Diet and seed dispersal of bearded capuchin monkeys (Sapajus libidinosus) in Brasilia National Park.

The dietary ecology of a species can provide information on habitat requirements, food resources, and trophic interactions, important to guide conservation efforts of wildlife populations in endangered habitats. In this study, we investigated the dietary ecology of bearded capuchin monkeys (Sapajus libidinosus) in Brasilia National Park, in the endangered Cerrado biome of central Brazil. To obtain diet composition and evaluate the role of these primates as seed dispersers of local tree species, fecal sample collections and feeding observations were performed for a 7-month period. To determine whether seeds germinated better after passing through a primate gut, we conducted germination trials with (i) pulped seeds from trees, (ii) depulped seeds from trees, (iii) seeds from feces planted with feces, and (iv) seeds from feces planted without feces. During experimental procedures, 7308 seeds from 8 families and 10 species were planted. We found that S. libidinosus spent more time feeding on fruits than on any other food item and the diet consisted of 33 plant species from 21 families. However, 20% of their diet consisted of anthropic food. Most seeds planted with feces germinated faster compared to seeds in other experimental treatments, suggesting that passing through the gut and being deposited with fecal material is advantageous. The bearded capuchins also defecated many medium- (5 species) and large-sized (2 species) seeds that may be inaccessible to smaller arboreal frugivores. The results obtained emphasize the important role of bearded capuchins as seed dispersers for the maintenance and conservation of the endangered Cerrado biome.

The importance on the use of active methods when teaching human morphophysiology.

Traditional didactic methods have not been successful in promoting independent and reflective students. Thus new teaching techniques are essential to optimize the way students learn. This study aimed to evaluate the perception of students, from the Faculty of Ceilandia, University of Brasília (FCE/UnB), about the active method "inverted class," which has as its primary characteristic to stimulate the student to study and research the contents before the theoretical classes or explanation of the teacher. To this end, 64 students of the summer course participated in the Flipped Classroom and later evaluated the discipline method. Initially, they received a script with clinical questions about the class's content, which should be discussed and answered about the basic, clinical, and practical application concepts. To evaluate the didactic method applied, on the last day of class, the summer class students were invited to answer a survey about satisfaction when learning the contents. For 98% of the students, the teaching method used was approved. It is also emphasized that this class had 48 repeating students, unmotivated with the course because, for many, they declared themselves unable to be approved. Given the success of the method, we decided to apply it throughout 2018, so the method was applied to over 180 students of FCE/UnB health courses. In short, it is considered that the results presented here to support other studies that highlight the need for changes in traditional teaching methods, which is a didactic option in undergraduate courses.

Analysis of palmprints and soleprints of black-tufted marmosets (Callithrix penicillata): are there similarities to humans?

Friction ridges are important and unique biometric features that have been studied in fingerprint science since antiquity and used for human identification. This study aimed to analyze palmprints and soleprints of Callithrix penicillata, including the description of flexion creases, regions, minutiae classification, and delta counting, in order to evaluate the uniqueness of these data and feasibility of using this information as an identification method. Palmprints and footprints were collected using commercial fingerprint ink on A4 size paper. Following image digitalization using the GIMP (2.10.14) image editing program, regions and flexion creases were identified. A total of 600 minutiae were classified in females (288 palms and 312 soles) and 732 in males (360 palms and 372 soles), and all deltas were counted. It was possible to identify three main inconstant flexion creases, in both palmprints and soleprints, with different distribution and orientation when compared to those in humans. Less variety in the types of minutiae and differences in the distribution of deltas were found when compared to human studies. In addition, the hypothesis of non-coincident characteristics in each sample was confirmed.

Bearded capuchin monkeys as a model for Alzheimer's disease.

