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Natural events are often multisensory, requiring the brain to combine information from the same spatial location and timing, across different senses. The importance of temporal coincidence has led to the introduction of the temporal binding window (TBW) construct, defined as the time range within which multisensory inputs are highly likely to be perceptually bound into a single entity. Anomalies in TBWs have been linked to confused perceptual experiences and inaccurate filtering of sensory inputs coming from different environmental sources. Indeed, larger TBWs have been associated with disorders such as schizophrenia and autism and are also correlated to a higher level of subclinical traits of these conditions in the general population. Here, we tested the feasibility of using a web-based version of a classic audio-visual simultaneity judgment (SJ) task with simple flash-beep stimuli in order to measure multisensory temporal acuity and its relationship with schizotypal traits as measured in the general population. Results show that: (i) the response distribution obtained in the web-based SJ task was strongly similar to those reported by studies carried out in controlled laboratory settings, and (ii) lower multisensory temporal acuity was associated with higher schizotypal traits in the “disorganized” domains. Our findings reveal the possibility of adequately using a web-based audio-visual SJ task outside a controlled laboratory setting, available to a more diverse and representative pool of participants. These results provide additional evidence for a close relationship between lower multisensory acuity and the expression schizotypal traits in the general population.

Tracing children’s values and value-expressive behavior over a sixth-month period, we examined stability and change of values and behavior and the reciprocal relations between them. Three hundred and ten sixth-grade students in Italy completed value and value-expressive behavior questionnaires three times in three-month intervals during the scholastic year. We assessed Schwartz's (1992) higher-order values of conservation, openness to change, self-enhancement, and self-transcendence, as well as their respective expressive behaviors. Reciprocal relations over time between values and behaviors were examined using a cross-lagged longitudinal design. Results showed that values and behaviors had reciprocal longitudinal effects on one another, after the stability of the variables was taken into account (i.e., values predicted change in behaviors, but also behaviors predicted change in values). Our findings also revealed that: (1) values were more stable over time than behaviors, and (2) the longitudinal effect of values on behaviors tended to be stronger than the longitudinal effect of behaviors on values. Findings are discussed in light of the recent developmental literature on value change.

The mammalian brain is one of the organs with the highest energy demands, and mitochondria are key determinants of its functions. Here we show that the type-1 cannabinoid receptor (CB(1)) is present at the membranes of mouse neuronal mitochondria (mtCB(1)), where it directly controls cellular respiration and energy production. Through activation of mtCB(1) receptors, exogenous cannabinoids and in situ endocannabinoids decreased cyclic AMP concentration, protein kinase A activity, complex I enzymatic activity and respiration in neuronal mitochondria. In addition, intracellular CB(1) receptors and mitochondrial mechanisms contributed to endocannabinoid-dependent depolarization-induced suppression of inhibition in the hippocampus. Thus, mtCB(1) receptors directly modulate neuronal energy metabolism, revealing a new mechanism of action of G protein-coupled receptor signaling in the brain.

Background: Dermatophytoses are cosmopolitan contagious mycoses of the skin and concern a wide range of mammals, including man, and more rarely birds. These mycoses are rarely diagnosed in New World Primates. The most frequent tinea of the subhuman Primates is microsporosis due to Microsporum canis or trichophytosis by Trichophyton mentagrophytes and T. simii. The main clinical features are regular alopecia with erythema and squamosis, usually non-pruriginous although various degree of inammation may modify this typical aspect. As a consequence, an accurate clinical examination, a good differential diagnosis and laboratory analyses are required for a correct identification. Alouatta guariba are primates found from the Amazon region up to the Argentina Norwest. Due to the population development and expansion of the urban perimeters these animals are loosing their space in their own natural habitat and being exposed to more closed relationship with domestic animals and humans. This report contains five cases of dermatophytoses caused by Microsporum canis in Alouatta sp., which were treated in a private clinic in Porto Alegre, RS, Brazil. Case: Five females of Alouatta guariba with aged between 2 and 8 months old were admitted in a private veterinary clinic (Toca dos Bichos, Porto Alegre). Each of them had different injuries (electric chock, death of the parent due gun shot, aggression between families and dog bite) and were admitted in different dates. All five primates were presented with intense pruritus after 7 or 10 days of admission. At physical examination lesions characteristic of dermatophytoses were found. To establish a definitive diagnosis it was collected fur and skin and the material was send to the Mycology Laboratory of the Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil. The fungic culture was positive for Microsporum canis. The treatment established was fluconazole, 18 mg/kg/day PO, mixed in smashed bananas. After two weeks of treatment, a sensitive clinic improvement was seen in all primates, characterized by diminishing of pruritus and alopecic areas. At 30 days of treatment the animals had no clinical signs of lesions and had their fur completely re-grown. The medication was administered for more 15 days, totalizing 45 days of treatment, at which time the animals were considered cured. The primates were monitored for more 30 days after the last dose of fluconazole. Discussion: Case reports on the isolation of Microsporum canis in non-human primates, mainly in New World Primates, are very rare in the Brazilian literature. It is necessary more cohesive approach to nonhuman primate (NHP) dermatology, without relying on assumptions that it is similar to other veterinary disease. Mycological culture remains the gold standard for the diagnosis of animal dermatophytosis and the only method for the phenotypic identication of dermatophyte species. The fluconazole treatment proved to be highly effective, as the animals were all cured and there was no side effects related. This case report proves the importance of a correct mycological diagnostic in free-range animals as an effective treatment in Alouatta guariba.

Abnormally high spiking activity can damage neurons. Signaling systems to protect neurons from the consequences of abnormal discharge activity have been postulated. We generated conditional mutant mice that lack expression of the cannabinoid receptor type 1 in principal forebrain neurons but not in adjacent inhibitory interneurons. In mutant mice,the excitotoxin kainic acid (KA) induced excessive seizures in vivo. The threshold to KA-induced neuronal excitation in vitro was severely reduced in hippocampal pyramidal neurons of mutants. KA administration rapidly raised hippocampal levels of anandamide and induced protective mechanisms in wild-type principal hippocampal neurons. These protective mechanisms could not be triggered in mutant mice. The endogenous cannabinoid system thus provides on-demand protection against acute excitotoxicity in central nervous system neurons.

Acquisition and storage of aversive memories is one of the basic principles of central nervous systems throughout the animal kingdom. In the absence of reinforcement, the resulting behavioural response will gradually diminish to be finally extinct. Despite the importance of extinction, its cellular mechanisms are largely unknown. The cannabinoid receptor 1 (CB1) and endocannabinoids are present in memory-related brain areas and modulate memory. Here we show that the endogenous cannabinoid system has a central function in extinction of aversive memories. CB1- deficient mice showed strongly impaired short-term and long-term extinction in auditory fear-conditioning tests, with unaffected memory acquisition and consolidation. Treatment of wild-type mice with the CB1 antagonist SR141716A mimicked the phenotype of CB1-deficient mice, revealing that CB1 is required at the moment of memory extinction. Consistently, tone presentation during extinction trials resulted in elevated levels of endocannabinoids in the basolateral amygdala complex, a region known to control extinction of aversive memories. In the basolateral amygdala, endocannabinoids and CB1 were crucially involved in long-term depression of GABA (gamma-aminobutyric acid)-mediated inhibitory currents. We propose that endocannabinoids facilitate extinction of aversive memories through their selective inhibitory effects on local inhibitory networks in the amygdala.