Developing an Array Binary Code Assessment Rubric for Multiple- Choice Questions Using Item Arrays and Binary-Coded Responses

ERIC Educational Resources Information Center

Haro, Elizabeth K.; Haro, Luis S.

2014-01-01

The multiple-choice question (MCQ) is the foundation of knowledge assessment in K-12, higher education, and standardized entrance exams (including the GRE, MCAT, and DAT). However, standard MCQ exams are limited with respect to the types of questions that can be asked when there are only five choices. MCQs offering additional choices more…

Framing Effects: Dynamics and Task Domains

PubMed

Wang

1996-11-01

The author examines the mechanisms and dynamics of framing effects in risky choices across three distinct task domains (i.e., life-death, public property, and personal money). The choice outcomes of the problems presented in each of the three task domains had a binary structure of a sure thing vs a gamble of equal expected value; the outcomes differed in their framing conditions and the expected values, raging from 6000, 600, 60, to 6, numerically. It was hypothesized that subjects would become more risk seeking, if the sure outcome was below their aspiration level (the minimum requirement). As predicted, more subjects preferred the gamble when facing the life-death choice problems than facing the counterpart problems presented in the other two task domains. Subjects' risk preference varied categorically along the group size dimension in the life-death domain but changed more linearly over the expected value dimension in the monetary domain. Framing effects were observed in 7 of 13 pairs of problems, showing a positive frame-risk aversion and negative frame-risk seeking relationship. In addition, two types of framing effects were theoretically defined and empirically identified. A bidirectional framing effect involves a reversal in risk preference, and occurs when a decision maker's risk preference is ambiguous or weak. Four bidirectional effects were observed; in each case a majority of subjects preferred the sure outcome under a positive frame but the gamble under a negative frame. In contrast, a unidirectional framing effect refers to a preference shift due to the framing of choice outcomes: A majority of subjects preferred one choice outcome (either the sure thing or the gamble) under both framing conditions, with positive frame augmented the preference for the sure thing and negative frame augmented the preference for the gamble. These findings revealed some dynamic regularities of framing effects and posed implications for developing predictive and testable models of human decision making.

Correlates of decisional dynamics in the dorsal anterior cingulate cortex

PubMed Central

Hayden, Benjamin Y.

2017-01-01

We hypothesized that during binary economic choice, decision makers use the first option they attend as a default to which they compare the second. To test this idea, we recorded activity of neurons in the dorsal anterior cingulate cortex (dACC) of macaques choosing between gambles presented asynchronously. We find that ensemble encoding of the value of the first offer includes both choice-dependent and choice-independent aspects, as if reflecting a partial decision. That is, its responses are neither entirely pre- nor post-decisional. In contrast, coding of the value of the second offer is entirely decision dependent (i.e., post-decisional). This result holds even when offer-value encodings are compared within the same time period. Additionally, we see no evidence for 2 pools of neurons linked to the 2 offers; instead, all comparison appears to occur within a single functionally homogenous pool of task-selective neurons. These observations suggest that economic choices reflect a context-dependent evaluation of attended options. Moreover, they raise the possibility that value representations reflect, to some extent, a tentative commitment to a choice. PMID:29141002

The role of familiarity in binary choice inferences.

PubMed

Honda, Hidehito; Abe, Keiga; Matsuka, Toshihiko; Yamagishi, Kimihiko

2011-07-01

In research on the recognition heuristic (Goldstein & Gigerenzer, Psychological Review, 109, 75-90, 2002), knowledge of recognized objects has been categorized as "recognized" or "unrecognized" without regard to the degree of familiarity of the recognized object. In the present article, we propose a new inference model--familiarity-based inference. We hypothesize that when subjective knowledge levels (familiarity) of recognized objects differ, the degree of familiarity of recognized objects will influence inferences. Specifically, people are predicted to infer that the more familiar object in a pair of two objects has a higher criterion value on the to-be-judged dimension. In two experiments, using a binary choice task, we examined inferences about populations in a pair of two cities. Results support predictions of familiarity-based inference. Participants inferred that the more familiar city in a pair was more populous. Statistical modeling showed that individual differences in familiarity-based inference lie in the sensitivity to differences in familiarity. In addition, we found that familiarity-based inference can be generally regarded as an ecologically rational inference. Furthermore, when cue knowledge about the inference criterion was available, participants made inferences based on the cue knowledge about population instead of familiarity. Implications of the role of familiarity in psychological processes are discussed.

The attentional drift-diffusion model extends to simple purchasing decisions.

PubMed

Krajbich, Ian; Lu, Dingchao; Camerer, Colin; Rangel, Antonio

2012-01-01

How do we make simple purchasing decisions (e.g., whether or not to buy a product at a given price)? Previous work has shown that the attentional drift-diffusion model (aDDM) can provide accurate quantitative descriptions of the psychometric data for binary and trinary value-based choices, and of how the choice process is guided by visual attention. Here we extend the aDDM to the case of purchasing decisions, and test it using an eye-tracking experiment. We find that the model also provides a reasonably accurate quantitative description of the relationship between choice, reaction time, and visual fixations using parameters that are very similar to those that best fit the previous data. The only critical difference is that the choice biases induced by the fixations are about half as big in purchasing decisions as in binary choices. This suggests that a similar computational process is used to make binary choices, trinary choices, and simple purchasing decisions.

The Attentional Drift-Diffusion Model Extends to Simple Purchasing Decisions

PubMed Central

Krajbich, Ian; Lu, Dingchao; Camerer, Colin; Rangel, Antonio

2012-01-01

How do we make simple purchasing decisions (e.g., whether or not to buy a product at a given price)? Previous work has shown that the attentional drift-diffusion model (aDDM) can provide accurate quantitative descriptions of the psychometric data for binary and trinary value-based choices, and of how the choice process is guided by visual attention. Here we extend the aDDM to the case of purchasing decisions, and test it using an eye-tracking experiment. We find that the model also provides a reasonably accurate quantitative description of the relationship between choice, reaction time, and visual fixations using parameters that are very similar to those that best fit the previous data. The only critical difference is that the choice biases induced by the fixations are about half as big in purchasing decisions as in binary choices. This suggests that a similar computational process is used to make binary choices, trinary choices, and simple purchasing decisions. PMID:22707945

Mental Effort in Binary Categorization Aided by Binary Cues

ERIC Educational Resources Information Center

Botzer, Assaf; Meyer, Joachim; Parmet, Yisrael

2013-01-01

Binary cueing systems assist in many tasks, often alerting people about potential hazards (such as alarms and alerts). We investigate whether cues, besides possibly improving decision accuracy, also affect the effort users invest in tasks and whether the required effort in tasks affects the responses to cues. We developed a novel experimental tool…

An attentional drift diffusion model over binary-attribute choice.

PubMed

Fisher, Geoffrey

2017-11-01

In order to make good decisions, individuals need to identify and properly integrate information about various attributes associated with a choice. Since choices are often complex and made rapidly, they are typically affected by contextual variables that are thought to influence how much attention is paid to different attributes. I propose a modification of the attentional drift-diffusion model, the binary-attribute attentional drift diffusion model (baDDM), which describes the choice process over simple binary-attribute choices and how it is affected by fluctuations in visual attention. Using an eye-tracking experiment, I find the baDDM makes accurate quantitative predictions about several key variables including choices, reaction times, and how these variables are correlated with attention to two attributes in an accept-reject decision. Furthermore, I estimate an attribute-based fixation bias that suggests attention to an attribute increases its subjective weight by 5%, while the unattended attribute's weight is decreased by 10%. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of rule induction, decision trees and formal concept analysis approaches for classification

NASA Astrophysics Data System (ADS)

Kotelnikov, E. V.; Milov, V. R.

2018-05-01

Rule-based learning algorithms have higher transparency and easiness to interpret in comparison with neural networks and deep learning algorithms. These properties make it possible to effectively use such algorithms to solve descriptive tasks of data mining. The choice of an algorithm depends also on its ability to solve predictive tasks. The article compares the quality of the solution of the problems with binary and multiclass classification based on the experiments with six datasets from the UCI Machine Learning Repository. The authors investigate three algorithms: Ripper (rule induction), C4.5 (decision trees), In-Close (formal concept analysis). The results of the experiments show that In-Close demonstrates the best quality of classification in comparison with Ripper and C4.5, however the latter two generate more compact rule sets.

Choice of threshold line angle for binary phase-only filters

NASA Astrophysics Data System (ADS)

Vijaya Kumar, Bhagavatula; Hendrix, Charles D.

1993-10-01

The choice of threshold line angle (TLA) is an important issue in designing Binary Phase-Only Filters (BPOFs). In this paper, we derive expressions that explicitly relate the TLA to correlation peak intensity. We also show some examples that illustrate the effect of choosing the wrong TLA.

A Conditional Curie-Weiss Model for Stylized Multi-group Binary Choice with Social Interaction

NASA Astrophysics Data System (ADS)

Opoku, Alex Akwasi; Edusei, Kwame Owusu; Ansah, Richard Kwame

2018-04-01

This paper proposes a conditional Curie-Weiss model as a model for decision making in a stylized society made up of binary decision makers that face a particular dichotomous choice between two options. Following Brock and Durlauf (Discrete choice with social interaction I: theory, 1955), we set-up both socio-economic and statistical mechanical models for the choice problem. We point out when both the socio-economic and statistical mechanical models give rise to the same self-consistent equilibrium mean choice level(s). Phase diagram of the associated statistical mechanical model and its socio-economic implications are discussed.

Comparing observer models and feature selection methods for a task-based statistical assessment of digital breast tomsynthesis in reconstruction space

NASA Astrophysics Data System (ADS)

Park, Subok; Zhang, George Z.; Zeng, Rongping; Myers, Kyle J.

2014-03-01

A task-based assessment of image quality1 for digital breast tomosynthesis (DBT) can be done in either the projected or reconstructed data space. As the choice of observer models and feature selection methods can vary depending on the type of task and data statistics, we previously investigated the performance of two channelized- Hotelling observer models in conjunction with 2D Laguerre-Gauss (LG) and two implementations of partial least squares (PLS) channels along with that of the Hotelling observer in binary detection tasks involving DBT projections.2, 3 The difference in these observers lies in how the spatial correlation in DBT angular projections is incorporated in the observer's strategy to perform the given task. In the current work, we extend our method to the reconstructed data space of DBT. We investigate how various model observers including the aforementioned compare for performing the binary detection of a spherical signal embedded in structured breast phantoms with the use of DBT slices reconstructed via filtered back projection. We explore how well the model observers incorporate the spatial correlation between different numbers of reconstructed DBT slices while varying the number of projections. For this, relatively small and large scan angles (24° and 96°) are used for comparison. Our results indicate that 1) given a particular scan angle, the number of projections needed to achieve the best performance for each observer is similar across all observer/channel combinations, i.e., Np = 25 for scan angle 96° and Np = 13 for scan angle 24°, and 2) given these sufficient numbers of projections, the number of slices for each observer to achieve the best performance differs depending on the channel/observer types, which is more pronounced in the narrow scan angle case.

Goal-Directed Decision Making with Spiking Neurons.

PubMed

Friedrich, Johannes; Lengyel, Máté

2016-02-03

Behavioral and neuroscientific data on reward-based decision making point to a fundamental distinction between habitual and goal-directed action selection. The formation of habits, which requires simple updating of cached values, has been studied in great detail, and the reward prediction error theory of dopamine function has enjoyed prominent success in accounting for its neural bases. In contrast, the neural circuit mechanisms of goal-directed decision making, requiring extended iterative computations to estimate values online, are still unknown. Here we present a spiking neural network that provably solves the difficult online value estimation problem underlying goal-directed decision making in a near-optimal way and reproduces behavioral as well as neurophysiological experimental data on tasks ranging from simple binary choice to sequential decision making. Our model uses local plasticity rules to learn the synaptic weights of a simple neural network to achieve optimal performance and solves one-step decision-making tasks, commonly considered in neuroeconomics, as well as more challenging sequential decision-making tasks within 1 s. These decision times, and their parametric dependence on task parameters, as well as the final choice probabilities match behavioral data, whereas the evolution of neural activities in the network closely mimics neural responses recorded in frontal cortices during the execution of such tasks. Our theory provides a principled framework to understand the neural underpinning of goal-directed decision making and makes novel predictions for sequential decision-making tasks with multiple rewards. Goal-directed actions requiring prospective planning pervade decision making, but their circuit-level mechanisms remain elusive. We show how a model circuit of biologically realistic spiking neurons can solve this computationally challenging problem in a novel way. The synaptic weights of our network can be learned using local plasticity rules such that its dynamics devise a near-optimal plan of action. By systematically comparing our model results to experimental data, we show that it reproduces behavioral decision times and choice probabilities as well as neural responses in a rich set of tasks. Our results thus offer the first biologically realistic account for complex goal-directed decision making at a computational, algorithmic, and implementational level. Copyright © 2016 the authors 0270-6474/16/361529-18$15.00/0.

Goal-Directed Decision Making with Spiking Neurons

PubMed Central

Lengyel, Máté

2016-01-01

Behavioral and neuroscientific data on reward-based decision making point to a fundamental distinction between habitual and goal-directed action selection. The formation of habits, which requires simple updating of cached values, has been studied in great detail, and the reward prediction error theory of dopamine function has enjoyed prominent success in accounting for its neural bases. In contrast, the neural circuit mechanisms of goal-directed decision making, requiring extended iterative computations to estimate values online, are still unknown. Here we present a spiking neural network that provably solves the difficult online value estimation problem underlying goal-directed decision making in a near-optimal way and reproduces behavioral as well as neurophysiological experimental data on tasks ranging from simple binary choice to sequential decision making. Our model uses local plasticity rules to learn the synaptic weights of a simple neural network to achieve optimal performance and solves one-step decision-making tasks, commonly considered in neuroeconomics, as well as more challenging sequential decision-making tasks within 1 s. These decision times, and their parametric dependence on task parameters, as well as the final choice probabilities match behavioral data, whereas the evolution of neural activities in the network closely mimics neural responses recorded in frontal cortices during the execution of such tasks. Our theory provides a principled framework to understand the neural underpinning of goal-directed decision making and makes novel predictions for sequential decision-making tasks with multiple rewards. SIGNIFICANCE STATEMENT Goal-directed actions requiring prospective planning pervade decision making, but their circuit-level mechanisms remain elusive. We show how a model circuit of biologically realistic spiking neurons can solve this computationally challenging problem in a novel way. The synaptic weights of our network can be learned using local plasticity rules such that its dynamics devise a near-optimal plan of action. By systematically comparing our model results to experimental data, we show that it reproduces behavioral decision times and choice probabilities as well as neural responses in a rich set of tasks. Our results thus offer the first biologically realistic account for complex goal-directed decision making at a computational, algorithmic, and implementational level. PMID:26843636

QTest: Quantitative Testing of Theories of Binary Choice.

PubMed

Regenwetter, Michel; Davis-Stober, Clintin P; Lim, Shiau Hong; Guo, Ying; Popova, Anna; Zwilling, Chris; Cha, Yun-Shil; Messner, William

2014-01-01

The goal of this paper is to make modeling and quantitative testing accessible to behavioral decision researchers interested in substantive questions. We provide a novel, rigorous, yet very general, quantitative diagnostic framework for testing theories of binary choice. This permits the nontechnical scholar to proceed far beyond traditionally rather superficial methods of analysis, and it permits the quantitatively savvy scholar to triage theoretical proposals before investing effort into complex and specialized quantitative analyses. Our theoretical framework links static algebraic decision theory with observed variability in behavioral binary choice data. The paper is supplemented with a custom-designed public-domain statistical analysis package, the QTest software. We illustrate our approach with a quantitative analysis using published laboratory data, including tests of novel versions of "Random Cumulative Prospect Theory." A major asset of the approach is the potential to distinguish decision makers who have a fixed preference and commit errors in observed choices from decision makers who waver in their preferences.

A Neural Mechanism of Preference Shifting Under Zero Price Condition

PubMed Central

Votinov, Mikhail; Aso, Toshihiko; Fukuyama, Hidenao; Mima, Tatsuya

2016-01-01

In everyday life, free products have a strong appeal to us, even if we do not need them. Behavioral studies demonstrated that people have a tendency to switch their preference from preferred more expensive products to less preferable, cheaper alternatives, when the cheaper option becomes free. However, the neural representation of this behavioral anomaly called “Zero price” is still unclear. Using fMRI, we studied subjects while they performed binary preference choice task for items with different prices. We found that zero-related change of preference was associated with activation of the choice network, which includes inferior parietal lobule (IPL), posterior cingulate cortex and medial prefrontal cortex. Moreover, the amount of activation in medial prefrontal cortex was positively correlated with the subjective happiness score of getting free products. Our findings suggest that the Zero-price effect is driven by affective evaluations during decision-making. PMID:27148024

Parabolic discounting of monetary rewards by physical effort.

PubMed

Hartmann, Matthias N; Hager, Oliver M; Tobler, Philippe N; Kaiser, Stefan

2013-11-01

When humans and other animals make decisions in their natural environments prospective rewards have to be weighed against costs. It is well established that increasing costs lead to devaluation or discounting of reward. While our knowledge about discount functions for time and probability costs is quite advanced, little is known about how physical effort discounts reward. In the present study we compared three different models in a binary choice task in which human participants had to squeeze a handgrip to earn monetary rewards: a linear, a hyperbolic, and a parabolic model. On the group as well as the individual level, the concave parabolic model explained most variance of the choice data, thus contrasting with the typical hyperbolic discounting of reward value by delay. Research on effort discounting is not only important to basic science but also holds the potential to quantify aberrant motivational states in neuropsychiatric disorders. Copyright © 2013 Elsevier B.V. All rights reserved.

Age Differences in Memory Retrieval Shift: Governed by Feeling-of-Knowing?

PubMed Central

Hertzog, Christopher; Touron, Dayna R.

2010-01-01

The noun-pair lookup (NP) task was used to evaluate strategic shift from visual scanning to retrieval. We investigated whether age differences in feeling-of-knowing (FOK) account for older adults' delayed retrieval shift. Participants were randomly assigned to one of three conditions: (1) standard NP learning, (2) fast binary FOK judgments, or (3) Choice, where participants had to choose in advance whether to see the look-up table or respond from memory. We found small age differences in FOK magnitudes, but major age differences in memory retrieval choices that mirrored retrieval use in the standard NP task. Older adults showed lower resolution in their confidence judgments (CJs) for recognition memory tests on the NP items, and this difference appeared to influence rates of retrieval shift, given that retrieval use was correlated with CJ magnitudes in both age groups. Older adults had particular difficulty with accuracy and confidence for rearranged pairs, relative to intact pairs. Older adults' slowed retrieval shift appears to be due to (a) impaired associative learning early in practice, not just a lower FOK; but also (b) retrieval reluctance later in practice after the degree of associative learning would afford memory-based responding. PMID:21401263

Rational and Boundedly Rational Behavior in a Binary Choice Sender-Receiver Game

ERIC Educational Resources Information Center

Landi, Massimiliano; Colucci, Domenico

2008-01-01

The authors investigate the strategic rationale behind the message sent by Osama bin Laden on the eve of the 2004 U.S. Presidential elections. They model this situation as a signaling game in which a population of receivers takes a binary choice, the outcome is decided by majority rule, sender and receivers have conflicting interests, and there is…

The memory state heuristic: A formal model based on repeated recognition judgments.

