A trapaça é rara, mas é bem lembrada: o efeito da cor da pele e do gênero na memória de faces

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

A relação de amizade nas redes sociais de estudantes universitários de Natal/RN

The basis of sociability in humans is based on cooperation. The relationship of friendship is vital to the social, emotional and cognitive development of an individual and can be understood as a consequence of selection for reciprocal altruism in humans. The period of adulthood is considered very suitable and appropriate for the investigation of the relations of friendship, but the Brazilian literature on friendship in adults is still nascent. Therefore, the objective was to characterize the relationship of friendship among college students. The study gathered 500 students from higher education institutions in the city of Natal-RN, Brazil, and 250 women (average age 24.1 ± 7.66 years) and 250 men (mean age 26.77 ± 9.64 years). Two questionnaires anonymously and individual were applied: a sociodemographic questionnaire and the other with the desired characteristics in idealized friends. Study 1 assessed the degree of importance of characteristics in the process of choosing a friend of the same sex and opposite sex of the participant. Study 2 investigated the relationship between patterns of idealization of friends and self-assessment of participants. Overall, were the preferred characteristics "Companionship" and "Sincerity" to idealized friends. We also found the influence of sex on the characteristics attributed to an female ideal friend, with emphasis on men for "Beauty/Good looks" and "Intelligence" and women to "Companionship" and "Sincerity". Finally, we observed a positive correlation between participants' self-assessment and preferences for the characteristics of the friends devised. This study revealed important elements for understanding the relationship of friendship, specifically the process of choosing friends. The results reinforce the importance of studying the relationship of friendship to a better understanding of human social behavior.

Caracterização da frequência de atividades aéreas do golfinho-rotador, Stenella longirostris (Gray, 1828), na Baía dos Golfinhos do Parque Nacional Marinho de Fernando de Noronha

The aerial activities, leaps and slaps with parts of the body in the surface of water, are part of the behavioral repertoire of several species of cetaceans. Among them, the spinner dolphin, Stenella longirostris, shows greater diversity in such behavior. For the spinner dolphins of Fernando de Noronha, the aerial activities are classified as vertical and horizontal, with eight patterns to be noted (tail slap, head slap, motor boating, partial leap, leap, spin, tail over head and tail over head with spin) discriminated between these categories. Such behaviors can be used as a parameter to identify behavioral changes, as well as patterns of daily and seasonal activity. In this manner, this study aimed to characterize the frequency in performance of such activity while the dolphins were within the Dolphin Bay of Fernando de Noronha, and verify possible daily and seasonal hourly fluctuations on such behaviors. The data analyzed in this study was acquired during the period of January 2006 through December 2010, totaling 1431 days of observation from land set point, with 113027 aerial activities registered, daily average of 72,27 (SD=96,10). During 5478h and 54 min of observation the horizontal aerial activity was the most observed and rotation was the most executed pattern. Greater frequency of execution of aerial activity was observed in adults, but for both adults and calves, was observed a predominance of horizontal activities, with spin being the pattern most executed. Positive correlation was observed between the amount of aerial activity performed and the number of animals inside the Bay. Hourly daily fluctuation was observed in the expression of aerial activities by spinner dolphins, and was observed a peak of activity between 8h and 8h59min for the overall frequency relative of aerial activities, as well as for the categories and patterns. Seasonal differences were observed between the rainy and dry season with the greater amount of activity being observed during the rainy season. Nevertheless, the same profile of frequency relative of aerial activity was observed in both seasons with the peak amount being during the same period. When discriminated the aerial activities in categories and patterns, for both seasons, there was a similar pattern of hourly fluctuation; for most of parameters, higher frequency relative of execution of aerial activity remain between 8h and 8h59min

Proposta de Intervenção para Auxiliar a Reabilitação Motora e Cognitiva de Pacientes com Acidente Vascular Cerebral

