Behavioral and developmental consequences of early rearing experience for captive giant pandas (Ailuropoda melanoleuca)

Mother-reared (MR) and peer-reared (PR) captive giant panda (Ailuropoda melanoleuca) cubs were compared to evaluate the effects of early removal from mother on behavioral development. Males and females and twins and singletons were compared to assess the effects of social setting on behavioral development. Subjects included 2 PR females, 3 MR females, 3 MR males, and 3 mothers. MR cubs spent more time manipulating bamboo and fell more often than PR cubs. PR cubs spent more time inactive. Male cubs directed more playful behavior at their mothers. Twins spent more time play fighting with their mothers than with their siblings. The results suggest that peer-rearing does not provide young pandas with the same level of social stimulation as mother-rearing.     

Perceptions and implications of received spousal care: evidence from the Caregiver Health Effects Study

The experiences of older care recipients have received far less theoretical and empirical attention than those of their family caregivers. In this study of 91 care recipients, the authors assessed perceptions of the amount, timing, and manner of spousal assistance; the amount of strain experienced from receiving care; and psychological well-being. Although female care recipients were more likely to report dissatisfaction with the manner in which assistance was provided, there were few gender differences in perceptions of care overall. In a stringent test of the hypothesis that perceived quality of spousal care affects recipient well-being, the authors found that poorer quality of care was related to increased depressive symptoms and a decreased sense of mastery 1 year later. These longitudinal effects were independent of the recipient's physical disability, marital quality, and care-receiving strain as well as the caregiver's well-being. These findings argue for a comprehensive assessment of the care-receiving experience that includes both care-recipient and caregiver perspectives.     

An enquiry into the process of categorization of pictures and words

This paper reports a series of experiments conducted to study the categorization of pictures and words. Whereas some studies reported in the past have found a picture advantage in categorization, other studies have yielded no differences between pictures and words. This paper used an experimental paradigm designed to overcome some methodological problems to examine picture-word categorization. The results of one experiment were consistent with an advantage for pictures in categorization. To identify the source of the picture advantage in categorization, two more experiments were conducted. Findings suggest that semantic relatedness may play an important role in the categorization of both pictures and words. We explain these findings by suggesting that pictures simultaneously access both their concept and visually salient features whereas words may initially access their concept and may subsequently activate features. Therefore, pictures have an advantage in categorization by offering multiple routes to semantic processing.     

Explicit and implicit memory for rotating objects

Although both the object and the observer often move in natural environments, the effect of motion on visual object recognition ha not been well documented. The authors examined the effect of a reversal in the direction of rotation on both explicit and implicit memory for novel, 3-dimensional objects. Participants viewed a series of continuously rotating objects and later made either an old-new recognition judgment or a symmetric-asymmetric decision. For both tasks, memory for rotating objects was impaired when the direction of rotation was reversed at test. These results demonstrate that dynamic information can play a role in visual object recognition and suggest that object representations can encode spatiotemporal information.     

Learning the unlearnable: the role of missing evidence

Syntactic knowledge is widely held to be partially innate, rather than learned. In a classic example, it is sometimes argued that children know the proper use of anaphoric one, although that knowledge could not have been learned from experience. Lidz et al. [Lidz, J., Waxman, S., & Freedman, J. (2003). What infants know about syntax but couldn't have learned: Experimental evidence for syntactic structure at 18 months. Cognition, 89, B65-B73.] pursue this argument, and present corpus and experimental evidence that appears to support it; they conclude that specific aspects of this knowledge must be innate. We demonstrate, contra Lidz et al., that this knowledge may in fact be acquired from the input, through a simple Bayesian learning procedure. The learning procedure succeeds because it is sensitive to the absence of particular input patterns--an aspect of learning that is apparently overlooked by Lidz et al. More generally, we suggest that a prominent form of the "argument from poverty of the stimulus" suffers from the same oversight, and is as a result logically unsound.     

The characteristics and correlates of fantasy in school-age children: imaginary companions, impersonation, and social understanding

Past research with 152 preschoolers found that having an imaginary companion or impersonating an imaginary character was positively correlated with theory of mind performance. Three years later, 100 children from this study were retested to assess the developmental course of play with imaginary companions and impersonation of imaginary characters and how these types of role play were related to emotion understanding, self-perception, and personality. The results showed that school-age children interact with imaginary companions and impersonate imaginary characters as much as preschoolers. Overall, 65% of children up to the age of 7 had imaginary companions at some point during their lives. School-age children who did not impersonate scored lower on emotion understanding. Theory of mind at age 4 predicted emotion understanding 3 years later.     

PTSD arousal and depression symptoms associated with increased right-sided parietal EEG asymmetry

Researchers have proposed that depression and particular types of anxiety are associated with unique patterns of regional brain activation. The authors examined the relationship among posttraumatic stress disorder (PTSD), anxiety, and depressive symptoms and frontal, temporal, and parietal EEG alpha asymmetry in female Vietnam War nurse veterans. The results indicate that PTSD arousal symptoms are associated with increased right-sided parietal activation. However, the combination of arousal, depression, and their interaction explain more than twice the variance in parietal asymmetry compared with arousal alone. The results support the contention that the association between anxiety and right-sided posterior activation is specific to the anxious arousal subtype. These findings underscore the importance of isolating, both theoretically and statistically, emotional subcomponents in studies of regional brain activation.     

Child Impulsiveness—Inattention, Early Peer Experiences, and the Development of Early Onset Conduct Problems

The conjoint influence of child impulsiveness-inattention (I/I) and peer relationships on growth trajectories of conduct problems was assessed in a community sample of 267 boys and girls. I/I reliably predicted teacher- and parent-reported conduct problems at kindergarten entry and growth in those problems over the next 2 years for boys and girls. The relation of boys' I/I to conduct problems was mediated, in part, by peer rejection and involvement in coercive exchanges with peers. The relation of girls' I/I to conduct problems was less clearly mediated by peer processes, but peer difficulties had additive effects. The impact of peer relationships on trajectories of conduct problems was apparent to parents as well as to teachers. Although I/I increments risk for early and persisting conduct problems in concert with poor peer relationships, it does so in complex and gender-specific ways.