The absence of a natural animal model is one of the main challenges in Alzheimer's disease research. Despite the challenges of using nonhuman primates in studies, these animals can bridge mouse models and humans, as nonhuman primates are phylogenetically closer to humans and can spontaneously develop AD-type pathology. The capuchin monkey, a New World primate, has recently attracted attention due to its skill in creating and using instruments. We analyzed one capuchin brain using structural 7 T MRI and performed a neuropathological evaluation of three animals. Alzheimer-type pathology was found in the two of the capuchins. Widespread ß-amyloid pathology was observed, mainly in focal deposits with variable morphology and a high density of mature plaques. Notably, plaque-associated dystrophic neurites associated with disruption of axonal transport and early cytoskeletal alteration were frequently found. Unlike in other species of New World monkeys, cerebral arterial angiopathy was not the predominant form of ß-amyloid pathology. Additionally, abnormal aggregates of hyperphosphorylated tau, resembling neurofibrillary pathology, were observed in the temporal and frontal cortex. Astrocyte hypertrophy surrounding plaques was found, suggesting a neuroinflammatory response. These findings indicate that aged capuchin monkeys can spontaneously develop Alzheimer-type pathology, indicating that they may be an advantageous animal model for research in Alzheimer's disease.

Bifidobacteria define gut microbiome profiles of golden lion tamarin (Leontopithecus rosalia) and marmoset (Callithrix sp.) metagenomic shotgun pools.

Gut microbiome disruptions may lead to adverse effects on wildlife fitness and viability, thus maintaining host microbiota biodiversity needs to become an integral part of wildlife conservation. The highly-endangered callitrichid golden lion tamarin (GLT-Leontopithecus rosalia) is a rare conservation success, but allochthonous callitrichid marmosets (Callithrix) serve as principle ecological GLT threats. However, incorporation of microbiome approaches to GLT conservation is impeded by limited gut microbiome studies of Brazilian primates. Here, we carried out analysis of gut metagenomic pools from 114 individuals of wild and captive GLTs and marmosets. More specifically, we analyzed the bacterial component of ultra filtered samples originally collected as part of a virome profiling study. The major findings of this study are consistent with previous studies in showing that Bifidobacterium, a bacterial species important for the metabolism of tree gums consumed by callitrichids, is an important component of the callitrichid gut microbiome - although GTLs and marmosets were enriched for different species of Bifidobacterium. Additionally, the composition of GLT and marmoset gut microbiota is sensitive to host environmental factors. Overall, our data expand baseline gut microbiome data for callitrichids to allow for the development of new tools to improve their management and conservation.

Gastrointestinal Parasites Affecting Non-Human Primates That Are Kept Ex Situ and Their Handlers in Different Brazilian Institutions: Diagnosis and Analysis of Risk Factors.

AIM: Determining gastrointestinal parasites' frequency in non-human primates (NHPs) and handlers in different Brazilian institutions, and associate it with management information. METHODS: Different institutions in São Paulo (A), Brasília (B), Rio de Janeiro (C), Pará (D) and Santa Catarina (E) were included in the study. Fecal samples were processed by using coproparasitological techniques; information about NHP handling and professionals' routine were collected through the use of questionnaires. RESULTS: In total, 33.1% of 511 NHP samples were positive for parasites; the Entamoebidae Group and Strongyloides sp.-compatible eggs were the most detected protozoa and helminths, respectively. The Entamoebidae Group was mainly diagnosed in Alouatta from Institutions E and D, and was also the only parasite detected in handlers. Strongyloides-compatible eggs were mostly evident in fecal samples collected from Cebidae from Institutions B and D. Some risk factors associated with parasite infection were a high number of animals in the same enclosure and their use for research protocol purposes, whereas quarantine, a post-infection vacant period in enclosures and antiparasitic supply were categorized as protective factors against these agents' infection. CONCLUSIONS: Parasites showing different transmission routes but concomitantly circulating in NHP institutions located in different Brazilian regions were identified in the current study, with an emphasis on those presenting zoonotic potential.

Bearded capuchin monkey as a model for Alzheimer's disease research.

