The indirect amygdala-dorsal striatum pathway mediates conditioned freezing: Insights on emotional memory networks

The dorsal striatum (DS) is involved in various forms of learning and memory such as procedural learning, habit learning, reward-association and emotional learning. We have previously reported that bilateral DS lesions disrupt tone fear conditioning (TFC), but not contextual fear conditioning (CFC) [Ferreira TL, Moreira KM, Ikeda DC, Bueno OFA, Oliveira MGM (2003) Effects of dorsal striatum lesions in tone fear conditioning and contextual fear conditioning. Brain Res 987:17-24]. To further elucidate the participation of DS in emotional learning, in the present study, we investigated the effects of bilateral pretest (postraining) electrolytic DS lesions on TFC. Given the well-acknowledged role of the amygdala in emotional learning, we also examined a possible cooperation between DS and the amygdala in TFC, by using asymmetrical electrolytic lesions, consisting of a unilateral lesion of the central amygdaloid nucleus (CeA) combined to a contralateral DS lesion. The results show that pre-test bilateral DS lesions disrupt TFC responses, suggesting that DS plays a role in the expression of TFC. More importantly, rats with asymmetrical pre-training lesions were impaired in TFC, but not in CFC tasks. This result was confirmed with muscimol asymmetrical microinjections in DS and CeA, which reversibly inactivate these structures. On the other hand, similar pretest lesions as well as unilateral electrolytic lesions of CeA and DS in the same hemisphere did not affect TFC. Possible anatomical substrates underlying the observed effects are proposed. Overall, the present results underscore that other routes, aside from the well-established CeA projections to the periaqueductal gray, may contribute to the acquisition/consolidation of the freezing response associated to a TFC task. It is suggested that CeA may presumably influence DS processing via a synaptic relay on dopaminergic neurons of the substantia nigra compacta and retrorubral nucleus. The present observations are also in line with other studies showing that TFC and CFC responses are mediated by different anatomical networks. (C) 2008 IBRO. Published by Elsevier Ltd. All rights reserved.

Evidence for the thalamic targets of the medial hypothalamic defensive system mediating emotional memory to predatory threats

Previous studies from our laboratory have documented that the medial hypothalamic defensive system is critically involved in processing actual and contextual predatory threats, and that the dorsal premammillary nucleus (PMd) represents the hypothalamic site most responsive to predatory threats. Anatomical findings suggest that the PMd is in a position to modulate memory processing through a projecting branch to specific thalamic nuclei, i.e., the nucleus reuniens (RE) and the ventral part of the anteromedial nucleus (AMv). In the present study, we investigated the role of these thalamic targets in both unconditioned (i.e., fear responses to predatory threat) and conditioned (i.e., contextual responses to predator-related cues) defensive behaviors. During cat exposure, all experimental groups exhibited intense defensive responses with the animals spending most of the time in the home cage displaying freezing behavior. However, during exposure to the environment previously associated with a cat, the animals with combined RE + AMv lesions, and to a lesser degree, animals with single AMv unilateral lesions, but not animals with single RE lesions, presented a reduction of contextual conditioned defensive responses. Overall, the present results provide clear evidence suggesting that the PMd`s main thalamic targets (i.e., the nucleus reuniens and the AMv) seem to be critically involved in the emotional memory processing related to predator cues. (C) 2010 Elsevier Inc. All rights reserved.

Skovgaard`s adjustment to likelihood ratio tests in exponential family nonlinear models

Likelihood ratio tests can be substantially size distorted in small- and moderate-sized samples. In this paper, we apply Skovgaard`s [Skovgaard, I.M., 2001. Likelihood asymptotics. Scandinavian journal of Statistics 28, 3-321] adjusted likelihood ratio statistic to exponential family nonlinear models. We show that the adjustment term has a simple compact form that can be easily implemented from standard statistical software. The adjusted statistic is approximately distributed as X(2) with high degree of accuracy. It is applicable in wide generality since it allows both the parameter of interest and the nuisance parameter to be vector-valued. Unlike the modified profile likelihood ratio statistic obtained from Cox and Reid [Cox, D.R., Reid, N., 1987. Parameter orthogonality and approximate conditional inference. journal of the Royal Statistical Society B49, 1-39], the adjusted statistic proposed here does not require an orthogonal parameterization. Numerical comparison of likelihood-based tests of varying dispersion favors the test we propose and a Bartlett-corrected version of the modified profile likelihood ratio test recently obtained by Cysneiros and Ferrari [Cysneiros, A.H.M.A., Ferrari, S.L.P., 2006. An improved likelihood ratio test for varying dispersion in exponential family nonlinear models. Statistics and Probability Letters 76 (3), 255-265]. (C) 2008 Elsevier B.V. All rights reserved.

