Handedness Influences Intermanual Transfer in Chimpanzees (\u3cem\u3ePan troglodytes\u3c/em\u3e) But Not Rhesus Monkeys (\u3cem\u3eMacaca mulatta\u3c/em\u3e)

Intermanual transfer refers to an effect whereby training one hand to perform a motor task improves performance in the opposite untrained hand. We tested the hypothesis that handedness facilitates intermanual transfer in two nonhuman primate species: rhesus monkeys (N = 13) and chimpanzees (N = 52). Subjects were grouped into one of four conditions: (1) left-handers trained with the left (dominant) hand; (2) left-handers trained with the right (non-dominant) hand; (3) right-handers trained with the left (non-dominant) hand; and (4) right-handers trained with the right (dominant) hand. Intermanual transfer was measured using a task where subjects removed a Life Savers® candy (monkeys) or a washer (chimpanzees) from metal shapes. Transfer was measured with latency by comparing the average time taken to solve the task in the first session with the trained hand compared to the first session with the untrained hand. Hypotheses and predictions were derived from three models of transfer: access: benefit training with non-dominant hand; proficiency: benefit training with dominant hand; and cross-activation: benefit irrespective of trained hand. Intermanual transfer (i.e., shorter latency in untrained hand) occurred regardless of whether monkeys trained with the dominant hand or non-dominant hand, supporting the cross-activation model. However, transfer was only observed in chimpanzees that trained with the dominant hand. When handedness groups were examined separately, the transfer effect was only significant for right-handed chimpanzees, partially supporting the proficiency model. Findings may be related to neurophysiological differences in motor control as well as differences in handedness patterning between rhesus monkeys and chimpanzees

Neural Systems Underlying RDoC Social Constructs: An Activation Likelihood Estimation Meta-Analysis

Neuroscientists have sought to identify the underlying neural systems supporting social processing that allow interaction and communication, forming social relationships, and navigating the social world. Through the use of NIMH’s Research Domain Criteria (RDoC) framework, we evaluated consensus among studies that examined brain activity during social tasks to elucidate regions comprising the “social brain”. We examined convergence across tasks corresponding to the four RDoC social constructs, including Affiliation and Attachment, Social Communication, Perception and Understanding of Self, and Perception and Understanding of Others. We performed a series of coordinate-based meta-analyses using the activation likelihood estimate (ALE) method. Meta-analysis was performed on whole-brain coordinates reported from 864 fMRI contrasts using the NiMARE Python package, revealing convergence in medial prefrontal cortex, anterior cingulate cortex, posterior cingulate cortex, temporoparietal junction, bilateral insula, amygdala, fusiform gyrus, precuneus, and thalamus. Additionally, four separate RDoC-based meta-analyses revealed differential convergence associated with the four social constructs. These outcomes highlight the neural support underlying these social constructs and inform future research on alterations among neurotypical and atypical populations

Behavior and psychological functioning of young children of HIV-positive mothers in South Africa

Adults with HIV are living longer due to earlier diagnosis and increased access to antiretroviral medications. Therefore, fewer young children are being orphaned and instead, are being cared for by parents who know they are HIV positive, although they may be asymptomatic. Presently, it is unclear whether the psychological functioning of these young children is likely to be affected or, alternatively, whether it is only when a mother is ill, that children suffer adverse effects. We, thus, aimed to compare the behavior and psychological functioning of young children (aged 6 10 years) of HIV-positive and HIV-negative mothers. We also aimed to examine the association between HIV status disclosure and child outcomes. This study uses cross-sectional data from the baseline assessment of a randomized controlled trial conducted in Tshwane, South Africa. Participants (n 509) and their children were recruited from area health clinics. Among the 395 mothers with HIV, 42% reported symptoms of HIV disease. Multivariate linear regression models suggested that after adjusting for sociodemographic characteristics, children of HIV-positive mothers had significantly greater externalizing behaviors than children of HIV-negative mothers. Importantly, children whose mothers were symptomatic had greater internalizing and externalizing behaviors compared with children of HIV-negative mothers, but this was not true for children of asymptomatic mothers. Additionally, among children of HIV-positive mothers, those who had been told their mothers were sick compared with children who had been told nothing had less internalizing and externalizing behaviors and improved daily living skills. This study, therefore, provides evidence that maternal HIV disease can affect the behaviors of young children in South Africa but, importantly, only when the mothers are symptomatic from their disease. Furthermore, results suggest that disclosure of maternal illness but not HIV status was associated with improved behavior and psychological functioning among young children.National Institute of Mental Health (Grant 5R01HD057834)http://www.tandfonline.com/loi/caic20hb201

The larva of Nevermannia dorcatomoides Fisher with comments on the classification of the Anobiidae according to their larvae (Coleoptera: Anobiidae)

Volume: 29Start Page: 51End Page: 6

Network Analysis as a Tool to Understand Social Development in Spider Monkeys

The emerging field of network science has demonstrated that an individual\u27s connectedness within their social network has cascading effects to other dimensions of life. Like humans, spider monkeys live in societies with high fission–fusion dynamics, and are remarkably social. Social network analysis (SNA) is a powerful tool for quantifying connections that may vary as a function of initiating or receiving social behaviors, which has been described as shifting social roles. In primatology, the SNA literature is dominated by work in catarrhines, and has yet to be applied to the study of development in a platyrrhine model. Here, SNA was utilized in combination with R-Index social role calculation to characterize social interaction patterns in juvenile and adult Colombian spider monkeys (Ateles fusciceps rufiventris). Connections were examined across five behaviors: embrace, face-embrace, grooming, agonism, and tail-wrapping from 186 hr of observation and four network metrics. Mann–Whitney U tests were utilized to determine differences between adult and juvenile social network patterns for each behavior. Face-embrace emerged as the behavior with different network patterns for adults and juveniles for every network metric. With regard to social role, juveniles were receivers, not initiators, for embrace, face-embrace, and grooming (ps \u3c .05). Network and social role differences are discussed in light of social development and aspects of the different behaviors