The absence of a natural animal model is one of the main challenges in Alzheimer's disease research. Despite the challenges of using non-human primates in studies, they can bridge mouse models and humans, as non-human primates are phylogenetically close to humans and can spontaneously develop AD-type pathology. The capuchin monkey, a New World primate, has recently attracted attention due to its skill in creating and using instruments. We analyzed three capuchin brains using structural 7T MRI and neuropathological evaluation. Alzheimer-type pathology was found in one case. Widespread ß-amyloid pathology mainly in the form of focal deposits with variable morphology and high density of mature plaques. Noteworthy, plaque-associated dystrophic neurites, associated with disrupted of axonal transport and early cytoskeletal alteration, were frequently found. Unlike other species of New World monkeys, cerebral arterial angiopathy was not the predominant form of ß-amyloid pathology. Additionally, abnormal aggregates of hyperphosphorylated tau, resembling neurofibrillary pathology, were observed in the temporal and frontal cortex. Besides, astrocyte hypertrophy surrounding plaques was found, suggesting a neuroinflammatory response. Aged capuchin monkeys can spontaneously develop Alzheimer-type pathology, indicating that they may be an advantageous animal model for research in Alzheimer's disease.

Parkinson's Disease-Cognitive Rating Scale (PD-CRS): Normative Data and Mild Cognitive Impairment Assessment in Brazil.

Background: The Parkinson's Disease-Cognitive Rating Scale (PD-CRS) assesses posterior-cortical and frontal-subcortical cognitive functioning and distinguishes mild cognitive impairment in Parkinson's disease (PD-MCI); however, it was not evaluated in Brazil. Objectives: To investigate PD-CRS's reliability, validity, normative data, and accuracy for PD-MCI screening in Brazil. Methods: The effects of age, education, and sex on PD-CRS scores were explored. The instrument was tested in 714 individuals (53% female, 21-94 years), with a broad range of education and no neurodegenerative disorder. Trail Making, Consonant Trigrams, Five-Point, and semantic fluency tests were administered for comparison. A second study enrolled patients with PD and intact cognition (n = 44, 59.75 ± 10.79 years) and with PD-MCI (n = 25, 65.76 ± 10.33 years) to investigate criterion validity. PD-CRS subtests were compared with the Cambridge Automated Neuropsychological Battery memory and executive tasks. Results: PD-CRS was unidimensional and reliable (McDonald's ω = 0.83). Using robust multiple regressions, age, and education predicted the total and derived scores in the normative sample. At the 85-point cutoff, PD-MCI was detected with 68% sensitivity and 86% specificity (area under the curve = 0.870). PD-CRS scores strongly correlated with executive and verbal/visual memory tests in both normative and clinical samples. Conclusions: This study investigated the applicability of PD-CRS in the Brazilian context. The scale seems helpful in screening for PD-MCI, with adequate internal consistency and construct validity. The PD-CRS variance is influenced by age and educational level, a critical issue for cognitive testing in countries with educational and cultural heterogeneity.

Estrogen, cognitive functions and emotion: an overview on humans, non-human primates and rodents in reproductive years.

Accumulating evidence has highlighted a number of important, global issues regarding the influence of estrogen on emotion and cognitive functions,including learning and memory processes, both in animal models and humans. The influence of estrogen on cognition and emotion can be explained by taking into account its modulator role on several neurotransmitter systems, acetylcholine in particular, but also catecholamines,serotonin and GABA in rodents, primates and humans. Another reason may lie in the wide spread presence of the two classes (a and~) of estrogen receptors in many brain regions involved in emotion and cognition, including the hippocampal formation, amygdala and cerebral cortex. The present review reports on research conducted in our laboratory and others with the objective of identifying the action of estrogens on cognition and emotion in rodents, monkeys and humans in youth. In particular, the first section,focused on the mechanisms of estrogens action in the brain, illustrates the involvement of estrogen receptors and neurotransmitters in the cognitive and emotional processes; the second section deals with the estrogen effects on cognitive and emotional mechanisms, with particular emphasis on memory and the involvement of estrogen in emotion and cognition across the estrous/menstrual cycle.

