Aspectos epidemiológicos, cognitivo-comportamentais e neurofisiológicos do sonho lúcido

Lucid dreaming (LD) is a mental state in which the subject is aware of being dreaming while dreaming. The prevalence of LD among Europeans, North Americans and Asians is quite variable (between 26 and 92%) (Stepansky et al., 1998; Schredl & Erlacher, 2011; Yu, 2008); in Latin Americans it is yet to be investigated. Furthermore, the neural bases of LD remain controversial. Different studies have observed that LD presents power increases in the alpha frequency band (Tyson et al., 1984), in beta oscillations recorded from the parietal cortex (Holzinger et al., 2006) and in gamma rhythm recorded from the frontal cortex (Voss et al., 2009), in comparison with non-lucid dreaming. In this thesis we report epidemiological and neurophysiological investigations of LD. To investigate the epidemiology of LD (Study 1), we developed an online questionnaire about dreams that was answered by 3,427 volunteers. In this sample, 56% were women, 24% were men and 20% did not inform their gender (the median age was 25 years). A total of 76.5% of the subjects reported recalling dreams at least once a week, and about two-thirds of them reported dreaming always in the first person, i.e. when the dreamer observes the dream from within itself, not as another dream character. Dream reports typically depicted actions (93.3%), known people (92.9%), sounds/voices (78.5%), and colored images (76.3%). The oneiric content was related to plans for upcoming days (37.8%), and memories of the previous day (13.8%). Nightmares were characterized by general anxiety/fear (65.5%), feeling of being chased (48.5%), and non-painful unpleasant sensations (47.6%). With regard to LD, 77.2% of the subjects reported having experienced LD at least once in their lifetime (44.9% reported up to 10 episodes ever). LD frequency was weakly correlated with dream recall frequency (r = 0.20, p <0.001) and was higher in men (χ2=10.2, p=0.001). The control of LD was rare (29.7%) and inversely correlated with LD duration (r=-0.38, p <0.001), which is usually short: to 48.5% of the subjects, LD takes less than 1 minute. LD occurrence is mainly associated with having sleep without a fixed time to wake up (38.3%), which increases the chance of having REM sleep (REMS). LD is also associated with stress (30.1%), which increases REMS transitions into wakefulness. Overall, the data suggest that dreams and nightmares can be evolutionarily understood as a simulation of the common situations that happen in life, and that are related to our social, psychological and biological integrity. The results also indicate that LD is a relatively common experience (but not recurrent), often elusive and difficult to control, suggesting that LD is an incomplete stationary stage (or phase transition) between REMS and wake state. Moreover, despite the variability of LD prevalence among North Americans, Europeans and Asians, our data from Latin Americans strengthens the notion that LD is a general phenomenon of the human species. To further investigate the neural bases of LD (Study 2), we performed sleep recordings of 32 non-frequent lucid dreamers (sample 1) and 6 frequent lucid dreamers (sample 2). In sample 1, we applied two cognitive-behavioral techniques to induce LD: presleep LD suggestion (n=8) and light pulses applied during REMS (n=8); in a control group we made no attempt to influence dreaming (n=16). The results indicate that it is quite difficult but still possible to induce LD, since we could induce LD in a single subject, using the suggestion technique. EEG signals from this one subject exhibited alpha (7-14 Hz) bursts prior to LD. These bursts were brief (about 3s), without significant change in muscle tone, and independent of the presence of rapid eye movements. No such bursts were observed in the remaining 31 subjects. In addition, LD exhibited significantly higher occipital alpha and right temporo-parietal gamma (30-50 Hz) power, in comparison with non-lucid REMS. In sample 2, LD presented increased frontal high-gamma (50-100 Hz) power on average, in comparison with non-lucid REMS; however, this was not consistent across all subjects, being a clear phenomenon in just one subject. We also observed that four of these volunteers showed an increase in alpha rhythm power over the occipital region, immediately before or during LD. Altogether, our preliminary results suggest that LD presents neurophysiological characteristics that make it different from both waking and the typical REMS. To the extent that the right temporo-parietal and frontal regions are related to the formation of selfconsciousness and body internal image, we suggest that an increased activity in these regions during sleep may be the neurobiological mechanism underlying LD. The alpha rhythm bursts, as well as the alpha power increase over the occipital region, may represent micro-arousals, which facilitate the contact of the brain during sleep with the external environment, favoring the occurrence of LD. This also strengthens the notion that LD is an intermediary state between sleep and wakefulness