PubMed

Castela, Marta; Erdfelder, Edgar

2017-02-01

The recognition heuristic (RH) theory predicts that, in comparative judgment tasks, if one object is recognized and the other is not, the recognized one is chosen. The memory-state heuristic (MSH) extends the RH by assuming that choices are not affected by recognition judgments per se, but by the memory states underlying these judgments (i.e., recognition certainty, uncertainty, or rejection certainty). Specifically, the larger the discrepancy between memory states, the larger the probability of choosing the object in the higher state. The typical RH paradigm does not allow estimation of the underlying memory states because it is unknown whether the objects were previously experienced or not. Therefore, we extended the paradigm by repeating the recognition task twice. In line with high threshold models of recognition, we assumed that inconsistent recognition judgments result from uncertainty whereas consistent judgments most likely result from memory certainty. In Experiment 1, we fitted 2 nested multinomial models to the data: an MSH model that formalizes the relation between memory states and binary choices explicitly and an approximate model that ignores the (unlikely) possibility of consistent guesses. Both models provided converging results. As predicted, reliance on recognition increased with the discrepancy in the underlying memory states. In Experiment 2, we replicated these results and found support for choice consistency predictions of the MSH. Additionally, recognition and choice latencies were in agreement with the MSH in both experiments. Finally, we validated critical parameters of our MSH model through a cross-validation method and a third experiment. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Acquisition of linguistic procedures for printed words: neuropsychological implications for learning.

PubMed

Berninger, V W

1988-10-01

A microcomputerized experiment, administered to 45 children in the 2nd, 5th, and 8th month of first grade, manipulated three variables: (a) stimulus unit (whole word or letter-by-letter presentation), (b) nature of stimulus information (phonically regular words, phonically irregular words, nonsense words, and letter strings, which differ in whether phonemic, orthographic, semantic, and/or name codes are available), and (c) linguistic task (lexical decision, naming, and written reproduction). Letter-by-letter presentation resulted in more accurate lexical decision and naming but not more accurate written reproduction. Interactions between nature of stimulus information and linguistic task occurred. Throughout the year, accuracy was greater for lexical decision than for naming or written reproduction. The superiority of lexical decision cannot be attributed to the higher probability of correct responses on a binary choice task because only consistently correct responses on repeated trials were analyzed. The earlier development of lexical decision, a receptive task, than of naming or written reproduction, production tasks, suggests that hidden units (Hinton & Sejnowski, 1986) in tertiary cortical areas may abstract visual-linguistic associations in printed words before production units in primary cortical areas can produce printed words orally or graphically.

Exchanging the liquidity hypothesis: Delay discounting of money and self-relevant non-money rewards

PubMed Central

Stuppy-Sullivan, Allison M.; Tormohlen, Kayla N.; Yi, Richard

2015-01-01

Evidence that primary rewards (e.g., food and drugs of abuse) are discounted more than money is frequently attributed to money's high degree of liquidity, or exchangeability for many commodities. The present study provides some evidence against this liquidity hypothesis by contrasting delay discounting of monetary rewards (liquid) and non-monetary commodities (non-liquid) that are self-relevant and utility-matched. Ninety-seven (97) undergraduate students initially completed a conventional binary-choice delay discounting of money task. Participants returned one week later and completed a self-relevant commodity delay discounting task. Both conventional hypothesis testing and more-conservative tests of statistical equivalence revealed correspondence in rate of delay discounting of money and self-relevant commodities, and in one magnitude condition, less discounting for the latter. The present results indicate that liquidity of money cannot fully account for the lower rate of delay discounting compared to non-money rewards. PMID:26556504

Can Simple Transmission Chains Foster Collective Intelligence in Binary-Choice Tasks?

PubMed

Moussaïd, Mehdi; Seyed Yahosseini, Kyanoush

2016-01-01

In many social systems, groups of individuals can find remarkably efficient solutions to complex cognitive problems, sometimes even outperforming a single expert. The success of the group, however, crucially depends on how the judgments of the group members are aggregated to produce the collective answer. A large variety of such aggregation methods have been described in the literature, such as averaging the independent judgments, relying on the majority or setting up a group discussion. In the present work, we introduce a novel approach for aggregating judgments-the transmission chain-which has not yet been consistently evaluated in the context of collective intelligence. In a transmission chain, all group members have access to a unique collective solution and can improve it sequentially. Over repeated improvements, the collective solution that emerges reflects the judgments of every group members. We address the question of whether such a transmission chain can foster collective intelligence for binary-choice problems. In a series of numerical simulations, we explore the impact of various factors on the performance of the transmission chain, such as the group size, the model parameters, and the structure of the population. The performance of this method is compared to those of the majority rule and the confidence-weighted majority. Finally, we rely on two existing datasets of individuals performing a series of binary decisions to evaluate the expected performances of the three methods empirically. We find that the parameter space where the transmission chain has the best performance rarely appears in real datasets. We conclude that the transmission chain is best suited for other types of problems, such as those that have cumulative properties.

Can Simple Transmission Chains Foster Collective Intelligence in Binary-Choice Tasks?

PubMed Central

Moussaïd, Mehdi; Seyed Yahosseini, Kyanoush

2016-01-01

In many social systems, groups of individuals can find remarkably efficient solutions to complex cognitive problems, sometimes even outperforming a single expert. The success of the group, however, crucially depends on how the judgments of the group members are aggregated to produce the collective answer. A large variety of such aggregation methods have been described in the literature, such as averaging the independent judgments, relying on the majority or setting up a group discussion. In the present work, we introduce a novel approach for aggregating judgments—the transmission chain—which has not yet been consistently evaluated in the context of collective intelligence. In a transmission chain, all group members have access to a unique collective solution and can improve it sequentially. Over repeated improvements, the collective solution that emerges reflects the judgments of every group members. We address the question of whether such a transmission chain can foster collective intelligence for binary-choice problems. In a series of numerical simulations, we explore the impact of various factors on the performance of the transmission chain, such as the group size, the model parameters, and the structure of the population. The performance of this method is compared to those of the majority rule and the confidence-weighted majority. Finally, we rely on two existing datasets of individuals performing a series of binary decisions to evaluate the expected performances of the three methods empirically. We find that the parameter space where the transmission chain has the best performance rarely appears in real datasets. We conclude that the transmission chain is best suited for other types of problems, such as those that have cumulative properties. PMID:27880825

QTest: Quantitative Testing of Theories of Binary Choice

PubMed Central

Regenwetter, Michel; Davis-Stober, Clintin P.; Lim, Shiau Hong; Guo, Ying; Popova, Anna; Zwilling, Chris; Cha, Yun-Shil; Messner, William

2014-01-01

The goal of this paper is to make modeling and quantitative testing accessible to behavioral decision researchers interested in substantive questions. We provide a novel, rigorous, yet very general, quantitative diagnostic framework for testing theories of binary choice. This permits the nontechnical scholar to proceed far beyond traditionally rather superficial methods of analysis, and it permits the quantitatively savvy scholar to triage theoretical proposals before investing effort into complex and specialized quantitative analyses. Our theoretical framework links static algebraic decision theory with observed variability in behavioral binary choice data. The paper is supplemented with a custom-designed public-domain statistical analysis package, the QTest software. We illustrate our approach with a quantitative analysis using published laboratory data, including tests of novel versions of “Random Cumulative Prospect Theory.” A major asset of the approach is the potential to distinguish decision makers who have a fixed preference and commit errors in observed choices from decision makers who waver in their preferences. PMID:24999495

Heterogeneous Suppression of Sequential Effects in Random Sequence Generation, but Not in Operant Learning.

PubMed

Shteingart, Hanan; Loewenstein, Yonatan

2016-01-01

There is a long history of experiments in which participants are instructed to generate a long sequence of binary random numbers. The scope of this line of research has shifted over the years from identifying the basic psychological principles and/or the heuristics that lead to deviations from randomness, to one of predicting future choices. In this paper, we used generalized linear regression and the framework of Reinforcement Learning in order to address both points. In particular, we used logistic regression analysis in order to characterize the temporal sequence of participants' choices. Surprisingly, a population analysis indicated that the contribution of the most recent trial has only a weak effect on behavior, compared to more preceding trials, a result that seems irreconcilable with standard sequential effects that decay monotonously with the delay. However, when considering each participant separately, we found that the magnitudes of the sequential effect are a monotonous decreasing function of the delay, yet these individual sequential effects are largely averaged out in a population analysis because of heterogeneity. The substantial behavioral heterogeneity in this task is further demonstrated quantitatively by considering the predictive power of the model. We show that a heterogeneous model of sequential dependencies captures the structure available in random sequence generation. Finally, we show that the results of the logistic regression analysis can be interpreted in the framework of reinforcement learning, allowing us to compare the sequential effects in the random sequence generation task to those in an operant learning task. We show that in contrast to the random sequence generation task, sequential effects in operant learning are far more homogenous across the population. These results suggest that in the random sequence generation task, different participants adopt different cognitive strategies to suppress sequential dependencies when generating the "random" sequences.

Modeling Search Behaviors during the Acquisition of Expertise in a Sequential Decision-Making Task.

PubMed

Moënne-Loccoz, Cristóbal; Vergara, Rodrigo C; López, Vladimir; Mery, Domingo; Cosmelli, Diego

2017-01-01

Our daily interaction with the world is plagued of situations in which we develop expertise through self-motivated repetition of the same task. In many of these interactions, and especially when dealing with computer and machine interfaces, we must deal with sequences of decisions and actions. For instance, when drawing cash from an ATM machine, choices are presented in a step-by-step fashion and a specific sequence of choices must be performed in order to produce the expected outcome. But, as we become experts in the use of such interfaces, is it possible to identify specific search and learning strategies? And if so, can we use this information to predict future actions? In addition to better understanding the cognitive processes underlying sequential decision making, this could allow building adaptive interfaces that can facilitate interaction at different moments of the learning curve. Here we tackle the question of modeling sequential decision-making behavior in a simple human-computer interface that instantiates a 4-level binary decision tree (BDT) task. We record behavioral data from voluntary participants while they attempt to solve the task. Using a Hidden Markov Model-based approach that capitalizes on the hierarchical structure of behavior, we then model their performance during the interaction. Our results show that partitioning the problem space into a small set of hierarchically related stereotyped strategies can potentially capture a host of individual decision making policies. This allows us to follow how participants learn and develop expertise in the use of the interface. Moreover, using a Mixture of Experts based on these stereotyped strategies, the model is able to predict the behavior of participants that master the task.

An auditory oddball brain-computer interface for binary choices.

PubMed

Halder, S; Rea, M; Andreoni, R; Nijboer, F; Hammer, E M; Kleih, S C; Birbaumer, N; Kübler, A

2010-04-01

Brain-computer interfaces (BCIs) provide non-muscular communication for individuals diagnosed with late-stage motoneuron disease (e.g., amyotrophic lateral sclerosis (ALS)). In the final stages of the disease, a BCI cannot rely on the visual modality. This study examined a method to achieve high accuracies using auditory stimuli only. We propose an auditory BCI based on a three-stimulus paradigm. This paradigm is similar to the standard oddball but includes an additional target (i.e. two target stimuli, one frequent stimulus). Three versions of the task were evaluated in which the target stimuli differed in loudness, pitch or direction. Twenty healthy participants achieved an average information transfer rate (ITR) of up to 2.46 bits/min and accuracies of 78.5%. Most subjects (14 of 20) achieved their best performance with targets differing in pitch. With this study, the viability of the paradigm was shown for healthy participants and will next be evaluated with individuals diagnosed with ALS or locked-in syndrome (LIS) after stroke. The here presented BCI offers communication with binary choices (yes/no) independent of vision. As it requires only little time per selection, it may constitute a reliable means of communication for patients who lost all motor function and have a short attention span. 2009 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Not all choices are created equal: Task-relevant choices enhance motor learning compared to task-irrelevant choices.

PubMed

Carter, Michael J; Ste-Marie, Diane M

2017-12-01

Lewthwaite et al. (2015) reported that the learning benefits of exercising choice (i.e., their self-controlled condition) are not restricted to task-relevant features (e.g., feedback). They found that choosing one's golf ball color (Exp. 1) or choosing which of two tasks to perform at a later time plus which of two artworks to hang (Exp. 2) resulted in better retention than did being denied these same choices (i.e., yoked condition). The researchers concluded that the learning benefits derived from choice, whether irrelevant or relevant to the to-be-learned task, are predominantly motivational because choice is intrinsically rewarding and satisfies basic psychological needs. However, the absence of a group that made task-relevant choices and the lack of psychological measures significantly weakened their conclusions. Here, we investigated how task-relevant and task-irrelevant choices affect motor-skill learning. Participants practiced a spatiotemporal motor task in either a task-relevant group (choice over feedback schedule), a task-irrelevant group (choice over the color of an arm-wrap plus game selection), or a no-choice group. The results showed significantly greater learning in the task-relevant group than in both the task-irrelevant and no-choice groups, who did not differ significantly. Critically, these learning differences were not attributed to differences in perceptions of competence or autonomy, but instead to superior error-estimation abilities. These results challenge the perspective that motivational influences are the root cause of self-controlled learning advantages. Instead, the findings add to the growing evidence highlighting that the informational value gained from task-relevant choices makes a greater relative contribution to these advantages than motivational influences do.

Value-based attentional capture influences context-dependent decision-making

PubMed Central

Cha, Kexin; Rangsipat, Napat; Serences, John T.

2015-01-01

Normative theories posit that value-based decision-making is context independent. However, decisions between two high-value options can be suboptimally biased by the introduction of a third low-value option. This context-dependent modulation is consistent with the divisive normalization of the value of each stimulus by the total value of all stimuli. In addition, an independent line of research demonstrates that pairing a stimulus with a high-value outcome can lead to attentional capture that can mediate the efficiency of visual information processing. Here we tested the hypothesis that value-based attentional capture interacts with value-based normalization to influence the optimality of decision-making. We used a binary-choice paradigm in which observers selected between two targets and the color of each target indicated the magnitude of their reward potential. Observers also had to simultaneously ignore a task-irrelevant distractor rendered in a color that was previously associated with a specific reward magnitude. When the color of the task-irrelevant distractor was previously associated with a high reward, observers responded more slowly and less optimally. Moreover, as the learned value of the distractor increased, electrophysiological data revealed an attenuation of the lateralized N1 and N2Pc responses evoked by the relevant choice stimuli and an attenuation of the late positive deflection (LPD). Collectively, these behavioral and electrophysiological data suggest that value-based attentional capture and value-based normalization jointly mediate the influence of context on free-choice decision-making. PMID:25995350

Value-based attentional capture influences context-dependent decision-making.

PubMed

Itthipuripat, Sirawaj; Cha, Kexin; Rangsipat, Napat; Serences, John T

2015-07-01

Normative theories posit that value-based decision-making is context independent. However, decisions between two high-value options can be suboptimally biased by the introduction of a third low-value option. This context-dependent modulation is consistent with the divisive normalization of the value of each stimulus by the total value of all stimuli. In addition, an independent line of research demonstrates that pairing a stimulus with a high-value outcome can lead to attentional capture that can mediate the efficiency of visual information processing. Here we tested the hypothesis that value-based attentional capture interacts with value-based normalization to influence the optimality of decision-making. We used a binary-choice paradigm in which observers selected between two targets and the color of each target indicated the magnitude of their reward potential. Observers also had to simultaneously ignore a task-irrelevant distractor rendered in a color that was previously associated with a specific reward magnitude. When the color of the task-irrelevant distractor was previously associated with a high reward, observers responded more slowly and less optimally. Moreover, as the learned value of the distractor increased, electrophysiological data revealed an attenuation of the lateralized N1 and N2Pc responses evoked by the relevant choice stimuli and an attenuation of the late positive deflection (LPD). Collectively, these behavioral and electrophysiological data suggest that value-based attentional capture and value-based normalization jointly mediate the influence of context on free-choice decision-making. Copyright © 2015 the American Physiological Society.

Condition interference in rats performing a choice task with switched variable- and fixed-reward conditions.

PubMed

Funamizu, Akihiro; Ito, Makoto; Doya, Kenji; Kanzaki, Ryohei; Takahashi, Hirokazu

2015-01-01

Because humans and animals encounter various situations, the ability to adaptively decide upon responses to any situation is essential. To date, however, decision processes and the underlying neural substrates have been investigated under specific conditions; thus, little is known about how various conditions influence one another in these processes. In this study, we designed a binary choice task with variable- and fixed-reward conditions and investigated neural activities of the prelimbic cortex and dorsomedial striatum in rats. Variable- and fixed-reward conditions induced flexible and inflexible behaviors, respectively; one of the two conditions was randomly assigned in each trial for testing the possibility of condition interference. Rats were successfully conditioned such that they could find the better reward holes of variable-reward-condition and fixed-reward-condition trials. A learning interference model, which updated expected rewards (i.e., values) used in variable-reward-condition trials on the basis of combined experiences of both conditions, better fit choice behaviors than conventional models which updated values in each condition independently. Thus, although rats distinguished the trial condition, they updated values in a condition-interference manner. Our electrophysiological study suggests that this interfering value-updating is mediated by the prelimbic cortex and dorsomedial striatum. First, some prelimbic cortical and striatal neurons represented the action-reward associations irrespective of trial conditions. Second, the striatal neurons kept tracking the values of variable-reward condition even in fixed-reward-condition trials, such that values were possibly interferingly updated even in the fixed-reward condition.

Estimating the executive demands of a one-back choice reaction time task by means of the selective interference paradigm.

PubMed

Szmalec, Arnaud; Vandierendonck, André

2007-08-01

The present study proposes a new executive task, the one-back choice reaction time (RT) task, and implements the selective interference paradigm to estimate the executive demands of the processing components involved in this task. Based on the similarities between a one-back choice RT task and the n-back updating task, it was hypothesized that one-back delaying of a choice reaction involves executive control. In three experiments, framed within Baddeley's (1986) working-memory model, a one-back choice RT task, a choice RT task, articulatory suppression, and matrix tapping were performed concurrently with primary tasks involving verbal, visuospatial, and executive processing. The results demonstrate that one-back delaying of a choice reaction interferes with tasks requiring executive control, while the potential interference at the level of the verbal or visuospatial working memory slave systems remains minimal.

Multi-task feature selection in microarray data by binary integer programming.