Effective connectivity within the corticothalamic circuit in the neuromyelitis optica patients: A comparative study using resting-state fMRI.

Neuromyelitis Optica, which is known as NMO, is a demyelination syndrome and inflammatory condition of the central nervous system that affects the optic nerves. Since structural imaging approaches cannot adequately describe the brain disorders in patients with NMO, functional magnetic resonance imaging (fMRI) can be used. Resting-state fMRI was performed on 25 healthy subjects and 26 NMO patients. After preprocessing the data, the time series belonging to the regions of the middle frontal gyrus (MFG), inferior frontal gyrus (IFG), precuneus (PRE), thalamus (THA), and middle temporal gyrus (MTG) were extracted as components of the corticothalamic circuit. The obtained time series were statistically analyzed as the input of dynamic causal modeling (DCM) in order to evaluate the effective connectivity within the corticothalamic circuit. The statistical analyses showed that the mean of effective connectivity power was significantly higher in the healthy subjects than in the NMO patients. For the healthy subjects, there was no significant difference in effective connectivity power between the two groups of males and females at the significance level of 0.05. In the NMO patients, there was a significant difference between the effective connectivity levels of the male and female groups only for IFG â†’ MFG, in which it was greater in males than in females. The results of our studies showed that resting-state fMRI could exhibit the difference between healthy and NMO subjects.

Study of Geometric Illusory Visual Perception - A New Perspective in the Functional Evaluation of Children With Strabismus.

Despite the various perceptual-motor deficits documented in strabismus, there is a paucity of studies evaluating visual illusions in patients with strabismus. The aim of this study was to examine how the illusionary perception occurs in children/adolescents (10-15 years old) with strabismus with referral for surgery to correct ocular deviations. A controlled cross-sectional study was carried out in which 45 participants with strabismus and 62 healthy volunteers aged 10-15 years were evaluated. The behavioral response to three geometric illusions [Vertical-Horizontal illusion, Müller-Lyer illusion (Bretano version) and Ponzo illusion] and respective neutral stimuli (non-illusory images) regarding the estimation of image size and response time were measured using the Method of Adjustment. To analyze the influence of secondary factors: type of ocular deviation (convergent, divergent or associated with vertical deviation); amount of eye deviation; presence of amblyopia and stereopsis, a one-way ANOVA was performed. Among the tested illusions, children with strabismus showed greater susceptibility (p = 0.006) and response time (p = 0.004) to Ponzo's illusory images. Children with strabismus and preserved stereopsis, on the other hand, showed similar susceptibility and response time to control group patients to the Ponzo illusion (p < 0.005). Patients with amblyopia showed overcorrection in the estimate of non-illusory Ponzo images (p = 0.046). Children with horizontal ocular deviation (esotropia or exotropia) associated with vertical deviation (hypertropia, DVD and/or alphabetical anisotropy) showed higher susceptibility to vertical adjustment images for the Müller-Lyer illusion (Brentano version) (p = 0.017). Individuals with strabismus tended to overcorrect the length of the straight-line segment adjusted for non-illusory images when testing non-illusory images in the Müller-Lyer test (Brentano version) (p = 0.009), as well as for the neutral images in the Vertical-Horizontal test (p = 0.000). The findings indicated impairment in the perception of geometric illusions and neutral figures, especially for the Ponzo illusion test by children with strabismus. As the behavioral response to illusory images may indirectly reflect the visual and morphofunctional alterations present in these individuals, we suggest that the investigation of visual illusory perception can be used as a new research strategy in the field of investigating the visual function in strabismus.

Discovery of two novel Torque Teno viruses in Callithrix penicillata provides insights on Anelloviridae diversification dynamics.

