The major purpose of the study was to examine mood fluctuations associated with phases of the menstrual cycle. To assess the relative impact of the menstrual cycle on moods, other cycles hypothesized to influence moods also were assessed. Mood fluctuations in women and men were studied both prospectively and retrospectively to determine whether cyclic changes occur with the phases of the menstrual cycle, lunar cycle, and/or days of the week. Each participant (15 women using oral contraceptives, 12 normally cycling women, and 15 men) recorded their moods daily for 70 days (prospective data). A daily mean score was obtained for both pleasantness and arousal (each on a 9-point positive to negative scale). Mood stability/variability was recorded daily on a 4-point scale. At the end of the study, participants recalled (retrospective data) their mood over the previous 2 months for each day of the week and the phases of their menstrual cycle (women only). The focus on menstrual cycles was sucessfully camouflaged. Prospectively, there were no group differences and no menstrually-related mood fluctuations. The retrospective reports, however, indicated systematic bias. Women recalled more positive moods in the follicular phase and more negative moods in the premenstrual and menstrual phases than they had reported prospectively. All groups reported weekday mood changes — Monday lows and Friday/Saturday highs. Recollections of weekday mood fluctuations were similar to but more exaggerated than prospective reports. Prospective reports revealed no mood fluctuations over the lunar cycle. Together, these results indicate that stereotypes (both well- and ill-founded) influence recollections of mood, and are consistent with schematic processing theories. The importance for menstrual cycle research of obtaining information about positive as well as negative experiences, camouflaging the purpose of the study, collecting prospective data, and assessing results in the contexts of other cycles also is discussed. / Arts, Faculty of / Psychology, Department of / Graduate

Critical life history events such as breeding, migration and hibernation must take place in the correct environmental context to minimize deleterious consequences on survival and reproductive fitness. Neuroendocrine mechanisms synchronizing internal physiological states with extrinsic environmental cues are vital to timing life history events appropriately. Secretion of the pineal hormone melatonin is sensitive to light and temperature cues, which provides a physiological indicator of time of day and time of year for organisms. Melatonin influences seasonal reproduction in a variety of vertebrates, likely by altering the synthesis and/or release of reproductive neuropeptides in the brain. The neuropeptides arginine vasotocin and its mammalian homologue, arginine vasopressin, are well-known modulators of reproductive and sociosexual behavior across vertebrate taxa, and are likely targets of melatonin in the context of seasonal reproduction. There is extensive evidence that vasotocin/vasopressin innervation in the brain is subject to seasonal variation, and that this variation is frequently sexually dimorphic. However, evidence that melatonin directly modulates this important neuropeptide system is lacking. Melatonin receptor 1a (MT1 in mammals) may be responsible for mediating melatonin's influence on brain vasotocin, as it is known to regulate seasonal reproduction in a variety of vertebrates. In the present study, I asked whether melatonin influences brain vasotocin in male green treefrogs (Hyla cinerea), and compared the distribution of melatonin receptor 1a in the brain of green treefrogs between sexes and seasons. Adult male and female green treefrogs were collected from field sites in Louisiana during the summer breeding season. Summer animals were acclimated to lab conditions for 3 weeks, then euthanized and their brains collected. Winter animals were maintained in the lab for four months under incrementally changing photo-, thermo-, and hygroperiod regimes that mimicked the transition to winter in their natural habitat, followed by euthanasia and brain collection. A subset of winter males (Experiment 1) were implanted with melatonin-filled or blank silastic capsules for a period of one month prior to euthanasia and brain collection. Brains of these males were processed for vasotocin immunohistochemistry. I quantified AVT-ir cell number in Experiment 1 males in the nucleus accumbens (NAcc), amygdala and caudal striatum (AMG), preoptic area (POA), suprachaismatic nucleus (SCN), and ventral hypothalamus (VH). Melatonin did not influence brain vasotocin-ir cell number in any brain region. Brains from untreated summer and winter males and females were collected and processed for MT1 immunohistochemistry. MT1-ir cells were quantified in the NAcc, striatum (STR), AMG, POA, SCN, and VH. In all regions quantified, reproductively active males had significantly more MT1-ir cells than nonreproductive males. Within the summer breeding season, males had significantly more MT1-ir cells in the NAcc than did reproductively active females. In all other regions there was no significant difference in MT1-ir cell number between reproductively active males and females. Collectively, these data suggest that melatonin modulates vasotocin via MT1. These findings assist in elucidating the neuroendocrine mechanisms by which vertebrates integrate seasonal cues with physiology to correctly time critical life history events.

