We report an experimental investigation into whether domesticated dogs display contagious yawning. Fifteen dogs were shown video clips of (1) humans and (2) dogs displaying yawns and open-mouth expressions (not yawns) to investigate whether dogs showed contagious yawning to either of these social stimuli. Only one dog performed significantly more yawns during or shortly after viewing yawning videos than to the open-mouth videos, and most of these yawns occurred to the human videos. No dogs showed significantly more yawning to the open-mouth videos (human or dog). The percentage of dogs showing contagious yawning was less than chimpanzees and humans showing this behavior, and considerably less than a recently published report investigating this behavior in dogs (Joly-Mascheroni et al. in Biol Lett 4:446-448, 2008).

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The diet of capuchin monkeys consists largely of fruits, but these monkeys commonly prey upon insects and other invertebrates as well as vertebrates such as lizards, birds, and fish. Capturing small fast-moving prey requires the ability to process complex visuospatial information such as motion detection, shape, and pursuit. Here we report the results of an experimental investigation into whether capuchins display sex differences in prey capture efficiency, and whether these differences are associated with the morphology of regions of the corpus callosum (CC) involved in visuospatial ability. We examined the prey capture behavior of seven capuchin subjects (four female, three male) in the laboratory by providing subjects opportunities to fish. Additionally, we obtained structural magnetic resonance images from these subjects to determine if spatial-ability was related to CC anatomy. Over 30 fishing trials, we recorded the number of prey capture attempts, success rate in capturing fish, and hand techniques used in these attempts. Males were significantly faster and more successful than females at capturing prey. In addition, males had smaller total CC:brain ratios than females. Males displayed a left hand bias, as well as significant unimanual usage, whereas females displayed no significant preference for hand usage. Individual capture times were correlated with total CC:brain ratio. Taken together, our results suggest a relationship between prey capture efficiency, sex, and the degree of brain lateralization.

The basal ganglia are subcortical structures involved in the planning, initiation and regulation of movement as well as a variety of non-motor, cognitive and affective functions. Capuchin monkeys share several important characteristics of development with humans, including a prolonged infancy and juvenile period, a long lifespan, and complex manipulative abilities. This makes capuchins important comparative models for understanding age-related neuroanatomical changes in these structures. Here we report developmental volumetric data on the three subdivisions of the basal ganglia, the caudate, putamen and globus pallidus in brown capuchin monkeys (Cebus apella). Based on a cross-sectional sample, we describe brain development in 28 brown capuchin monkeys (male n = 17, female n = 11; age range = 2 months -20 years) using high-resolution structural MRI. We found that the raw volumes of the putamen and caudate varied significantly with age, decreasing in volume from birth through early adulthood. Notably, developmental changes did not differ between sexes. Because these observed developmental patterns are similar to humans, our results suggest that capuchin monkeys may be useful animal models for investigating neurodevelopmental disorders of the basal ganglia.

Aslib Library holds a collection of thesauri, subject headings and classification schemes which are used to answer members' enquiries about the existence of schemes for particular subject fields and many of which are available on loan for two weeks. Our policy is to acquire all significant English language publications and bilingual or multilingual items with English as one of the languages.

SIRT1 is a nicotinamide adenine dinucleotide (NAD+)-dependent deacetylase which regulates many physiological and pathological processes. Over the past decade, increasing attention has been paid to the wide distribution of SIRT1 in the eye and its important role in eye development. The short review summarized the most recent research in the study of SIRT1 related to eye development and its distribution in eye.

Neural cell adhesion molecule (NCAM) is associated with polysialic acid (PSA), and its function is highly dependent on the extent of polysialylation through the activity of two polysialyltransferases, sialyltransferase-X (STX) and polysialyltransferase (PST). PSA-NCAM plays an important role in synaptic plasticity in the hippocampus. The involvement of STX and PST during mnesic processes was assessed in the adult rat hippocampus. We investigated whether different levels in learning and memory using an olfactory associative task influenced STX and PST gene expression in the hippocampus using semiquantitative transcription-polymerase chain reaction. Then, NCAM polysialylation and cell proliferation were quantified in the dentate gyrus of a "Learning and Memory" group using immunohistochemistry. We found that only the expression level of PST mRNA increased with learning performance and returned to an initial level when learned associations were consolidated in long-term memory, while STX mRNA levels remained unchanged. This phenomenon was accompanied by an increase in PSA on NCAM but not by cell proliferation in the dentate gyrus. Our results suggest a different involvement for STX and PST in neural plasticity: while STX is probably involved in the proliferation of neural progenitor cells, PST could play a key role in synaptic plasticity of mature neural networks. The expression of the STX and PST genes could, therefore, be useful markers of neurobiological plasticity in the brain, allowing to follow chronological events in limbic and cortical structures related first to learning and memory processes (for PST) and, second, to adult neurogenesis processes (for STX).

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