The reciprocal relation between sleep and memory in infancy: Memory‐dependent adjustment of sleep spindles and spindle‐dependent improvement of memories

Sleep spindle activity in infants supports their formation of generalized memories during sleep, indicating that specific sleep processes affect the consolidation of memories early in life. Characteristics of sleep spindles depend on the infant's developmental state and are known to be associated with trait‐like factors such as intelligence. It is, however, largely unknown which state‐like factors affect sleep spindles in infancy. By varying infants’ wake experience in a within‐subject design, here we provide evidence for a learning‐ and memory‐dependent modulation of infant spindle activity. In a lexical‐semantic learning session before a nap, 14‐ to 16‐month‐old infants were exposed to unknown words as labels for exemplars of unknown object categories. In a memory test on the next day, generalization to novel category exemplars was tested. In a nonlearning control session preceding a nap on another day, the same infants heard known words as labels for exemplars of already known categories. Central–parietal fast sleep spindles increased after the encoding of unknown object–word pairings compared to known pairings, evidencing that an infant's spindle activity varies depending on its prior knowledge for newly encoded information. Correlations suggest that enhanced spindle activity was particularly triggered, when similar unknown pairings were not generalized immediately during encoding. The spindle increase triggered by previously not generalized object–word pairings, moreover, boosted the formation of generalized memories for these pairings. Overall, the results provide first evidence for a fine‐tuned regulation of infant sleep quality according to current consolidation requirements, which improves the infant long‐term memory for new experiences.     

On the examination couch: the relationship between the egocentric perspective and the attentional focus

Determined by anatomical characteristics, the binocular visual field has an elliptical shape. Whereas the focus of attention – that area of the visual field in which objects can be consciously perceived – is significantly smaller, its shape is not necessarily dependent on the same factors. Indeed, it is yet unknown if the maximum extents of the attentional focus’ meridians are dimensionally stable or adapt to the egocentric perspective. In this study, we intended to measure the expansion up to which peripheral stimuli can still be perceived while participants were sitting and lying on the left and on the right body side. Results demonstrate that contrary to the visual field the maximum extents along the attentional focus’ meridians remain stable across different head positions with a greater horizontal than vertical alignment. This indicates that the expansion ratios of the meridians of the attentional focus are not dependent on the egocentric perspective. Rather, they appear stable in space and gravity-based. Findings are discussed in terms of our visual environment and current as well as alternative interpretations are weighed against each other.     

Using Automated Learning Devices for Monkeys (ALDM) to study social networks

Social network analysis has become a prominent tool to study animal social life, and there is an increasing need to develop new systems to collect social information automatically, systematically, and reliably. Here we explore the use of a freely accessible Automated Learning Device for Monkeys (ALDM) to collect such social information on a group of 22 captive baboons (Papio papio). We compared the social network obtained from the co-presence of the baboons in ten ALDM testing booths to the social network obtained through standard behavioral observation techniques. The results show that the co-presence network accurately reflects the social organization of the group, and also indicate under which conditions the co-presence network is most informative. In particular, the best correlation between the two networks was obtained with a minimum of 40 days of computer records and for individuals with at least 500 records per day. We also show through random permutation tests that the observed correlations go beyond what would be observed by simple synchronous activity, to reflect a preferential choice of closely located testing booths. The use of automatized cognitive testing therefore presents a new way of obtaining a large and regular amount of social information that is necessary to develop social network analysis. It also opens the possibility of studying dynamic changes in network structure with time and in relation to the cognitive performance of individuals.     

Group and individual stereotype threat and identity management strategies: An investigation of rugby women

The aim of this study was to test the gender identification effect on the stereotype threat (ST) experience felt, and whether the individual or group ST experience influenced the identity management strategies. Ninety‐six French rugby women were asked to imagine a training situation in which they practiced rugby in the presence of men. Results showed that the group identification did not affect Individual or Group ST and that the more women feel an individual ST the more they assess men's ability positively, and the less they assesses women's ability positively and that the more they feel a group ST the more they assess the ability of women positively. The theoretical and practical implications of these results are discussed.     

The role of pain behaviour and family caregiver responses in the link between pain catastrophising and pain intensity: A moderated mediation model

Objectives: This study investigated the mediating role of pain behaviours in the association between pain catastrophising and pain intensity and explored the moderating role of family caregivers’ responses to pain in the link between pain behaviours and pain intensity.

Methods: The sample consisted of 154 chronic pain patients and their family caregivers. Patients completed questionnaires regarding pain intensity, pain catastrophising, pain behaviours and their caregivers’ responses to their pain. Family caregivers reported their responses to the patients’ pain.