Ritmo circadiano de atividade motora e distribuição diária dos comportamentos afiliativos ao longo da fase juvenil em saguis (callithrix jacchus)

The temporal allocation of the active phase in relation to light and dark cycle (LD) changes during puberty in humans, degus, rats and rhesus. In marmosets, the animal model used in several biomedical researches, there is evidence of a delay at the beginning of the active phase and an increase in total daily activity after onset of puberty. However, as this aspect was evaluated in animals maintained in natural environmental conditions, it was not possible to distinguish between the effects of puberty and of seasonality. Furthermore, as motor activity is the result of different behaviors in this species, it is also important to characterize the diurnal distribution of other behaviors in juvenile stage. With the aim of characterizing the circadian rhythm of motor activity and the diurnal profile of affiliative behavior in marmosets, the motor activity of 5 dyads juveniles between 4 and 12 months of age and their parents was recorded continuously for actímetro. The families were maintained under artificial LD 12:12 h, constant temperature and humidity. The duration of grooming behavior, proximity and social play among juveniles was recorded 2 times a week in sessions of 15 minutes each hour of the active phase. Afetr onset of puberty in juvenile, it was observed that there was no change in the parameters of circadian motor activity rhythm which were common to most animals. Despite the absence of pubertal modulation, it was observed that the circadian activity profiles have stronger synchrony between individuals of the same family than that of different families, which may indicate that the circadian activity rhythm was modulated by the dynamics of social interactions. In relation to age, the total daily activity and the ratio between evening and morning activity (EA/MA) were higher in juveniles than in adults, which may be associated with differences in the circadian timing system between age groups. Furthermore, the onset of the 10 consecutive hours of higher activity (M10) occurred earlier in adult males than in other members of the group, probably as a way to avoid competition for resources in one of the first activities of the day that is foraging. During the juvenile stage, there was an increase in total daily activity that may be associated with increased motor ability of juveniles. In addition to the circadian activity rhythm, the daytime profile of proximity and social play behaviors was similar between the 5th and 12th month of life of juveniles, in which the interval between 7- 10 h in the morning showed the highest values of proximity and lower values of play social. Moreover, the duration of the grooming showed a similar distribution to adults from the 8th month, wherein the higher values occurring at the interval between 11 14 h of day. Considering the results, the parameters of the circadian activity rhythm had a greater influence of social factors than puberty. In relation to age, there were no changes related to the allocation of the active phase in relation to the LD cycle, but total daily activity, the ratio AV/AM and the start of the M10 is possible to observe differences between juveniles and adults

Caracterização do ritmo de atividade/repouso do Mocó (Kerodon Rupestris) em fotoperíodo artificial

Kerodon rupestris (rock cavy, mocó) is an endemic caviidae of Brazilian northeast that inhabits rocky places in the semi arid region. The aim of this study was to characterize the activity/rest rhythm of the rock cavy under 12:12 h LD cycle and continuous light. In the first stage, seven animals were submitted to two light intensities (LD; 250:0 lux and 400:0 lux; 40 days each intensity). In the second stage four males were kept for 40 days in LD (470:<1 lux), for 18 days in LL 470 lux (LL470) and for 23 days in red dim light below 1 lux (LL<1). In the third stage three males were initially kept in LD 12:12 h (450:<1 lux) and after that in LL with gradual increase in light intensity each 21 days (<1 lux LL<1; 10 lux-LL10; 160 lux LL160; 450 lux LL450). In the fourth stage it was analyzed the motor activity of 16 animals in the first 10 days in LD. Motor activity was continuously recorded by passive infrared movement sensors connected to a computer and totaled in 5 min bins. The activity showed circadian and ultradian rhythms and activity peaks at phase transitions. The activity and the rest occurred in the light as well as in the dark phase, with activity mean greater in the light phase for most of the animals. The light intensity influenced the activity/rest rhythm in the first three stages and in the first stage the activity in 400 lux increased in four animals and decreases in two. In the second stage, the tau for 3 animals in LL470 was greater than 24 h; in LL<1 it was greater than 24 h for one and lower for two. In the third stage the tau decreased with the light intensity increase for animal 8. During the first days in the experimental room, the animals did not synchronize to the LD cycle with activity and rest occurring in both phases. The results indicate that the activity/rest rhythm of Kerodon rupestris can be affected by light intensity and that the synchronization to the LD cycle results from entrainment as well as masking probably as a consequence of the action of two or more oscillators with low coupling strength