The development of high-throughput sequencing (HTS) technologies and metagenomics protocols deeply impacted the discovery of viral diversity. Moreover, the characterization of novel viruses in the Neotropical primates (NP) is central for the comprehension of viral evolution dynamics in those hosts, due to their evolutionary proximity to Old World primates, including humans. In the present work, novel anelloviruses were detected and characterized through HTS protocols in the NP Callithrix penicillata, the common black-tufted marmoset. De novo assembly of generated sequences was carried out, and a total of 15 contigs were identified with complete Anelloviridae ORF1 gene, two of them including a flanking GC-rich region, confirming the presence of two whole novel genomes of ~3 kb. The identified viruses were monophyletic within the Epsilontorquevirus genus, a lineage harboring previously reported anelloviruses infecting hosts from the Cebidae family. The genetic divergence found in the new viruses characterized two novel species, named Epsilontorquevirus callithrichensis I and II. The phylogenetic pattern inferred for the Epsilontorquevirus genus was consistent with the topology of their host species tree, echoing a virus-host diversification model observed in other viral groups. This study expands the host span of Anelloviridae and provides insights into their diversification dynamics, highlighting the importance of sampling animal viral genomes to obtain a clearer depiction of their long-term evolutionary processes.

Inhibitory control training in healthy and highly educated older adults.

Executive function training is considered a promising tool for delaying the natural effects of aging on cognition. However, there are still few studies that propose a unimodal intervention with a focus on inhibitory control, and none of them has studied the effect of this type of intervention on older adults (OA). OBJECTIVE: The aim of this study is to investigate the benefits of inhibitory control training in healthy OA by comparing the two assessment time points, namely, before and after training. METHODS: Twenty-seven participants were included after interview and checking the inclusion criteria. The training was based on the stop-signal paradigm and carried out in 21 sessions. RESULTS: Participants performed better after training by reducing the false alarm error rate (i.e., for stop-signal trials), reducing omission error rate, showing an increase in hit rate, Go response time (i.e., for go-signal trials), stop-signal response time, and showing a decrease in the level of anxiety. The executive function training had no significant impact on the scores obtained in the complementary neuropsychological tests. CONCLUSIONS: These results are consistent with previous studies that support the viability and effectiveness of cognitive intervention for executive functions in OA and suggest a positive effect of the intervention, which may be related to the learning experience of a new and challenging task.

O treinamento das funções executivas é considerado uma ferramenta promissora para retardar os efeitos naturais do envelhecimento na cognição. No entanto, ainda são poucos os estudos que propõem uma intervenção unimodal com foco no controle inibitório, e nenhum deles estudou o efeito desse tipo de intervenção em idosos. OBJETIVO: Investigar os benefícios do treinamento de controle inibitório em idosos saudáveis, comparando os dois momentos da avaliação: antes e depois do treinamento. Método: Um total de 27 participantes foi incluído após entrevista e verificação dos critérios de inclusão. O treinamento foi baseado no paradigma Stop-Signal e realizado em 21 sessões. RESULTADOS: Os participantes tiveram um melhor desempenho após o treinamento, reduzindo a taxa de erro de alarme falso (nas tentativas stop), reduzindo a taxa de omissões e mostrando aumento na taxa de acerto e GoTR (nas tentativas go), no SSRT e mostrando uma diminuição significativa no nível de ansiedade. O treinamento não teve impacto significativo nas pontuações obtidas nos testes neuropsicológicos complementares. CONCLUSÕES: Esses resultados são consistentes com estudos anteriores que sustentam a viabilidade e eficácia da intervenção cognitiva para funções executivas em idosos, além de sugerirem um efeito positivo da intervenção, que pode estar relacionado à experiência de aprendizagem de uma tarefa nova e desafiadora.

Comparative anatomy of the encephalon of new world primates with emphasis for the Sapajus sp.

Studies about the anatomy of the New World Primates are scarce, mainly comparative neuroanatomy, then a morphological comparative analysis about the tropical Primates were performed and a effort was made for an Old World Primates and modern humans relationship for the obtained data; plus, comments about behavior e and allometry were performed to try link the high cognition and abilities of the Sapajus with the neuroanatomical results, however, despite the deep neuroanatomic data obtained, we do not found an intrinsic relation to explain that.

Cognitive impairment in Parkinson's disease: A clinical and pathophysiological overview.