PubMed

Lan, Liang; Vucetic, Slobodan

2013-12-20

A major challenge in microarray classification is that the number of features is typically orders of magnitude larger than the number of examples. In this paper, we propose a novel feature filter algorithm to select the feature subset with maximal discriminative power and minimal redundancy by solving a quadratic objective function with binary integer constraints. To improve the computational efficiency, the binary integer constraints are relaxed and a low-rank approximation to the quadratic term is applied. The proposed feature selection algorithm was extended to solve multi-task microarray classification problems. We compared the single-task version of the proposed feature selection algorithm with 9 existing feature selection methods on 4 benchmark microarray data sets. The empirical results show that the proposed method achieved the most accurate predictions overall. We also evaluated the multi-task version of the proposed algorithm on 8 multi-task microarray datasets. The multi-task feature selection algorithm resulted in significantly higher accuracy than when using the single-task feature selection methods.

An empirical comparison of methods for analyzing correlated data from a discrete choice survey to elicit patient preference for colorectal cancer screening

PubMed Central

2012-01-01

Background A discrete choice experiment (DCE) is a preference survey which asks participants to make a choice among product portfolios comparing the key product characteristics by performing several choice tasks. Analyzing DCE data needs to account for within-participant correlation because choices from the same participant are likely to be similar. In this study, we empirically compared some commonly-used statistical methods for analyzing DCE data while accounting for within-participant correlation based on a survey of patient preference for colorectal cancer (CRC) screening tests conducted in Hamilton, Ontario, Canada in 2002. Methods A two-stage DCE design was used to investigate the impact of six attributes on participants' preferences for CRC screening test and willingness to undertake the test. We compared six models for clustered binary outcomes (logistic and probit regressions using cluster-robust standard error (SE), random-effects and generalized estimating equation approaches) and three models for clustered nominal outcomes (multinomial logistic and probit regressions with cluster-robust SE and random-effects multinomial logistic model). We also fitted a bivariate probit model with cluster-robust SE treating the choices from two stages as two correlated binary outcomes. The rank of relative importance between attributes and the estimates of β coefficient within attributes were used to assess the model robustness. Results In total 468 participants with each completing 10 choices were analyzed. Similar results were reported for the rank of relative importance and β coefficients across models for stage-one data on evaluating participants' preferences for the test. The six attributes ranked from high to low as follows: cost, specificity, process, sensitivity, preparation and pain. However, the results differed across models for stage-two data on evaluating participants' willingness to undertake the tests. Little within-patient correlation (ICC ≈ 0) was found in stage-one data, but substantial within-patient correlation existed (ICC = 0.659) in stage-two data. Conclusions When small clustering effect presented in DCE data, results remained robust across statistical models. However, results varied when larger clustering effect presented. Therefore, it is important to assess the robustness of the estimates via sensitivity analysis using different models for analyzing clustered data from DCE studies. PMID:22348526

Lesions of dorsal striatum eliminate lose-switch responding but not mixed-response strategies in rats.

PubMed

Skelin, Ivan; Hakstol, Rhys; VanOyen, Jenn; Mudiayi, Dominic; Molina, Leonardo A; Holec, Victoria; Hong, Nancy S; Euston, David R; McDonald, Robert J; Gruber, Aaron J

2014-05-01

We used focal brain lesions in rats to examine how dorsomedial (DMS) and dorsolateral (DLS) regions of the striatum differently contribute to response adaptation driven by the delivery or omission of rewards. Rats performed a binary choice task under two modes: one in which responses were rewarded on half of the trials regardless of choice; and another 'competitive' one in which only unpredictable choices were rewarded. In both modes, control animals were more likely to use a predictable lose-switch strategy than animals with lesions of either DMS or DLS. Animals with lesions of DMS presumably relied more on DLS for behavioural control, and generated repetitive responses in the first mode. These animals then shifted to a random response strategy in the competitive mode, thereby performing better than controls or animals with DLS lesions. Analysis using computational models of reinforcement learning indicated that animals with striatal lesions, particularly of the DLS, had blunted reward sensitivity and less stochasticity in the choice mechanism. These results provide further evidence that the rodent DLS is involved in rapid response adaptation that is more sophisticated than that embodied by the classic notion of habit formation driven by gradual stimulus-response learning. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Linear models to perform treaty verification tasks for enhanced information security

DOE PAGES

MacGahan, Christopher J.; Kupinski, Matthew A.; Brubaker, Erik M.; ...

2016-11-12

Linear mathematical models were applied to binary-discrimination tasks relevant to arms control verification measurements in which a host party wishes to convince a monitoring party that an item is or is not treaty accountable. These models process data in list-mode format and can compensate for the presence of variability in the source, such as uncertain object orientation and location. The Hotelling observer applies an optimal set of weights to binned detector data, yielding a test statistic that is thresholded to make a decision. The channelized Hotelling observer applies a channelizing matrix to the vectorized data, resulting in a lower dimensionalmore » vector available to the monitor to make decisions. We demonstrate how incorporating additional terms in this channelizing-matrix optimization offers benefits for treaty verification. We present two methods to increase shared information and trust between the host and monitor. The first method penalizes individual channel performance in order to maximize the information available to the monitor while maintaining optimal performance. Second, we present a method that penalizes predefined sensitive information while maintaining the capability to discriminate between binary choices. Data used in this study was generated using Monte Carlo simulations for fission neutrons, accomplished with the GEANT4 toolkit. Custom models for plutonium inspection objects were measured in simulation by a radiation imaging system. Model performance was evaluated and presented using the area under the receiver operating characteristic curve.« less

Linear models to perform treaty verification tasks for enhanced information security

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacGahan, Christopher J.; Kupinski, Matthew A.; Brubaker, Erik M.

Linear mathematical models were applied to binary-discrimination tasks relevant to arms control verification measurements in which a host party wishes to convince a monitoring party that an item is or is not treaty accountable. These models process data in list-mode format and can compensate for the presence of variability in the source, such as uncertain object orientation and location. The Hotelling observer applies an optimal set of weights to binned detector data, yielding a test statistic that is thresholded to make a decision. The channelized Hotelling observer applies a channelizing matrix to the vectorized data, resulting in a lower dimensionalmore » vector available to the monitor to make decisions. We demonstrate how incorporating additional terms in this channelizing-matrix optimization offers benefits for treaty verification. We present two methods to increase shared information and trust between the host and monitor. The first method penalizes individual channel performance in order to maximize the information available to the monitor while maintaining optimal performance. Second, we present a method that penalizes predefined sensitive information while maintaining the capability to discriminate between binary choices. Data used in this study was generated using Monte Carlo simulations for fission neutrons, accomplished with the GEANT4 toolkit. Custom models for plutonium inspection objects were measured in simulation by a radiation imaging system. Model performance was evaluated and presented using the area under the receiver operating characteristic curve.« less

Linear models to perform treaty verification tasks for enhanced information security

NASA Astrophysics Data System (ADS)

MacGahan, Christopher J.; Kupinski, Matthew A.; Brubaker, Erik M.; Hilton, Nathan R.; Marleau, Peter A.

2017-02-01

Linear mathematical models were applied to binary-discrimination tasks relevant to arms control verification measurements in which a host party wishes to convince a monitoring party that an item is or is not treaty accountable. These models process data in list-mode format and can compensate for the presence of variability in the source, such as uncertain object orientation and location. The Hotelling observer applies an optimal set of weights to binned detector data, yielding a test statistic that is thresholded to make a decision. The channelized Hotelling observer applies a channelizing matrix to the vectorized data, resulting in a lower dimensional vector available to the monitor to make decisions. We demonstrate how incorporating additional terms in this channelizing-matrix optimization offers benefits for treaty verification. We present two methods to increase shared information and trust between the host and monitor. The first method penalizes individual channel performance in order to maximize the information available to the monitor while maintaining optimal performance. Second, we present a method that penalizes predefined sensitive information while maintaining the capability to discriminate between binary choices. Data used in this study was generated using Monte Carlo simulations for fission neutrons, accomplished with the GEANT4 toolkit. Custom models for plutonium inspection objects were measured in simulation by a radiation imaging system. Model performance was evaluated and presented using the area under the receiver operating characteristic curve.

Biased predecisional processing of leading and nonleading alternatives.

PubMed

Blanchard, Simon J; Carlson, Kurt A; Meloy, Margaret G

2014-03-01

When people obtain information about choice alternatives in a set one attribute at a time, they rapidly identify a leading alternative. Although previous research has established that people then distort incoming information, it is unclear whether distortion occurs through favoring of the leading alternative, disfavoring of the trailing alternative, or both. Prior examinations have not explored the predecisional treatment of the nonleading alternative (or alternatives) because they conceptualized distortion as a singular construct in binary choice and measured it using a relative item comparing the evaluation of both alternatives simultaneously. In this article, we introduce a measure of distortion at the level of the alternative, which allows for measuring whether predecisional distortion favors or disfavors every alternative being considered in choice sets of various sizes. We report that both proleader and antitrailer distortion occur and that the use of antitrailer processing differs between binary choices and multiple-options choices.

Exchanging the liquidity hypothesis: Delay discounting of money and self-relevant non-money rewards.

PubMed

Stuppy-Sullivan, Allison M; Tormohlen, Kayla N; Yi, Richard

2016-01-01

Evidence that primary rewards (e.g., food and drugs of abuse) are discounted more than money is frequently attributed to money's high degree of liquidity, or exchangeability for many commodities. The present study provides some evidence against this liquidity hypothesis by contrasting delay discounting of monetary rewards (liquid) and non-monetary commodities (non-liquid) that are self-relevant and utility-matched. Ninety-seven (97) undergraduate students initially completed a conventional binary-choice delay discounting of money task. Participants returned one week later and completed a self-relevant commodity delay discounting task. Both conventional hypothesis testing and more-conservative tests of statistical equivalence revealed correspondence in rate of delay discounting of money and self-relevant commodities, and in one magnitude condition, less discounting for the latter. The present results indicate that liquidity of money cannot fully account for the lower rate of delay discounting compared to non-money rewards. Copyright © 2015 Elsevier B.V. All rights reserved.

Does sensitivity in binary choice tasks depend on response modality?

PubMed

Szumska, Izabela; van der Lubbe, Rob H J; Grzeczkowski, Lukasz; Herzog, Michael H

2016-07-01

In most models of vision, a stimulus is processed in a series of dedicated visual areas, leading to categorization of this stimulus, and possible decision, which subsequently may be mapped onto a motor-response. In these models, stimulus processing is thought to be independent of the response modality. However, in theories of event coding, common coding, and sensorimotor contingency, stimuli may be very specifically mapped onto certain motor-responses. Here, we compared performance in a shape localization task and used three different response modalities: manual, saccadic, and verbal. Meta-contrast masking was employed at various inter-stimulus intervals (ISI) to manipulate target visibility. Although we found major differences in reaction times for the three response modalities, accuracy remained at the same level for each response modality (and all ISIs). Our results support the view that stimulus-response (S-R) associations exist only for specific instances, such as reflexes or skills, but not for arbitrary S-R pairings. Copyright © 2016 Elsevier Inc. All rights reserved.

A Novel Design of 4-Class BCI Using Two Binary Classifiers and Parallel Mental Tasks

PubMed Central

Geng, Tao; Gan, John Q.; Dyson, Matthew; Tsui, Chun SL; Sepulveda, Francisco

2008-01-01

A novel 4-class single-trial brain computer interface (BCI) based on two (rather than four or more) binary linear discriminant analysis (LDA) classifiers is proposed, which is called a “parallel BCI.” Unlike other BCIs where mental tasks are executed and classified in a serial way one after another, the parallel BCI uses properly designed parallel mental tasks that are executed on both sides of the subject body simultaneously, which is the main novelty of the BCI paradigm used in our experiments. Each of the two binary classifiers only classifies the mental tasks executed on one side of the subject body, and the results of the two binary classifiers are combined to give the result of the 4-class BCI. Data was recorded in experiments with both real movement and motor imagery in 3 able-bodied subjects. Artifacts were not detected or removed. Offline analysis has shown that, in some subjects, the parallel BCI can generate a higher accuracy than a conventional 4-class BCI, although both of them have used the same feature selection and classification algorithms. PMID:18584040

Individual differences in decision making by foraging hummingbirds.

PubMed

Morgan, Kate V; Hurly, T Andrew; Healy, Susan D

2014-11-01

For both humans and animals preference for one option over others can be influenced by the context in which the options occur. In animals, changes in preference could be due to comparative decision-making or to changes in the energy state of the animal when making decisions. We investigated which of these possibilities better explained the response of wild hummingbirds to the addition of a decoy option to a set of two options by presenting Rufous hummingbirds (Selasphorus rufus) with a foraging experiment with two treatments. In each treatment the birds were presented with a binary choice between two options and a trinary choice with three options. In treatment one the binary choice was between a volume option and a concentration option, whereas in treatment two the same volume option was presented alongside an alternative concentration option. In the trinary choice, birds were presented with the same options as in the binary choice plus one of two inferior options. Birds changed their preferences when a poorer option was added to the choice set: birds increased their preference for the same option when in the presence of either decoy. Which option differed across individuals and the changes in preference were not readily explained by either energy maximisation or the decoy effect. The consistency in response within individuals, however, would suggest that the individual itself brings an extra dimension to context-dependent decision-making. This article is part of a Special Issue entitled: Cognition in the wild. Copyright © 2014 Elsevier B.V. All rights reserved.

Walking delays anticipatory postural adjustments but not reaction times in a choice reaction task.

PubMed

Haridas, C; Gordon, I T; Misiaszek, J E

2005-06-01

During standing, anticipatory postural adjustments (APAs) and focal movements are delayed while performing a choice reaction task, compared with a simple reaction task. We hypothesized that APAs and focal movements of a choice reaction task would be similarly delayed during walking. Furthermore, reaction times are delayed during walking compared with standing. We further hypothesized that APAs and focal movements would be delayed during walking, compared with standing, for both simple and choice reaction tasks. Subjects either walked or stood on a treadmill while holding on to stable handles. They were asked to push or pull on the handles in response to a visual cue. Muscle activity was recorded from muscles of the leg (APA) and arm (RT). Our results were in agreement with previous work showing APA onset was delayed in the choice reaction task compared with the simple reaction task. In addition, the interval between the onset of APA and focal movement activity increased with choice reaction tasks. The task of walking did not delay the onset of focal movement for either the simple or choice reaction tasks. Walking did delay the onset of the APA, but only during choice reaction tasks. The results suggest the added demand of walking does not significantly modify the control of focal arm movements. However, additional attentional demands while walking may compromise anticipatory postural control.

Behavioral Variability of Choices versus Structural Inconsistency of Preferences

ERIC Educational Resources Information Center

Regenwetter, Michel; Davis-Stober, Clintin P.

2012-01-01

Theories of rational choice often make the structural consistency assumption that every decision maker's binary strict preference among choice alternatives forms a "strict weak order". Likewise, the very concept of a "utility function" over lotteries in normative, prescriptive, and descriptive theory is mathematically equivalent to strict weak…

Theory of choice in bandit, information sampling and foraging tasks.

PubMed

Averbeck, Bruno B

2015-03-01

Decision making has been studied with a wide array of tasks. Here we examine the theoretical structure of bandit, information sampling and foraging tasks. These tasks move beyond tasks where the choice in the current trial does not affect future expected rewards. We have modeled these tasks using Markov decision processes (MDPs). MDPs provide a general framework for modeling tasks in which decisions affect the information on which future choices will be made. Under the assumption that agents are maximizing expected rewards, MDPs provide normative solutions. We find that all three classes of tasks pose choices among actions which trade-off immediate and future expected rewards. The tasks drive these trade-offs in unique ways, however. For bandit and information sampling tasks, increasing uncertainty or the time horizon shifts value to actions that pay-off in the future. Correspondingly, decreasing uncertainty increases the relative value of actions that pay-off immediately. For foraging tasks the time-horizon plays the dominant role, as choices do not affect future uncertainty in these tasks.

A Simple Artificial Life Model Explains Irrational Behavior in Human Decision-Making

PubMed Central

Feher da Silva, Carolina; Baldo, Marcus Vinícius Chrysóstomo

2012-01-01

Although praised for their rationality, humans often make poor decisions, even in simple situations. In the repeated binary choice experiment, an individual has to choose repeatedly between the same two alternatives, where a reward is assigned to one of them with fixed probability. The optimal strategy is to perseverate with choosing the alternative with the best expected return. Whereas many species perseverate, humans tend to match the frequencies of their choices to the frequencies of the alternatives, a sub-optimal strategy known as probability matching. Our goal was to find the primary cognitive constraints under which a set of simple evolutionary rules can lead to such contrasting behaviors. We simulated the evolution of artificial populations, wherein the fitness of each animat (artificial animal) depended on its ability to predict the next element of a sequence made up of a repeating binary string of varying size. When the string was short relative to the animats’ neural capacity, they could learn it and correctly predict the next element of the sequence. When it was long, they could not learn it, turning to the next best option: to perseverate. Animats from the last generation then performed the task of predicting the next element of a non-periodical binary sequence. We found that, whereas animats with smaller neural capacity kept perseverating with the best alternative as before, animats with larger neural capacity, which had previously been able to learn the pattern of repeating strings, adopted probability matching, being outperformed by the perseverating animats. Our results demonstrate how the ability to make predictions in an environment endowed with regular patterns may lead to probability matching under less structured conditions. They point to probability matching as a likely by-product of adaptive cognitive strategies that were crucial in human evolution, but may lead to sub-optimal performances in other environments. PMID:22563454

A simple artificial life model explains irrational behavior in human decision-making.

PubMed

Feher da Silva, Carolina; Baldo, Marcus Vinícius Chrysóstomo

2012-01-01

Although praised for their rationality, humans often make poor decisions, even in simple situations. In the repeated binary choice experiment, an individual has to choose repeatedly between the same two alternatives, where a reward is assigned to one of them with fixed probability. The optimal strategy is to perseverate with choosing the alternative with the best expected return. Whereas many species perseverate, humans tend to match the frequencies of their choices to the frequencies of the alternatives, a sub-optimal strategy known as probability matching. Our goal was to find the primary cognitive constraints under which a set of simple evolutionary rules can lead to such contrasting behaviors. We simulated the evolution of artificial populations, wherein the fitness of each animat (artificial animal) depended on its ability to predict the next element of a sequence made up of a repeating binary string of varying size. When the string was short relative to the animats' neural capacity, they could learn it and correctly predict the next element of the sequence. When it was long, they could not learn it, turning to the next best option: to perseverate. Animats from the last generation then performed the task of predicting the next element of a non-periodical binary sequence. We found that, whereas animats with smaller neural capacity kept perseverating with the best alternative as before, animats with larger neural capacity, which had previously been able to learn the pattern of repeating strings, adopted probability matching, being outperformed by the perseverating animats. Our results demonstrate how the ability to make predictions in an environment endowed with regular patterns may lead to probability matching under less structured conditions. They point to probability matching as a likely by-product of adaptive cognitive strategies that were crucial in human evolution, but may lead to sub-optimal performances in other environments.

Effects of cues in a binary categorization task on dual-task performance, mental workload, and effort.

