered questions concerning risk perception and completed questionnaires. Stress was induced by the Mannheim Multicomponent Stress Test, during which heart rate was recorded. Results showed that the perceived likelihood of future attacks was affected by the interaction between exposure to terrorism pictures and psychophysiological reactivity to stress, whereas willingness to trade off one's privacy to improve national security was influenced by the interaction between exposure to terrorism pictures and environmental sensitivity. The study suggests that individuals high in sensitivity and psychophysiological stress reactivity are particularly affected by terrorism-related pictures. Psychologists should direct their efforts to raise general awareness of the negative effects, especially for some people, of such media coverage.     

Audience design affects acoustic reduction via production facilitation

In this article, we examine the hypothesis that acoustic variation (e.g., reduced vs. prominent forms) results from audience design. Bard et al. (Journal of Memory and Language 42:1-22, 2000) have argued that acoustic prominence is unaffected by the speaker's estimate of addressee knowledge, using paradigms that contrast speaker and addressee knowledge. This question was tested in a novel paradigm, focusing on the effects of addressees' feedback about their understanding of the speaker's intended message. Speakers gave instructions to addressees about where to place objects (e.g., the teapot goes on red). The addressee either anticipated the object, by picking it up before the instruction, or waited for the instruction. For anticipating addressees, speakers began speaking more quickly and pronounced the word the with shorter duration, demonstrating effects of audience design. However, no effects appeared on the head noun (e.g., teapot), as measured by duration, amplitude, and perceived intelligibility. These results are consistent with a mechanism in which evidence about addressee understanding facilitates production processes, as opposed to triggering particular acoustic forms.     

Lack of control enhances accurate and inaccurate identification responses to degraded visual objects

Recent studies have shown that lack of control induces illusory pattern perception. In this study, we demonstrate that lacking control also affected identification responses to degraded pictures of visual objects. As compared with control participants, participants in whom lack of control was experimentally induced produced identification responses to visual objects at a significantly higher level of degradation of the stimulus. Lacking control did not influence accuracy of identification, since the effect was present for both correct and incorrect identification responses, and did not encourage pure random guessing. Our results indicate that lacking control makes individuals more prone to achieve visual closure by attempting earlier identifications of perceptually degraded visual objects. Possible mechanisms involved in this effect are discussed.     

Covert reading of letters in a case of global alexia

This study describes the case of a global alexic patient with a severe reading deficit affecting words, letters and Arabic numbers, following a left posterior lesion. The patient (VA) could not match spoken letters to their graphic form. A preserved ability to recognize shape and canonical orientation of letters indicates intact access to the representation of letters and numbers as visual objects. A relatively preserved ability to match lowercase to uppercase letters suggests partially spared access to abstract letter identities independently of their visual forms. The patient was also unable to match spoken letters and numbers to their visual form, indicating that she could not access the graphemic representations of letters from their phonological representations. This pattern of performance suggests that the link between graphemic and phonological representations is disrupted in this patient. We hypothesize that VA’ residual reading abilities are supported by the right hemisphere.     

Similarity, Cohesion, and Friendship Networks Among Boys and Girls: A One-Year Follow-Up Study Among Italian Children

This study aimed to investigate the follow-up effects of certain characteristics of children??s friendships, such as similarity and cohesion with friends as represented by the children through drawing, as well as the breadth of their friendship networks as perceived by children. Participants were 115 children who were 6 to 9?years old (M?=?7.09.14, SD?=?0.41; 51?% female), attending two primary schools in northwest Italy. We used children??s drawings and self-reported measures to investigate friendship at both dyadic and network levels. Multiple logistic regressions indicated that mean score of similarity was positively associated with friendship network while an increase in cohesion was negatively associated with friendship network at follow-up. These associations did not vary by sex and stability or change of drawn friend. The paper contributes to the knowledge on the subject of friendship among children, especially in light of its focus on the associations between the components of friendship and the friendship network. Findings demonstrated that boys and girls are much more similar than expected.