Boto cinza (Sotalia guianensis, Van Benédén, 1864) (Cetacea, Delphinidae): Atividade aérea, forrageio e interações inter-específicas, na Praia de Pipa (Tibau do Sul RN) e estudo comparativo entre duas populações do Nordeste do Brasil

Sotalia guianensis is a small cetacean of the Delphinidae family, with coastal habits and whose area of distribution ranges from Florianópolis (27º35'S, 48º34'W), in Brazil, to Honduras (15º58'N, 85º42'W). At Pipa beach, on the south coast of RN state, in Brazil, the species occur throughout the year. The present study was carried out in two bays, which are bordered by cliffs. The animals were monitored from vantage points, using the "Ad libitum" and "all the occurrences" methods; during the years of 1999 and 2004. The study was divided in 4 chapters: Behavioral standards of two populations of gray dolphin, (Sotalia guianensis, Van Benédén, 1864) in the northeast of Brazil; Aerial activity of the gray dolphin: its possible function and the influence of environmental and behavioral factors; The influence of daily and monthly variation of the tides, of the period of the day and group size on the gray dolphin forage activity; kleptoparasitism interactions of frigatebird (Fregata magnificens, Mattheus, 1914) during the gray dolphin forage activity. The results have shown that the gray dolphin has a varied and complex behavioral repertoire. The leap is the most frequent behavior; the aerial activity is diffuse during daylight and is influenced by some factors, such as the level of the tide and social factors. The gray dolphin, when in the bay, most frequently feeds isolate or in small groups. The forage is diffuse during daylight; however, being more frequent in the morning and is influenced by the daily and monthly variation of the tide. At Pipa beach, kleptoparasitarian interactions were registered between the gray dolphin and the frigatebird (Fregata magnificens). The frigatebird forage strategy consists basically of two ways: to fly over great extensions searching for dead fish and to steal food (kleptoparasitism). These interactions were predominantly carried out between immature and female adult birds and adult and immature dolphins, and occurred during daylight. The present study can be considered an initial landmark to a better knowledge on the gray dolphin surface behavior, especially regarding the aerial behavioral repertoire and forage strategy of this species. However, it is necessary to continue these studies, so that we can understand better the complex social life of these animals and thus create effective measures for its conservation

Avaliação da estimulação da medula espinhal como modelo de tratamento da doença de parkinson no primata Callithrix jacchus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Estratégia de vida do peixe anual Hypsolebias antenori (Cyprinodontiformes: Rivulidae) do semiárido brasileiro

This work deals with the life strategy of an endangered annual fish, Hypsolebias antenori (Cyprinodontiformes: Rivulidae), of the Brazilian semiarid region. The eggs of these fish hatch at the onset of the rainy season, grows rapidly and they reproduce during the rainy season. When the water puddles dry out, the entire population dies. The resistant eggs which are buried in the bottom of the dried pools go through diapause stages, during which time the embryonic development becomes temporarily arrested. With the onset of the next rainy season, the eggs hatch and a new generation is formed. Specimens of H. antenori were captured during 2011 and 2013, in temporary water pools located in the hydrographic basin of river Jaguaribe in Ceará, Brazil. Sex ratio, the length-weight relationship, the growth type, first sexual maturity, anatomy and histology of the digestive tract, development of gonads, reproductive strategy, karyotypic pattern of the species, and the conservation status of H. antenori were investigated. The results of this study are presented in the form of eight articles. The first article is about the fish faunal composition of the hydrographic basins of Rio Grande do Norte, Brazil, wherein the record of H. antenori is included. The second article deals with the sex ratio, secondary sexual characteristics of males, the length-weight relationship and the type of growth. Males show a pattern of intense coloration with well developed fins. The sex ratio showed a significant predominance of females (1M:1.7 F). Males were larger in length and weight. The equation of weight and total length relationship was Wt=0.0271Lt3,8937, showing a positively allometric growth, indicating greater increase in weight than in length. The third article discusses the anatomy and histology of the digestive tract of H. antenori. It is considered as a generalist feeder with characteristics of omnivore, which utilizes different food sources. The fourth article discusses the stages and phases of gonad development and type of spawning of H. antenori. The fifth article is about the r reproductive strategy adopted by H. antenori which helps in successful reproduction over a short period of life. The sixth article deals karyotypic pattern of the species, constituting the first cytogenetic contribution to the genus. The seventh article discusses about the risk of extinction of this species which suffers a series of threats, such as, habitat loss through land use, deforestation, construction of reservoirs, pollution due to domestic and industrial sewage, besides pesticides and agrochemicals. Furthermore, decreasing rainfall and intensification of aridity due to global climate changes, interferes with the reproductive cycle. The eighth article deals with aggressive behavior adopted between males and among females during reproduction. All temporary water pools sampled during this study were in high degree of degradation, mainly due to human action. There is a great need for conservation measures to protect the populations of annual fish, including the creation of protected areas in the semiarid ephemeral aquatic environments of Brazil

