Viés da Escalada, Daemons de Otimização, e a Influência da Narrativa Social Aceleracionista / Hill-Climbing Bias, Optimization Daemons, and the Influence of Accelerated Social Narratives

O fenômeno de aceleração social, intimamente ligado a nossa modernização tecnológica e os sistemas políticos e sociais que adotamos, vem sendo alvo de questionamentos por parte da teoria crítica por diversos filósofos e sociólogos, principalmente em relação a se tal "aceleração" seja algo que, possa ser justificável pelo bem comum da sociedade. De fato, as rápidas mudanças que ocorreram no último século causaram uma tremenda mudança em nossos estilos-de-vida, e na maneira como experienciamos o mundo. Que a nossa sociedade mudou e continua a mudar é um fato evidente quando olhamos criticamente para o passado e presente, e comparamos diferentes épocas da história humana. Neste ensaio tentaremos explorar algumas possíveis hipóteses que fundamentem o comportamento aceleracionista em certos fatores e mecanismo biológicos que caracterizam os sistemas de motivação e saciação humanos. Também tentaremos mostrar como certos fenômenos sociais podem auxiliar em fortalecer este tipo de comportamento, e suas possíveis origens evolutivas. Este estudo tem como objetivo principal fundamentar a Tese Aceleracionista em evidências neurofisiológicas, cognitivo-comportamentais, evolutivas e sociais.

The phenomenon of social acceleration is closely linked to our technological modernization and the political and social systems we have adopted, and it has been questioned by several philosophers and sociologists, especially in relation to whether such acceleration is something that can be justified for the common good of society. In fact, the rapid changes that have occurred in the last century have caused a tremendous change in our lifestyles, and in the way we experience the world. That society have changed and continues to change is an evident fact when we look critically to the past and our present and compare different times in human history. In this essay we will try to explore some possible hypotheses that underpin accelerated behavior, in certain biological factors and mechanisms that characterize human motivation and satiation systems. We will also try to show how certain social phenomena can help to strengthen this type of behavior, and its possible evolutionary origins. The main objective of this study is to base the Accelerationist Thesis on neurophysiological, cognitive-behavioral, evolutionary and also social evidence.

Are people who have a better smell sense, more affected from satiation? / As pessoas que têm melhor olfato são mais afetadas pela saciedade?

Abstract Introduction: The olfactory system is affected by the nutritional balance and chemical state of the body, serving as an internal sensor. All bodily functions are affected by energy loss, including olfaction; hunger can alter odour perception. Objective: In this study, we investigated the effect of fasting on olfactory perception in humans, and also assessed perceptual changes during satiation. Methods: The "Sniffin' Sticks" olfactory test was applied after 16 h of fasting, and again at least 1 h after Ramadan supper during periods of satiation. All participants were informed about the study procedure and provided informed consent. The study protocol was approved by the local Ethics Committee of Gaziosmanpaşa Taksim Education and Research Hospital (09/07/2014 no: 60). The study was conducted in accordance with the basic principles of the Declaration of Helsinki. Results: This prospective study included 48 subjects (20 males, 28 females) with a mean age of 33.6 ± 9.7 (range 20-72) years; their mean height was 169.1 ± 7.6 (range 150.0-185.0) cm, mean weight was 71.2 ± 17.6 (range 50.0-85.0) kg, and average BMI was 24.8 ± 5.3 (range 19.5-55.9). Scores were higher on all items pertaining to olfactory identification, thresholds and discrimination during fasting vs. satiation (p < 0.05). Identification (I) results: Identification scores were significantly higher during the fasting (median = 14.0) vs. satiation period (median = 13.0). Threshold (T) results: Threshold scores were significantly higher during the fasting (median = 7.3) vs. satiation period (median = 6.2). Discrimination (D) results: Discrimination scores were significantly higher during the fasting (median = 14.0) vs. satiation period (median = 13.0). The total TDI scores were 35.2 (fasting) vs. 32.6 (satiation). When we compared fasting threshold value of >9 and ≤9, the gap between the fasting and satiety thresholds was significantly greater in >9 (p < 0.05). Conclusion: Olfactory function improved during fasting and declined during satiation. The olfactory system is more sensitive, and more reactive to odours, under starvation conditions, and is characterised by reduced activity during satiation. This situation was more pronounced in patients with a better sense of smell. Olfaction-related neurotransmitters should be the target of further study.