"An on-going individual adjustment" : a qualitative study of midwives' experiences counselling pregnant women on physical activity in Sweden

Background: In Sweden, midwives play prominent supportive role in antenatal care by counselling and promoting healthy lifestyles. This study aimed to explore how Swedish midwives experience the counselling of pregnant women on physical activity, specifically focusing on facilitators and barriers during pregnancy. Also, addressing whether the midwives perceive that their own lifestyle and body shape may influence the content of the counselling they provide. Methods: Eight focus group discussions (FGD) were conducted with 41 midwives working in antenatal care clinics in different parts of Sweden between September 2013 and January 2014. Purposive sampling was applied to ensure a variation in age, work experience, and geographical location. The FGD were digitally recorded, transcribed verbatim, and analyzed using manifest and latent content analysis. Results: The main theme- "An on-going individual adjustment" was built on three categories: "Counselling as a challenge"; "Counselling as walking the thin ice" and "Counselling as an opportunity" reflecting the midwives on-going need to adjust their counselling depending on each woman's specific situation. Furthermore, counselling pregnant women on physical activity was experienced as complex and ambiguous, presenting challenges as well as opportunities. When midwives challenged barriers to physical activity, they risked being rejected by the pregnant women. Despite risking rejection, the midwives tried to promote increased physical activity based on their assessment of individual needs of the pregnant woman. Some participants felt that their own lifestyle and body shape might negatively influence the counselling; however, the majority of participants did not agree with this perspective. Conclusions: Counselling on physical activity during pregnancy may be a challenging task for midwives, characterized by on-going adjustments based on a pregnant woman's individual needs. Midwives strive to find individual solutions to encourage physical activity. However, to improve their counselling, midwives may benefit from further training, also organizational and financial barriers need to be addressed. Such efforts might result in improved opportunities to further support pregnant women's motivation for performance of physical activity.

Differences in the Effects of Social Context on Emotional Responding

This study compares the effects of social cues on emotional experiences of men and women. Literature suggests that emotional responses are influenced by the presence and expressiveness of other individuals (Hess, Banse, & Kappas, 1995; Jacobs, Manstead, & Fischer, 2001; Fridlund, 1991). We examined whether social cues influence the experience of emotions differently for men and women. Research on gender differences in self-construal (Cross & Madson, 1997) led us to expect that women’s own emotional reactions would be more sensitive to emotional cues from other individuals than men’s.

The macroeconomic effects of infrequent information with adjustment costs

We extend the macroeconomic literature on Sstype rules by introducing infrequent information in a kinked ad justment cost model. We first show that optimal individual decision rules are both state-and -time dependent. We then develop an aggregation framework to study the macroeconomic implications of such optimal individual decision rules. In our model, a vast number of agents act together, and more so when uncertainty is large.The average effect of an aggregate shock is inversely related to its size and to aggregate uncertainty. These results are in contrast with those obtained with full information ad justment cost models.

The influence of emotional contagion on products evaluation

Emotional Contagion is the mechanism that includes mimicking and the automatic synchronization of facial expressions, vocalizations, postures, and movements with another person and, consequently, convergence of emotions between the sender and receiver. Researches of this mechanism conducted usually in the fields of Psychology and Marketing tends to investigate face-to-face interactions. However, the question remains to what extent, if any, emotional contagion may occur with facial expressions in photos, since many purchase situations are brought on by catalogues or websites. This thesis has the goal to verify this gap and, in addition, verify whether emotional contagion is more common in females than in males as stated in previous studies. Emotions have been studied because it is intuitively apparent that emotions affect the dynamics of the interaction between a salesperson and customers (Verbeke, 1997); in other words, emotions may significantly affect consumer behavior. Therefore, this thesis also verified whether the facial expressions that transmit emotions could be associated to product evaluations. To investigate these questions, an experiment was done with 171 participants, which were exposed to either smiling (positive emotion) or neutral advertising. The differences between the individual advertisements were limited to the facial expressions of figures in the advertisements (either smiling or neutral/without smiling). One specialist and two students analyzed videotaped records of the participants’ responses, and found that participants who saw the positive stimulus mimicked the picture (smiling back) confirming the Emotional Contagion in Photos (the first hypothesis). The second hypothesis was to analyze if there is difference based in gender. The results demonstrated that there is not a significant difference between genders; female and male equally suffer Emotional Contagion. The third hypothesis was related to whether the positive emotions vs. neutral emotions acquired from the positive facial expression in the photo are associated to a positive evaluation of the product also displayed in the photo. Evidences show that the ad with a positive expression could change more positively the attitude, the sympathy, the reliability, and the intention of purpose of the participant compared to those who were exposed to the neutral condition. Therefore, the analysis concludes that the facial expressions displayed in photos produce emotional contagion and may interfere on the evaluation product. A discussion of the theoretical and practical implications and limitations for these findings are presented.