This thesis presents research investigating the relationship between, and methods of, measuring circadian rhythms in mood disorders in a population of currently depressed and euthymic individuals with both depression and bipolar disorder. This was first assessed by comparing group differences in subjective sleep and circadian measures with objective sleep and circadian measures. The objective circadian measures involved actigraphy and melatonin profiling. This analysis showed group differences in subjective sleep and circadian parameters compared to controls, however no robust differences between mood groups. Objective melatonin profiling showed a mild agreement with subjective circadian parameters. Next, we studied the external validity of a subjective rating scale measuring biological rhythm disturbance, the Biological Rhythms Interview for Assessment in Neuropsychiatry (BRIAN), against objective measures of sleep and circadian activity rhythmicity. The BRIAN demonstrated some promising external validity, namely correlations with wake after sleep onset (WASO) and sleep efficiency, as well as melatonin levels in each group. These studies provide evidence of the extent to which a self-report may help in assessing parameters of sleep and circadian rhythms in the clinical setting. In doing so, it is expected that the use of subjective ratings will provide insight into the impact of biological rhythms disturbances and mood disorders. Lastly, we conducted an overview of the preclinical and clinical literature investigating the impact of circadian disturbance on cognitive performance. The results from this literature review yielded patterns of rhythmicity in specific parameters in each of the attention, memory, and executive function domains in humans, whereas attention and memory are more of a primary focus in animal studies. However, we also found that there are significant gaps in the understanding of how disturbances in circadian rhythms may influence cognitive function. This review also highlights the importance of cross-species translational validity from a methodological perspective, in order to generate positive clinical results beginning at the preclinical stage in neuropsychiatric disorders. / Thesis / Master of Science (MSc)

O dinoflagelado unicelular marinho fotossintetizante Gonyaulax polyedra tem sido utilizado como modelo para o estudo de relógios biológicos. Neste organismo já foram descritos os ritmos de: migração vertical, divisão celular, atividade de superóxido dismutase e nitrato redutase, bioluminescência e capacidade fotossintética. Investigamos a variação circadiana dos pigmentos carotenóides e de RuBisCo II e PCP, as quais estão intimamente ligadas ao processo fotossintético. Experimentos de supressão de espécies reativas de oxigênio (EROs) por carotenóides foram preparados e mostraram que extratos de carotenóides de G. polyedra são capazes de suprimir o O2(1Δg) (oxigênio singlete) in vitro confirmando o importante papel destes no controle das EROs nestas algas. Os extratos metanólicos apresentaram vários pigmentos, tais como clorofila a, β-caroteno e peridinina em diferentes concentrações. A peridinina representa 80 % do total de carotenóides enquanto que o β-caroteno somente 4%. As análises dos cromatogramas de HPLC mostraram que a razão peridinina/clorofila a não varia ao longo de 24 h porém, por outro lado, o β-caroteno apresenta uma variação significativa na sua quantidade, com níveis duas vezes maiores no meio do dia em comparação com os níveis no meio da noite. Esta variação é conservada mesmo quando as células são mantidas em condições de luz constante. A curva de dose-resposta para a síntese de β-caroteno induzida pela luz mostra uma resposta linear com 45 minutos de exposição a luz branca. A indução é máxima quando utilizamos as células do meio período da noite (CT 18) que após esta exposição apresentam níveis de β-caroteno semelhantes as células do meio do dia. Esta alteração de fase no CT 18 sugere que este pigmento pode ser um dos compostos-captadores de luz envolvidos no mecanismo de ajuste de fase por luz em G. polyedra. Culturas de G. polyedra do meio da noite foram expostas à diferentes irradiações (azul, vermelha e verde) e os seus pigmentos extraídos e analisados. Em outra série de