Differences in problem-solving between canid populations: Do domestication and lifetime experience affect persistence?

Past research has suggested that a variety of factors, phylogenetic and ontogenetic, play a role in how canines behave during problem-solving tasks and the degree to which the presence of a human influences their problem-solving behaviour. While comparisons between socialized wolves and domestic dogs have commonly been used to tease apart these predictive factors, in many cases a single dog population, often pets, have been used for these comparisons. Less is understood about how different populations of dogs may behave when compared with wolves, or with each other, during an independent problem-solving task. This experiment compared the independent persistence of four populations of canines (two groups of pet domestic dogs, a group of free-ranging domestic dogs, and human-socialized wolves) on an independent problem-solving task in the presence of an on looking human. Results showed that wolves persisted the most at the task while free-ranging dogs persisted the least. Free-ranging dogs gazed at the human experimenter for the longest durations during the task. While further research is needed to understand why these differences exist, this study demonstrates that dogs, even those living outside human homes as scavengers, show comparatively low levels of persistence when confronted with a solvable task in the presence of a human as well as significantly greater duration of human-directed gaze when compared with wolves.     

Practice makes perfect: familiarity of task determines success in solvable tasks for free-ranging dogs (<Emphasis Type="Italic">Canis lupus familiaris</Emphasis>)

Domestic dogs’ (Canis lupus familiaris) socio-cognitive faculties have made them highly sensitive to human social cues. While dogs often excel at understanding human communicative gestures, they perform comparatively poorly in problem-solving and physical reasoning tasks. This difference in their behaviour could be due to the lifestyle and intense socialization, where problem solving and physical cognition are less important than social cognition. Free-ranging dogs live in human-dominated environments, not under human supervision and are less socialized. Being scavengers, they often encounter challenges where problem solving is required in order to get access to food. We tested Indian street dogs in familiar and unfamiliar independent solvable tasks and quantified their persistence and dependence on a novel human experimenter, in addition to their success in solving a task. Our results indicate that free-ranging dogs succeeded and persisted more in the familiar task as compared to the unfamiliar one. They showed negligible amount of human dependence in the familiar task, but showed prolonged gazing and considerable begging behaviour to the human experimenter in the context of the unfamiliar task. Cognitive abilities of free-ranging dogs thus play a pivotal role in determining task-associated behaviours based on familiarity. In addition to that, these dogs inherently tend to socialize with and depend on humans, even if they are strangers. Our results also illustrate free-ranging dogs’ low competence at physical cognitive tasks.     

Predictive Validity of Adult Attachment Measures in Relation to Emotion Regulation Behaviors in Marital Interactions

This study examined the predictive validity of 2 assessment approaches to adult attachment in relation to emotion regulation behaviors during marital conflict interactions. Both partners of 40 couples completed the Adult Attachment Style self-report (AAS; C. Hazan & P. Shaver, 1987), the Adult Attachment Questionnaire (AAQ; J. A. Simpson, 1990), the Adult Attachment Interview (AAI; C. George, N. Kaplan, & M. Main, 1985), and a videotaped interaction during which the partners engaged in a problem-solving discussion. The discussions were coded by means of the Interactional Dimensions Coding System (IDCS; D. Julien, H. J. Markman, & K. M. Lindhal, 1989). Results showed that AAI classification predicted proactive emotion regulation behaviors, whereas the AAS and the AAQ did not. Issues concerning the predictive validity of current measures of adult attachment are discussed.     

Parenting and toddler self-regulation in low-income families: What does sleep have to do with it?

Toddlerhood is a sensitive period in the development of self-regulation, a set of adaptive skills that are fundamental to mental health and partly shaped by parenting. Healthy sleep is known to be critical for self-regulation; yet, the degree to which child sleep alters interactive child–parent processes remains understudied. This study examines associations between observed parenting and toddler self-regulation, with toddler sleep as a moderator of this association. Toddlers in low-income families (N = 171) and their mothers were videotaped during free play and a self-regulation challenge task; videos were coded for mothers’ behavior and affect (free play) and toddlers’ self-regulation (challenge task). Mothers reported their child's nighttime sleep duration via questionnaire. Results revealed significant Sleep × Maternal Negative Affect and Sleep × Maternal Negative Control interactions. Children who did not experience negative parenting had good self-regulation regardless of their nighttime sleep duration. For children who did experience negative parenting, self-regulation was intact among those who obtained more nighttime sleep, but significantly poorer among children who were getting less nighttime sleep. Thus, among children who were reported to obtain less nighttime sleep, there were more robust associations between negative parenting and poorer self-regulation than among toddlers who were reported to obtain more sleep.     