Stroke is the leading cause of combined motor and cognitive disability worldwide. The rehabilitation of stroke patients is mostly directed towards motor recovery through the training of the affected member under supervision of a Physical Therapist. In the present study we introduce a new approach for both cognitive and motor therapy, which relies on motor imagery of the upper limbs and working memory training. This therapy should be utilized as an adjuvant to physical therapy. Ten individuals (5 men and 5 women) were selected for the pilot study, all of them in the acute phase of the first ischemic stroke episode. The control group had 5 individuals who were submitted to physical therapy only, whilst the other 5 patients in the experimental group also performed the cognitive and motor training with a video game specially built for this study. Two patients left the experimental group before the end. Total training lasted for 9 weeks, 2 times a week, for half an hour. Patients reported they enjoyed playing the game, even though it required a lot of mental effort, according to them. Plus, they considered it had a beneficial influence in their activities of daily living. No side effects were reported. Preliminary results suggest there is a difference between groups in cognitive and upper limb motor evaluation following the intervention. It is important to notice that our conclusions are limited due the small sample number. Overall, this work is supported by other studies in literature focused in rehabilitation with motor imagery and working memory and indicate a continuity of the research, increasing total training hours

Avaliação dos efeitos do biperideno, diazepam e neuropeptídeos S sobre a memória e a ansiedade na tarefa do labirinto em T elevado em camundongos

Anxiety is an emotional phenomenon, and normally it is interpreted as an adaptative behavior front to adversities. In its pathological form, anxiety can severely affect aspects related to the personal and professional life. Studies have shown a close relationship between anxiety disorders and aversive memory processing. Considering that the pharmacotherapy of anxiety disorders is still limited, innovative anxiolytic agents are needed. In this regard, neuropeptides systems are interesting therapeutic targets to the treatment of psychopathologies. Neuropeptide S (NPS), a 20-aminoacid peptide, is the endogenous ligand of a G-protein coupled receptor (NPSR), which has been reported to evoke hyperlocomotion, awakefull states, besides anxiolysis and memory improvements in rodents. This study aimed to investigate the effects of biperiden (BPR; an amnesic drug), diazepam (DZP; an anxiolytic drug) and NPS at three distinct times: pre-training, post-training, and pre-test, in order to assess anxiety and memory process in the same animal model. The elevated Tmaze (ETM) is an apparatus derived from the elevated plus-maze test, which consists of one enclosed and two open arms. The procedure is based on the avoidance of open spaces learned during training session, in which mice were exposed to the enclosed arm as many times as needed to stay 300 s. In the test session, memory is assessed by re-exposing the mouse to the enclosed arm and the latency to enter an open arm was recorded. When injected pre-training, BPR (1 mg/kg) impaired learning and memory processing; DZP (1 and 2 mg/kg) evoked anxiolysis, but only at the dose of 2 mg/kg impaired memory; and NPS 0.1 nmol induced anxiolysis without affecting memory. Post-training injection of DZP (2 mg/kg) or BPR (1 and 3 mg/kg) did not affect memory consolidation, while the post-trainning administration of NPS 1 nmol, but not 0.1 nmol, improved memory in mice. Indeed, pre-trainning administration of NPS 1 nmol did not prevent memory impairment elicited by BPR (2 mg/kg, injected before training). In the open field test, BPR 1 mg/kg and NPS 1 nmol induced hyperlocomotion in mice. In conclusion, the proposed ETM task is practical for the detection of the anxiolytic and amnesic effects of drugs. The anxiolytic and memory enhancement effects of NPS were detected in the ETM task, and reinforce the role of NPS system as an interesting therapeutic target to the treatment of anxiety disorders

Alterações do ciclo sono-vigília moduladas por Dopamina e suas consequências Mnemônicas