PubMed

Botzer, Assaf; Meyer, Joachim; Parmet, Yisrael

2016-09-01

Binary cues help operators perform binary categorization tasks, such as monitoring for system failures. They may also allow them to attend to other tasks they concurrently perform. If the time saved by using cues is allocated to other concurrent tasks, users' overall effort may remain unchanged. In 2 experiments, participants performed a simulated quality control task, together with a tracking task. In half the experimental blocks cues were available, and participants could use them in their decisions about the quality of products (intact or faulty). In Experiment 1, the difficulty of tracking was constant, while in Experiment 2, tracking difficulty differed in the 2 halves of the experiment. In both experiments, participants reported on the NASA Task Load Index that cues improved their performance and reduced their frustration. Consequently, their overall score on mental workload (MWL) was lower with cues. They also reported, however, that cues did not reduce their effort. We conclude that cues and other forms of automation may support task performance and reduce overall MWL, but this will not necessarily mean that users will work less hard. Thus, effort and overall MWL should be evaluated separately, if one wants to obtain a full picture of the effects of automation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Stimulus ambiguity elicits response conflict.

PubMed

Szmalec, Arnaud; Verbruggen, Frederick; Vandierendonck, André; De Baene, Wouter; Verguts, Tom; Notebaert, Wim

2008-04-18

Conflict monitoring theory [M.M. Botvinick, T. Braver, D. Barch, C. Carter, J.D. Cohen, Conflict monitoring and cognitive control, Psychol. Rev. 108 (2001) 625-652] assumes that perceptual ambiguity among choice stimuli elicits response conflict in choice reaction. It hence predicts that response conflict is also involved in elementary variants of choice reaction time (RT) tasks, i.e., those variants that, by contrast with the Stroop task or the Go/No-Go task for instance, are rarely associated with cognitive control. In order to test this prediction, an experiment was designed in which participants performed a simple RT task and a regular between-hand 2-choice RT task under three different levels of stimulus ambiguity. The data show that response conflict, as measured by the N2 component of the event-related brain potential (ERP), was elicited in the 2-choice RT task but not in the simple RT task and that the degree of response conflict in the 2-choice RT task was a function of stimulus ambiguity. These results show that response conflict is also present in a regular choice RT task which is traditionally not considered to be a measure of cognitive conflict.

Articulation, Transfer, and Student Choice in a Binary Post-Secondary System

ERIC Educational Resources Information Center

Lang, Daniel W.

2009-01-01

This paper investigates the intersection of system articulation, transfer, and the choices that secondary school students make when they apply to college and university. The investigation is based on the results of a study that was undertaken to determine factors that influence choices that secondary school students make between enrolling in…

Modeling the Effect of Enlarging Seating Room on Passengers' Preference of Taiwan's Domestic Airlines

NASA Technical Reports Server (NTRS)

Lu, Jin-Long; Tsai, Li-Non

2003-01-01

This study addresses the need for measuring the effect of enlarging seating room in airplane on passengers' preferences of airline in Taiwan. The results can assist Taiwan's domestic air carriers in better understanding their customers' expectations. Stated choice experiment is used to incorporate passengers' trade-offs in the preferred measurement, and three major attributes are taken into account in the stated choice experiment: (1) type of seat (enlarged or not), (2) price, and (3) brand names of airlines. Furthermore, a binary logit model is used to model the choice behavior of air passengers. The findings show that the type of seat is a major significant variable; price and airline's brand are also significant as well. It concludes that air carriers should put more emphasis on the issue of improving the quality of seat comfort. Keywords: Passengers' preference, Enlarged seating room, Stated choice experiment, Binary logit model.

Performance monitoring and response conflict resolution associated with choice stepping reaction tasks.

PubMed

Watanabe, Tatsunori; Tsutou, Kotaro; Saito, Kotaro; Ishida, Kazuto; Tanabe, Shigeo; Nojima, Ippei

2016-11-01

Choice reaction requires response conflict resolution, and the resolution processes that occur during a choice stepping reaction task undertaken in a standing position, which requires maintenance of balance, may be different to those processes occurring during a choice reaction task performed in a seated position. The study purpose was to investigate the resolution processes during a choice stepping reaction task at the cortical level using electroencephalography and compare the results with a control task involving ankle dorsiflexion responses. Twelve young adults either stepped forward or dorsiflexed the ankle in response to a visual imperative stimulus presented on a computer screen. We used the Simon task and examined the error-related negativity (ERN) that follows an incorrect response and the correct-response negativity (CRN) that follows a correct response. Error was defined as an incorrect initial weight transfer for the stepping task and as an incorrect initial tibialis anterior activation for the control task. Results revealed that ERN and CRN amplitudes were similar in size for the stepping task, whereas the amplitude of ERN was larger than that of CRN for the control task. The ERN amplitude was also larger in the stepping task than the control task. These observations suggest that a choice stepping reaction task involves a strategy emphasizing post-response conflict and general performance monitoring of actual and required responses and also requires greater cognitive load than a choice dorsiflexion reaction. The response conflict resolution processes appear to be different for stepping tasks and reaction tasks performed in a seated position.

Context influences decision-making in boys with attention-deficit/hyperactivity disorder: A comparison of traditional and novel choice-impulsivity paradigms.

PubMed

Patros, Connor H G; Alderson, R Matt; Lea, Sarah E; Tarle, Stephanie J

2017-02-01

Attention-deficit/hyperactivity disorder (ADHD) is characterized by an impaired ability to maintain attention and/or hyperactivity/impulsivity. Impulsivity is frequently defined as the preference for small, immediate rewards over larger, delayed rewards, and has been associated with a variety of negative outcomes such as risky behavior and academic difficulty. Extant studies have uniformly utilized the traditional paradigm of presenting two response choices, which limits the generalization of findings to scenarios in which children/adolescents are faced with dichotomous decisions. The current study is the first to examine the effect of manipulating the number of available response options on impulsive decision-making in boys with and without ADHD. A total of 39 boys (ADHD = 16, typically developing [TD] = 23) aged 8-12 years completed a traditional two-choice impulsivity task and a novel five-choice impulsivity task to examine the effect of manipulating the number of choice responses (two vs five) on impulsive decision-making. A five-choice task was utilized as it presents a more continuous array of choice options when compared to the typical two-choice task, and is comparable given its methodological similarity to the two-choice task. Results suggested that boys with ADHD were significantly more impulsive than TD boys during the two-choice task, but not during the five-choice task. Collectively, these findings suggest that ADHD-related impulsivity is not ubiquitous, but rather dependent on variation in demands and/or context. Further, these findings highlight the importance of examining ADHD-related decision-making within the context of alternative paradigms, as the exclusive utilization of two-choice tasks may promote inaccurate conceptualizations of the disorder.

Individual differences in impulsive and risky choice: effects of environmental rearing conditions.

PubMed

Kirkpatrick, Kimberly; Marshall, Andrew T; Smith, Aaron P; Koci, Juraj; Park, Yoonseong

2014-08-01

The present experiment investigated early-rearing environment modulation of individual differences in impulsive and risky choice. Rats were reared in an isolated condition (IC; n=12), in which they lived alone without novel stimuli, or an enriched condition (EC; n=11), in which they lived among conspecifics with novel stimuli. The impulsive choice task involved choices between smaller-sooner (SS) versus larger-later (LL) rewards. The risky choice task involved choices between certain-smaller (C-S) versus uncertain-larger (U-L) rewards. Following choice testing, incentive motivation to work for food was measured using a progressive ratio task and correlated with choice behavior. HPLC analyses were conducted to determine how monoamine concentrations within the prefrontal cortex (PFC) and nucleus accumbens (NAC) related to behavior in different tasks. IC rats were more impulsive than EC rats, but they did not differ in risky choice behavior. However, choice behavior across tasks was significantly correlated (i.e., the more impulsive rats were also riskier). There were no group differences in monoamine levels, but noradrenergic and serotonergic concentrations were significantly correlated with impulsive and risky choice. Furthermore, serotonin and norepinephrine concentrations in the NAC significantly correlated with incentive motivation and the timing of the reward delays within the choice tasks. These results suggest a role for domain general processes in impulsive and risky choice and indicate the importance of the NAC and/or PFC in timing, reward processing, and choice behavior. Copyright © 2014 Elsevier B.V. All rights reserved.

Individual differences in impulsive and risky choice: Effects of environmental rearing conditions

PubMed Central

Kirkpatrick, Kimberly; Marshall, Andrew T.; Smith, Aaron P.; Koci, Juraj; Park, Yoonseong

2014-01-01

The present experiment investigated early-rearing environment modulation of individual differences in impulsive and risky choice. Rats were reared in an isolated condition (IC; n = 12), in which they lived alone without novel stimuli, or an enriched condition (EC; n = 12), in which they lived among conspecifics with novel stimuli. The impulsive choice task involved choices between smaller-sooner (SS) versus larger-later (LL) rewards. The risky choice task involved choices between certain-smaller (C-S) versus uncertain-larger (U-L) rewards. Following choice testing, incentive motivation to work for food was measured using a progressive ratio task and correlated with choice behavior. HPLC analyses were conducted to determine how monoamine concentrations within the prefrontal cortex (PFC) and nucleus accumbens (NAC) related to behavior in different tasks. IC rats were more impulsive than EC rats, but they did not differ in risky choice behavior. However, choice behavior across tasks was significantly correlated (i.e., the more impulsive rats were also riskier). There were no group differences in monoamine levels, but noradrenergic and serotonergic concentrations were significantly correlated with impulsive and risky choice. Furthermore, serotonin and norepinephrine concentrations in the NAC significantly correlated with incentive motivation and the timing of the reward delays within the choice tasks. These results suggest a role for domain general processes in impulsive and risky choice and indicate the importance of the NAC and/or PFC in timing, reward processing, and choice behavior. PMID:24769268

The downside of choice: Having a choice benefits enjoyment, but at a cost to efficiency and time in visual search.

PubMed

Kunar, Melina A; Ariyabandu, Surani; Jami, Zaffran

2016-04-01

The efficiency of how people search for an item in visual search has, traditionally, been thought to depend on bottom-up or top-down guidance cues. However, recent research has shown that the rate at which people visually search through a display is also affected by cognitive strategies. In this study, we investigated the role of choice in visual search, by asking whether giving people a choice alters both preference for a cognitively neutral task and search behavior. Two visual search conditions were examined: one in which participants were given a choice of visual search task (the choice condition), and one in which participants did not have a choice (the no-choice condition). The results showed that the participants in the choice condition rated the task as both more enjoyable and likeable than did the participants in the no-choice condition. However, despite their preferences, actual search performance was slower and less efficient in the choice condition than in the no-choice condition (Exp. 1). Experiment 2 showed that the difference in search performance between the choice and no-choice conditions disappeared when central executive processes became occupied with a task-switching task. These data concur with a choice-impaired hypothesis of search, in which having a choice leads to more motivated, active search involving executive processes.

Semiparametric Thurstonian Models for Recurrent Choices: A Bayesian Analysis

ERIC Educational Resources Information Center

Ansari, Asim; Iyengar, Raghuram

2006-01-01

We develop semiparametric Bayesian Thurstonian models for analyzing repeated choice decisions involving multinomial, multivariate binary or multivariate ordinal data. Our modeling framework has multiple components that together yield considerable flexibility in modeling preference utilities, cross-sectional heterogeneity and parameter-driven…

Nucleus accumbens core lesions induce sub-optimal choice and reduce sensitivity to magnitude and delay in impulsive choice tasks

PubMed Central

Steele, Catherine C.; Peterson, Jennifer R.; Marshall, Andrew T.; Stuebing, Sarah L.; Kirkpatrick, Kimberly

2017-01-01

The nucleus accumbens core (NAc) has long been recognized as an important contributor to the computation of reward value that is critical for impulsive choice behavior. Impulsive choice refers to choosing a smaller-sooner (SS) over a larger-later (LL) reward when the LL is more optimal in terms of the rate of reward delivery. Two experiments examined the role of the NAc in impulsive choice and its component processes of delay and magnitude processing. Experiment 1 delivered an impulsive choice task with manipulations of LL reward magnitude, followed by a reward magnitude discrimination task. Experiment 2 tested impulsive choice under manipulations of LL delay, followed by temporal bisection and progressive interval tasks. NAc lesions, in comparison to sham control lesions, produced suboptimal preferences that resulted in lower reward earning rates, and led to reduced sensitivity to magnitude and delay within the impulsive choice task. The secondary tasks revealed intact reward magnitude and delay discrimination abilities, but the lesion rats persisted in responding more as the progressive interval increased during the session. The results suggest that the NAc is most critical for demonstrating good sensitivity to magnitude and delay, and adjusting behavior accordingly. Ultimately, the NAc lesions induced suboptimal choice behavior rather than simply promoting impulsive choice, suggesting that an intact NAc is necessary for optimal decision making. PMID:29146281

An enquiry into the method of paired comparison: reliability, scaling, and Thurstone's Law of Comparative Judgment

Treesearch

Thomas C. Brown; George L. Peterson

2009-01-01

The method of paired comparisons is used to measure individuals' preference orderings of items presented to them as discrete binary choices. This paper reviews the theory and application of the paired comparison method, describes a new computer program available for eliciting the choices, and presents an analysis of methods for scaling paired choice data to...

Aniracetam restores motivation reduced by satiation in a choice reaction task in aged rats.

PubMed

Nakamura, K; Kurasawa, M

2001-01-01

This study aims to examine the effects of aniracetam on satiation-induced poor performance in a choice reaction task. Aged rats that mastered the task under food restriction stably maintained the task performance for a long period. Satiation by successive free feeding greatly diminished the performance. Satiation resulted in a decreased % correct, increased % omission and prolonged choice reaction time, indicating a reduction in lever response with low choice accuracy and slow responding speed. Repeated administration of aniracetam (30 mg/kg, po, for 14 days) partially recovered the choice accuracy and lever response, but not the responding speed, task-associated motor activity or impulsivity. In addition, aniracetam did not affect the animals' weights. These results indicate that satiation reduces motivation to perform and attain the task. Aniracetam may restore motivation, probably by improving poor behavioral states (daily attentional and vigilance failures), thereby creating the driving force.

Influence of multiple categories on the prediction of unknown properties

PubMed Central

Verde, Michael F.; Murphy, Gregory L.; Ross, Brian H.

2006-01-01

Knowing an item's category helps us predict its unknown properties. Previous studies suggest that when asked to evaluate the probability of an unknown property, people tend to consider only an item's most likely category, ignoring alternative categories. In the present study, property prediction took the form of either a probability rating or a speeded, binary-choice judgment. Consistent with past findings, subjects ignored alternative categories in their probability ratings. However, their binary-choice judgments were influenced by alternative categories. This novel finding suggests that the way category knowledge is used in prediction depends critically on the form of the prediction. PMID:16156183

Binary and ternary gas mixtures for use in glow discharge closing switches

DOEpatents

Hunter, Scott R.; Christophorou, Loucas G.

1990-01-01

Highly efficient binary and ternary gas mixtures for use in diffuse glow discharge closing switches are disclosed. The binary mixtures are combinations of helium or neon and selected perfluorides. The ternary mixtures are combinations of helium, neon, or argon, a selected perfluoride, and a small amount of gas that exhibits enhanced ionization characteristics. These mixtures are shown to be the optimum choices for use in diffuse glow discharge closing switches by virtue of the combined physio-electric properties of the mixture components.

Sex differences in the Kimchi-Palmer task revisited: Global reaction times, but not number of global choices differ between adult men and women.

PubMed

Scheuringer, Andrea; Pletzer, Belinda

2016-10-15

Research, directly assessing sex-dependent differences in global versus local processing is sparse, but predominantly suggesting that men show a stronger global processing bias than women. Utilizing the Kimchi-Palmer task however, sex differences in the number of global choices can only be found in children, but not in adults. In the current study 52 men and 46 women completed a computerized version of the Kimchi Palmer task, in order to investigate whether sex-differences in global-local processing in the Kimchi-Palmer task are reflected in choice reaction times rather than choices per se. While no sex differences were found in the number of global choices, we found that especially women are faster in making local choices than men, while men are faster in making global choices than women. We did not find support for the assumption that this sex difference was modulated by menstrual cycle phase of women, since the difference between reaction times to global and local choices was consistent across the menstrual cycle of women. Accordingly there was no relationship between progesterone and global-local processing in the Kimchi-Palmer task. However, like in studies utilizing the Navon task, testosterone was positively related to the number of global choices in both men and women. To our knowledge, this is the first study including reaction times as outcome measure in a Kimchi Palmer paradigm and also the first study demonstrating sex differences in the Kimchi Palmer task in adults. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Physiological Evidence for Response Inhibition in Choice Reaction Time Tasks

ERIC Educational Resources Information Center

Burle, Boris; Vidal, Frank; Tandonnet, Christophe; Hasbroucq, Thierry

2004-01-01

Inhibition is a widely used notion proposed to account for data obtained in choice reaction time (RT) tasks. However, this concept is weakly supported by empirical facts. In this paper, we review a series of experiments using Hoffman reflex, transcranial magnetic stimulation and electroencephalography to study inhibition in choice RT tasks. We…

Covert face recognition in congenital prosopagnosia: a group study.

PubMed

Rivolta, Davide; Palermo, Romina; Schmalzl, Laura; Coltheart, Max

2012-03-01

Even though people with congenital prosopagnosia (CP) never develop a normal ability to "overtly" recognize faces, some individuals show indices of "covert" (or implicit) face recognition. The aim of this study was to demonstrate covert face recognition in CP when participants could not overtly recognize the faces. Eleven people with CP completed three tasks assessing their overt face recognition ability, and three tasks assessing their "covert" face recognition: a Forced choice familiarity task, a Forced choice cued task, and a Priming task. Evidence of covert recognition was observed with the Forced choice familiarity task, but not the Priming task. In addition, we propose that the Forced choice cued task does not measure covert processing as such, but instead "provoked-overt" recognition. Our study clearly shows that people with CP demonstrate covert recognition for faces that they cannot overtly recognize, and that behavioural tasks vary in their sensitivity to detect covert recognition in CP. Copyright © 2011 Elsevier Srl. All rights reserved.

Precision of proportion estimation with binary compressed Raman spectrum.

PubMed

Réfrégier, Philippe; Scotté, Camille; de Aguiar, Hilton B; Rigneault, Hervé; Galland, Frédéric

2018-01-01

The precision of proportion estimation with binary filtering of a Raman spectrum mixture is analyzed when the number of binary filters is equal to the number of present species and when the measurements are corrupted with Poisson photon noise. It is shown that the Cramer-Rao bound provides a useful methodology to analyze the performance of such an approach, in particular when the binary filters are orthogonal. It is demonstrated that a simple linear mean square error estimation method is efficient (i.e., has a variance equal to the Cramer-Rao bound). Evolutions of the Cramer-Rao bound are analyzed when the measuring times are optimized or when the considered proportion for binary filter synthesis is not optimized. Two strategies for the appropriate choice of this considered proportion are also analyzed for the binary filter synthesis.

Measuring pilot workload in a motion base simulator. III - Synchronous secondary task

NASA Technical Reports Server (NTRS)

Kantowitz, Barry H.; Bortolussi, Michael R.; Hart, Sandra G.