experimentos, as células foram mantidas durante o período de claro (12: 12 h) sob diferentes irradiações (vermelha, verde e azul) por 36 horas e os seus pigmentos analisados. Os resultados sugerem que a síntese foto-induzida e a oscilação circadiana do β-caroteno estão ligadas a um fotorreceptor de luz azul/ verde. Nas condições utilizadas não foram observadas variações significativas no conteúdo protéico da RuBisCo II e da PCP ao longo do dia. As análises de RNA total da RuBisCo II mostram que não há variação nos seus níveis quando as células são coletadas no meio do dia e no meio da noite. Quando expostas a condições adversas, G. polyedra apresenta a capacidade de encistar. Embora se conheça bem este mecanismo de defesa, existem poucas informações sobre o estado fisiológico destas células. Células encistadas induzidas por dias curtos apresentam uma alteração na composição de pigmentos com diminuição nas quantidades de β-caroteno e de clorofila a e aumento da quantidade de peridinina, indicando um rearranjo do aparato fotossintético nesta situação, com a peridinina desempenhando um papel mais estrutural. Em consequência, embora o conteúdo protéico de RuBisCo permaneça inalterado, os níveis protéicos de PCP se encontram diminuídos nas células encistadas. / Gonyaulax polyedra, a marine dinoflagellate which has been used as a model to study the biological clock, displays numerous circadian processes, such as bioluminescence, cell aggregation, cell division, superoxide dismutase and nitrate reductase activities and photosynthesis. In this alga, the photosynthesis is maximal in the middle of the day and minimal in the middle of the night. We investigated the pigments content and the amounts of two proteins related to the photosynthesis: ribulose- 1,5- bisphosphate carboxylase/ oxygenase form II (RuBisCo II) and peridinin: chlorophyll a: protein (PCP) in a 24 h cycle. Using the thermal decomposition of 1,4-dimethylnaphtalene endoperoxide, it was shown that the carotenoids could act as effective quenchers of synglet oxygen in G. polyedra. G. polyedra pigments were extracted every three hours over 24 hours. The amounts of peridinin and chlorophyll a remain constant over the day while the levels of β-carotene oscillate, being two times higher at the day than at the night phase. This variation persists when the cells were kept under constant dim light. The dose-response curve for light-induced β-carotene synthesis showed a linear response up to 45 minutes of light exposure, after which night-phase cells contained the same levels of β-carotene as day-phase cells. Cells exposed to light pulses at different times displays the highest β-carotene induction in the middle of the night. This may suggest that β-carotene may be one of the light-harvesting compounds involved in the light induced phase-shift in Gonyaulax polyedra. To identify which was the photoreceptor involved in β-carotene synthesis, cell of the middle of the night-phase (CT 18) were exposed for 45 minutes to different irradiations (red, blue and green) and their pigments extracted and analysed. Also, cells were grown under red, blue and green light during the light phase (12 h light: 12 h dark ) for 36 hours and their pigments analysed. The results suggested that the circadian oscillation and the photoinduced response synthesis of β-carotene, are related to a blue light receptor. The amounts of RuBisCo II and PCP do not change over the circadian cycle when the cultures were grown under constant dim light. The levels of these proteins also remain constant when cells were kept under ither white light or different light qualities (red, blue and green ) in light: dark (12: 12 h) regime. The G. polyedra RuBisCo form II transcrits levels are the same in middle-day and middle-night cells, suggesting a post-translational control for this enzyme in this organism. Adverse environmental conditions elicit the encystment of G. polyedra. Our results showed an alteration in pigment composition of cysts. An increase in peridinin levels and a decrease in β-carotene and chlorophyll a content were observed. Although RuBisCo form II protein levels remained constant, there was a reduction in the amounts of PCP in cysts. This suggests an important role in thylakoids structure stabilizer for free peridinin.