Decision making naturalized: the interweaving of the unconscious, the emotional and the rational in decisions taken in a contigent world

Dadas as limitações e inadequações presentes, tanto no arquétipo do tomador de decisão como um agente racional, adotado nas teorias econômicas e gerenciais, quanto no estereótipo de um ser transcendental, tão presente na vida prosaica, se faz necessário substituí-los por uma nova perspectiva: onde o tomador de decisão é um animal emocional, frágil diante do acaso, e fruto de um processo evolutivo.

A psicologia comunitária como agente de transformações sociais

Nas últimas décadas tem ocorrido, no que se refere à Psicologia, uma mudança de abordagem do modelo intrapsíquico para uma perspectiva social, relativa ao comportamento humano. Uma das propostas essenciais do novo movimento consiste em declarar que as desordens emocionais originam-se do mau funcionamento das fontes básicas de suporte social. Foi nesse clima que em 1965 surgiu a Psicologia Comunitária. Esta se caracteriza pela busca de novos paradigmas que estão baseados, principalmente, na concepção preventiva de ajustamento e saúde, e no modelo ecológico. Neste trabalho pretendeu-se oferecer também como modelo alternativo da Psicologia Comunitária a aprendizagem social. Deste ponto de vista, ou seja, da aprendizagem social, os comportamentos considerados "desajustados" são vistos não como manifestações de problemas intrapsíquicos, e sim, como comportamentos que as pessoas aprenderam a copiar do ambiente através de reforços ou por meio de modelos oferecidos pela sociedade. Tal posição embora implique em que o comportamento humano pode ser manipulado pelo controle dos estímulos ambientais, não exclui uma visão fenomenológica do homem. Estas duas abordagens, aparentemente antagônicas, foram aqui apresentadas como um possível elemento dinamizador da Psicologia Comunitária. Ao mesmo tempo em que se tentou demonstrar ser o comportamento humano de alguma maneira controlado, pôs-se em relevo a liberdade que tem o homem de fazer escolhas, podendo ainda esforçar-se para evitar reforços aversivos e contribuir para uma sociedade menos repressora. O objetivo deste estudo foi apresentar uma visão histórica, teórica e ideológica da Psicologia Comunitária e abrir novas perspectivas em termos de sua praxis e sobretudo de suas metas. Daí por que indagou-se a respeito das mudanças pretendidas pela Psicologia Comunitária e alertou-se para que elas tenham um sentido transideológico, visando sobretudo ao bem estar da comunidade.

O enfeite nosso de todo dia: significados atribuídos aos acessórios de moda por tweens

Tweens são consideradas as crianças, especialmente as do sexo feminino, incluídas em uma faixa etária que pode variar, dependendo do autor do estudo, de sete a quatorze anos e, portanto, estão em um estágio entre a infância e a adolescência. Mais importante, contudo, do que os aspectos cronológicos que alocam os tweens entre crianças e adolescentes, os consumidores dessa faixa etária apresentam peculiaridades comportamentais e de atitudes devido à fase de transição social e emocional em que se encontram. Por exemplo, eles apresentam uma preocupação intensa quanto ao modo como são vistos por aqueles com quem convivem e lançam mão de artifícios variados para se reconhecerem e se expressarem nas suas relações sociais encontrando no significado dos bens uma via útil para declarar sua identidade, manifestar suas emoções e ressignificarem o mundo a sua volta. Partícipes cada vez mais eloquentes e ativos das relações de consumo, este segmento é ainda descrito por alguns estudiosos como a geração mais rica e influente da história econômica. Amparado por teorias sobre a participação das crianças no universo do consumo e sobre a atribuição de significado aos bens, sobremodo para a expressão de identidade, o estudo aqui alvitrado apresenta, por meio de análise interpretativista, os significados que tweens com idade entre oito e doze anos atribuem a acessórios pessoais. O método de pesquisa, de inspiração etnográfica, se efetivou em quatro meses de pesquisa de campo com observação participante de dez tweens e com entrevistas com familiares e proprietários de loja de acessórios. Fontes secundárias de informações como revistas e redes sociais também serviram para lançar luz ao entendimento do problema de pesquisa. Os resultados convergem para o uso dos acessórios como instrumentos importantes de ajuste social, seja porque ajudam as participantes a se expressarem e a se posicionarem frente a quem convivem, seja por se prestarem a auxiliar as tweens no que diz respeito às expectativas sociais quanto à boa aparência. Em nível mais particular, os acessórios se prestam igualmente a práticas performáticas lúdicas e de competências e ainda são instrumentos bastante úteis à aproximação e reforço de laços afetivos. Para além da contribuição teórica no que tange ao aprofundamento dos estudos sobre o comportamento do consumidor infantil e, sobretudo, do significado como bojo do processo de decisão de compra, este trabalho pretende, ainda, oferecer subsídios para deliberações de naturezas mercadológica e social ao perscrutar um fenômeno tão subjetivo de um público importante para essas duas esferas.