1987-01-01

This experiment continues earlier research of Kantowitz et al. (1983) conducted in a GAT-1 motion-base trainer to evaluate choice-reaction secondary tasks as measures of pilot work load. The earlier work used an asynchronous secondary task presented every 22 sec regardless of flying performance. The present experiment uses a synchronous task presented only when a critical event occurred on the flying task. Both two- and four-choice visual secondary tasks were investigated. Analysis of primary flying-task results showed no decrement in error for altitude, indicating that the key assumption necessary for using a choice secondary task was satisfied. Reaction times showed significant differences between 'easy' and 'hard' flight scenarios as well as the ability to discriminate among flight tasks.

Predicting social and communicative ability in school-age children with autism spectrum disorder: A pilot study of the Social Attribution Task, Multiple Choice.

PubMed

Burger-Caplan, Rebecca; Saulnier, Celine; Jones, Warren; Klin, Ami

2016-11-01

The Social Attribution Task, Multiple Choice is introduced as a measure of implicit social cognitive ability in children, addressing a key challenge in quantification of social cognitive function in autism spectrum disorder, whereby individuals can often be successful in explicit social scenarios, despite marked social adaptive deficits. The 19-question Social Attribution Task, Multiple Choice, which presents ambiguous stimuli meant to elicit social attribution, was administered to children with autism spectrum disorder (N = 23) and to age-matched and verbal IQ-matched typically developing children (N = 57). The Social Attribution Task, Multiple Choice performance differed between autism spectrum disorder and typically developing groups, with typically developing children performing significantly better than children with autism spectrum disorder. The Social Attribution Task, Multiple Choice scores were positively correlated with age (r = 0.474) while being independent from verbal IQ (r = 0.236). The Social Attribution Task, Multiple Choice was strongly correlated with Vineland Adaptive Behavior Scales Communication (r = 0.464) and Socialization (r = 0.482) scores, but not with Daily Living Skills scores (r = 0.116), suggesting that the implicit social cognitive ability underlying performance on the Social Attribution Task, Multiple Choice is associated with real-life social adaptive function. © The Author(s) 2016.

From cookies to carrots; the effect of inhibitory control training on children's snack selections.

PubMed

Porter, L; Bailey-Jones, C; Priudokaite, G; Allen, S; Wood, K; Stiles, K; Parvin, O; Javaid, M; Verbruggen, F; Lawrence, N S

2018-05-01

Children consume too much sugar and not enough fruit and vegetables, increasing their risk of adverse health outcomes. Inhibitory control training (ICT) reduces children's and adults' intake of energy-dense foods in both laboratory and real-life settings. However, no studies have yet examined whether ICT can increase healthy food choice when energy-dense options are also available. We investigated whether a food-specific Go/No-Go task could influence the food choices of children aged 4-11, as measured by a hypothetical food choice task using healthy and unhealthy food images printed on cards. Participants played either an active game (healthy foods = 100% go, unhealthy foods = 100% no-go; Studies 1 & 2), a food control game (both healthy and unhealthy foods = 50% go, 50% no-go; Studies 1 & 2) or a non-food control game (sports equipment = 100% go, technology = 100% no-go; Study 2 only) followed by the choice task. In Study 2, food card choices were also measured before training to examine change in choices. A post-training real food choice task was added to check that choices made in the card-based task were representative of choices made when faced with real healthy and unhealthy foods. Overall, the active group chose the greatest number of healthy food cards. Study 2 confirmed that this was due to increases in healthy food card choice in this group only. Active group participants chose a greater number of healthy foods in the real food choice task compared to children in the non-food control group only. The results are discussed with reference to methodological issues and the development of future healthy eating interventions. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Using an abstract geometry in virtual reality to explore choice behaviour: visual flicker preferences in honeybees.

PubMed

Van De Poll, Matthew N; Zajaczkowski, Esmi L; Taylor, Gavin J; Srinivasan, Mandyam V; van Swinderen, Bruno

2015-11-01

Closed-loop paradigms provide an effective approach for studying visual choice behaviour and attention in small animals. Different flying and walking paradigms have been developed to investigate behavioural and neuronal responses to competing stimuli in insects such as bees and flies. However, the variety of stimulus choices that can be presented over one experiment is often limited. Current choice paradigms are mostly constrained as single binary choice scenarios that are influenced by the linear structure of classical conditioning paradigms. Here, we present a novel behavioural choice paradigm that allows animals to explore a closed geometry of interconnected binary choices by repeatedly selecting among competing objects, thereby revealing stimulus preferences in an historical context. We used our novel paradigm to investigate visual flicker preferences in honeybees (Apis mellifera) and found significant preferences for 20-25 Hz flicker and avoidance of higher (50-100 Hz) and lower (2-4 Hz) flicker frequencies. Similar results were found when bees were presented with three simultaneous choices instead of two, and when they were given the chance to select previously rejected choices. Our results show that honeybees can discriminate among different flicker frequencies and that their visual preferences are persistent even under different experimental conditions. Interestingly, avoided stimuli were more attractive if they were novel, suggesting that novelty salience can override innate preferences. Our recursive virtual reality environment provides a new approach to studying visual discrimination and choice behaviour in animals. © 2015. Published by The Company of Biologists Ltd.

Guessing versus Choosing an Upcoming Task

PubMed Central

Kleinsorge, Thomas; Scheil, Juliane

2016-01-01

We compared the effects of guessing vs. choosing an upcoming task. In a task-switching paradigm with four tasks, two groups of participants were asked to either guess or choose which task will be presented next under otherwise identical conditions. The upcoming task corresponded to participants’ guesses or choices in 75 % of the trials. However, only participants in the Choosing condition were correctly informed about this, whereas participants in the Guessing condition were told that tasks were determined at random. In the Guessing condition, we replicated previous findings of a pronounced reduction of switch costs in case of incorrect guesses. This switch cost reduction was considerably less pronounced with denied choices in the Choosing condition. We suggest that in the Choosing condition, the signaling of prediction errors associated with denied choices is attenuated because a certain proportion of denied choices is consistent with the overall representation of the situation as conveyed by task instructions. In the Guessing condition, in contrast, the mismatch of guessed and actual task is resolved solely on the level of individual trials by strengthening the representation of the actual task. PMID:27047423

Decomposing Task-Switching Costs with the Diffusion Model

ERIC Educational Resources Information Center

Schmitz, Florian; Voss, Andreas

2012-01-01

In four experiments, task-switching processes were investigated with variants of the alternating runs paradigm and the explicit cueing paradigm. The classical diffusion model for binary decisions (Ratcliff, 1978) was used to dissociate different components of task-switching costs. Findings can be reconciled with the view that task-switching…

A comparison of the performance of threshold criteria for binary classification in terms of predicted prevalence and Kappa

Treesearch

Elizabeth A. Freeman; Gretchen G. Moisen

2008-01-01

Modelling techniques used in binary classification problems often result in a predicted probability surface, which is then translated into a presence - absence classification map. However, this translation requires a (possibly subjective) choice of threshold above which the variable of interest is predicted to be present. The selection of this threshold value can have...

Role of accentuation in the selection/rejection task framing effect.

PubMed

Chen, Jing; Proctor, Robert W

2017-04-01

Procedure invariance is a basic assumption of rational theories of choice, however, it has been shown to be violated: Different response modes, or task frames, sometimes reveal opposite preferences. The current study focused on selection and rejection task frames, involving a unique type of problem with enriched and impoverished options, which has previously led to conflicting findings and theoretical explanations: the compatibility hypothesis (Shafir, 1993) and the accentuation hypothesis (Wedell, 1997). We examined the role of task frame by distinguishing these 2 hypotheses and evaluating the information-processing basis of the choices. Experiments conducted online (Experiments 1 and 3) and in-lab (Experiment 4 with eye-tracking technique) revealed a difference between the 2 task frames in the choice data (i.e., the task-framing effect) as a function of the relative attractiveness of the options. Also, this task-framing effect was not influenced by imposed time constraints (Experiments 5 and 6) and was similarly evident with a more direct measure for the option attractiveness (obtained in Experiment 7). Experiment 2, conducted in a lab setting with verbal-protocol requirements, yielded no task-framing effect, suggesting that a requirement to verbalize reasons for choice minimizes accentuation. With this exception, the choice data are in agreement with the accentuation hypothesis, and the combined findings in choice, decision time, task confusion, and eye-tracking data provide evidence of a basis in cognitive effort rather than motivation, as Wedell proposed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Binary and ternary gas mixtures for use in glow discharge closing switches

DOEpatents

Hunter, S.R.; Christophorou, L.G.

1988-04-27

Highly efficient binary and ternary gas mixtures for use in diffuse glow discharge closing switches are disclosed. The binary mixtures are combinations of helium or neon and selected perfluorides. The ternary mixtures are combinations of helium, neon, or argon, a selected perfluoride, and a small amount of gas that exhibits enhanced ionization characteristics. These mixtures are shown to be the optimum choices for use in diffuse glow discharge closing switches by virtue if the combines physio-electric properties of the mixture components. 9 figs.

Encoding and choice in the task span paradigm.

PubMed

Reiman, Kaitlin M; Weaver, Starla M; Arrington, Catherine M

2015-03-01

Cognitive control during sequences of planned behaviors requires both plan-level processes such as generating, maintaining, and monitoring the plan, as well as task-level processes such as selecting, establishing and implementing specific task sets. The task span paradigm (Logan in J Exp Psychol Gen 133:218-236, 2004) combines two common cognitive control paradigms, task switching and working memory span, to investigate the integration of plan-level and task-level processes during control of sequential behavior. The current study expands past task span research to include measures of encoding processes and choice behavior with volitional sequence generation, using the standard task span as well as a novel voluntary task span paradigm. In two experiments, we consider how sequence complexity, defined separately for plan-level and task-level complexity, influences sequence encoding (Experiment 1), sequence choice (Experiment 2), sequence memory, and task performance of planned sequences of action. Results indicate that participants were sensitive to sequence complexity, but that different aspects of behavior are most strongly influenced by different types of complexity. Hierarchical complexity at the plan level best predicts voluntary sequence generation and memory; while switch frequency at the task level best predicts encoding of externally defined sequences and task performance. Furthermore, performance RTs were similar for externally and internally defined plans, whereas memory was improved for internally defined sequences. Finally, participants demonstrated a significant sequence choice bias in the voluntary task span. Consistent with past research on choice behavior, volitional selection of plans was markedly influenced by both the ease of memory and performance.

An adaptive, individualized fMRI delay discounting procedure to increase flexibility and optimize scanner time.

PubMed

Koffarnus, Mikhail N; Deshpande, Harshawardhan U; Lisinski, Jonathan M; Eklund, Anders; Bickel, Warren K; LaConte, Stephen M

2017-11-01

Research on the rate at which people discount the value of future rewards has become increasingly prevalent as discount rate has been shown to be associated with many unhealthy patterns of behavior such as drug abuse, gambling, and overeating. fMRI research points to a fronto-parietal-limbic pathway that is active during decisions between smaller amounts of money now and larger amounts available after a delay. Researchers in this area have used different variants of delay discounting tasks and reported various contrasts between choice trials of different types from these tasks. For instance, researchers have compared 1) choices of delayed monetary amounts to choices of the immediate monetary amounts, 2) 'hard' choices made near one's point of indifference to 'easy' choices that require little thought, and 3) trials where an immediate choice is available versus trials where one is unavailable, regardless of actual eventual choice. These differences in procedure and analysis make comparison of results across studies difficult. In the present experiment, we designed a delay discounting task with the intended capability of being able to construct contrasts of all three comparisons listed above while optimizing scanning time to reduce costs and avoid participant fatigue. This was accomplished with an algorithm that customized the choice trials presented to each participant with the goal of equalizing choice trials of each type. We compared this task, which we refer to here as the individualized discounting task (IDT), to two other delay discounting tasks previously reported in the literature (McClure et al., 2004; Amlung et al., 2014) in 18 participants. Results show that the IDT can examine each of the three contrasts mentioned above, while yielding a similar degree of activation as the reference tasks. This suggests that this new task could be used in delay discounting fMRI studies to allow researchers to more easily compare their results to a majority of previous research while minimizing scanning duration. Copyright © 2017 Elsevier Inc. All rights reserved.

The Stability and Consequences of Young Children's Same-Sex Peer Interactions.

ERIC Educational Resources Information Center

Martin, Carol Lynn; Fabes, Richard A.

2001-01-01

Examined whether preschool children's play-partner choices were stable over time and how they influenced behavior. Found that partner preferences were highly sex differentiated and stable over time. Identified two types of consequences of partner choice: a binary effect that influenced differences between the sexes and a social dosage effect that…

Stimulus similarity determines the prevalence of behavioral laterality in a visual discrimination task for mice

PubMed Central

Treviño, Mario

2014-01-01

Animal choices depend on direct sensory information, but also on the dynamic changes in the magnitude of reward. In visual discrimination tasks, the emergence of lateral biases in the choice record from animals is often described as a behavioral artifact, because these are highly correlated with error rates affecting psychophysical measurements. Here, we hypothesized that biased choices could constitute a robust behavioral strategy to solve discrimination tasks of graded difficulty. We trained mice to swim in a two-alterative visual discrimination task with escape from water as the reward. Their prevalence of making lateral choices increased with stimulus similarity and was present in conditions of high discriminability. While lateralization occurred at the individual level, it was absent, on average, at the population level. Biased choice sequences obeyed the generalized matching law and increased task efficiency when stimulus similarity was high. A mathematical analysis revealed that strongly-biased mice used information from past rewards but not past choices to make their current choices. We also found that the amount of lateralized choices made during the first day of training predicted individual differences in the average learning behavior. This framework provides useful analysis tools to study individualized visual-learning trajectories in mice. PMID:25524257

The Effects of Task Fluency and Concurrent Reinforcement Schedules on Student Choice Allocation between Math Tasks

ERIC Educational Resources Information Center

Zaman, Maliha

2010-01-01

Students may avoid working on difficult tasks because it takes them longer to complete those tasks, which results in a delay to reinforcement. Research studies show that reinforcer and response dimensions can be manipulated within a concurrent operants framework to bias choice allocation toward more difficult tasks. The current study extends…

Reliable binary cell-fate decisions based on oscillations

NASA Astrophysics Data System (ADS)

Pfeuty, B.; Kaneko, K.

2014-02-01

Biological systems have often to perform binary decisions under highly dynamic and noisy environments, such as during cell-fate determination. These decisions can be implemented by two main bifurcation mechanisms based on the transitions from either monostability or oscillation to bistability. We compare these two mechanisms by using stochastic models with time-varying fields and by establishing asymptotic formulas for the choice probabilities. Different scaling laws for decision sensitivity with respect to noise strength and signal timescale are obtained, supporting a role for oscillatory dynamics in performing noise-robust and temporally tunable binary decision-making. This result provides a rationale for recent experimental evidences showing that oscillatory expression of proteins often precedes binary cell-fate decisions.

Choose, rate or squeeze: Comparison of economic value functions elicited by different behavioral tasks

PubMed Central

Pessiglione, Mathias

2017-01-01

A standard view in neuroeconomics is that to make a choice, an agent first assigns subjective values to available options, and then compares them to select the best. In choice tasks, these cardinal values are typically inferred from the preference expressed by subjects between options presented in pairs. Alternatively, cardinal values can be directly elicited by asking subjects to place a cursor on an analog scale (rating task) or to exert a force on a power grip (effort task). These tasks can vary in many respects: they can notably be more or less costly and consequential. Here, we compared the value functions elicited by choice, rating and effort tasks on options composed of two monetary amounts: one for the subject (gain) and one for a charity (donation). Bayesian model selection showed that despite important differences between the three tasks, they all elicited a same value function, with similar weighting of gain and donation, but variable concavity. Moreover, value functions elicited by the different tasks could predict choices with equivalent accuracy. Our finding therefore suggests that comparable value functions can account for various motivated behaviors, beyond economic choice. Nevertheless, we report slight differences in the computational efficiency of parameter estimation that may guide the design of future studies. PMID:29161252

Depressive states amplify both upward and downward counterfactual thinking.

PubMed

Feng, Xue; Gu, Ruolei; Liang, Fucheng; Broster, Lucas S; Liu, Yunzhe; Zhang, Dandan; Luo, Yue-jia

2015-08-01

Depression has been linked to counterfactual thinking in many behavioral studies, but the direction of this effect remains disputed. In the current study, the relationship between depression and counterfactual thinking was examined using the event-related potential (ERP) technique. In a binary choice gambling task, outcome feedback of the chosen option and that of the alternative option were both provided, so as to elicit the process of counterfactual comparison. By investigating ERP signals in response to outcome presentation, we discovered that when the fictive outcome was better or worse than the factual outcome, the amplitude of the P3 component was positively correlated with individual levels of depression, but not levels of anxiety. These results indicate that depression strengthens both upward counterfactual thinking and downward counterfactual thinking. The implication of this finding to clinical research is discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

Do monkeys choose to choose?

PubMed

Perdue, Bonnie M; Evans, Theodore A; Washburn, David A; Rumbaugh, Duane M; Beran, Michael J

2014-06-01

Both empirical and anecdotal evidence supports the idea that choice is preferred by humans. Previous research has demonstrated that this preference extends to nonhuman animals, but it remains largely unknown whether animals will actively seek out or prefer opportunities to choose. Here we explored the issue of whether capuchin and rhesus monkeys choose to choose. We used a modified version of the SELECT task-a computer program in which monkeys can choose the order of completion of various psychomotor and cognitive tasks. In the present experiments, each trial began with a choice between two icons, one of which allowed the monkey to select the order of task completion, and the other of which led to the assignment of a task order by the computer. In either case, subjects still had to complete the same number of tasks and the same number of task trials. The tasks were relatively easy, and the monkeys responded correctly on most trials. Thus, global reinforcement rates were approximately equated across conditions. The only difference was whether the monkey chose the task order or it was assigned, thus isolating the act of choosing. Given sufficient experience with the task icons, all monkeys showed a significant preference for choice when the alternative was a randomly assigned order of tasks. To a lesser extent, some of the monkeys maintained a preference for choice over a preferred, but computer-assigned, task order that was yoked to their own previous choice selection. The results indicated that monkeys prefer to choose when all other aspects of the task are equated.

Learning the ideal observer for SKE detection tasks by use of convolutional neural networks (Cum Laude Poster Award)

NASA Astrophysics Data System (ADS)

Zhou, Weimin; Anastasio, Mark A.

2018-03-01

It has been advocated that task-based measures of image quality (IQ) should be employed to evaluate and optimize imaging systems. Task-based measures of IQ quantify the performance of an observer on a medically relevant task. The Bayesian Ideal Observer (IO), which employs complete statistical information of the object and noise, achieves the upper limit of the performance for a binary signal classification task. However, computing the IO performance is generally analytically intractable and can be computationally burdensome when Markov-chain Monte Carlo (MCMC) techniques are employed. In this paper, supervised learning with convolutional neural networks (CNNs) is employed to approximate the IO test statistics for a signal-known-exactly and background-known-exactly (SKE/BKE) binary detection task. The receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) are compared to those produced by the analytically computed IO. The advantages of the proposed supervised learning approach for approximating the IO are demonstrated.