Nos mamíferos os núcleos supraquiasmáticos regulam os ritmos circadianos do organismo. A melatonina, hormônio da glândula pineal, é um importante regulador dos ritmos de atividade motora (AM) e temperatura corporal (TC), sendo a sua produção influenciada pelo diabetes mellitus tipo I (DM1). Foram avaliados os efeitos do DM1 sobre os ritmos de TC e AM, seus parâmetros rítmicos, peso e glicemia, assim como as modificações pelos tratamentos tardios e precoces com insulina, melatonina ou ambos. O diabetes rompeu o ritmo de TC, alterou o ritmo de AM, e reduziu a TC e AM. Os tratamentos INS e INS+MEL reverteram o quadro. MEL restaurou apenas alguns parâmetros rítmicos, sendo mais eficiente sobre a AM. Esses resultados mostram que o DM1 altera os ritmos de TC e AM. Os tratamentos INS e INS+MEL revertem o quadro, sendo INS+MEL mais eficiente. A MEL atenua os efeitos deletérios, sendo mais evidente na AM. A insulina é mais rápida, mais duradoura e mais eficiente que a melatonina, que age melhor sobre a AM, e essas melhoras dependem da continuidade dos tratamentos. / In mammals the suprachiasmatic nuclei regulate the circadian rhythms of the body. Melatonin, the pineal gland hormone, is a major regulator of the body temperature (BT) and home cage activity (HCA) rhythms. Its production is influenced by type 1 diabetes mellitus (T1DM). The present work studied the effects of T1DM on BT and HCA rhythms, its rhythmic parameters, glycaemia and body weight and the modifications resulting from early and late treatment with insulin, melatonin or both, in rats. Diabetes disrupted the BT rhythm, altered HCA rhythm, and led to hypothermia and reduced HCA. Late INS and INS+MEL reverted to normal. MEL restored some rhythmic parameters, being more evident on HCA. Taken together, T1DM alters BT and HCA rhythms. INS and INS+MEL treatments revert to normal, being INS+MEL more efficient. MEL attenuates the diabetic state, being more evident on HCA. Insulin effects are faster, last longer and are more efficient than melatonins, which are more evident on HCA, and these beneficial effects depend on the maintenance of the treatments.

Os comportamentos coletivos observados em colônias de insetos eussociais muitas vezes podem ser explicados apenas pelo comportamento dos indivíduos que compõe a colônia. De fato, em muitas condições essa previsão se concretiza. Em outras condições o comportamento individual apenas não explica o comportamento coletivo. Atualmente sabe-se que vários fatores individuais, sociais e ambientais influenciam no comportamento que indivíduos, mesmo que de carga genética idêntica, irão apresentar. A divisão de tarefas observada nas colônias de insetos eussociais é um exemplo de como indivíduos semelhantes morfológica e geneticamente adotam comportamentos diferentes dependendo de inúmeros fatores inerentes à organização social. A relação entre o comportamento dos indivíduos e as condições ambientais é intima, principalmente em relação às condições cíclicas. Inclusive existe um sistema fisiológico nos organismos que marca essa relação entre o comportamento e o tempo. Espera-se que cada indivíduo de uma colônia de insetos eussociais esteja munido desse aparato e que eles sejam semelhantes. Entretanto, em saúvas essa relação entre comportamento e ritmos ambientais se apresenta de maneira confusa. A colônia é noturna, com a maior atividade de suas operárias ocorrendo à noite, entretanto, vários indivíduos são vistos na fase de claro. Ou as forrageadoras são arrítmicas e podem forragear em qualquer fase do dia, ou as formigas se dividem em turno de trabalhos. A presente dissertação tem por objetivo descrever a existência de divisão temporal de tarefas em formigas saúvas. Foram marcadas formigas em diferentes fases (claro e escuro) e turnos (horários específicos) e observou-se a distribuição do engajamento dessas formigas marcadas na tarefa de forrageamento ao longo de cinco dias nessas diferentes fases e turnos. Foi medido também o tamanho das formigas que foram observadas em claro e em escuro e a relação entre a atividade da colônia e a eficiência na coleta de alimento Os resultados indicam que as formigas de fato dividem temporalmente a tarefa de forrageamento. Formigas de claro e formigas de escuro constituem grupos distintos, que forrageiam preferencialmente no mesmo horário. Além disso, essa divisão apresenta forte correlato com a morfologia, formigas de claro são maiores que formigas de escuro. Aparentemente essa divisão temporal de tarefa acarreta em implicações para a eficiência de forrageamento. No claro, apesar de o número de formigas observadas ser menor, a eficiência na coleta de alimentos é maior do que no escuro. A relação observada entre a morfologia e a divisão temporal de tarefas pode ser explicada pela relação de resistência às condições ambientais. Formigas maiores tendem a ser mais resistentes a temperaturas mais elevadas. Como a incidência solar e