Neuroscience is on a rise of discoveries. Its wide interdisciplinary approach facilitates a more complex understanding of the brain, covering various areas in depth. However, many phenomena that fascinate human kind are far from being fully elucidated, such as the formation of memories and sleep. In this study we investigated the role of the dopaminergic system in the process of memory consolidation and modulation of the phases of sleep-wake cycle. We used two groups of animals: wildtype mice and hiperdopaminergic mice, heterozygous for the gene encoding the dopamine transporter protein. We observed in wild-type mice that the partial blockade of the D2 dopamine receptor by the drug haloperidol caused deficits in memory consolidation for object recognition, as well as a significant reduction in the duration of rapid eye movement sleep (REM). We also found a mnemonic deficit without pharmacological intervention in hiperdopaminergic animals; this deficit was reversed with haloperidol. The results suggest that dopamine plays a key role in memory consolidation for object recognition. The data also support a functional relationship between the dopaminergic system and the modulation of REM sleep

A influência do feedback verbal na cooperação em crianças

Human cooperation is a hallmark of this species due to its wide extension to genetically unrelated individuals and complex division of labor. It is considered an evolutionary puzzle, because the theory of evolution by natural selection predicts that self-interested individuals tend to be selected. Different theories have been proposed to explain the evolution of cooperation, which the most important are kin selection and reciprocal altruism. Considering the evolutionary continuity between species, humans and other primates have several common traits that help to promote cooperation between individuals of these species. Two features, however, seem to be particularly humans: inequality aversion and preferences in relation to others. Although human cooperation is not necessarily related to morality, cooperative traits are the basis for moral tendencies. The development of human morality is a combination of early prosocial tendencies, cooperative skills displayed at different ages, social learning and cultural transmission of norms. The social stimulus seems to be particularly important in promoting cooperative behavior in children and adults. In order to study the influence of social stimuli, as verbal feedback, on children cooperation, a study was conducted with children in a public goods game. 407 children from public schools in Natal / RN, divided into 21 groups, between six and nine years, participated in eight rounds of this game. After each round, seven groups received praise for larger donations, seven groups have been criticized by smaller donations, and the other seven received no comment. Children cooperated more when criticized, without significant differences between sexes, although young children have cooperated more negative than older children. The results are likely related to the anticipation and avoidance of punishment associated with the feedback (although this did not occur), and greater sensitivity to the authority in younger children. Nevertheless, the cooperation decreased in all groups until the last day of play. The results suggest an early sensitivity to moral punishment, whose role in the maintenance of social relations must have been important in the evolution of cooperation in humans

Participação do circuito dopaminérgico nas alterações do comportamento de medo inato de camundongos infectados pelo Toxoplasma gondii

The protozoan parasite Toxoplasma gondii transforms the innate aversion of rats for cat urine into a fatal attraction, that increases the likelihood of the parasite completing its life cycle in the cat s intestine. The neural circuits implicated in innate fear, anxiety, and learned fear all overlap considerably, raising the possibility, that T. gondii may disrupt all of these nonspecifically. In this study, we evaluated immunoreactivity for tyrosine hydroxylase (TH) in areas associated with innate fear of infected male swiss mice. The latent Toxoplasma infection converted the aversion of mice to feline odors into attraction. This loss of fear is remarkably specific, as demonstrated by Vyas et al (2007), because infection did not diminish learned fear, anxiety-like behavior, olfaction, or nonaversive learning. However, the neurochemical mechanism related to alterations in innate fear due to T. gondii infection remains poorly studied. 20 mice were inoculated with bradyzoites (25 cysts) from a Toxoplasma gondii (Me-49 strain). The brains were removed after 60 days, sectioned and processed for TH immunohistochemistry. The correlation between the amount of cysts per area and the densitometric analysis of neurotransmitter reactivity was low in the areas implicated in innate fear of infected animals, when comparated with noninfected controls