Resumo Introdução: O sistema olfatório é afetado pelo equilíbrio nutricional e estado químico do corpo, que serve como um sensor interno. Todas as funções corporais são afetadas pela perda de energia, inclusive o olfato; a fome pode alterar a percepção do odor. Objetivo: Neste estudo, investigamos o efeito do jejum sobre a percepção olfativa em seres humanos, e também avaliamos as mudanças de percepção durante a saciedade. Método: O teste olfatório Sniffin Sticks foi aplicado após 16 horas de jejum e novamente pelo menos 1 hora após a ceia do Ramadã durante os períodos de saciedade. Todos os participantes foram informados sobre os procedimentos do estudo e forneceram o consentimento informado. O protocolo do estudo foi aprovado pelo Comitê de Ética do Gaziosmanpaşa Taksim Education e Research Hospital (2014/09/07 n° 60). O estudo foi conduzido de acordo com os princípios básicos da Declaração de Helsinki. Resultados: Foram incluídos 48 pacientes (20 homens, 28 mulheres) com média de 33,6 ± 9,7 aos (variação 20-72); a altura média deles era de 169,1 ± 7,6 cm (variação 150-185), o peso médio era de 71,2 ± 17,6 kg (variação de 50-85) e o IMC médio era de 24,8 ± 5,3 (variação de 19,5-55,9). Os escores foram maiores em todos os itens correspondentes à identificação olfativa, limiares e discriminação durante jejum vs. saciedade (p < 0,05). Resultados da identificação (I): os escores de identificação foram significativamente maiores durante o jejum (mediana = 14) vs. período de saciedade (mediana = 13). Resultados limiares (T): os escores limiares foram significativamente maiores durante o jejum (mediana = 7,3) vs. período de saciedade (mediana = 6,2). Resultados de discriminação (D): os escores de discriminação foram significativamente maiores durante o jejum (mediana = 14) vs. período de saciedade (mediana = 13). Os escores totais de TDI foram de 35,2 (jejum) vs. 32,6 (saciedade). Quando comparamos o valor do limiar de jejum de > 9 e ≤ 9, a diferença entre os limiares de jejum e de saciedade foi significativamente maior em > 9 (p < 0,05). Conclusão: A função olfatória melhorou durante o jejum e diminuiu durante a saciedade. O sistema olfatório é mais sensível e mais reativo aos odores em condições de fome e é caracterizado por atividade reduzida durante a saciedade. Essa situação foi mais pronunciada em pacientes com um melhor sentido olfativo. Os neurotransmissores relacionados com o olfato devem ser alvo de um estudo mais aprofundado.

Saciación vs saciedad: reguladores del consumo alimentario / Satiation and satiety in the regulation of energy intake

The study of the factors that regulate high energy food intake is especially relevant nowadays due to the high prevalence of overweight and obesity. Food intake regulation can be divided in two basic processes, namely satiation and satiety. Satiation is the process that determines the moment in which feeding stops and regulates the amount of ingested food during a single meal. Satiety is the interval between meals and regulates the time elapsed between two meals. The longer the interval, the lower energy intake. Each of these processes are regulated by different factors, which are here reviewed.

Distinct breakfast patterns on satiety perception in individuals with weight excess

ABSTRACT Objectives Western dietary pattern predisposes to weight gain, insulin resistance and cardiometabolic diseases. Promoting satiety via modifications in diet composition could be useful to fight weight gain. Mediterranean diet which is recognized to be cardioprotective contains high fiber and unsaturated fat contents. We compared the effects of distinct breakfast patterns on satiety of individuals at cardiometabolic risk, and examined the correlation of satiety level after each breakfast intervention period with glucose parameters. Materials and methods In this 10-week cross-over clinical trial, 54 individuals with weight excess were submitted to 2 types of 4-week isocaloric breakfasts (2-week washout), one typically Brazilian and a modified one, differing concerning fiber and types of fatty acids contents. Clinical data were collected before and after each breakfast. A satiety scale was applied at fasting and 10, 30 and 120’ after breakfast consumption. Repeated measures ANOVA, Student t test or non-parametric correspondents were used; correlations were tested by Pearson or Spearman coefficients. Results Anthropometric variations after breakfasts were not significant. Only after the modified breakfast, reduction in blood pressure levels was observed. The satiety level did not show significant variation across each period or between the breakfasts. Non-significant correlation between satiety and glucose, insulin and HOMA-IR values after each intervention period was observed. Conclusion We conclude that different breakfast compositions do not alter satiety level, which is not correlated to glucose parameters in overweight individuals. Stronger modifications of daily meals might be necessary to differentiate satiety levels under distinct dietary patterns.

Trastornos alimentarios del lactante y preescolar / Eating disorders in nursing and preschool children

Eating disorders among nursing and preschool children are a common cause of outpatient consultation in pediatrics and nutrition. It is essential to rule out organic causes, especially when there is nutritional involvement. Among non-organic causes there are several subtypes depending upon the trigger. Environmental and nutritional factors can be modified. Curiously, many of them are directly related to the perception of hunger and satiety the individual will develop from childhood.

Los trastornos de la alimentación en el lactante y preescolar siguen siendo un motivo frecuente de consulta en policlínicos de pediatría y nutrición infantil. Descartar causas orgánicas, sobre todo cuando existe compromiso nutricional, es de fundamental importancia. Dentro de los trastornos de origen no orgánico existen varios subtipos dependiendo de la causa desencadenante. Muchos factores involucrados tanto ambientales como nutri-cionales, son susceptibles de ser modificados. Curiosamente, muchos de ellos se relacionan directamente con la capacidad de percepción de las sensaciones de hambre y saciedad que el individuo desarrollará desde niño.

Serotonina e controle hipotalâmico da fome: uma revisão / Serotonin and hypothalamic control of hunger: a review

Este trabalho revisa a participação do sistema serotonérgico no controle da ingestão de alimentos e saciedade. É de grande interesse compreender a relevância desse sistema para o controle fisiológico do balanço energético e da obesidade. Mais de 35 anos de pesquisas sugerem que a serotonina (5-HT) desempenha um importante papel na saciedade. Assim, o sistema serotonérgico tem sido um alvo viável para o controle de peso. A 5-HT apresenta controle sobre a fome e a saciedade através de diversos receptores, com diferentes funções. O receptor 5-HT2C parece ser o mais importante na relação entre ingestão alimentar e balanço energético. Nesta revisão serão discutidos os mecanismos do sistema serotonérgico envolvidos no controle da ingestão de alimentos e saciedade.

This paper reviews involvement of the serotonergic system in the control of food intake and satiety. It is of great interest to understand the relevance of this system for physiological control of energy balance and obesity. Over 35 years of research suggest that serotonin (5-HT) plays an important role in satiety. Thus, the serotonergic system has been a viable target for weight control. The 5-HT has control over hunger and satiety through different receptors with distinct functions. The 5-HT2C receptor may be more important in the relationship between food intake and energy balance. This review will discuss the mechanisms of the serotonergic system involved in the control of food intake and satiety.

Matching salt intake to physiological need in rats using foraging protocols

Several studies of the quantitative relationship between sodium need and sodium intake in rats are reviewed. Using acute diuretic treatment 24 h beforehand, intake matches need fairly accurately when intake is spread out in time by using a hypotonic solution of NaCl. In contrast, using a hypertonic solution, intake is typically double the need. Using the same diuretic treatment, although the natriuresis occurs within ~1 h, the appetite appears only slowly over 24 h. Increased plasma levels of aldosterone parallel the increased intake; however, treatment with metyrapone blocks the rise in aldosterone but has no effect on appetite. Satiation of sodium appetite was studied in rats using sodium loss induced by chronic diuretic treatment and daily salt consumption sessions. When a simulated foraging cost was imposed on NaCl access in the form of a progressive ratio lever press task, rats showed satiation for NaCl (break point) after consuming an amount close to their estimated deficit. The chronic diuretic regimen produced hypovolemia and large increases in plasma aldosterone concentration and renin activity. These parameters were reversed to or toward non-depleted control values at the time of behavioral satiation in the progressive ratio protocol. Satiation mechanisms for sodium appetite thus do appear to exist. However, they do not operate quantitatively when concentrated salt is available at no effort, but instead allow overconsumption. There are reasons to believe that such a bias toward overconsumption may have been beneficial over evolutionary time, but such biasing for salt and other commodities is maladaptive in a resource-rich environment.

La ghrelina y su importancia con el eje gastrohipotalámico / Ghrelin and the gastro-hypothalamic axis

La obesidad se considera una de las enfermedades más importantes en la medida que acarrea gran morbilidad y mortalidad. El conocimiento de los mecanismos que intervienen en la saciedad, el peso corporal y el gasto de energía ha permitido el descubrimiento de hormonas relacionadas con el eje gastrohipotalámico, encargado de regular la saciedad y otros procesos que participan en la obesidad. La ghrelina, una hormona de secreción predominantemente gástrica, dio luz para comprender estos mecanismos, pues se trata de una hormona que regula la saciedad y el peso corporal por medio de mecanismos centrales mediados por el neuropéptido Y y la proteína relacionada con el agutí. En este artículo se revisan los aspectos fundamentales de esta hormona y de sus efectos en diversos órganos y sistemas.

Obesity is currently considered one of the most important diseases worldwide due to its high morbidity and mortality rates. The mechanisms involved in the control of satiation, body weight and energy expenditure has led to the discovery of new hormones that participate in the gastrichypothalamic axis in charge of regulating satiation and other obesity-related processes. Ghrelin a novel hormone secreted mainly by gastric tissue, has shed some light on this mechanism. It is a hormone that regulates satiation and body weight by centrally mediated mechanisms, involving neuropeptide Y and Agouti associated proteins. The present review focuses on some important physiological aspects of this hormone.

Determinantes dietéticos da ingestão alimentar e efeito na regulação do peso corporal / Dietetic determinants on food intake and effects in body weight regulation

Obesity is a multifactorial pathology currently considered one of the main public health problems. Its prevalence is increasing dramatically in the last decades, reaching huge rates in Brazil and many other countries. Regardless of the factors associated with genetic predisposition, this pathology is often associated with abnormal food intake, and also with high consumption of caloric foods and sedentary habits. Thus, obesity is the result of an imbalance between food intake and energy expenditure. One of the greatest research interests in nutrition has currently been the dietetic determinants that may exert an influence on the process of food intake, as well as the role of foods on physiological, physical and chemical factors most related to the processes of satiation and satiety. Based on these aspects, this paper analyzes several research works to gain a better insight of the dietetic factors affecting food intake and body weight regulation.

¿Es la obesidad el resultado de un epigenotipo equivocado? / Is obesity the consequence of an inadequate epigenotype?

Los individuos con obesidad asociada a sobrenutrición, manifiestan características genotípicas que modifican diversas funciones: Ingesta de alimentos condicionada por el ingreso calórico, composición de los macronutrientes, patabilidad, y control neuroendócrino del hambre y la saciedad; asimismo muestran una disminución en el egreso calórico producido por el metabolismo basal, el efecto térmico de los alimentos, el gasto calórico en ejercicio y la regulación de la termogénesis en situaciones de estrés. Existen además diferencias en la velocidad de oxidación de los nutrientes, tanto para cubrir las necesidades energéticas como para mantener la forma y la función. Es probable que muchos obesos, por seleción natural, presenten diferncias funcionales, algunas ocacionadas por mutaciones géneticas, que desde el punto de vista filogenético hayan facilitado la supervivencia de poblaciones nómadas y cazadoras con consumos alimentarios irregulares e inconstantes, pero que en la actualidad no sólo son innecesarias, sino que su asociación con sobrenutrición aumenta la morbimortalidad

Nuevas perspectivas acerca de la calidad nutricional de los hidratos de carbono complejos disponibles / New views on the nutritional quality of available complex carbohydrates

Los hidratos de carbono complejos han adquirido inportancia en la prevención de enfermedades crónicas no transmisibles. El presente artículo describe las características químicas y fisiológicas de los hidratos de carbono complejos y su interacción con otros alimentos. También se discute el efecto de los hidratos de carbono sobre la saciedad y la capacidad de aprendizaje

Electrophysiological correlates of diurnal feeding rhythm disruption in rats.

Electrical activity was recorded simultaneously from Ventromedial (VMH) and Lateral Hypothalamus (LH) in chronically prepared rats before and during one hour gustation tests as also during and after food intake in Group I (ad lib feeding) and Group II (3-hour food schedule) animals. The VMH/LH activity designated as Response Ratio (RR) was calculated and gave a better index of the food related behaviour. The basal RR was higher in Group I as compared to Group II rats but the response to glucose and saccharin ingestion showed a differential pattern of decrease after glucose intake in Group I and an increase in Group II. By contrast, on saccharin intake, Group I showed an increase. RRs after food intake did not show a significant change in both Group I and II rats.