Ecologia comportamental reprodutiva de Diastatops obscura Fabricius (Insecta, Odonata)

In this thesis I discuss the reproductive behaviour and ecology of the libellulid Diastatops obscura Fabricius, 1775, (Insecta: Odonata) in natural conditions. Populations of this species were studied on the middle stretch of the Pitimbu River, Parnamirim municipality, Rio Grande do Norte, Brazil, during four discontinuous periods between 2002 and 2004. The objectives include the description of strategies and behaviors of both sexes, with especial interest in the intra-male competition for territories and females, the mate selection by females and the importance of male body size and other secondary characters on their reproductive success; from an adaptationist point of view. It was observed that the behavior of males and females in the reproductive areas are interrelated : the males came earlier to compete for the best territories and the females waited the result of that competition to be fertilized by dominants males, which preferably occupied areas near the river margin. The reproductive success of males with territories on the margin, estimated by number of copulations, ovipositions and days acting as territorial, was better than obtained by more separated territorial males and by satellite males. The body size of males is an important factor for the copulation and oviposition taxes and for the number of territorial days, favoring the biggest individuals. I also discuss the apparently importance of wing brilliance and wing integrity on male reproductive success. On inter-sexual relationships, I proved that females of D. obscura participate in mate selection, rejecting non-territorial males or substituting their sperm for other of higher status

Padrão de atividades e de interações sociais de animais juvenis em dois grupos selvagens de Callithrix jacchus

The juvenile period represents the developmental phase between weaning and sexual maturity. Weaning occurs when the youngster does not receive direct care from the caretakers anymore. Individuals in the species Callithrix jacchus live in groups composed by the reproductive pair and successive twin sets. Cooperative care is the rule. Infants are weaned early, and from then on, food is provided by the adults in the group. These animals present high levels of social interactions, through play, grooming and social contact. During infant age, the twin becomes the main partner. There are few studies about the juvenile period, especially on Callithrix gender. The objective of this study was describing the pattern of activities and social interactions of four sets (one single and three twin sets) during juvenile phase in two Callithrix jacchus groups. We used instantaneous and continuous focal sampling for juveniles and scan sampling for adults behavioral recordings. Juveniles presented the same behavioral pattern as the adults relating the activity budget, in particular, foraging along the months. The composition of the diet was the same as that of the adults. Food transfer ended along the juvenile period. Social play as much as grooming were important socializing activities for the juveniles. The young individuals in the group were the main partners in social play, specially the twin. Adults were the main partners in grooming interactions. Scent marking differed between twins in the male/female sets, the female presenting the highest levels of marking. The juveniles were independent from adults in foraging activity. Social interaction varied according to group composition, but in general, interacted more with the twin and with the youngsters (infants and subadults), except in grooming. Even presenting many similarities, juveniles showed some differences between genders, which indicates the differentiation in behavior towards reproductive strategies early in the juvenile period

Implicações do odor na percepção e escolha de parceiro

Why are we attracted to some people but not to other ones? How is this attraction established? Which signs are characteristic of a good partner? These and many other questions concerning how mate attraction and mate selection work out among humans have been intriguing behavioral scientists. It is well-known that beauty indicates something about a potential mate s health. The odor may indicate a similar assessment, if we can assess how pheromones are integrated into human sexual behavior. However, what is the relation between age preference and body scent evaluation? In order to investigate this question, this study´s objective was identifying evidences which show that olfactory cues might reveal the potential mate s age and that it coincides with the ideal mate s profile. To produce the stimuli, men and women had to wear cotton t-shirts for three nights in order to have their body odor impregnated. After that, opposite-sex individuals evaluated the intensity and attractivity of these odor impregnated tshirts according to two Likert scales (4 points scale for intensity; 7 points scale for attractivity). We found differences between men and women on body scent perception, that indicates a better scent discrimination for women when it concerns the perception of potential mate s age. Another finding was the negative correlation between intensity and attractiveness perception for both sexes. We also verified that mate selection strategies are plural, more than one tactic simultaneously fitting in the same strategy, but all of them are related to differential investment of each sex on their own reproductive success