Padrão de atividades do sagüi callithrix jacchus numa área de caatinga

Callithrix jacchus, as the other species in the family Callitrichidae, lives in social groups. The groups cam be found in different habitats, whose distinct floristic physiognomies and communities are intrinsically related to their behavioral ecology and social relations. Our objective was to describe the social relations and feeding behavior of Callithrix jacchus in the Bioma Caatinga. We observed a group at the FLONA (National Forest IBAMA), in Açu-RN, in northeastern Brazil, compose of five adults (2 females and 3 males) at the beginning of the study. The birth of five animals was registered along the study. The following behavioral categories were registered along eleven months, once a week, through instantaneous focal animal sampling: social grooming, contact, proximity, foraging, feeding, locomotion and rest. Foraging presented the highest levels comparing to other activities, and was more frequent in the dry season. Social grooming was the second more frequent activity, with higher levels in the rainy season, and between the reproductive couple. We found similar results for proximity. The most explored feeding item was the gum, specially in the rainy season. The most explored species for exudates feeding were Cirus limon (limão) and Pitecolobiun foliolosum (jurema branca). The comparision of fruit and insect ingestion between the seasons showed higher percentage for both in the dry season. The general activity pattern was similar to what is registeded in groups the inhabit the Atlantic Forest. These results indicate the flexibility of the species which survives and reproduces in such physically and biologically different environments

Influência da idade, do sexo e da hora do dia no desempenho em teste de labirinto

The increase of elderly population in the world and in Brazil has indicated the necessity of health systems capable to evaluate, to diagnose and to intervene in the conditions of health and disease of that segment. During that stage of human development, physical and cognitive changes happen and they are capable to influence the functional acting. It s important to distinguish the limit between the normal and the pathological. Besides the common changes during the aging, biological rhithmicity changes happen, as alterations in the cycle vigil-sleep that can influence in certain tasks performance. This study aimed to verify the influence of the age, of the sex and of the hour in a maze test performance. Eighty individuals were evaluated, 40 youths (20 men and 20 women) and 40 senior (20 men and 20 women). They were separated in 2 different groups that were tested at 9:00 o clock and at 15:00 o clock. Initially they were submitted to health evaluation, cognitive evaluation and of sleep quality and chronotype. They were instructed to accomplish the maze test whose time of execution was timed and registered. Significant differences were observed according to age for the masculine group between elderly in the morning and in the afternoon and in the feminine group between youth and elderly in the test accomplished in the morning and in the afternoon. Significant differences were not observed according to sex and hour of the day and also between attempts. In compare between the 30th and the31st, accomplished in a 15minutes of interval, significant difference was observed just for the elderly group in the morning and in the afternoon. We observed significant correlations in the maze test performance with the cronotype, with the age, with the education and with the cognitive acting. The maze test was capable to detect differences between age in the acting profile and in the evaluation of the information maintenance after 15 minutes, however it was not possible to verify difference between sex and hour of the day. Finally the correlations of the maze test with another varied may indicate your importance as coadjutant instrument in those functions evaluation

Desenvolvimento dos filhotes de atobas-de-pés-vermelhos (Sula sula) no aquipélego de Fernando de Noronha/PE

Parental care s costs increase with the time spent due to incapacity of parents give assistance to increasing offspring food s requirement. This parental care deficits is crucial to offspring s emancipation that involve abilities development to they survive independently. In this work we observe 16 Red-footed boobies chick (Sula sula) on different stages of development, at area of Parque Nacional Marinho of Fernando de Noronha s archipelago, from August to October of 2005. Our data show the parents presence decrease during chick development and an activity frequency modification, in move and fly, which suggest the emancipation s chick development. We observe also the action of Kleptoparasits and the influence with offspring parental care. Our data show consistency with the literature. However, we consider that studies carried through during the peak of the reproductive station can support the hypothesis of that the conflicts, together with the initial period of development of the flight, can be representative in terms of mortality of chicks for the studied species