Young children do not succeed in choice tasks that imply evaluating chances.

PubMed

Girotto, Vittorio; Fontanari, Laura; Gonzalez, Michel; Vallortigara, Giorgio; Blaye, Agnès

2016-07-01

Preverbal infants manifest probabilistic intuitions in their reactions to the outcomes of simple physical processes and in their choices. Their ability conflicts with the evidence that, before the age of about 5years, children's verbal judgments do not reveal probability understanding. To assess these conflicting results, three studies tested 3-5-year-olds on choice tasks on which infants perform successfully. The results showed that children of all age groups made optimal choices in tasks that did not require forming probabilistic expectations. In probabilistic tasks, however, only 5-year-olds made optimal choices. Younger children performed at random and/or were guided by superficial heuristics. These results suggest caution in interpreting infants' ability to evaluate chance, and indicate that the development of this ability may not follow a linear trajectory. Copyright © 2016 Elsevier B.V. All rights reserved.

The Effects of Study Tasks in a Computer-Based Chemistry Learning Environment

NASA Astrophysics Data System (ADS)

Urhahne, Detlef; Nick, Sabine; Poepping, Anna Christin; Schulz, Sarah Jayne

2013-12-01

The present study examines the effects of different study tasks on the acquisition of knowledge about acids and bases in a computer-based learning environment. Three different task formats were selected to create three treatment conditions: learning with gap-fill and matching tasks, learning with multiple-choice tasks, and learning only from text and figures without any additional tasks. Participants were 196 ninth-grade students who learned with a self-developed multimedia program in a pretest-posttest control group design. Research results reveal that gap-fill and matching tasks were most effective in promoting knowledge acquisition, followed by multiple-choice tasks, and no tasks at all. The findings are in line with previous research on this topic. The effects can possibly be explained by the generation-recognition model, which predicts that gap-fill and matching tasks trigger more encompassing learning processes than multiple-choice tasks. It is concluded that instructional designers should incorporate more challenging study tasks for enhancing the effectiveness of computer-based learning environments.

Evidence for age-related changes to temporal attention and memory from the choice time production task

PubMed Central

Gooch, Cynthia M.; Stern, Yaakov; Rakitin, Brian C.

2009-01-01

The effect of aging on interval timing was examined using a choice time production task, which required participants to choose a key response based on the location of the stimulus, but to delay responding until after a learned time interval. Experiment 1 varied attentional demands of the response choice portion of the task by varying difficulty of stimulus-response mapping. Choice difficulty affected temporal accuracy equally in both age groups, but older participants’ response latencies were more variable under more difficult response choice conditions. Experiment 2 tested the contribution of long-term memory to differences in choice time production between age groups over 3 days of testing. Direction of errors in time production between the two age groups diverged over the 3 sessions, but variability did not differ. Results from each experiment separately show age-related changes to attention and memory in temporal processing using different measures and manipulations in the same task. PMID:19132578

Interference effects of vocalization on dual task performance

NASA Astrophysics Data System (ADS)

Owens, J. M.; Goodman, L. S.; Pianka, M. J.

1984-09-01

Voice command and control systems have been proposed as a potential means of off-loading the typically overburdened visual information processing system. However, prior to introducing novel human-machine interfacing technologies in high workload environments, consideration must be given to the integration of the new technologists within existing task structures to ensure that no new sources of workload or interference are systematically introduced. This study examined the use of voice interactive systems technology in the joint performance of two cognitive information processing tasks requiring continuous memory and choice reaction wherein a basis for intertask interference might be expected. Stimuli for the continuous memory task were presented aurally and either voice or keyboard responding was required in the choice reaction task. Performance was significantly degraded in each task when voice responding was required in the choice reaction time task. Performance degradation was evident in higher error scores for both the choice reaction and continuous memory tasks. Performance decrements observed under conditions of high intertask stimulus similarity were not statistically significant. The results signal the need to consider further the task requirements for verbal short-term memory when applying speech technology in multitask environments.

Korean College EFL Learners' Task Motivation in Written Language Production

ERIC Educational Resources Information Center

Kim, Bomin; Kim, Haedong

2016-01-01

The aims of the present study were to explore the effects of two different types of task conditions (topic choice vs. no choice) on the quality of written production in a second language (lexical complexity, syntactic complexity, and cohesion) and to investigate the effects of these two different task conditions on task motivation. This research…

Rejection or selection: influence of framing in investment decisions.

PubMed

Cheng, Pi-Yueh; Chiou, Wen-Bin

2010-02-01

According to prospect theory, reflection effects result in preferences for risk-averse choices in gain situations and risk-seeking choices in loss situations. However, relevant literature in regard to decision making has suggested that positive information receives more weight in a selection task, whereas negative information receives more weight in a rejection task. The present study examined whether the nature of a decision task (selection vs rejection) would moderate the reflection effects. Undergraduates (47 men, 49 women; M age = 20.5 yr., SD = 1.1), selected according to specific screening criteria, participated in an experimental study. Typical reflection effects were observed in both selection and rejection task conditions. More importantly, negative information (i.e., the information about probable loss in risky choice of gain situations and the information about certain loss in cautious choice of loss situations) provided in the context of a rejection task received more weight and resulted in more frequent endorsements of the cautious choice in gain situations and of the risky choice in loss situations. Hence, the findings suggest that a decision context characterized by rejection may expand the reflection effects and thereby provide important information about situations in which investment decisions occur in a context characterized by rejection.

Effect of diatomic molecular properties on binary laser pulse optimizations of quantum gate operations.

PubMed

Zaari, Ryan R; Brown, Alex

2011-07-28

The importance of the ro-vibrational state energies on the ability to produce high fidelity binary shaped laser pulses for quantum logic gates is investigated. The single frequency 2-qubit ACNOT(1) and double frequency 2-qubit NOT(2) quantum gates are used as test cases to examine this behaviour. A range of diatomics is sampled. The laser pulses are optimized using a genetic algorithm for binary (two amplitude and two phase parameter) variation on a discretized frequency spectrum. The resulting trends in the fidelities were attributed to the intrinsic molecular properties and not the choice of method: a discretized frequency spectrum with genetic algorithm optimization. This is verified by using other common laser pulse optimization methods (including iterative optimal control theory), which result in the same qualitative trends in fidelity. The results differ from other studies that used vibrational state energies only. Moreover, appropriate choice of diatomic (relative ro-vibrational state arrangement) is critical for producing high fidelity optimized quantum logic gates. It is also suggested that global phase alignment imposes a significant restriction on obtaining high fidelity regions within the parameter search space. Overall, this indicates a complexity in the ability to provide appropriate binary laser pulse control of diatomics for molecular quantum computing. © 2011 American Institute of Physics

Rapid target foraging with reach or gaze: The hand looks further ahead than the eye

PubMed Central

2017-01-01

Real-world tasks typically consist of a series of target-directed actions and often require choices about which targets to act on and in what order. Such choice behavior can be assessed from an optimal foraging perspective whereby target selection is shaped by a balance between rewards and costs. Here we evaluated such decision-making in a rapid movement foraging task. On a given trial, participants were presented with 15 targets of varying size and value and were instructed to harvest as much reward as possible by either moving a handle to the targets (hand task) or by briefly fixating them (eye task). The short trial duration enabled participants to harvest about half the targets, ensuring that total reward was due to choice behavior. We developed a probabilistic model to predict target-by-target harvesting choices that considered the rewards and movement-related costs (i.e., target distance and size) associated with the current target as well as future targets. In the hand task, in comparison to the eye task, target choice was more strongly influenced by movement-related costs and took into account a greater number of future targets, consistent with the greater costs associated with arm movement. In both tasks, participants exhibited near-optimal behaviour and in a constrained version of the hand task in which choices could only be based on target positions, participants consistently chose among the shortest movement paths. Our results demonstrate that people can rapidly and effectively integrate values and movement-related costs associated with current and future targets when sequentially harvesting targets. PMID:28683138

Female mate choice in convict cichlids is transitive and consistent with a self-referent directional preference

PubMed Central

2013-01-01

Introduction One of the most important decisions that an animal has to make in its life is choosing a mate. Although most studies in sexual selection assume that mate choice is rational, this assumption has not been tested seriously. A crucial component of rationality is that animals exhibit transitive choices: if an individual prefers option A over B, and B over C, then it also prefers A over C. Results We assessed transitivity in mate choice: 40 female convict cichlids had to make a series of binary choices between males of varying size. Ninety percent of females showed transitive choices. The mean preference index was significantly higher when a female chose between their most preferred and least preferred male (male 1 vs. male 3) compared to when they chose between males of adjacent ranks (1 vs. 2 or 2 vs. 3). The results are consistent with a simple underlying preference function leading to transitive choice: females preferred males about one third larger than themselves. This rule of thumb correctly predicted which male was preferred in 67% of the cases and the ordering in binary choices in 78% of cases. Conclusions This study provides the first evidence for strong stochastic transitivity in a context of mate choice. The females exhibited ordinal preferences and the direction and magnitude of these preferences could be predicted from a simple rule. The females do not necessarily compare two males to choose the best; it is sufficient to use a self-referent evaluation. Such a simple decision rule has important implications for the evolution of the mating strategies and it is consistent with patterns of assortative mating repeatedly observed at population level. PMID:24216003

Loss restlessness and gain calmness: durable effects of losses and gains on choice switching.

PubMed

Yechiam, Eldad; Zahavi, Gal; Arditi, Eli

2015-08-01

While the traditional conceptualization of the effect of losses focuses on bias in the subjective weight of losses compared with respective gains, some accounts suggest more global task-related effects of losses. Based on a recent attentional theory, we predicted a positive after-effect of losses on choice switching in later tasks. In two experimental studies, we found increased choice switching rates in tasks with losses compared to tasks with no losses. Additionally, this heightened shifting behavior was maintained in subsequent tasks that do not include losses, a phenomenon we refer to as "loss restlessness." Conversely, gains were found to have an opposite "calming" effect on choice switching. Surprisingly, the loss restlessness phenomenon was observed following an all-losses payoff regime but not after a task with symmetric mixed gains and losses. This suggests that the unresolved mental account following an all-losses regime increases search behavior. Potential implications to macro level phenomena, such as the leverage effect, are discussed.

The effect of learning climate on snack consumption and ego depletion among undergraduate students.

PubMed

Magaraggia, Christian; Dimmock, James A; Jackson, Ben

2013-10-01

We explored the effect of controlled and autonomous learning choices on the consumption of a high-energy snack food, and also examined whether snack consumption during a controlled choice learning activity could 'up-regulate' subsequent performance on a self-regulation task. Participants were randomly assigned to a controlled choice learning condition in which food was provided, a controlled choice learning condition in which food was not provided, or an autonomous choice learning condition in which food was provided. Results indicated that the autonomous choice group consumed significantly less snack food than the controlled-choice-and-food group. Participants in the autonomous choice condition also performed better on the subsequent self-regulation task than the controlled-choice-and-food group, even after controlling for the amount of food consumed. Furthermore, within the controlled-choice-and-food condition, there was no association between food consumption and subsequent self-regulation task performance. Discussion focuses on the potential impact of a controlled learning climate on snack food consumption and on the degradation of self-regulation capacities. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Toward a Choice-Based Judgment Bias Task for Horses.

PubMed

Hintze, Sara; Roth, Emma; Bachmann, Iris; Würbel, Hanno

2017-01-01

Judgment bias tasks for nonhuman animals are promising tools to assess emotional valence as a measure of animal welfare. In view of establishing a valid judgment bias task for horses, the present study aimed to evaluate 2 versions (go/no-go and active choice) of an auditory judgment bias task for horses in terms of acquisition learning and discrimination of ambiguous cues. Five mares and 5 stallions were randomly assigned to the 2 designs and trained for 10 trials per day to acquire different operant responses to a low-frequency tone and a high-frequency tone, respectively. Following acquisition learning, horses were tested on 4 days with 3 ambiguous-tone trials interspersed between the 10 high-tone and low-tone trials. All 5 go/no-go horses but only one active-choice horse successfully learned their task, indicating that it is more difficult to train horses on an active choice task than on a go/no-go task. During testing, however, go/no-go horses did not differentiate between the 3 different ambiguous cues, thereby making the validity of the test results questionable in terms of emotional valence.

Economic valuation by the method of paired comparison, with emphasis on evaluation of the transitivity axiom

Treesearch

George L. Peterson; Thomas C. Brown

1998-01-01

The paired comparison (PC) method is used to investigate reliability, transitivity, and decision time for binary choices among goods and sums of money. The PC method reveals inconsistent choices and yields individual preference order over the set of items being compared. The data reported support the transitivity assumption and demonstrate high reliability for...

Predictor Combination in Binary Decision-Making Situations

ERIC Educational Resources Information Center

McGrath, Robert E.

2008-01-01

Professional psychologists are often confronted with the task of making binary decisions about individuals, such as predictions about future behavior or employee selection. Test users familiar with linear models and Bayes's theorem are likely to assume that the accuracy of decisions is consistently improved by combination of outcomes across valid…

Task Values and Ability Beliefs as Predictors of High School Literacy Choices: A Developmental Analysis

ERIC Educational Resources Information Center

Durik, Amanda M.; Vida, Mina; Eccles, Jacquelynne S.

2005-01-01

This study examines how competence beliefs and task values predict high school achievement choices related to literacy. Students' task beliefs (self-concept of ability, intrinsic value, and importance) about reading in the 4th grade and English in the 10th grade were tracked over time. Task beliefs, school performance, and gender were used to…

Focused Attention Deficits in Patients with Alzheimer's Disease and Mild Cognitive Impairment

ERIC Educational Resources Information Center

Levinoff, E.J.; Saumier, D.; Chertkow, H.

2005-01-01

Reaction time (RT) tasks take various forms, and can assess psychomotor speed, (i.e., simple reaction time task), and focused attention (i.e., choice reaction time (CRT) task). If cues are provided before stimulus presentation (i.e., cued choice reaction time (CCRT) task), then a cueing effect can also be assessed. A limited number of studies have…

Impact of Bayesian Priors on the Characterization of Binary Black Hole Coalescences

NASA Astrophysics Data System (ADS)

Vitale, Salvatore; Gerosa, Davide; Haster, Carl-Johan; Chatziioannou, Katerina; Zimmerman, Aaron

2017-12-01

In a regime where data are only mildly informative, prior choices can play a significant role in Bayesian statistical inference, potentially affecting the inferred physics. We show this is indeed the case for some of the parameters inferred from current gravitational-wave measurements of binary black hole coalescences. We reanalyze the first detections performed by the twin LIGO interferometers using alternative (and astrophysically motivated) prior assumptions. We find different prior distributions can introduce deviations in the resulting posteriors that impact the physical interpretation of these systems. For instance, (i) limits on the 90% credible interval on the effective black hole spin χeff are subject to variations of ˜10 % if a prior with black hole spins mostly aligned to the binary's angular momentum is considered instead of the standard choice of isotropic spin directions, and (ii) under priors motivated by the initial stellar mass function, we infer tighter constraints on the black hole masses, and in particular, we find no support for any of the inferred masses within the putative mass gap M ≲5 M⊙.

Impact of Bayesian Priors on the Characterization of Binary Black Hole Coalescences.

PubMed

Vitale, Salvatore; Gerosa, Davide; Haster, Carl-Johan; Chatziioannou, Katerina; Zimmerman, Aaron

2017-12-22

In a regime where data are only mildly informative, prior choices can play a significant role in Bayesian statistical inference, potentially affecting the inferred physics. We show this is indeed the case for some of the parameters inferred from current gravitational-wave measurements of binary black hole coalescences. We reanalyze the first detections performed by the twin LIGO interferometers using alternative (and astrophysically motivated) prior assumptions. We find different prior distributions can introduce deviations in the resulting posteriors that impact the physical interpretation of these systems. For instance, (i) limits on the 90% credible interval on the effective black hole spin χ_{eff} are subject to variations of ∼10% if a prior with black hole spins mostly aligned to the binary's angular momentum is considered instead of the standard choice of isotropic spin directions, and (ii) under priors motivated by the initial stellar mass function, we infer tighter constraints on the black hole masses, and in particular, we find no support for any of the inferred masses within the putative mass gap M≲5  M_{⊙}.

Delay Choice vs. Delay Maintenance: Different Measures of Delayed Gratification in Capuchin Monkeys (Cebus apella)

PubMed Central

Addessi, Elsa; Paglieri, Fabio; Beran, Michael J.; Evans, Theodore A.; Macchitella, Luigi; De Petrillo, Francesca; Focaroli, Valentina

2013-01-01

Delaying gratification involves two components: (i) delay choice (selecting a delayed reward over an immediate one), and (ii) delay maintenance (sustaining the decision to delay gratification even if the immediate reward is available during the delay). In primates, two tasks most commonly have explored these components, the Intertemporal choice task and the Accumulation task. It is unclear whether these tasks provide equivalent measures of delay of gratification. Here, we compared the performance of the same capuchin monkeys, belonging to two study populations, between these tasks. We found only limited evidence of a significant correlation in performance. Consequently, in contrast to what is often assumed, our data provide only partial support to the hypothesis that these tasks provide equivalent measures of delay of gratification. PMID:23544770

Expanding the catalog of binary black-hole simulations: aligned-spin configurations

NASA Astrophysics Data System (ADS)

Chu, Tony; Pfeiffer, Harald; Scheel, Mark; Szilagyi, Bela; SXS Collaboration

2015-04-01

A major goal of numerical relativity is to model the inspiral and merger of binary black holes through sufficiently accurate and long simulations, to enable the successful detection of gravitational waves. However, covering the full parameter space of binary configurations is a computationally daunting task. The SXS Collaboration has made important progress in this direction recently, with a catalog of 174 publicly available binary black-hole simulations [black-holes.org/waveforms]. Nevertheless, the parameter-space coverage remains sparse, even for non-precessing binaries. In this talk, I will describe an addition to the SXS catalog to improve its coverage, consisting of 95 new simulations of aligned-spin binaries with moderate mass ratios and dimensionless spins as high as 0.9. Some applications of these new simulations will also be mentioned.

Do pet dogs (Canis familiaris) follow ostensive and non-ostensive human gaze to distant space and to objects?

PubMed

Duranton, Charlotte; Range, Friederike; Virányi, Zsófia

2017-07-01

Dogs are renowned for being skilful at using human-given communicative cues such as pointing. Results are contradictory, however, when it comes to dogs' following human gaze, probably due to methodological discrepancies. Here we investigated whether dogs follow human gaze to one of two food locations better than into distant space even after comparable pre-training. In Experiments 1 and 2, the gazing direction of dogs was recorded in a gaze-following into distant space and in an object-choice task where no choice was allowed, in order to allow a direct comparison between tasks, varying the ostensive nature of the gazes. We found that dogs only followed repeated ostensive human gaze into distant space, whereas they followed all gaze cues in the object-choice task. Dogs followed human gaze better in the object-choice task than when there was no obvious target to look at. In Experiment 3, dogs were tested in another object-choice task and were allowed to approach a container. Ostensive cues facilitated the dogs' following gaze with gaze as well as their choices: we found that dogs in the ostensive group chose the indicated container at chance level, whereas they avoided this container in the non-ostensive group. We propose that dogs may perceive the object-choice task as a competition over food and may interpret non-ostensive gaze as an intentional cue that indicates the experimenter's interest in the food location she has looked at. Whether ostensive cues simply mitigate the competitive perception of this situation or they alter how dogs interpret communicative gaze needs further investigation. Our findings also show that following gaze with one's gaze and actually choosing one of the two containers in an object-choice task need to be considered as different variables. The present study clarifies a number of questions related to gaze-following in dogs and adds to a growing body of evidence showing that human ostensive cues can strongly modify dog behaviour.