Cognitive dysfunction in Parkinson's disease (PD) has received increasing attention, and, together with other non-motor symptoms, exert a significant functional impact in the daily lives of patients. This article aims to compile and briefly summarize selected published data about clinical features, cognitive evaluation, biomarkers, and pathophysiology of PD-related dementia (PDD). The literature search included articles indexed in the MEDLINE/PubMed database, published in English, over the last two decades. Despite significant progress on clinical criteria and cohort studies for PD-mild cognitive impairment (PD-MCI) and PDD, there are still knowledge gaps about its exact molecular and pathological basis. Here we overview the scientific literature on the role of functional circuits, neurotransmitter systems (monoaminergic and cholinergic), basal forebrain, and brainstem nuclei dysfunction in PD-MCI. Correlations between neuroimaging and cerebrospinal fluid (CSF) biomarkers, clinical outcomes, and pathological results are described to aid in uncovering the neurodegeneration pattern in PD-MCI and PDD.

Continuous Use of Combined Hormonal Contraceptive and the Effect on Blood Coagulation Factors in Female Capuchin Monkeys (Sapajus libidinosus).

This study aimed at evaluating the availability of the primate Sapajus libidinosus as an animal model for research assessing the physiological effects of the continuous use of combined hormonal contraceptives. In order to do this, six reproductively active female S. libidinosus from the Primate Research Center of the University of Brasília were selected to take part in this experiment. Every 21 days or so, each female received a single dose of combined hormonal contraceptive (algestone acetophenide and 17-enanthate estradiol) in a total of five doses throughout the experiment. The physiological parameters were accessed by means of 13 blood samples from each female, whereas three were gathered during the baseline and 10 samples were collected during the treatment phase. The results showed that the contraceptive use provoked changes in hematological coagulation factors such as an increase in the amount of platelets (p = 0.039) and a reduction in both prothrombin (p < 0.001) and thromboplastin coagulation time (p < 0.001). These results are similar to what has been observed in human patients; thus, it is concluded that S. libidinosus can be successfully used in studies about the physiological impact of hormonal contraceptives.

The Müller-Lyer illusion as a tool for schizophrenia screening.

The perceptual deficit hypothesis for schizophrenia is based on more general models of normal human visual perception, which have traditionally postulated that objects must compete for attention and processing space in the visual system. Recent evidence suggests that susceptibility of schizophrenics to the Müller-Lyer (ML) illusion may be a marker of vulnerability, detectable in prodromic patients, but disappearing with the progression of the illness. This illusion consists of overestimating the length of a straight line with converging arrowheads at the ends, while underestimating those with diverging arrowheads. Although the ML illusion has been shown to occur in touch as well as vision, it is not known whether abnormal contextual suppression extends to other sensory modalities in schizophrenics. Another challenge consists in verifying whether different visual parameters of the illusion which favor the magnocellular and parvocellular systems would have diverse ML illusion effects in schizophrenia. In this review we present data showing the degree of illusion in capuchin monkeys (Cebus spp.), a possible animal model for schizophrenia. To this end, a computer program was developed to conduct experiments in humans and non-human primates, allowing the display of illusory figures, manipulation of the stimuli's exposure time, interval between stimuli and number of trials. In the non-primate experiments, the visual illusion test based on achromatic ML illusion figures indicated the presence of the ML illusory effect in 10 capuchin monkeys. These results suggest that Cebus might be a good model for the experimental study of schizophrenia.

Working memory for emotional facial expressions: role of estrogen in humans and non-human primates.