The behavioral effects of enriched housing are not altered by serotonin depletion but enrichment alters hippocampal neurochemistry

To assess a possible role for serotonin in the mediation of the behavioral changes induced by enriched housing conditions (EC), adult female Long-Evans rats sustaining a serotonin depletion (150 microg of 5,7-dihydroxytryptamine, icv) and sham-operated rats were housed postoperatively for 30 days in enriched (12 rats/large cage containing various objects) or standard housing conditions (2 rats/standard laboratory cage). Thereafter, anxiety responses (elevated plus-maze), locomotor activity (in the home-cage), sensori-motor capabilities (beam-walking task), and spatial memory (eight-arm radial maze) were assessed. Monoamine levels were subsequently measured in the frontoparietal cortex and the hippocampus. Overall, EC reduced anxiety-related responses, enhanced sensori-motor performance and improved the memory span in the initial stage of the spatial memory task. Despite a substantial reduction of serotonergic markers in the hippocampus (82%) and the cortex (74%), these positive effects of EC were not altered by the lesion. EC reduced the serotonin levels in the ventral hippocampus (particularly in unlesioned rats: -23%), increased serotonin turnover in the entire hippocampus (particularly in lesioned rats: +36%) and augmented the norepinephrine levels in the dorsal hippocampus (+68% in unlesioned and +49% in lesioned rats); no such alterations were found in the frontoparietal cortex. Our data suggest that an intact serotonergic system is not a prerequisite for the induction of positive behavioral effects by EC. The neurochemical changes found in the hippocampus of EC rats, however, show that the monoaminergic innervation of the hippocampus is a target of EC.     

Predictive influence of phonological processing, morphological/syntactic skill, and naming speed on spelling performance

This paper focuses on the predictive influence of phonological awareness, morphological/syntactic skill, and naming speed on spelling. The retrospective study correlated spelling performance in a group of 199 French-speaking children at the end of grade 2 with earlier capacities for phonemic manipulation, morphological/syntactic correction, and naming speed, assessed at the end of grade 1. The results are consistent with an integrative model that challenges the unitary phonological disorder hypothesis and confirmed that in French, as in other languages, naming speed is an independent predictor of reading performance.     

Processes of inference, schizotypal thinking, and obsessive-compulsive behaviour in a normal sample

Previous research has shown inferential confusion as measured by the Inferential Confusion Questionnaire to be related to obsessive-compulsive symptoms. A total of 108 participants (41 men and 66 women) from a normal population in The Netherlands (M age = 46 yr., SD = 15.5) completed a package of questionnaires measuring inferential confusion, schizotypal symptoms, and obsessive-compulsive behaviour. As expected, scores for both inferential confusion and schizotypal symptoms were significantly related to those for obsessive-compulsive behaviour. In addition, analysis showed that inferential confusion and schizotypal symptoms shared common variance, but both predicted an independent portion of the variance in obsessive-compulsive behaviour while controlling for neuroticism. The present results call for further inquiry into the role of inferential confusion and schizotypal thinking in obsessive-compulsive behaviour.     

Pitch Cues for the Recognition of Yes-No Questions in French

Linguistic studies of the intonation of Yes–No questions in French show that, in questions containing more than two stress groups, interrogative intonation is characterized by a sequence of lowered pitches or downstepped tones which precede the final rise. The gating paradigm was used here to determine whether subjects listening to French NP utterances containing three stress groups could indicate whether the utterance was an statement or a question before the final rise was heard. Although the task was difficult, findings indicate that listeners can in fact to a certain extent, recognize with mid confidence ratings, the intonational device of a question while they were hearing the downstepped tones preceding the final rise.