Relationship between Adolescent Risk Preferences on a Laboratory Task and Behavioral Measures of Risk-taking

PubMed Central

Rao, Uma; Sidhartha, Tanuj; Harker, Karen R.; Bidesi, Anup S.; Chen, Li-Ann; Ernst, Monique

2010-01-01

Purpose The goal of the study was to assess individual differences in risk-taking behavior among adolescents in the laboratory. A second aim was to evaluate whether the laboratory-based risk-taking behavior is associated with other behavioral and psychological measures associated with risk-taking behavior. Methods Eighty-two adolescents with no personal history of psychiatric disorder completed a computerized decision-making task, the Wheel of Fortune (WOF). By offering choices between clearly defined probabilities and real monetary outcomes, this task assesses risk preferences when participants are confronted with potential rewards and losses. The participants also completed a variety of behavioral and psychological measures associated with risk-taking behavior. Results Performance on the task varied based on the probability and anticipated outcomes. In the winning sub-task, participants selected low probability-high magnitude reward (high-risk choice) less frequently than high probability-low magnitude reward (low-risk choice). In the losing sub-task, participants selected low probability-high magnitude loss more often than high probability-low magnitude loss. On average, the selection of probabilistic rewards was optimal and similar to performance in adults. There were, however, individual differences in performance, and one-third of the adolescents made high-risk choice more frequently than low-risk choice while selecting a reward. After controlling for sociodemographic and psychological variables, high-risk choice on the winning task predicted “real-world” risk-taking behavior and substance-related problems. Conclusions These findings highlight individual differences in risk-taking behavior. Preliminary data on face validity of the WOF task suggest that it might be a valuable laboratory tool for studying behavioral and neurobiological processes associated with risk-taking behavior in adolescents. PMID:21257113

Distinguishing bias from sensitivity effects in multialternative detection tasks.

PubMed

Sridharan, Devarajan; Steinmetz, Nicholas A; Moore, Tirin; Knudsen, Eric I

2014-08-21

Studies investigating the neural bases of cognitive phenomena increasingly employ multialternative detection tasks that seek to measure the ability to detect a target stimulus or changes in some target feature (e.g., orientation or direction of motion) that could occur at one of many locations. In such tasks, it is essential to distinguish the behavioral and neural correlates of enhanced perceptual sensitivity from those of increased bias for a particular location or choice (choice bias). However, making such a distinction is not possible with established approaches. We present a new signal detection model that decouples the behavioral effects of choice bias from those of perceptual sensitivity in multialternative (change) detection tasks. By formulating the perceptual decision in a multidimensional decision space, our model quantifies the respective contributions of bias and sensitivity to multialternative behavioral choices. With a combination of analytical and numerical approaches, we demonstrate an optimal, one-to-one mapping between model parameters and choice probabilities even for tasks involving arbitrarily large numbers of alternatives. We validated the model with published data from two ternary choice experiments: a target-detection experiment and a length-discrimination experiment. The results of this validation provided novel insights into perceptual processes (sensory noise and competitive interactions) that can accurately and parsimoniously account for observers' behavior in each task. The model will find important application in identifying and interpreting the effects of behavioral manipulations (e.g., cueing attention) or neural perturbations (e.g., stimulation or inactivation) in a variety of multialternative tasks of perception, attention, and decision-making. © 2014 ARVO.

Distinguishing bias from sensitivity effects in multialternative detection tasks

PubMed Central

Sridharan, Devarajan; Steinmetz, Nicholas A.; Moore, Tirin; Knudsen, Eric I.

2014-01-01

Studies investigating the neural bases of cognitive phenomena increasingly employ multialternative detection tasks that seek to measure the ability to detect a target stimulus or changes in some target feature (e.g., orientation or direction of motion) that could occur at one of many locations. In such tasks, it is essential to distinguish the behavioral and neural correlates of enhanced perceptual sensitivity from those of increased bias for a particular location or choice (choice bias). However, making such a distinction is not possible with established approaches. We present a new signal detection model that decouples the behavioral effects of choice bias from those of perceptual sensitivity in multialternative (change) detection tasks. By formulating the perceptual decision in a multidimensional decision space, our model quantifies the respective contributions of bias and sensitivity to multialternative behavioral choices. With a combination of analytical and numerical approaches, we demonstrate an optimal, one-to-one mapping between model parameters and choice probabilities even for tasks involving arbitrarily large numbers of alternatives. We validated the model with published data from two ternary choice experiments: a target-detection experiment and a length-discrimination experiment. The results of this validation provided novel insights into perceptual processes (sensory noise and competitive interactions) that can accurately and parsimoniously account for observers' behavior in each task. The model will find important application in identifying and interpreting the effects of behavioral manipulations (e.g., cueing attention) or neural perturbations (e.g., stimulation or inactivation) in a variety of multialternative tasks of perception, attention, and decision-making. PMID:25146574

Assessment of various supervised learning algorithms using different performance metrics

NASA Astrophysics Data System (ADS)

Susheel Kumar, S. M.; Laxkar, Deepak; Adhikari, Sourav; Vijayarajan, V.

2017-11-01

Our work brings out comparison based on the performance of supervised machine learning algorithms on a binary classification task. The supervised machine learning algorithms which are taken into consideration in the following work are namely Support Vector Machine(SVM), Decision Tree(DT), K Nearest Neighbour (KNN), Naïve Bayes(NB) and Random Forest(RF). This paper mostly focuses on comparing the performance of above mentioned algorithms on one binary classification task by analysing the Metrics such as Accuracy, F-Measure, G-Measure, Precision, Misclassification Rate, False Positive Rate, True Positive Rate, Specificity, Prevalence.

Don't bet on it! Wagering as a measure of awareness in decision making under uncertainty.

PubMed

Konstantinidis, Emmanouil; Shanks, David R

2014-12-01

Can our decisions be guided by unconscious or implicit influences? According to the somatic marker hypothesis, emotion-based signals can guide our decisions in uncertain environments outside awareness. Postdecision wagering, in which participants make wagers on the outcomes of their decisions, has been recently proposed as an objective and sensitive measure of conscious content. In 5 experiments we employed variations of a classic decision-making assessment, the Iowa Gambling Task, in combination with wagering in order to investigate the role played by unconscious influences. We examined the validity of postdecision wagering by comparing it with alternative measures of conscious knowledge, specifically confidence ratings and quantitative questions. Consistent with a putative role for unconscious influences, in Experiments 2 and 3 we observed a lag between choice accuracy and the onset of advantageous wagering. However, the lag was eliminated by a change in the wagering payoff matrix (Experiment 2) and by a switch from a binary wager response to either a binary or a 4-point confidence response (Experiment 3), and wagering underestimated awareness compared to explicit quantitative questions (Experiments 1 and 4). Our results demonstrate the insensitivity of postdecision wagering as a direct measure of conscious knowledge and challenge the claim that implicit processes influence decision making under uncertainty. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Dopamine D3 Receptors Modulate the Ability of Win-Paired Cues to Increase Risky Choice in a Rat Gambling Task.

PubMed

Barrus, Michael M; Winstanley, Catharine A

2016-01-20

Similar to other addiction disorders, the cues inherent in many gambling procedures are thought to play an important role in mediating their addictive nature. Animal models of gambling-related behavior, while capturing dimensions of economic decision making, have yet to address the impact that these salient cues may have in promoting maladaptive choice. Here, we determined whether adding win-associated audiovisual cues to a rat gambling task (rGT) would influence decision making. Thirty-two male Long-Evans rats were tested on either the cued or uncued rGT. In these tasks, animals chose between four options associated with different magnitudes and frequencies of reward and punishing time-out periods. As in the Iowa Gambling Task, favoring options associated with smaller per-trial rewards but smaller losses and avoiding the tempting "high-risk, high-reward" decks maximized profits. Although the reinforcement contingencies were identical in both task versions, rats' choice of the disadvantageous risky options was significantly greater on the cued task. Furthermore, a D3 receptor agonist increased choice of the disadvantageous options, whereas a D3 antagonist had the opposite effects, only on the cued task. These findings are consistent with the reported role of D3 receptors in mediating the facilitatory effects of cues in addiction. Collectively, these results indicate that the cued rGT is a valuable model with which to study the mechanism by which salient cues can invigorate maladaptive decision making, an important and understudied component of both gambling and substance use disorders. Significance statement: We used a rodent analog of the Iowa Gambling Task to determine whether the addition of audiovisual cues would affect choice preferences. Adding reward-concurrent cues significantly increased risky choice. This is the first clear demonstration that reward-paired cues can bias cost/benefit decision making against a subject's best interests in a manner concordant with elevated addiction susceptibility. Choice on the cued task was uniquely sensitive to modulation by D3 receptor ligands, yet these drugs did not alter decision making on the uncued task. The relatively unprecedented sensitivity of choice on the cued task to D3-receptor-mediated neurotransmission data suggest that similar neurobiological processes underlie the ability of cues to both bias animals toward risky options and facilitate drug addiction. Copyright © 2016 the authors 0270-6474/16/360785-10$15.00/0.

Autonomous self-configuration of artificial neural networks for data classification or system control

NASA Astrophysics Data System (ADS)

Fink, Wolfgang

2009-05-01

Artificial neural networks (ANNs) are powerful methods for the classification of multi-dimensional data as well as for the control of dynamic systems. In general terms, ANNs consist of neurons that are, e.g., arranged in layers and interconnected by real-valued or binary neural couplings or weights. ANNs try mimicking the processing taking place in biological brains. The classification and generalization capabilities of ANNs are given by the interconnection architecture and the coupling strengths. To perform a certain classification or control task with a particular ANN architecture (i.e., number of neurons, number of layers, etc.), the inter-neuron couplings and their accordant coupling strengths must be determined (1) either by a priori design (i.e., manually) or (2) using training algorithms such as error back-propagation. The more complex the classification or control task, the less obvious it is how to determine an a priori design of an ANN, and, as a consequence, the architecture choice becomes somewhat arbitrary. Furthermore, rather than being able to determine for a given architecture directly the corresponding coupling strengths necessary to perform the classification or control task, these have to be obtained/learned through training of the ANN on test data. We report on the use of a Stochastic Optimization Framework (SOF; Fink, SPIE 2008) for the autonomous self-configuration of Artificial Neural Networks (i.e., the determination of number of hidden layers, number of neurons per hidden layer, interconnections between neurons, and respective coupling strengths) for performing classification or control tasks. This may provide an approach towards cognizant and self-adapting computing architectures and systems.

Visual search in a forced-choice paradigm

NASA Technical Reports Server (NTRS)

Holmgren, J. E.

1974-01-01

The processing of visual information was investigated in the context of two visual search tasks. The first was a forced-choice task in which one of two alternative letters appeared in a visual display of from one to five letters. The second task included trials on which neither of the two alternatives was present in the display. Search rates were estimated from the slopes of best linear fits to response latencies plotted as a function of the number of items in the visual display. These rates were found to be much slower than those estimated in yes-no search tasks. This result was interpreted as indicating that the processes underlying visual search in yes-no and forced-choice tasks are not the same.

Factors Predicting Smoking in a Laboratory-Based Smoking-Choice Task

PubMed Central

Bold, Krysten W.; Yoon, Haewon; Chapman, Gretchen B.; McCarthy, Danielle E.

2013-01-01

This study aimed to expand the current understanding of smoking maintenance mechanisms by examining how putative relapse risk factors relate to a single behavioral smoking choice using a novel laboratory smoking-choice task. After 12 hours of nicotine deprivation, participants were exposed to smoking cues and given the choice between smoking up to two cigarettes in a 15-minute window or waiting and receiving four cigarettes after a delay of 45 minutes. Greater nicotine dependence, higher impulsivity, and lower distress tolerance were hypothesized to predict earlier and more intensive smoking. Out of 35 participants (n=9 female), 26 chose to smoke with a median time to a first puff of 1.22 minutes (standard deviation=2.62 min, range=0.03–10.62 min). Survival analyses examined latency to first puff, and results indicated that greater pre-task craving and smoking more cigarettes per day were significantly related to smoking sooner in the task. Greater behavioral disinhibition predicted shorter smoking latency in the first two minutes of the task, but not at a delay of more than two minutes. Lower distress tolerance (reporting greater regulation efforts to alleviate distress) was related to more puffs smoked and greater nicotine dependence was related to more time spent smoking in the task. This novel laboratory smoking-choice paradigm may be a useful laboratory analog for the choices smokers make during cessation attempts and may help identify factors that influence smoking lapses. PMID:23421357

Effort in Multitasking: Local and Global Assessment of Effort.

PubMed

Kiesel, Andrea; Dignath, David

2017-01-01

When performing multiple tasks in succession, self-organization of task order might be superior compared to external-controlled task schedules, because self-organization allows optimizing processing modes and thus reduces switch costs, and it increases commitment to task goals. However, self-organization is an additional executive control process that is not required if task order is externally specified and as such it is considered as time-consuming and effortful. To compare self-organized and externally controlled task scheduling, we suggest assessing global subjective and objectives measures of effort in addition to local performance measures. In our new experimental approach, we combined characteristics of dual tasking settings and task switching settings and compared local and global measures of effort in a condition with free choice of task sequence and a condition with cued task sequence. In a multi-tasking environment, participants chose the task order while the task requirement of the not-yet-performed task remained the same. This task preview allowed participants to work on the previously non-chosen items in parallel and resulted in faster responses and fewer errors in task switch trials than in task repetition trials. The free-choice group profited more from this task preview than the cued group when considering local performance measures. Nevertheless, the free-choice group invested more effort than the cued group when considering global measures. Thus, self-organization in task scheduling seems to be effortful even in conditions in which it is beneficiary for task processing. In a second experiment, we reduced the possibility of task preview for the not-yet-performed tasks in order to hinder efficient self-organization. Here neither local nor global measures revealed substantial differences between the free-choice and a cued task sequence condition. Based on the results of both experiments, we suggest that global assessment of effort in addition to local performance measures might be a useful tool for multitasking research.

There Are at Least Two Kinds of Probability Matching: Evidence from a Secondary Task

ERIC Educational Resources Information Center

Otto, A. Ross; Taylor, Eric G.; Markman, Arthur B.

2011-01-01

Probability matching is a suboptimal behavior that often plagues human decision-making in simple repeated choice tasks. Despite decades of research, recent studies cannot find agreement on what choice strategies lead to probability matching. We propose a solution, showing that two distinct local choice strategies--which make different demands on…

The Relation between Metastrategic Knowledge, Strategy Use and Task Performance: Findings and Reflections from a Numerosity Judgement Task

ERIC Educational Resources Information Center

Luwel, Koen; Torbeyns, Joke; Verschaffel, Lieven

2003-01-01

In the research literature several positions concerning the role played by metacognition in adaptive strategy choice can be distinguished. While many authors adhere so-called metacognitive models of strategy choice and strategy change, others have questioned the extent to which metacognitive factors are associated with strategy choice and task…

The Impact of Learner Attributes and Learner Choice in an Agent-Based Environment

ERIC Educational Resources Information Center

Kim, Yanghee; Wei, Quan

2011-01-01

This study examined the impact of learners' attributes (gender and ethnicity) on their choice of a pedagogical agent and the impact of the attributes and choice on their perceptions of agent affability, task-specific attitudes, task-specific self-efficacy, and learning gains. Participants were 210 high-school male and female, Caucasian and…

Children's Choice Strategies: The Effects of Age and Task Demands

ERIC Educational Resources Information Center

Bereby-Meyer, Yoella; Assor, Avi; Katz, Idit

2004-01-01

Two experiments examined the effect of age and cognitive demands on children's choice strategies. Children aged 8-9 and 12-13 years were asked to choose among either two or four products that differed in several attributes of varying importance to them. Choice tasks were designed to differentiate between the lexicographic and the equal-weighting…

Piéron’s Law and Optimal Behavior in Perceptual Decision-Making

PubMed Central

van Maanen, Leendert; Grasman, Raoul P. P. P.; Forstmann, Birte U.; Wagenmakers, Eric-Jan

2012-01-01

Piéron’s Law is a psychophysical regularity in signal detection tasks that states that mean response times decrease as a power function of stimulus intensity. In this article, we extend Piéron’s Law to perceptual two-choice decision-making tasks, and demonstrate that the law holds as the discriminability between two competing choices is manipulated, even though the stimulus intensity remains constant. This result is consistent with predictions from a Bayesian ideal observer model. The model assumes that in order to respond optimally in a two-choice decision-making task, participants continually update the posterior probability of each response alternative, until the probability of one alternative crosses a criterion value. In addition to predictions for two-choice decision-making tasks, we extend the ideal observer model to predict Piéron’s Law in signal detection tasks. We conclude that Piéron’s Law is a general phenomenon that may be caused by optimality constraints. PMID:22232572

Task Switching and Shifting between Stopping and Going: Developmental Change in between-Trial Control Adjustments

ERIC Educational Resources Information Center

Huizing, Mariette; van der Molen, Maurits W.

2011-01-01

This study set out to investigate developmental differences in the ability to switch between choice tasks and to shift between Go/NoGo and choice tasks. Three age groups (7-year-olds, 11-year-olds, and young adults) were asked to consider the shape or color of a bivalued target stimulus. The participants performed a switch task in which a cue…

The Effect of Including an Opt-Out Option in Discrete Choice Experiments

PubMed Central

Veldwijk, Jorien; Lambooij, Mattijs S.; de Bekker-Grob, Esther W.; Smit, Henriëtte A.; de Wit, G. Ardine

2014-01-01

Objective to determine to what extent the inclusion of an opt-out option in a DCE may have an effect on choice behaviour and therefore might influence the attribute level estimates, the relative importance of the attributes and calculated trade-offs. Methods 781 Dutch Type 2 Diabetes Mellitus patients completed a questionnaire containing nine choice tasks with an opt-out option and nice forced choice tasks. Mixed-logit models were used to estimate the relative importance of the five lifestyle program related attributes that were included. Willingness to pay (WTP) values were calculated and it was tested whether results differed between respondents who answered the choice tasks with an opt-out option in the first or second part of the questionnaire. Results 21.4% of the respondents always opted out. Respondents who were given the opt-out option in the first part of the questionnaire as well as lower educated respondents significantly more often opted out. For both the forced and unforced choice model, different attributes showed significant estimates, the relative importance of the attributes was equal. However, due to differences in relative importance weights, the WTP values for the PA schedule differed significantly between both datasets. Conclusions Results show differences in opting out based on the location of the opt-out option and respondents' educational level; this resulted in small differences between the forced and unforced choice model. Since respondents seem to learn from answering forced choice tasks, a dual response design might result in higher data quality compared to offering a direct opt-out option. Future research should empirically explore how choice sets should be presented to make them as easy and less complex as possible in order to reduce the proportion of respondents that opts-out due to choice task complexity. Moreover, future research should debrief respondents to examine the reasons for choosing the opt-out alternative. PMID:25365169

The effect of including an opt-out option in discrete choice experiments.