Memória de reconhecimento em indivíduos adultos com mais de 45 anos

As we grow old, there are many cognitive processes which decline in the human brain. One of them is the memory, a function that allows retention and posterior use of knowledge learned during the life, understood as a result of multiple systems highly organized and spread in several neural regions. This work aimed to evaluate the recognition memory in adults over 45 years old through words and pictures recognition tasks and the use of two codification or learning conditions (same distracters and different distracters). Twelve individuals were studied (6 men and 6 women) aged between 45 and 88 years old and with similar demographic characteristics. They presented better performance on picture tasks rather than word tasks. Better results were also verified when the codification context had different distracters, which significantly reflected in a long term principally in elderly individuals. The results reached suggest that the codification context influenced the lists of pictures and words learning, mainly for the elderly ones, when compared to adults, and that these results can be related to the phenomena involved with the recognition memory, the recollection and familiarity

Efeitos do substrato e da densidade populacional sobre as atividades comportamentais e níveis de homócitos em relação à densidade em Litopenaeus vannamei (BOONE, 1931)

Carciniculture in Brazil occupies world-wide prominence due to shrimp culture, and the state of Rio Grande do Norte has presented the best results in the culture of the Litopenaeus vannamei in the last decade. This species has been shown to adapt easily to different environments and is between the five most cultivated penaeids of the world. The ponds are usually constructed in areas close to water courses and estuaries. Stock density and substrate ponds can pollute environment, causing losses in the growth and survival of the shrimps, being considered stress factors. Shrimps in inadequate densities and substrates can result reduced productivity of the farm; and favor diseases. So, it is important to verify how these variables influence the development of the animals in the culture farms. Our objective was to study the influence of the type of substrate and the stock density on the behavior and haemocyte count of the L. vannamei. Individually marked juvenile shrimps were kept in aquaria with 30 L of seawater and continuous aeration, in 12L-12D photoperiod. They were observed through Ad libitum and focal sampling instantaneous methods during thirty days, five times per week, six times per day (8:00 to 18:00) in windows of 15 minutes every two hours. The marking of carapace permitted quantifying molting and the feeding was supplied three times a day. Two experiments were carried out: the first one tested animals in the three different substrates (fine sand, smaller rocks-SPP and biggest rocks-SGR) with 33 shrimp/m2. In the second one, the animals were tested in three stock densities (26, 52 and 66 shrimp/m2) in fine sand substrate. At the end of experiment, biometry (first and second ones) and haemocyte count (second one) were made. The behavior of the L. vannamei seems to have been influenced by substrate and stocking density. In low granulometry of the substrate; the exploratory behavior became more frequent and inactivity of the shrimps was reduced. Burrowing was registered in sand substrate, specially in the initial period of the day. Cleaning was gradually higher along the day, presenting the biggest levels as the dark phase approached. The ingestion of feeding was more frequent in low density, and the animals were bigger and heavier at the end of the experiment. In the fine sand condition, the animals presented better growth, probably associated with the burrowing. The molting was equivalent in all types of substrate, but it was more frequent in high densities. Mortality of the shrimps was more frequent in high densities, and cannibalism and diseases were also registered in that condition. The clinical signals were similar to the ones of infectious mionecrosis (IMNV), generally associated with environment and physical stress. The haemocyte count was low for the hematologic standards of the penaeid, which we attributed for greater dilution of haemolymph in the postmolting phase. Smaller shrimps presented lower levels of haemocytes in relation to the bigger animals, count was also low in 26 shrimp/m2 density. The study demonstrates that stocking density and the granulometry of the substrate can affect the welfare, the health and the behavior of the L. vannamei. The sand substrate and low stocking density can be important tools in the management systems of shrimp production

Participação da neurotransmissão dopaminergica no efeito hiperlocomotor do neuropeptideo S