Aprendizado espacial-temporal em um ambiente complexo sem restrição alimentar em ratos

Timeplace learning is the capacity of organisms to associate both space and time with a biological relevant stimulus such as food. Experiments are usually done with food restricted animals due to the belief that food system activation is necessary for timeplace learning. Another line of thought suggest that, in addition to food system activation, response cost should be increased to effectively allow timeplace discrimination. The purpose of this experiment was to test whether a complex environment, which presumably implied in a heightened response cost, would facilitate timeplace association in satiated rats using a highly palatable food as reward. Nine rats were trained in a timeplace task for 30 nonconsecutive days. A large experimental box (1x1m) divided in four compartments was used. To access each compartment the animal had to overcome a series of obstacles such as ramps, staircases and mazes. Two feeders localized in opposite compartments were rewarded with sunflower seeds in two daily sessions. One feeder offered the reward during the morning sessions while the second feeder in afternoon sessions. After the 15th day of training, the animals began to show a preference for the correct feeder during the correct time of day expressed by increased frequency of visits as well as lower latency to access the feeders. These results suggest that satiated animals are also capable of learning a timespace task as far as the experimental context is complex enough to result in a higher response cost

Comportamento de parâmetros fisiológicos de homens e mulheres em condições de estresse laboral submetidos à técnica Watsu

The physiological variations of parameters in situations of laboral stress can function like indicator in the sprouting of disorder. Those conditions have led researchers to investigate alternatives that can favor the quality of life in persons under stress laboral. The present research had as objectives investigate the physiological behavior of parameters (blood pressure, heart hat and respiratory hat) of men and women in condition of stress laboral submitted to the technique Watsu. It was used a experimental methodology with a group formed by men and women in reproductive age, that work as salesclerk in a supermarket net in Natal/RN. The seven individuals selected were submitted to the three phases of the study (dependent groups), that consisted of the phase 1 of obtaining from the measure basal (control 1), in the phase 2 of immersion in the water (control 2), and phase 3 from the application the technique Watsu (experimental phase). It was verified that during the phase basal (condition 1) the physiological parameters (BPS, BPD, HH and RH) of both sexes evaluated showed the medium values of the women (average±detour-standard: BSP = 104.1±7.92; BPD = 70.83 ±7.92; HH = 77.58 ±3.87; RH = 19.83 ±2.58) similar those presented by the men (BPS = 118.75 ±7.55; BPD = 75.00 ±9.91; HH = 71.75 ±14.95; RH = 16.62 ±3.99). The evaluation of those parameters before and after immersion of the volunteers in the water (condition 2) showed a significant reduction (W = 3.0: p≤0.05) barely for the values of BPS presented by the sex females after immersion. In the men group, all of the physiological parameters analyzed did not vary significantly. Regarding the profile of those variables before and after application of the watsu (condition 3), was verified a significant increase (W= 0,0: p≤0.05) for the BPS one and SABP in the women. The Men did not show significant variation for all of the physiological parameters. Faced with the results presented, we are able to conclude that the systolic and diastolic blood pressures were the physiological parameters that are on influence from the Technique Watsu, only for the kind females

As competições sociais em grupos de Callithrix jacchus (Callitrichidae, Primates) são influenciadas pelo parentesco e pela convivência?

The Callitrichidae family is characterized by flexibility in its mating system, being possible to find monogamous, polyandrid and polygynic groups. Its social organization and mating system can be defined by the interaction between ecological and demographic factors plus the degree of relatedness among the individuals in the population. The objective of this work was to demonstrate the influence of relatedness and coexistence on the establishment and maintenance of social relations between Callithrix jacchus adult males. Four pairs of related adult males (CP), 4 pairs with coexistence between the animals in the pair (CC) and 4 pairs with no relatedness (SP) were studied. The pairs in the group CC had been kept in the same cage for at least 8 months before the experiment and the pairs in the group SP were put together at the beginning of the study. Each animal was observed 3 times/week for 2 months, in 15 min. sessions, through focal time sampling with instantaneous record each minute. In the first month, only the pair of males was kept in the cage (Phase I) and in the second month, a female was introduced into the cage (Phase II). The affiliative, agonistic and sexual interactions were registered. Affiliative interactions showed similar frequencies for all groups in phases. There was also no significant difference in the agonistic interactions of the CP, CC and SP males in Pase I, even considering that group SP exhibited higher levels of agonism. In Phase II, there was a statistically significant increase comparing to the others. The results demonstrate that relatedness and coexistence are of great importance for maintaining reprodutive and social stability inside the group. Nonetheless, in this study, only one of the males in the pair had sexual interations with the females, except for 2 pairs. This was assured through mate guarding and agonism directed to the potencial competitor. The most probable mating system would be functional monogamy, where the males would present low levels of competition, if there is relatedness and coexistence among them; on the other hand, a strong competition if there is no relatedness between the individuals. Even so, a polyandric system would also have to be considered