Results: Pain catastrophising was associated with pain intensity (r = 0.37) and pain behaviours partly mediated this association. The positive association between pain behaviours and pain intensity was significant only if patients reported that their family caregivers showed high levels of solicitous (effect = .49) and distracting responses (effect = .58), and if caregivers reported to show high levels of solicitous responses (effect = .51). No support was found for negative responses as a moderator neither based on patients’ perception of negative responses nor based on caregivers’ perception of negative responses.

Conclusions: The findings are in line with the idea that family caregivers’ solicitous and distracting responses convey to patients that their condition is serious, which may reinforce patients’ pain and pain behaviours, especially in those who catastrophise.     

Child-Oriented or Parent-Oriented Focused Intervention: Which is the Better Way to Decrease Children’s Externalizing Behaviors?

Research has tried to identify risk factors that increase the likelihood of difficulties with externalizing behavior. The relations between individual or environmental factors and externalizing behavior have been especially documented. Child-oriented and parent-oriented interventions have been designed in order to decrease externalizing behavior in preschoolers. To date, however, research has largely been compartmentalized. It is therefore not known whether child-oriented or parent-oriented intervention is more effective in reducing externalizing behavior. The aim of the current study was to answer this question by comparing two 8-week child with two 8-week parent-oriented group programs sharing a common experimental design. This was done in a pseudo-randomized trial conducted with 73 3–6-year-old children displaying clinically relevant levels of externalizing behavior who were assigned to one of the four interventions and 20 control participants who were allocated to a waiting list. The results indicate that the four programs focusing on a specific target variable, i.e., social cognition, inhibition, parental self-efficacy beliefs, or parental verbal responsiveness, are all effective in reducing externalizing behavior among preschoolers. Their effectiveness was moderated neither by their orientation toward the child or the parent nor by their content, suggesting that several effective solutions exist to improve behavioral adaptation in preschoolers. A second important highlight of this study is that, thanks to comparable effect sizes, brief focused programs appear to be a reasonable alternative to long multimodal programs, and may be more cost-effective for children and their families.     

Similarity and Helping Behavior on the Web: The Impact of the Convergence of Surnames Between a Solicitor and a Subject in a Request Made by E‐Mail1

Similarity between a solicitor and a subject traditionally enhances helping behavior. An experiment was carried out in a computer‐mediated context. Fifty students received an e‐mail containing a 40‐question survey on their food habits, which required 15 to 20 min of their time to respond. This questionnaire came from a hypothetical student of the university in which the participants were registered. In half of the cases, the surname of the solicitor, which appeared in his or her electronic address, was the same as the surname of the target. Results show that compliance to the request was significantly higher in the same‐sumame condition than in the different‐surname condition. The response delay was significantly shorter in the same‐surname condition than in control condition.     

Facing Europe: visualizing spontaneous in-group projection

Individuals perceive their own group to be more typical of a shared superordinate identity than other groups are. This in-group projection process has been demonstrated with both self-report and indirect measures. The two studies reported here extend this research to the visual level, specifically, within the domain of faces. Using an innovative reverse-correlation approach, we found that German and Portuguese participants' visual representations of European faces resembled the appearance typical for their own national identity. This effect was found even among participants who explicitly denied that one nation was more typical of Europe than the other (Study 1). Moreover, Study 2 provides experimental evidence that in-group projection is restricted to inclusive superordinate groups, as the effect was not observed for visual representations of a category ("Australian") that did not include participants' in-group. Implications for the in-group projection model, as well as for the applicability of reverse-correlation paradigms, are discussed.     

Generalized relational matching by guinea baboons (Papio papio) in two-by-two-item analogy problems

Analogical reasoning is considered the hallmark of human reasoning, but some studies have demonstrated that language- and symbol-trained chimpanzees can also reason analogically. Despite the potential adaptive value of this ability, evidence from other studies strongly suggests that other nonhuman primates do not have this capacity for analogical reasoning. In our three experiments, 6 of 29 baboons acquired the ability to perform a relational matching-to-sample (RMTS) task in which pairs of shapes composed relational displays. Five of these 6 monkeys then transferred this ability to RMTS tasks using novel exemplars of identity (elements in a pair are the same) and nonidentity (elements in a pair are different) relations. This transfer occurred even on trials in which the incorrect pair shared an element with the sample pair with which it was being compared. The baboons retained this ability 12 months later. The findings from our study of symbol-naive monkeys indicate that although language and symbol training facilitate conceptual thinking in nonhuman primates, such training is not a prerequisite for analogical reasoning.