a temperatura é maior no claro, faz sentido que exista essa divisão. Entretanto, resta saber quais mecanismos fisiológicos podem gerar indivíduos geneticamente semelhantes, mas que se relacionam de maneira diferente com as condições cíclicas do ambiente / The collective behavior observed in social colonies can be explained by the behavior of its individuals, most of the time. Thus, it is expected that all workers should display the same behavior. Indeed, this prediction is fulfilled in many cases. However, many collective behaviors cannot be explained only by individual behaviors. Nowadays it is known that many individual, social and environmental conditions modulate the individual, and consequently, the collective behavior. The division of labor observed in social colonies is an example of different behaviors displayed by similar individuals reared in different conditions. Behavior and environmental conditions are closely related, especially regarding the cyclic conditions. A physiological system whose function is modulate behavior concerning time was described. It is expected that each individual in a social colony bear this system and that they mark the same relationship. However, in leaf-cutting ants this system and the relationship between behavior and cyclic conditions appear to be more complex. The colony is nocturnal, because the main worker activity time happens at night; however, there is a significant amount of ants observed at day. Or the workers are arrhythmic and are able to forage at any time, or they divide the labor in work shifts. This dissertation aims to describe the process of temporal division of labor in leaf-cutting ants. Workers of leaf-cutting ants were marked in different phases (dark and light) and shifts (specific time windows). This marked ants engagement in foraging was observed along five days on the same phases and shifts. Light and dark ants body size was measured as well as the correlation between colony activity and the food retrieval efficiency. The results show that leaf-cutting ants indeed divide the labor in work shifts. Light ants and dark ants establish distinct groups. Additionally, there is difference in the ant body size of those groups: light ants are bigger than dark ants. It seems that the temporal division of labor implies in food retrieval efficiency differences. Although the fewer ants in the light phase, the food retrieval is bigger in light than in dark. The relationship between morphology and temporal division of labor can be explained by the difference in thermal tolerance of different ant body size. Bigger ants can withstand higher temperature than smaller ants. It makes sense, day temperature is higher than night\'s. Hence, the process and physiological mechanisms that generate genetically similar workers whose relation to light-dark cycles is different remains to be studied

INTRODUÇÃO Este é um estudo sobre os horários escolares e sua relação com o cotidiano dos professores e os possíveis impactos que a homogeneização de horários e a realização das atividades podem exercer sobre seus ritmos biológicos. Os horários escolares podem afetar as rotinas diárias dos professores, induzindo a dessincronização dos ritmos biológicos e consequentes problemas de saúde. Entre esses problemas, as alterações no ciclo vigília/sono são as mais conhecidas. HIPÓTESE Esses conflitos podem levá-los a privações de sono e uma dessincronização de seus ritmos biológicos, obrigando-os a uma espécie de enquadramento dentro do sistema imposto, mas com riscos à sua saúde. OBJETIVO Avaliar a adaptação dos professores aos horários escolares, associando suas preferências de tolerância à maturidade ao grau de satisfação com suas condições de trabalho. MÉTODOS Foram estudados 25 professores (4 homens e 21 mulheres) com idades entre 28 e 49 anos, que trabalham em duas escolas públicas da região metropolitana de São Paulo. Foram aplicados os seguintes instrumentos: diário de atividades diárias (23 dias consecutivos), Escala de Sonolência de Karolinska (dois pontos, início da tarde e início da noite), preferências de matutinidade-vespertinidade com questionário de Horne e Östberg, Questionário Satisfação no Trabalho e entrevistas com grupos focais. RESULTADOS: A análise dos dados da Escala de Karolinska mostrou que nos finais de semana houve uma variação da sonolência ao longo do dia [F(3,66) = 5,1; p < 0,01]. As comparações mostraram que a sonolência média dos professores avaliada às 13:33 ± 1,4 horas (KSS=4,2 ±1,95) e às 17:40 ± 1,25 horas (KSS=4,6±1,32) foi menor em relação às 21:35 ± 1,14 horas (KSS=5,9 ± 2). Nos dias de semana não foi observada nenhuma diferença [F(3,66) - 2,01; p>0,05]. Com os resultados do Questionário OSI, podemos perceber que o índice de insatisfação foi mais acentuado nos quesitos remuneração, participação nas decisões e quantidade de tarefas; e o de satisfação, os mais significativos foram relacionamento