Efeitos da alteração dos níveis de ansiedade no desempenho de ratos em uma tarefa de discriminação apetitiva

The plus-maze discriminative avoidance paradigm has been used to study the relationship between aversive memory and anxiety. The present study aims to verify if the elevated plus-maze can provide information about appetitive memory and anxiety, through a task motivated by food reward. Animals were allowed to explore an elevated plus-maze and received reinforcement in one of the enclosed arms. In a test session performed 24h later, in the absence of reward, rats showed preference for the previously rewarded enclosed arm over the neutral enclosed arm. The administration of diazepam and pentylenetetrazole before training induced, respectively, anxiolytic and anxiogenic effects (as evaluated by open-arm exploration). Both drugs induced amnestic effects, i.e., lack of preference for the rewarded arm in the test session. The results suggest that appetitive memory can be influenced by anxiety levels as well. The plus-maze appetitive discrimination task seems to be a useful model to investigate the relationship between memory and anxiety

Efeitos de vocalizações de co-específicos e do escuro sobre o ritmo circadiano da atividade motora em sagüis (Callithrix jacchus)

The principal zeitgeber for most of species is the light-dark photocycle (LD), though other environment factors as food availability, temperature and social cues may act. Daily adjustment of the circadian pacemaker may result from integration of environmental photic and non-photic cues with homeostatic cues. Characterization of non-photic effects on circadian timing system in diurnal mammals is scarce in relation to nocturnal, especially for ecologically significant cues. Thus, we analyzed the effect of conspecific vocalizations and darkness on circadian activity rhythm (CAR) in the diurnal primate Callithirx jacchus. With this objective 7 male adults were isolated in a room with controlled illumination, temperature (26,8 ± 0,2°C) and humidity (81,6 ± 3,6%), and partial acoustic isolation. Initially they were under LD 12:12 (~300:2 lux), and subsequently under constant illumination (~2 lux). Two pulses of conspecific vocalizations were applied in total darkness, separated by 22 days, at 7:30 h (external time) during 1 h. They induced phase delays at circadian times (CTs) 1 and 10 and predominantly phase advances at CTs 9 and 15. After that, two dark pulses were applied, separated by 14 days, during 1 h at 7:30 h (external time). These pulses induced phase delays at CTs 2, 3 and 18, predominantly phase advances at CTs 8, 10 and 19, and no change at CT 14. However, marmosets CAR showed oscillations in endogenous period and active phase duration influenced by vocalizations from animals outside the experimental room, which interfered on the phase responses to pulses. Furthermore, social masking and relative coordination with colony were observed. Therefore, phase responses obtained in this work cannot be attributed only to pulses. Afterwards, pulses of conspecific vocalizations were applied in total darkness at 19:00 h (external time), during 1 h for 5 consecutive days, and after 21 days, for 30 consecutive days, on attempt to synchronize the CAR. No animal was synchronized by these daily pulses, although oscillations in endogenous period were observed for all. This result may be due to habituation. Other possibility is the absence of social significance of the vocalizations for the animals due to random reproduction, since each vocalization has a function that could be lost by a mixture of sounds. In conclusion, conspecific vocalizations induce social masking and relative coordination in marmosets CAR, acting as weak zeitgeber

Déficits de memória induzidos por baixas doses de reserpina em ratos: possível relação com prejuízos no processamento emocional na Doença de Parkinson

We have recently verified that the monoamine depleting drug reserpine at doses that do not modify motor function - impairs memory in a rodent model of aversive discrimination. In this study, the effects of reserpine (0.1-0.5 mg/kg) on the performance of rats in object recognition, spatial working memory (spontaneous alternation) and emotional memory (contextual freezing conditioning) tasks were investigated. While object recognition and spontaneous alternation behavior were not affected by reserpine treatment, contextual fear conditioning was impaired. Together with previous studies, these results suggest that mild monoamine depletion would preferentially induce deficits in tasks involved with emotional contexts. Possible relationships with cognitive and emotional processing deficits in Parkinson disease are discussed