Regulation and wage adjustment patterns : non parametric evidence from longitudinal data

This paper gives a first step toward a methodology to quantify the influences of regulation on short-run earnings dynamics. It also provides evidence on the patterns of wage adjustment adopted during the recent high inflationary experience in Brazil.The large variety of official wage indexation rules adopted in Brazil during the recent years combined with the availability of monthly surveys on labor markets makes the Brazilian case a good laboratory to test how regulation affects earnings dynamics. In particular, the combination of large sample sizes with the possibility of following the same worker through short periods of time allows to estimate the cross-sectional distribution of longitudinal statistics based on observed earnings (e.g., monthly and annual rates of change).The empirical strategy adopted here is to compare the distributions of longitudinal statistics extracted from actual earnings data with simulations generated from minimum adjustment requirements imposed by the Brazilian Wage Law. The analysis provides statistics on how binding were wage regulation schemes. The visual analysis of the distribution of wage adjustments proves useful to highlight stylized facts that may guide future empirical work.

Speed of adjustment of capital structure: empirical study

We analyze the impact of firm-specific characteristics as well as economic factors on the speed of adjustment to the target debt ratio. Using different methods, we document speeds of adjustment ranging from 14.4% to 37%. The results indicate that the speed of adjustment is affected by business-cycle variables: The interaction term related to term spread reveals, as expected, faster adjustment in booms than in recessions and a negative relationship between short term spread and adjustment speed. We also show that the speed of adjustment becomes stationary when the increasing fractions of zero-debt firms are considered.

Fiscal adjustment, conditionality and politics in IMF programs

A common feature in programs of the International Monetary Fund (IMF) is the use of conditionalities, macroeconomic and structural measures that a requesting country should adopt to obtain an assistance package. The objective of this work is to conduct an empirical analysis of the economic and political determinants of such conditionalities. In particular, our main contribution consists in the development of a new measure of conditionality, fiscal adjustment, and its comparison with the most used in the literature, the number of conditions. We choose fiscal adjustment because it is an adequate proxy for program austerity, since its implementation carries economic and political costs. In the empirical exercise, we use data from 184 programs in the period of 1999 and 2012, and estimate how our two measures of conditionalities respond to the economic and political factors. Our results suggest that they are quite different. The main determinant of the number of conditions is the political proximity of the borrowing country to the Fund’s major shareholders, the members of G5. On the other hand, the main determinant of fiscal adjustment is the size of the government fiscal deficit. Finally, we did not find correlation between the size of fiscal adjustment and the number of conditions. These results suggest that the analysis of the content of IMF programs should take into account the different measures of agreed conditionality.

Asymetric price adjustment and loss aversion

Ajuste assimétrico de preço é observado em diversos mercados, notavelmente varejo de gasolina: um aumento de custo é passado para os consumidores mais rápido do que uma redução. Eu desenvolvo um modelo de busca dos consumidores que gera essa predição sob aversão à perda. Uma fração dos consumidores ignora os preços no mercado e pode adquirir informação a um custo, o que permite que as firmas tenham lucro com dispersão de preços. Ajuste assimétrico de preço emerge se os consumidores são aversos a perdas em relação a um preço de referência. Custos mais altos tornam os consumidores mais dispostos a procurar, mas também diminui as chances de encontrar preços baixos, gerando uma relação custo-preço convexa.