e conteúdo. Ficaram evidenciados ainda, má qualidade do sono nos professores caracterizados como vespertinos, devido ao horário de trabalho em relação com os matutinos. Ficou relatada alimentação inadequada devido aos deslocamentos e horários irregulares de trabalho, além da dificuldade em ajustar os horários de trabalho com suas relações sociais. CONCLUSÃO Os horários escolares influenciam na organização temporal dos professores, afetando seu sono, saúde e qualidade de vida / INTRODUCTION This is a study about the school schedules and their relationship with teachers\' daily life and the possible impacts that the homogenization of schedules and the accomplishment of activities can influence their biological rhythms. School schedules may affect daily routines of teachers, inducing desynchronization of biological rhythms and consequent health problems. Among these problems, changes in the sleep/wake cycle are the best known. HYPOTHESIS These conflicts can lead to sleep deprivation and a desynchronization of their biological rhythms, forcing an adaptation to the work schedule in turn may compromise their heal condition. OBJECTIVE Evaluate adaptation of teachers to school schedules linking their morningness-eveningness preferences to degree of satisfaction with their work conditions. METHODS We studied 25 teachers (4 males and 21 females) aged 28-49 years old, working at two public school in the metropolitan area of São Paulo. The following instruments were applied : daily activities diary (23 consecutive days), Karolinska Sleepiness Scale (at two ponts, early afternoon and early evening), Morningness-eveningness preferences with the Horne and Östbergs questionnaire, Satisfaction at work questionnaire and focal group interviews. RESULTS Data analysis of the Karolinska Scale showed that at weekends there was a variation of sleepiness throughout the day [F (3.66) = 5.1; p <0.01]. The Comparisons showed that the mean teacher drowsiness assessed at 13:33 ± 1,4 hours (KSS = 4,2 ± 1,95) and at 17:40 ± 1.25 hours (KSS = 4,6 ± 1,32 ) was lower in relation to 21:35 ± 1,14 hours (KSS = 5,9 ± 2). On weekdays no difference was observed [F (3,66) = 2,01; p> 0,05]. The OSI Questionnaire showed that the dissatisfaction was more pronounced in terms of remuneration, participation in decisions and quantity of tasks; and satisfaction, the most significant were relationship, content, poor quality of sleep was still evident in the teachers characterized as evening because of the morning work schedule in relation to the morning ones. Evening oriented teachers show worse sleep quality than their morning-oriented colleagues. Inadequate feeding routines linked to irregular working schedules as well as compromised social relations have been found in our sample. CONCLUSION: School schedules influence temporal organization of teachers affecting their sleep, health and quality of life

O metabolismo energético é dependente, dentre outros fatores, de uma temporização circadiana entre os tecidos participantes da regulação metabólica. O processo de sincronização parece depender da expressão dos genes relógio e de mediadores como a melatonina, que associam o oscilador central e os osciladores periféricos. Investigamos o papel da melatonina na expressão dos genes relógio em tecidos periféricos, onde ratos Wistar foram divididos em dois grupos: pinealectomizados e controle. Após 45 dias os animais foram sacrificados circadianamente e seus tecidos de interesse extraídos para análise através do PCR convencional. A pinealectomia ocasionou significativa desorganização temporal na expressão de quase todos os genes relógios dos tecidos muscular e do adiposo periepididimal. O tecido hepático foi o que menos sofreu alterações pela pinealectomia. Em conclusão, esses dados mostram que a melatonina é necessária para manutenção da ritmicidade dos genes relógio no tecido muscular estriado esquelético, no tecido adiposo periepididimal e no tecido hepático. / The energy metabolism is dependent, between other factors, of a circadian timing among the tissues participants of the metabolic regulation. The synchronization process appears to depend on the expression of clock genes and mediators such as melatonin, involving the central oscillator and peripheral oscillators. We have investigated the role of melatonin in the expression of clock genes in peripheral tissues. Rats have been divided into two groups: pinealectomized and control rats. After 45 days the animals were sacrificed and their tissues of interest have been extracted for analysis by conventional PCR. Pinealectomy caused a significant disruption in the temporal expression of almost all genes of muscle tissue and fat tissue. The liver tissue was the least affected by changes of pinealectomy. In conclusion, these data show that melatonin is necessary for maintaining the rhythmicity of clock genes in skeletal muscle, adipose tissue and liver tissue.