In recent years, numerous studies focusing on the role of sex steroid hormones on neuropsychological functions have been reported. The influence of estrogens on cognition can be explained by the widespread presence of estrogen receptors (ERs) in limbic and cortical areas, and the modulator role of estrogens on numerous neurotransmitter systems. There is a great deal of evidence suggesting that estrogen can enhance memory processes and improve performance in working memory (WM) tasks, including face-tasks, delayed matching-to-sample (DMTS) and delayed non-matching-to-sample (DNMTS). The modulator effects exerted by estrogens are complex and may vary according to task, gender, and phase of the menstrual cycle. For many years, physiological hormonal fluctuations during the menstrual cycle, postpartum, and menopause have been said to influence mood, cognition, and affective disorders. In addition, it has been hypothesised that estrogens have a protective role in schizophrenia and Alzheimer's disease (AD). Taking into account that women's performance in memory tasks can also fluctuate with circulating hormone levels across the menstrual cycle, data related to the cognitive performance in a WM task for emotional facial expressions were reported. The findings described in this review can contribute to clarifying the role of the steroid hormone estrogen in the modulation of cognitive functions, particularly memory, and indicate the possible usefulness of applying a new paradigm, employing a DNMTS task with emotional facial expressions, in studies focused on emotional WM in relevant models of nonhuman primates. Such data could also represent a useful tool in individualizing effective therapy for the treatment of disturbances linked to menstrual cycle phases and menopause in women.

Working memory for emotional facial expressions: role of the estrogen in young women.

Physiological hormonal fluctuations during the menstrual cycle, postpartum, and menopause have been implicated in the modulation of mood, cognition, and affective disorders. Taking into account that women's performance in memory tasks can also fluctuate with circulating hormones levels across the menstrual cycle, the cognitive performance in a working memory task for emotional facial expressions, using the six basic emotions as stimuli in the delayed matching-to-sample, was evaluated in young women in different phases of the menstrual cycle. Our findings suggest that high levels of estradiol in the follicular phase could have a negative effect on delayed matching-to-sample working memory task, using stimuli with emotional valence. Moreover, in the follicular phase, compared to the menstrual phase, the percent of errors was significantly higher for the emotional facial expressions of sadness and disgust. The evaluation of the response times (time employed to answer) for each facial expression with emotional valence showed a significant difference between follicular and luteal in reference to the emotional facial expression of sadness. Our results show that high levels of estradiol in the follicular phase could impair the performance of working memory. However, this effect is specific to selective facial expressions suggesting that, across the phases of the menstrual cycle, in which conception risk is high, women could give less importance to the recognition of the emotional facial expressions of sadness and disgust. This study is in agreement with research conducted on non-human primates, showing that fluctuations of ovarian hormones across the menstrual cycle influence a variety of social and cognitive behaviors. Moreover, our data could also represent a useful tool for investigating emotional disturbances linked to menstrual cycle phases and menopause in women.

Prolonged effects of intra-nasally administered testosterone on proceptive behavior in female capuchin monkeys (Cebus apella).

Sexual dysfunction in the female has been associated with a decrease in androgen levels, which can be reversed by testosterone treatment, however, bearing the risk of adverse side effects. Previously we found that intranasal application of testosterone led to an increase in proceptive behavior in female capuchin monkeys, which was still enhanced beyond treatment pointing to prolonged effects. Here, we sought to replicate our previous findings and to further examine possible prolonged effects of such treatment. During 5 days of baseline females were observed for their sexual and non-sexual behavior without drug. They then received daily intranasal testosterone (0.24 mg per nostril) for 7 days, followed by 15 days of intranasal testosterone application every third day or were left undisturbed (n=5 per group). Diverse sexual and non-sexual behaviors were scored. Blood samples were collected and analyzed for testosterone, estradiol, and progesterone using immunoenzymatic chemiluminescent immunoassay. In accord with our previous results an increase in sexual proceptive behavior was revealed during testosterone treatment, which persisted about 2 weeks beyond treatment in the group receiving testosterone every third day as well as in the group that no longer received any treatment. These behavioral results were accompanied by an increase in plasma testosterone levels. This study demonstrates the efficacy of testosterone in enhancing sexual behavior in female capuchin monkeys by means of intranasal application, and provided evidence that daily substance application is not necessary to maintain beneficial effects on sexual behavior. These findings render the intranasal application procedure to be a useful alternative compared to other forms of administration.