Neuropeptide S (NPS) is an endogenous 20-aminoacid peptide which binds a G protein-coupled receptor named NPSR. This peptidergic system is involved in the modulation of several biological functions, such as locomotion, anxiety, nociception, food intake and motivational behaviors. Studies have shown the participation of NPSR receptors in mediating the hyperlocomotor effects of NPS. A growing body of evidence suggests the participation of adenosinergic, dopaminergic and CRF systems on the hyperlocomotor effects of NPS. Considering that little is known about the role of dopaminergic system in mediating NPS-induced hyperlocomotion, the present study aims to investigate the locomotor actions of intracerebroventricular (icv) NPS in mice pretreated with α-metil-p-tirosine (AMPT, inhibitor of dopamine synthesis), reserpine (inhibitor of dopamine vesicle storage) or sulpiride (D2 receptor antagonist) in the open field test. A distinct group of animals received the same pretreatments described above (AMPT, reserpine or sulpiride) and the hyperlocomotor effects of methylphenidate (dopamine reuptake inhibitor) were investigated in the open field. NPS and methylphenidate increased the mouse locomotor activity. AMPT per se did not change the locomotion of the animals, but it partially reduced the hyperlocomotion of methylphenidate. The pretreatment with AMPT did not affect the psychostimulant effects of NPS. Both reserpine and sulpiride inhibited the stimulatory actions of NPS and methylphenidate. These findings show that the hyperlocomotor effects of methylphenidate, but not NPS, were affected by the pretreatment with AMPT. Furthermore, methylphenidate- and NPS-induced hyperlocomotion was impaired by reserpine and sulpiride pretreatments. Together, data suggests that NPS can increase locomotion even when the synthesis of catecholamines was impaired. Additionally, the hyperlocomotor effects of NPS and methylphenidate depend on monoamines vesicular storaged, mainly dopamine, and on the activation of D2 receptors. The psychostimulant effects of NPS via activation of dopaminergic system display clinical significance on the treatment of diseases which involves dopaminergic pathways, such as Parkinson s disease and drug addiction

O Tratamento com a fluoxetina (mas não com outros farmacos antidepressivo e ansioíiticos) reverte o déficit de memória aversiva causado por estresse agudo de contenção em camundongos

The physiologist H. Selye defined stress as the nonspecific response of the body to any factors that endanger homeostasis (balance of internal environment) of the individual. These factors, agents stressors, are able to activate the Hypothalamic-Pituitary-Adrenal (HPA) axis, thus resulting in the physiological responses to stress by the release of glucocorticoids that leads to psychophysiological changes, including effects on cognitive functions such as learning and memory. When this axis is acutely stimulated occurs a repertoire of behavioral and physiological changes can be adaptive to the individual. Notwithstanding, when the HPA axis is chronically stimulated, changes may favor the development of, such as anxiety disorders. Some drugs used in the clinic for the treatment of anxiety disorders these can exert effects on cognitive function, on the HPA axis and on the anxiety. In this context, the aim of our study was to investigate the effects of administration i.p. acute of diazepam (DZP, 2 mg/kg), buspirone (BUS, 3 mg/kg), mirtazapine (MIR, 10 mg/kg) and fluoxetine (FLU, 10 mg/kg) in male mice submitted to acute restraint stress, and evaluated using plus-maze discriminative avoidance task (PMDAT), which simultaneously evaluates parameters such as learning, memory and anxiety. Our results demonstrated that (1) the administration of DZP and BUS, but not FLU, promoted anxiolytic effects in animals; (2) administration mirtazapine caused sedative effect to animals; (3) in the training session, the animals treated with BUS, MIR and FLU learned the task, on the other hand DZP group showed impairment in learning; (4) in the test session, animals treated with DZP, BUS, and MIR showed deficits in relation to discrimination between the enclosed arms, aversive versus non-aversive arm, demonstrating an impairment in memory, however, animals treated with FLU showed no interference in the retrieval of this memory; (5) acute stress did not interfere in locomotor activity, anxiety, or learning on the learning task, but induced impairment in retrieval memory, and the group treated with FLU did not demonstrated this deficit of memory . These results suggest that acute administration of drugs with anxiolytic and antidepressant activity does not interfere with the learning process this aversive task, but impair its retrieval, as well as the acute restraint stress. However, the antidepressant fluoxetine was able to reverse memory deficits promoted by acute stress, which may suggest that modulation, even acutely serotonergic neurotransmission, by selectively inhibiting the reuptake of this neurotransmitter, interferes on the process of retrieval of an aversive memory