O núcleo supraquiasmático (NSQ), principal relógio biológico circadiano em mamíferos, contem população variada de neurônios produtores de diferentes substâncias neuroativas. Em roedores, as pesquisas avançaram na investigação dos mecanismos moleculares e substâncias neuroativas, que em conjunto determinam a função do relógio biológico. Entretanto, há poucas informações em espécies diurnas, especialmente primatas sobre esta organização intrínseca que não raramente apresenta diferenças nas espécies estudadas. O presente estudo busca identificar a natureza química dos principais grupamentos neuronais do NSQ no primata diurno Cebus apella, relacionando a localização destes grupamentos com as três principais projeções aferentes deste núcleo. Os resultados obtidos evidenciam organização complexa do NSQ, caracterizada por grupos celulares contendo vasopressina, polipeptídeo intestinal vasoativo e marcador de diferenciação neural com localização semelhante a de roedores e células que contém calbindina e calretinina com localização diferente da de roedores. / The suprachiasmatic nucleus (SCN), the main circadian clock in mammals, contains diverse population of neurons of different neuroactive substances. In rodents, there has been extensive research in the recent past looking into the molecular basis and mechanisms of the biological clock. However, there is little information in diurnal species, especially primates about this organization seldom has no intrinsic differences in the species studied. This study seeks to identify the chemical nature of the main groups of SCN neurons in diurnal primate Cebus apella, relating the location of these groups with the three major afferent projections from this nucleus. The results show complex organization of the SCN, characterized by cell groups containing vasopressin, vasoactive intestinal polypeptide and neuronal differentiation marker in the same location and rodent cells that contain calbindin and calretinin with location different from that of rodents.

Working memory (WM) is a process that allows for the temporary and limited storage of information for an immediate goal or to be stored into a more permanent system. A large number of studies have led to the widely accepted view that WM is mediated by the frontoparietal network (FPN), consisting of areas in the prefrontal cortex (PFC) and posterior parietal cortex (PPC). Current evidence suggests that task specific patterns of neuronal oscillatory activity within the FPN play a fundamental role in WM, and yet specific spatio-temporal properties of this activity are not well characterized. This study utilized multisite local field potential (LFP) data recorded from PFC and PPC sites in two macaque monkeys trained to perform a rule-based, Oculomotor Delayed Match-to-Sample task. The animals were required to learn which of two rules determined the correct match (Location matching or Identity matching). Following a 500 ms fixation period, a sample stimulus was presented for 500 ms, followed by a randomized delay lasting 800-1200 ms in which no stimulus was present. At the end of the delay period, a match stimulus was presented, consisting of two of three possible objects presented at two of three possible locations. When the match stimulus appeared, the monkey made a saccadic eye movement to the target. The rule in effect determined which object served as the target. Time-frequency plots of three spectral measures (power, coherence, and Wiener Granger Causality (WGC) were computed from MultiVariate AutoRegressive LFP time-series models estimated in a 100-ms window that was slid across each of three analysis epochs (fixation, sample, and delay). Low (25- 55 Hz) and high gamma (65- 100 Hz) activity were investigated separately due to evidence that they may be functionally distinct. Within each epoch, recording sites in the PPC and PFC were classified into groups according to the similarity of their power t-f plots derived by a K-means clustering algorithm. From the power-based site groups, the corresponding coherence and WGC were analyzed. This classification procedure uncovered spatial, temporal, and frequency dynamics of FPN involvement in WM and other co-occurring processes, such as sensory and target related processes. These processes were distinguishable by rule and performance accuracy across all three spectral measures- power, coherence, and WGC. Location and Identity rule were distinguishable by the low and high-gamma range. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection