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An Auditory Steady-State Response (ASSR) is a valuable tool for determining auditory thresholds in individuals who are either unable or unwilling to cooperate with conventional behavioral testing methods. This study proposes a sequential test technique for automatic detection of ASSRs, incorporating a non-detection stopping criterion. The electrophysiological thresholds of a normal hearing volunteer were established using data collected from multichannel EEG signals. The detection probabilities and critical values were obtained via Monte Carlo simulations. Remarkably, application of the non-detection stopping criterion resulted in a 60% reduction in exam time in the absence of a response. These findings clearly demonstrate the significant potential of the sequential test in enhancing the performance of automatic audiometry.

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Quantitative abilities are well described in many species and in diverse life situations, including in the adult domestic cat. However, such abilities have been much less studied during ontogeny. In the present study we examined spontaneous quantity discrimination by pre-weaning age kittens in two-way food choice experiments. In Experiment 1, 26 kittens performed 12 trials with different ratios between the number of same-size food items. In Experiment 2, 24 other kittens performed eight trials with different ratios between the size of two food items. We found, in general, that the kittens discriminated between the different amounts of food and spontaneously chose the larger one, but that their choice was influenced by the ratio of difference. The kittens in Experiment 1 chose the larger number of same-size food items if the ratio was smaller than 0.4 and in Experiment 2 they chose the larger pieces of food if the ratio between the items was smaller than 0.5. Because the kittens' choice was not influenced by the absolute number of food items or the numerical difference between them in Experiment 1, it suggests that their cognitive performance relied on an analog magnitude system rather than on an object file system during the quantity discrimination tasks. We discuss our results considering the ecological and social background of cats and compare it with the performance of previously studied species.

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Mathai's pathway model is playing an increasingly prominent role in statistical distributions. As a generalization of a great variety of distributions, the pathway model allows the studying of several non-linear dynamics of complex systems. Here, we construct a model, called the Pareto-Mathai distribution, using the fact that the earthquakes' magnitudes of full catalogues are well-modeled by a Mathai distribution. The Pareto-Mathai distribution is used to study artificially induced microseisms in the mining industry. The fitting of a distribution for entire range of magnitudes allow us to calculate the completeness magnitude (Mc). Mathematical properties of the new distribution are studied. In addition, applying this model to data recorded at a Chilean mine, the magnitude Mc is estimated for several mine sectors and also the entire mine.

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Over the last decade, several methods for analysis of epileptiform signals in electroencephalography (EEG) have been proposed. These methods mainly use EEG signal features in either the time or the frequency domain to separate regular, interictal, and ictal brain activity. The aim of this work was to evaluate the feasibility of using functional connectivity (FC) based feature extraction methods for the analysis of epileptiform discharges in EEG signals. These signals were obtained from EEG-fMRI sessions of 10 patients with mesial temporal lobe epilepsy (MTLE) with unilateral hippocampal atrophy. The connectivity functions investigated were motif synchronization, imaginary coherence, and magnitude squared coherence in the alpha, beta, and gamma bands of the EEG. EEG signals were sectioned into 1-s epochs and classified according to (using neurologist markers): activity far from interictal epileptiform discharges (IED), activity immediately before an IED and, finally, mid-IED activity. Connectivity matrices for each epoch for each FC function were built, and graph theory was used to obtain the following metrics: strength, cluster coefficient, betweenness centrality, eigenvector centrality (both local and global), and global efficiency. The statistical distributions of these metrics were compared among the three classes, using ANOVA, for each FC function. We found significant differences in all global (p < 0.001) and local (p < 0.00002) graph metrics of the far class compared with before and mid for motif synchronization on the beta band; local betweenness centrality also pointed to a degree of lateralization on the frontotemporal structures. This analysis demonstrates the potential of FC measures, computed using motif synchronization, for the characterization of epileptiform activity of MTLE patients. This methodology may be helpful in the analysis of EEG-fMRI data applied to epileptic foci localization. Nonetheless, the methods must be tested with a larger sample and with other epileptic phenotypes.

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Auditory steady-state response (ASSR) is useful for hearing threshold estimation. The ASSR is usually detected with objective response detectors (ORD). The performance of these detectors depends on the signal-to-noise ratio (SNR) as well as the signal length. Since it is undesirable to increase the signal length, then, this work provides a multivariate technique for improving the SNR and consequently the detection power. We propose the insertion of a short calibration step before the detection protocol, in order to perform a search among the available electroencephalogram (EEG) derivations and select the derivation with the highest SNR. The ORD used in this work was the magnitude-squared coherence (MSC). The standard detection protocol is to use the same EEG derivation in all exams. Using 22-scalp positions, the new technique achieved a detection rate higher than that obtained in 99.13% of the standard detection protocol. When restrictions were applied to the search, a superior performance was achieved. Thus, the technique proposed was able to track the best EEG derivations before exams and seems to be able to deal with the variability between individuals and between sessions.

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Resumo O objetivo deste trabalho foi avaliar o efeito da manipulação das magnitudes das consequências individuais e culturais sobre o padrão de escolhas em situações de autocontrole ético e metacontingências. Seis estudantes universitários foram divididos em duas microculturas, uma com delineamento ABCAC'B'A e outra com um delineamento AC'B'ABCA. Nas condições B e B', a magnitude da consequência individual para respostas impulsivas aumentava enquanto a consequência cultural diminuía. Nas condições C e C', aumentava a magnitude da consequência cultural e diminuía a consequência individual. Os resultados indicaram a seleção de um padrão de escolhas em ambas as microculturas pela consequência cultural, com pouca ou nenhuma influência da manipulação da magnitude das consequências.

Abstract The objective of this study was to evaluate the effect of the magnitudes of the individual and cultural consequences on the pattern of choices in situations of ethical self-control and metacontingencies. Six college students were divided into two microcultures, one with ABCAC'B'A design and another with an AC'B'ABCA design. In conditions B and B' the magnitude of the individual consequence for impulsive responses increased while the cultural consequence diminished. In conditions C and C' the magnitude of the cultural consequence increased and the individual consequence diminished. The results indicated the selection of a pattern of choices by the groups of both microcultures, according to the cultural consequence, with little or no influence of the manipulation of the magnitude of the consequences.

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Introducción: La obesidad está asociada al uso frecuente de medicación de rescate y padecer asma de mayor gravedad. Los obesos asmáticos tienen menor reactividad bronquial, sin embargo, existe información limitada sobre la magnitud de la reversibilidad aguda al broncodilatador (RAB). Objetivo: Evaluar la magnitud de respuesta aguda al broncodilatador en pacientes asmáticos sobrepesos y obesos. Métodos: Se realizó un estudio descriptivo transversal con 49 pacientes asmáticos sobrepesos y obesos atendidos en consulta externa del Hospital Neumológico Benéfico Jurídico (enero 2017˗ enero 2018) y se constató mediante espirometría la respuesta aguda al broncodilatador. Resultados: Predominó la edad (40-59 años), mayor asociación de padecer asma, poca mejoría con la aplicación del broncodilatador. El sexo femenino (20-59 años) presentó mayor número que el masculino y menor reversibilidad al broncodilatador. Los pacientes con antecedentes patológicos familiares de asma o atopia representaron 73,5 por ciento del total. El 76,5 por ciento de los obesos no presentó mejoría con la aplicación del broncodilatador. Predominó la categoría de gravedad persistente moderada. Conclusiones: El sexo femenino tiene más riesgo de padecer asma y no tener mejoría al aplicar el broncodilatador. Los obesos mayores de 40 años tienen mayor riesgo de no presentar reversibilidad aguda al broncodilatador. Los antecedentes patológicos familiares de asma o atopia y personales de otras enfermedades no predisponen a menor reversibilidad aguda al broncodilatador. La gravedad del asma no influye en la reversibilidad aguda al broncodilatador(AU)

Introduction: Obesity is associated with the frequent use of rescue medication and suffering from more severe asthma. Obese asthmatics have less bronchial reactivity, however, there is limited information on the magnitude of acute bronchodilator reversibility. Objective: To assess the magnitude of the acute response to the bronchodilator in overweight and obese asthmatic patients. Methods: A cross-sectional descriptive study was carried out in 49 overweight and obese asthmatic patients seen in the outpatient clinic at Benéfico Jurídico Pneumologic Hospital from January 2017 to January 2018, and the acute response to bronchodilator was verified by spirometry. Results: Age predominated (40-59 years), greater association of suffering from asthma, and little improvement with the use of bronchodilator. The female sex (20-59 years) showed greater number than the male and less reversibility to bronchodilator. Patients with family pathological history of asthma or atopy represented 73.5 percent of the total. 76.5 percent of the obese did not show improvement with the use of bronchodilator. The category of moderate persistent severity predominated. Conclusions: The female sex has greater risk of suffering from asthma and has no improvement when applying bronchodilator. Obese individuals over 40 years of age have higher risk of not having acute reversibility to the bronchodilator. Family pathological history of asthma or atopy and personal history of other diseases do not predispose to less acute reversibility of bronchodilator. The severity of asthma does not influence acute reversibility to bronchodilator(AU)

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PURPOSE: To evaluate if the authors of published systematic reviews (SRs) reported the level of quality of evidence (QoE) in the top 5 impact factor infertility journals and to analyze if they used an appropriate wording to describe it. METHODS: This is a cross-sectional study. We searched in PubMed for SRs published in 2017 in the five infertility journals with the highest impact factor. We analyzed the proportion of SRs published in the top 5 impact factor infertility journals that reported the SRs' QoE, and the proportion of those SRs in which authors used consistent wording to describe QoE and magnitude of effect. RESULTS: The QoE was reported in only 21.4% of the 42 included SRs and in less than 10% of the abstracts. Although we did not find important differences in the report of QoE of those that showed statistically significant differences or not, p value was associated with the wording chosen by the authors. We found inconsistent reporting of the size the effect estimate in 54.8% (23/42) and in the level of QoE in 92.9% (39/42). Whereas the effect size was more consistently expressed in studies with statistically significant findings, QoE was better expressed in those cases in which the p value was over 0.05. CONCLUSION: We found that in 2017, less than 25% of the authors reported the overall QoE when publishing SRs. Authors focused more on statistical significance as a binary concept than on methodological limitations like study design, imprecision, indirectness, inconsistency, and publication bias. Authors should make efforts to report the QoE and interpret results accordingly.

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Objective response detection (ORD) techniques such as the magnitude-squared coherence (MSC) are mathematical methods tailored to detect potentials evoked by an external periodic stimulation. The performance of the MSC is directly proportional to the signal-to-noise ratio (SNR) of the recorded signal and the time spent for collecting data. An alternative to increasing the performance of detection techniques without increasing data recording time is to use the information from more than one signal simultaneously. In this context, this work proposes two new detection techniques based on the average and on the product of MSCs of two different signals. The critical values and detection probabilities were obtained theoretically and using a Monte Carlo simulation. The performances of the new detectors were evaluated using synthetic data and electroencephalogram (EEG) signals during photo and auditory stimulation. For the synthetic signals, the two proposed detectors exhibited a higher detection rate when compared to the rate of the traditional MSC technique. When applied to EEG signals, these detectors resulted in an increase of the mean detection rate in relation to MSC for visual and auditory stimulation of at least 25% and 13.21%, respectively. The proposed detectors may be considered as promising tools for clinical applications. Graphical Abstract.

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Abstracts Objective: The detection of the auditory steady-state responses is usually performed by an appropriate objective response detector applied to stimulus-related epochs of the raw electroencephalogram (EEG). In order to improve the detection time, sequential detection strategies are usually used. These multiple tests strategies increase the probability of mistakenly detecting a response. The aim of this study was to develop strategies to determine the critical values for the sequential detection strategies based on constant significance level tests. Design: Extensive Monte Carlo simulations were used to test these strategies for the magnitude-squared coherence (MSC) detector. The performances of these strategies were compared with previous works found in the literature. Study sample: All strategies were applied to synthetic and real EEG datasets. Results: The strategies ensure the desired significance level at the end of the sequential detection strategy. The simulated results are in accordance with the real data results. Conclusions: For the MSC detector, where the critical value depends on the number of epochs, the proposed sequential detection strategies obtain better performance regarding test time and detection rate, but worse overall detection rate compared to applying a test only once.

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BACKGROUND: Edge plays a special role in spatial perception and as well as in determining the brightness of a surface within borders. The aim of our study was to measure threshold brightness in different levels of edges thickness. METHODS: Steven's power law for circles modulating in luminance was estimated for 30 subjects (mean age 24 years, SD 3.3, 13 female). Stimuli were presented on the iMac display using the 11-bit graphic board and consisted of two circles of 3° of visual angle, separated by 10°. We tested 7 levels of Michelson contrast: 7, 8, 10, 15, 26, 50, and 100. Three edges filtering were tested (0.3, 0.8, and 1.5° of smoothing). The subjects' task was to judge the brightness of the edge filtered circle compared with the circle of the hard edge which was considered the modulus and received an arbitrary level of 50, representing the amount of brightness perception. In each trial, the same contrast level was presented in both circles. Five judgments were performed for each contrast level in edge filtering. RESULTS: We found an increase in the power law exponent as the increase of the edge filtering (for sigma of 0.3 = 0.43, sigma of 0.8 = 0.73, and sigma 1.5 = 0.97). All power function fitting had high correlation coefficients (r2 = .94, r2 = .95, r2 = .97, respectively to sigma 0.3, 0.8, and 1.5) passing to the model's adhesion criteria. CONCLUSIONS: There was a progressive distortion on the figure brightness perception as increasing the edge filtering suggesting the control of edges on the polarity of the overall brightness. Also, perceived brightness was increasingly veridical with increased filtering, approaching 1:1 correspondence at 1.5 sigmas.

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Abstract: Background: Edge plays a special role in spatial perception and as well as in determining the brightness of a surface within borders. The aim of our study was to measure threshold brightness in different levels of edges thickness. Methods: Steven's power law for circles modulating in luminance was estimated for 30 subjects (mean age 24 years, SD 3.3, 13 female). Stimuli were presented on the iMac display using the 11-bit graphic board and consisted of two circles of 3° of visual angle, separated by 10°. We tested 7 levels of Michelson contrast: 7, 8, 10, 15, 26, 50, and 100. Three edges filtering were tested (0.3, 0.8, and 1.5° of smoothing). The subjects' task was to judge the brightness of the edge filtered circle compared with the circle of the hard edge which was considered the modulus and received an arbitrary level of 50, representing the amount of brightness perception. In each trial, the same contrast level was presented in both circles. Five judgments were performed for each contrast level in edge filtering. Results: We found an increase in the power law exponent as the increase of the edge filtering (for sigma of 0.3 = 0.43, sigma of 0.8 = 0.73, and sigma 1.5 = 0.97). All power function fitting had high correlation coefficients (r2 = .94, r2 = .95, r2 = .97, respectively to sigma 0.3, 0.8, and 1.5) passing to the model's adhesion criteria. Conclusions: There was a progressive distortion on the figure brightness perception as increasing the edge filtering suggesting the control of edges on the polarity of the overall brightness. Also, perceived brightness was increasingly veridical with increased filtering, approaching 1:1 correspondence at 1.5 sigmas. (AU)

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Diversos estudos experimentais têm evidenciado a influência do estado afetivo, genericamente entendido, e emocional, em especificidade, no processamento cognitivo. Nesta sequência, tivemos como objetivo analisar o efeito da pré-exposição a estímulos de diferentes valências afetivas - negativa,positiva e neutra - na operação cognitiva de estimação de magnitude numérica da severidade de comportamentos antissociais. Participaram 37 estudantes universitários do mesmo grupo turma, do gênero feminino, entre os 18 e os 24 anos de idade, M = 19.53; DP = 1.06. Foram distribuídas aleatoriamente por três condições experimentais, definidas pela valência dos estímulos: negativa, positiva e neutra. Seguidamente, visualizaram um conjunto de 18 imagens - do IAPS - da valência da respetiva condição experimental, registrando na Self Assessment Manikin o estado afetivo que as imagens produziam. Após um intervalo de quatro minutos, as participantes estimaram a gravidade de 15 comportamentos antissociais. Os resultados indicaram que a pré-exposição de valência negativa teve um efeito significativo de diminuição da estimação da severidade dos comportamentos antissociais, comparativamente como os restantes grupos. Finalmente,procuramos na hipótese da dessensibilização emocional a compreensão dos resultados.

Several experimental studies have emphasized the influence of the affectivestate, generically understood, and emotional state, in specificity, in cognitive processing. In this sequence, we aimed to analyze the effect of pre-exposure to stimuli of different valences ­negative, positive and neutral­ in the cognitive operation of numerical magnitude estimation of antisocial behavior. 37 female university students took part in this study, all from the same class aged between 18 and 24 years, M = 19.53, SD = 1.06. They were randomly distributed in three experimental conditions related to the stimulus valence: negative, positive, and neutral. The participants viewed a series of 18 picturesof the International Affective Picture System of the respective experimental condition, registering into the Self Assessment Manikin the affective state that the images produced. After four minutes of interval, the participants estimated the severity of 15 antisocial behaviors. The results indicated that the negative valence pre- exposure had a significant effect of decreasing the estimation of the severity of antisocial behaviors, comparatively with the other groups. Finally, we discussed the results according to the hypothesis of emotional desensitization.

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Diversos estudos experimentais têm evidenciado a influência do estadoafetivo, genericamente entendido, e emocional, em especificidade, noprocessamento cognitivo. Nesta sequência, tivemos como objetivo analisar oefeito da pré-exposição a estímulos de diferentes valências afetivas - negativa,positiva e neutra - na operação cognitiva de estimação de magnitudenumérica da severidade de comportamentos antissociais. Participaram 37 estudantes universitários do mesmo grupo turma, do gênero feminino, entreos 18 e os 24 anos de idade, M = 19.53; DP = 1.06. Foram distribuídas aleatoriamente por três condições experimentais, definidas pela valência dos estímulos: negativa, positiva e neutra. Seguidamente, visualizaram um conjunto de 18 imagens - do IAPS - da valência da respetiva condição experimental, registrando na Self Assessment Manikin o estado afetivo que as imagens produziam. Após um intervalo de quatro minutos, as participantes estimaram a gravidade de 15 comportamentos antissociais. Os resultados indicaram que a pré-exposição de valência negativa teve um efeito significativo de diminuição da estimação da severidade dos comportamentos antissociais, comparativamente como os restantes grupos. Finalmente,procuramos na hipótese da dessensibilização emocional a compreensão dos resultados.

Several experimental studies have emphasized the influence of the affectivestate, generically understood, and emotional state, in specificity, in cognitive processing. In this sequence, we aimed to analyze the effect of pre-exposure to stimuli of different valences —negative, positive and neutral— in the cognitive operation of numerical magnitude estimation of antisocial behavior. 37 female university students took part in this study, all from the same class aged between 18 and 24 years, M = 19.53, SD = 1.06. They were randomly distributed in three experimental conditions related to the stimulus valence: negative, positive, and neutral. The participants viewed a series of 18 picturesof the International Affective Picture System of the respective experimental condition, registering into the Self Assessment Manikin the affective state that the images produced. After four minutes of interval, the participants estimated the severity of 15 antisocial behaviors. The results indicated that the negative valence pre- exposure had a significant effect of decreasing the estimation of the severity of antisocial behaviors, comparatively with the other groups. Finally, we discussed the results according to the hypothesis of emotional desensitization.

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Objective: To characterize the multifractal behavior of the beat to beat heart-period or RR fluctuations in fibromyalgia patients (FM) in comparison with healthy-matched subjects. Methods: Multifractral detrended fluctuation analysis (MDFA) was used to study multifractality in heartbeat times-series from 30 female healthy subjects and 30 female patients with fibromyalgia during day and night periods.The multifractal changes as derived from the magnitude and sign analysis of these RR fluctuations were also assessed. Results: The RR fluctuations dynamics of healthy subjects showed a broad multifractal spectrum. By contrast, a noticeable decrease in multifractality and non-linearity was observed for patients with fibromyalgia. In addition, the spectra corresponding to FM subjects were located on the average to the right of the spectra of healthy individuals, indicating that the local scaling exponents reflect a smoother behavior compared to healthy dynamics. Moreover, the multifractal analysis as applied to the magnitude and sign heartbeat series confirmed that, in addition to a decreased nonlinearity, fibromyalgia patients presented stronger anticorrelation in directionality, which did not remain invariant for small or rather larger fluctuations as it occurred in healthy subjects. Conclusion: When compared to healthy controls, fibromyalgia patients display decreased nonlinearity and stronger anticorrelations in heart period fluctuations. These findings reinforce the hypothesis of the potential role of the dysfunctional autonomic nervous system in the pathogenesis of fibromyalgia.

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Instrumental learning guides behavior toward resources. When such resources are no longer available, approach to previously reinforced locations is reduced, a process called extinction. The present experiments are concerned with factors affecting the extinction of acquired behaviors in toads. In previous experiments, total reward magnitude in acquisition and duration of extinction trials were confounded. The present experiments were designed to test the effects of these factors in factorial designs. Experiment 1 varied reward magnitude (900, 300, or 100 s of water access per trial) and amount of acquisition training (5 or 15 daily trials). With total amount of water access equated in acquisition, extinction with large rewards was faster (longer latencies in 900/5 than 300/15), but with total amount of training equated, extinction with small rewards was faster (longer latencies in 100/15 than 300/15). Experiment 2 varied reward magnitude (1200 or 120 s of water access per trial) while holding constant the number of acquisition trials (5 daily trials) and the duration of extinction trials (300 s). Extinction performance was lower with small, rather than large reward magnitude (longer latencies in 120/300 than in 1200/300). Thus, instrumental extinction depends upon the amount of time toads are exposed to the empty goal compartment during extinction trials.

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OBJECTIVE: To investigate the magnitude and determinants of the placebo response in studies with pediatric abdominal pain-related functional gastrointestinal disorders. STUDY DESIGN: The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and CINAHL were searched for systematic reviews and randomized placebo-controlled trials concerning children 4-18 years of age with an abdominal pain-related functional gastrointestinal disorder. The primary outcome was the pooled proportion of subjects assigned to placebo with improvement as defined by the authors. The effect of trial characteristics on the magnitude of the placebo response was investigated using univariate meta-regression analysis. RESULTS: Twenty-one trials were identified. The pooled proportion of subjects with improvement was 41% (95% CI, 34%-49%; 17 studies) and with no pain was 17% (95% CI, 8%-32%; 7 studies). The pooled standardized mean difference on the Faces Pain Scales compared with baseline was -0.73 (95% CI, -1.04 to -0.42; 8 studies). There was significant heterogeneity across studies with respect to both outcomes. Lower dosing frequency (P = .04), positive study (P = .03), longer duration of treatment (P < .001), and higher placebo dropout (P < .001) were associated with higher report of no pain. Response on Faces Pain Scales was greater in studies conducted in the Middle East (P = .002), in studies that did not report the randomization schedule (P = .02), and in studies with a higher percentage of females (P = .04). CONCLUSIONS: Approximately 41% of children with abdominal pain-related functional gastrointestinal disorders improve on placebo. Several trial characteristics are correlated significantly with the proportion of patients with no pain on placebo and with the magnitude of the placebo response on Faces Pain Scales. These data could be valuable for the design of future studies.

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El escrito ofrece un panorama general sobre el valor de la recompensa, respondiendo los interrogantes: ¿qué es?, ¿cómo se ha conceptualizado? y ¿qué investigaciones han utilizado el concepto? En sentido general, este se utiliza para calificar una recompensa como más o menos efectiva: mientras mayor sea el valor, mayor es su eficacia. Primero se describe la medición histórica del valor y cómo lo define la literatura sobre economía conductual. A continuación aparecen dos usos diferentes del concepto: (a) como constructo hipotético y (b) como variable interviniente. También se incluyen definiciones operacionales, en las que no se definen exhaustivamente las variables asociadas, entonces no se le considera variable interviniente, pero tampoco se agrega significado, más allá del nivel de observación, por lo que no son ejemplo de constructo hipotético. Posteriormente se explora la relación entre demora del reforzador y descuento temporal. Las consideraciones finales retoman la discusión sobre su valor heurístico en la investigación contemporánea.

The article offers a general panorama on the value of the reward, answering the questions: What is it? How has it been conceptualized? What investigations have used the concept? In general, a reward is rated as more or less effective: the greater the value, the greater its efficiency. First, the article discusses the historical measurement of value and how the literature on behavioral economics defines it. Next, two different uses of the concept are presented: (a) as a hypothetical construct and (b) as intervening variable. The text includes operational definitions where the associated variables are not defined exhaustively and therefore not considered as intervening variable, but which also add no meaning beyond the level of observation and therefore are not an example of a hypothetical construct. The article then explores the relationship between delay of the reinforcing agent and temporal discount. Finally, the article considers the discussion about the concept's heuristic value in contemporary research.

Este texto oferece um panorama geral sobre o valor da recompensa ao responder aos questionamentos: o que é, como vem sendo conceituado e quais pesquisas têm utilizado o conceito? Em sentido geral, este se utiliza para qualificar uma recompensa como mais ou menos efetiva: quanto maior for o valor, maior será sua eficácia. Primeiramente, descreve-se a medição histórica do valor e como a literatura sobre economia comportamental o define. A seguir, aparecem dois usos diferentes do conceito: (a) como construto hipotético e (b) como variável interventora. Também são incluídas definições operacionais, nas quais não se definem exaustivamente as variáveis associadas, portanto não é considerada variável interventora nem se agrega significado mais além do nível de observação, razão pela qual não são exemplos de construto hipotético. Posteriormente, explora-se a relação entre demora do reforçador e desconto temporal. As considerações finais retomam a discussão sobre seu valor heurístico na pesquisa contemporânea.

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INTRODUCTION: Congenital amusia is a developmental disorder associated with deficits in pitch height discrimination or in integrating pitch sequences into melodies. This quasi-experimental pilot study investigated whether there is an association between pitch and numerical processing deficits in congenital amusia. Since pitch height discrimination is considered a form of magnitude processing, we investigated whether individuals with amusia present an impairment in numerical magnitude processing, which would reflect damage to a generalized magnitude system. Alternatively, we investigated whether the numerical processing deficit would reflect a disconnection between nonsymbolic and symbolic number representations. METHOD: This study was conducted with 11 adult individuals with congenital amusia and a control comparison group of 6 typically developing individuals. Participants performed nonsymbolic and symbolic magnitude comparisons and number line tasks. Results were available from previous testing using the Montreal Battery of Evaluation of Amusia (MBEA) and a pitch change detection task (PCD). RESULTS: Compared to the controls, individuals with amusia exhibited no significant differences in their performance on both the number line and the nonsymbolic magnitude tasks. Nevertheless, they showed significantly worse performance on the symbolic magnitude task. Moreover, individuals with congenital amusia, who presented worse performance in the Meter subtest, also presented less precise nonsymbolic numerical representation. CONCLUSIONS: The relationship between meter and nonsymbolic numerical discrimination could indicate a general ratio processing deficit. The finding of preserved nonsymbolic numerical magnitude discrimination and mental number line representations, with impaired symbolic number processing, in individuals with congenital amusia indicates that (a) pitch height and numerical magnitude processing may not share common neural representations, and (b) in addition to pitch processing, individuals with amusia may present a deficit in accessing nonsymbolic numerical representations from symbolic representations. The symbolic access deficit could reflect a widespread impairment in the establishment of cortico-cortical connections between association areas.

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This article presents a tutorial about two protocols that can be used to measure an individual's perception of body image, direct and indirect , and which follow S.S. ( Stevens 1951) methods. Two psychophysical task approaches illustrate the ability of individuals to quantify body image distortions. We selected psychophysical tasks that indirectly assess a participant's behavioral component of body image (i.e., satisfaction tendencies about body image); and second, the cognitive component of body image (i.e., individuals' perceptual accuracy in magnitude estimation tasks, which depend on a familiarity with interval scales and the use of numbers and ratios to represent physical dimensions of stimuli). We determined individuals' perceptual sensitivity (i.e., his or her perceptual style ) to manipulations of the body's size by using Stevens' power function ( Stevens, 1951).

Este artigo apresenta um tutorial sobre dois protocolos que podem ser usados para medir a percepção de imagem corporal, direta e indiretamente , com base nos métodos de S.S. ( Stevens 1951). Duas abordagens psicofísicas ilustram a capacidade dos indivíduos para quantificar as distorções da imagem corporal. Nós selecionamos tarefas psicofísicas que avaliam indiretamente o componente comportamental da imagem corporal do participante (ou seja, tendências de satisfação sobre imagem corporal); e segundo, o componente cognitivo da imagem corporal (ou seja, precisão perceptual nas tarefas de estimativa de magnitude, que dependem de uma familiaridade com escalas de intervalo, e com o uso de números e proporções para representar dimensões físicas dos estímulos). Determinamos a sensibilidade perceptual dos indivíduos (ou seja, seu estilo perceptual) em tarefas de manipulação do tamanho do corpo, usando a função de potência de S.S. Stevens ( Stevens, 1951).

Este artículo presenta un tutorial en dos protocolos que pueden utilizarse para medir la percepción de imagen corporal, directa e indirectamente , con base en métodos de S.S. ( Stevens 1951). Dos enfoques físicos ilustran la capacidad de los individuos para cuantificar las distorsiones de la imagen corporal. Hemos seleccionado las tareas psico-físicas que evalúan indirectamente el componente conductual de la imagen corporal del participante (es decir, tendencias de satisfacción sobre imagen corporal); y en segundo lugar, el componente cognitivo de la imagen corporal (es decir, precisión perceptiva en las tareas de estimación de magnitud que dependen de una familiaridad con las escalas de intervalo, y con el uso de los números y proporciones para representar dimensiones físicas de los estímulos). Determinar la sensibilidad perceptual de los individuos (es decir, su estilo perceptual ) en tareas de manipulación del tamaño corporal, usando la función de potencia de S.S. Stevens ( Stevens, 1951).

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