PubMed

Veldwijk, Jorien; Lambooij, Mattijs S; de Bekker-Grob, Esther W; Smit, Henriëtte A; de Wit, G Ardine

2014-01-01

to determine to what extent the inclusion of an opt-out option in a DCE may have an effect on choice behaviour and therefore might influence the attribute level estimates, the relative importance of the attributes and calculated trade-offs. 781 Dutch Type 2 Diabetes Mellitus patients completed a questionnaire containing nine choice tasks with an opt-out option and nice forced choice tasks. Mixed-logit models were used to estimate the relative importance of the five lifestyle program related attributes that were included. Willingness to pay (WTP) values were calculated and it was tested whether results differed between respondents who answered the choice tasks with an opt-out option in the first or second part of the questionnaire. 21.4% of the respondents always opted out. Respondents who were given the opt-out option in the first part of the questionnaire as well as lower educated respondents significantly more often opted out. For both the forced and unforced choice model, different attributes showed significant estimates, the relative importance of the attributes was equal. However, due to differences in relative importance weights, the WTP values for the PA schedule differed significantly between both datasets. Results show differences in opting out based on the location of the opt-out option and respondents' educational level; this resulted in small differences between the forced and unforced choice model. Since respondents seem to learn from answering forced choice tasks, a dual response design might result in higher data quality compared to offering a direct opt-out option. Future research should empirically explore how choice sets should be presented to make them as easy and less complex as possible in order to reduce the proportion of respondents that opts-out due to choice task complexity. Moreover, future research should debrief respondents to examine the reasons for choosing the opt-out alternative.

Using Statechart Assertion for the Formal Validation and Verification of a Real-Time Software System: A Case Study

DTIC Science & Technology

2011-03-01

could be an entry point into a repeated task (or thread). The following example uses binary semaphores . The VxWorks operating system utilizes binary... semaphores via system calls: SemTake and SemGive. These semaphores are used primarily for mutual exclusion to protect resources from being accessed

Least Squares Distance Method of Cognitive Validation and Analysis for Binary Items Using Their Item Response Theory Parameters

ERIC Educational Resources Information Center

Dimitrov, Dimiter M.

2007-01-01

The validation of cognitive attributes required for correct answers on binary test items or tasks has been addressed in previous research through the integration of cognitive psychology and psychometric models using parametric or nonparametric item response theory, latent class modeling, and Bayesian modeling. All previous models, each with their…

Minimizing effects of methodological decisions on interpretation and prediction in species distribution studies: An example with background selection

USGS Publications Warehouse

Jarnevich, Catherine S.; Talbert, Marian; Morisette, Jeffrey T.; Aldridge, Cameron L.; Brown, Cynthia; Kumar, Sunil; Manier, Daniel; Talbert, Colin; Holcombe, Tracy R.

2017-01-01

Evaluating the conditions where a species can persist is an important question in ecology both to understand tolerances of organisms and to predict distributions across landscapes. Presence data combined with background or pseudo-absence locations are commonly used with species distribution modeling to develop these relationships. However, there is not a standard method to generate background or pseudo-absence locations, and method choice affects model outcomes. We evaluated combinations of both model algorithms (simple and complex generalized linear models, multivariate adaptive regression splines, Maxent, boosted regression trees, and random forest) and background methods (random, minimum convex polygon, and continuous and binary kernel density estimator (KDE)) to assess the sensitivity of model outcomes to choices made. We evaluated six questions related to model results, including five beyond the common comparison of model accuracy assessment metrics (biological interpretability of response curves, cross-validation robustness, independent data accuracy and robustness, and prediction consistency). For our case study with cheatgrass in the western US, random forest was least sensitive to background choice and the binary KDE method was least sensitive to model algorithm choice. While this outcome may not hold for other locations or species, the methods we used can be implemented to help determine appropriate methodologies for particular research questions.

Do pet dogs (Canis familiaris) follow ostensive and non-ostensive human gaze to distant space and to objects?

PubMed Central

Range, Friederike; Virányi, Zsófia

2017-01-01

Dogs are renowned for being skilful at using human-given communicative cues such as pointing. Results are contradictory, however, when it comes to dogs' following human gaze, probably due to methodological discrepancies. Here we investigated whether dogs follow human gaze to one of two food locations better than into distant space even after comparable pre-training. In Experiments 1 and 2, the gazing direction of dogs was recorded in a gaze-following into distant space and in an object-choice task where no choice was allowed, in order to allow a direct comparison between tasks, varying the ostensive nature of the gazes. We found that dogs only followed repeated ostensive human gaze into distant space, whereas they followed all gaze cues in the object-choice task. Dogs followed human gaze better in the object-choice task than when there was no obvious target to look at. In Experiment 3, dogs were tested in another object-choice task and were allowed to approach a container. Ostensive cues facilitated the dogs’ following gaze with gaze as well as their choices: we found that dogs in the ostensive group chose the indicated container at chance level, whereas they avoided this container in the non-ostensive group. We propose that dogs may perceive the object-choice task as a competition over food and may interpret non-ostensive gaze as an intentional cue that indicates the experimenter's interest in the food location she has looked at. Whether ostensive cues simply mitigate the competitive perception of this situation or they alter how dogs interpret communicative gaze needs further investigation. Our findings also show that following gaze with one's gaze and actually choosing one of the two containers in an object-choice task need to be considered as different variables. The present study clarifies a number of questions related to gaze-following in dogs and adds to a growing body of evidence showing that human ostensive cues can strongly modify dog behaviour. PMID:28791164

How self-determined choice facilitates performance: a key role of the ventromedial prefrontal cortex.

PubMed

Murayama, Kou; Matsumoto, Madoka; Izuma, Keise; Sugiura, Ayaka; Ryan, Richard M; Deci, Edward L; Matsumoto, Kenji

2015-05-01

Recent studies have documented that self-determined choice does indeed enhance performance. However, the precise neural mechanisms underlying this effect are not well understood. We examined the neural correlates of the facilitative effects of self-determined choice using functional magnetic resonance imaging (fMRI). Participants played a game-like task involving a stopwatch with either a stopwatch they selected (self-determined-choice condition) or one they were assigned without choice (forced-choice condition). Our results showed that self-determined choice enhanced performance on the stopwatch task, despite the fact that the choices were clearly irrelevant to task difficulty. Neuroimaging results showed that failure feedback, compared with success feedback, elicited a drop in the vmPFC activation in the forced-choice condition, but not in the self-determined-choice condition, indicating that negative reward value associated with the failure feedback vanished in the self-determined-choice condition. Moreover, the vmPFC resilience to failure in the self-determined-choice condition was significantly correlated with the increased performance. Striatal responses to failure and success feedback were not modulated by the choice condition, indicating the dissociation between the vmPFC and striatal activation pattern. These findings suggest that the vmPFC plays a unique and critical role in the facilitative effects of self-determined choice on performance. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Affective biasing of choices in gambling task decision making.

PubMed

Hinson, John M; Whitney, Paul; Holben, Heather; Wirick, Aaron K

2006-09-01

The proponents of the somatic marker hypothesis presume that rational decision making is guided by emotional reactions that are developed from prior experience. Supporting evidence for the hypothesis comes almost exclusively from the short-term affective reactions that are learned during the course of a hypothetical decision-making task--the gambling task (GT). We examined GT performance and affective reactions to choices when those choices were biased by words that had preexisting affective value. In one experiment, affectively valued words directly signaled good and bad choices. A congruent relation between affective value of word and choice outcome improved GT performance, whereas an incongruent relation greatly interfered with performance. In another experiment, affectively valued words were maintained as a working memory (WM) load between GT choices. A WM load with affectively positive words somewhat improved GT performance, whereas affectively negative words interfered with performance. Somatic markers-indicated by differential anticipatory skin conductance response (SCR) amplitude for good and bad choices-appeared at a point in the GT session when choice performance was superior. However, differential SCR developed during the session after good choice performance was already established. These results indicate that preexisting affective biases can influence GT decision making. In addition, the somatic markers that are regular accompaniments of GT decision making appeared to be temporally lagging indicators of choice performance.

Measuring pilot workload in a moving-base simulator. I Asynchronous secondary choice-reaction task

NASA Technical Reports Server (NTRS)

Kantowitz, B. H.; Hart, S. G.; Bortolussi, M. R.

1983-01-01

The de facto method for measuring airplane pilot workload is based upon subjective ratings. While researchers agree that such subjective data should be bolstered by using objective behavioral measures, results to date have been mixed. No clear objective technique has surfaced as the metric of choice. It is believed that this difficulty is in part due to neglect of theoretical work in psychology that predicts some of the difficulties that are inherent in a futile search for 'the one and only' best secondary task to measure workload. An initial study that used both subjective ratings and an asynchronous choice-reaction secondary task was conducted to determine if such a secondary task could indeed meet the methodological constraints imposed by current theories of attention. Two variants of a flight scenario were combined with two levels of the secondary task. Appropriate single-task control conditions were also included. Results give grounds for cautious optimism but indicate that future research should use synchronous secondary tasks where possible.

Accuracy of Binary Black Hole Waveform Models for Advanced LIGO

NASA Astrophysics Data System (ADS)

Kumar, Prayush; Fong, Heather; Barkett, Kevin; Bhagwat, Swetha; Afshari, Nousha; Chu, Tony; Brown, Duncan; Lovelace, Geoffrey; Pfeiffer, Harald; Scheel, Mark; Szilagyi, Bela; Simulating Extreme Spacetimes (SXS) Team

2016-03-01

Coalescing binaries of compact objects, such as black holes and neutron stars, are the primary targets for gravitational-wave (GW) detection with Advanced LIGO. Accurate modeling of the emitted GWs is required to extract information about the binary source. The most accurate solution to the general relativistic two-body problem is available in numerical relativity (NR), which is however limited in application due to computational cost. Current searches use semi-analytic models that are based in post-Newtonian (PN) theory and calibrated to NR. In this talk, I will present comparisons between contemporary models and high-accuracy numerical simulations performed using the Spectral Einstein Code (SpEC), focusing at the questions: (i) How well do models capture binary's late-inspiral where they lack a-priori accurate information from PN or NR, and (ii) How accurately do they model binaries with parameters outside their range of calibration. These results guide the choice of templates for future GW searches, and motivate future modeling efforts.

Modeling the Value of Strategic Actions in the Superior Colliculus

PubMed Central

Thevarajah, Dhushan; Webb, Ryan; Ferrall, Christopher; Dorris, Michael C.

2009-01-01

In learning models of strategic game play, an agent constructs a valuation (action value) over possible future choices as a function of past actions and rewards. Choices are then stochastic functions of these action values. Our goal is to uncover a neural signal that correlates with the action value posited by behavioral learning models. We measured activity from neurons in the superior colliculus (SC), a midbrain region involved in planning saccadic eye movements, while monkeys performed two saccade tasks. In the strategic task, monkeys competed against a computer in a saccade version of the mixed-strategy game ”matching-pennies”. In the instructed task, saccades were elicited through explicit instruction rather than free choices. In both tasks neuronal activity and behavior were shaped by past actions and rewards with more recent events exerting a larger influence. Further, SC activity predicted upcoming choices during the strategic task and upcoming reaction times during the instructed task. Finally, we found that neuronal activity in both tasks correlated with an established learning model, the Experience Weighted Attraction model of action valuation (Camerer and Ho, 1999). Collectively, our results provide evidence that action values hypothesized by learning models are represented in the motor planning regions of the brain in a manner that could be used to select strategic actions. PMID:20161807

Social Influences on Creativity: Interactive Effects of Reward and Choice.

ERIC Educational Resources Information Center

Amabile, Teresa M.

In a test of intrinsic motivation hypothesis of creativity, 60 undergraduate women did an artistic creativity task with either the expectation of receiving a reward or no expectation of reward. Reward was crossed with choice in task engagement, such that half of the reward Ss contracted to do the task in order to receive reward, and half simply…

Why Face a Challenge? The Reason behind Intrinsically Motivated Students' Spontaneous Choice of Challenging Tasks

ERIC Educational Resources Information Center

Inoue, Noriyuki

2007-01-01

In a task choice situation, why do some students spontaneously choose challenging tasks while others do not? In the study, 114 undergraduate students were first asked of their perceived competence and interest in solving number puzzles at both individual and situational levels, and then asked to choose one puzzle from four difficulty levels. They…

Simulation study to determine the impact of different design features on design efficiency in discrete choice experiments

PubMed Central

Vanniyasingam, Thuva; Cunningham, Charles E; Foster, Gary; Thabane, Lehana

2016-01-01

Objectives Discrete choice experiments (DCEs) are routinely used to elicit patient preferences to improve health outcomes and healthcare services. While many fractional factorial designs can be created, some are more statistically optimal than others. The objective of this simulation study was to investigate how varying the number of (1) attributes, (2) levels within attributes, (3) alternatives and (4) choice tasks per survey will improve or compromise the statistical efficiency of an experimental design. Design and methods A total of 3204 DCE designs were created to assess how relative design efficiency (d-efficiency) is influenced by varying the number of choice tasks (2–20), alternatives (2–5), attributes (2–20) and attribute levels (2–5) of a design. Choice tasks were created by randomly allocating attribute and attribute level combinations into alternatives. Outcome Relative d-efficiency was used to measure the optimality of each DCE design. Results DCE design complexity influenced statistical efficiency. Across all designs, relative d-efficiency decreased as the number of attributes and attribute levels increased. It increased for designs with more alternatives. Lastly, relative d-efficiency converges as the number of choice tasks increases, where convergence may not be at 100% statistical optimality. Conclusions Achieving 100% d-efficiency is heavily dependent on the number of attributes, attribute levels, choice tasks and alternatives. Further exploration of overlaps and block sizes are needed. This study's results are widely applicable for researchers interested in creating optimal DCE designs to elicit individual preferences on health services, programmes, policies and products. PMID:27436671

Treatment Effect Estimation Using Nonlinear Two-Stage Instrumental Variable Estimators: Another Cautionary Note.

PubMed

Chapman, Cole G; Brooks, John M

2016-12-01

To examine the settings of simulation evidence supporting use of nonlinear two-stage residual inclusion (2SRI) instrumental variable (IV) methods for estimating average treatment effects (ATE) using observational data and investigate potential bias of 2SRI across alternative scenarios of essential heterogeneity and uniqueness of marginal patients. Potential bias of linear and nonlinear IV methods for ATE and local average treatment effects (LATE) is assessed using simulation models with a binary outcome and binary endogenous treatment across settings varying by the relationship between treatment effectiveness and treatment choice. Results show that nonlinear 2SRI models produce estimates of ATE and LATE that are substantially biased when the relationships between treatment and outcome for marginal patients are unique from relationships for the full population. Bias of linear IV estimates for LATE was low across all scenarios. Researchers are increasingly opting for nonlinear 2SRI to estimate treatment effects in models with binary and otherwise inherently nonlinear dependent variables, believing that it produces generally unbiased and consistent estimates. This research shows that positive properties of nonlinear 2SRI rely on assumptions about the relationships between treatment effect heterogeneity and choice. © Health Research and Educational Trust.

SNPassoc: an R package to perform whole genome association studies.

PubMed

González, Juan R; Armengol, Lluís; Solé, Xavier; Guinó, Elisabet; Mercader, Josep M; Estivill, Xavier; Moreno, Víctor

2007-03-01

The popularization of large-scale genotyping projects has led to the widespread adoption of genetic association studies as the tool of choice in the search for single nucleotide polymorphisms (SNPs) underlying susceptibility to complex diseases. Although the analysis of individual SNPs is a relatively trivial task, when the number is large and multiple genetic models need to be explored it becomes necessary a tool to automate the analyses. In order to address this issue, we developed SNPassoc, an R package to carry out most common analyses in whole genome association studies. These analyses include descriptive statistics and exploratory analysis of missing values, calculation of Hardy-Weinberg equilibrium, analysis of association based on generalized linear models (either for quantitative or binary traits), and analysis of multiple SNPs (haplotype and epistasis analysis). Package SNPassoc is available at CRAN from http://cran.r-project.org. A tutorial is available on Bioinformatics online and in http://davinci.crg.es/estivill_lab/snpassoc.

Effect of feedback mode and task difficulty on quality of timing decisions in a zero-sum game.

PubMed

Tikuisis, Peter; Vartanian, Oshin; Mandel, David R

2014-09-01

The objective was to investigate the interaction between the mode of performance outcome feedback and task difficulty on timing decisions (i.e., when to act). Feedback is widely acknowledged to affect task performance. However, the extent to which feedback display mode and its impact on timing decisions is moderated by task difficulty remains largely unknown. Participants repeatedly engaged a zero-sum game involving silent duels with a computerized opponent and were given visual performance feedback after each engagement. They were sequentially tested on three different levels of task difficulty (low, intermediate, and high) in counterbalanced order. Half received relatively simple "inside view" binary outcome feedback, and the other half received complex "outside view" hit rate probability feedback. The key dependent variables were response time (i.e., time taken to make a decision) and survival outcome. When task difficulty was low to moderate, participants were more likely to learn and perform better from hit rate probability feedback than binary outcome feedback. However, better performance with hit rate feedback exacted a higher cognitive cost manifested by higher decision response time. The beneficial effect of hit rate probability feedback on timing decisions is partially moderated by task difficulty. Performance feedback mode should be judiciously chosen in relation to task difficulty for optimal performance in tasks involving timing decisions.

The Characteristics of Binary Spike-Time-Dependent Plasticity in HfO2-Based RRAM and Applications for Pattern Recognition

NASA Astrophysics Data System (ADS)

Zhou, Zheng; Liu, Chen; Shen, Wensheng; Dong, Zhen; Chen, Zhe; Huang, Peng; Liu, Lifeng; Liu, Xiaoyan; Kang, Jinfeng

2017-04-01

A binary spike-time-dependent plasticity (STDP) protocol based on one resistive-switching random access memory (RRAM) device was proposed and experimentally demonstrated in the fabricated RRAM array. Based on the STDP protocol, a novel unsupervised online pattern recognition system including RRAM synapses and CMOS neurons is developed. Our simulations show that the system can efficiently compete the handwritten digits recognition task, which indicates the feasibility of using the RRAM-based binary STDP protocol in neuromorphic computing systems to obtain good performance.

Brain correlates of subjective freedom of choice.

PubMed

Filevich, Elisa; Vanneste, Patricia; Brass, Marcel; Fias, Wim; Haggard, Patrick; Kühn, Simone

2013-12-01

The subjective feeling of free choice is an important feature of human experience. Experimental tasks have typically studied free choice by contrasting free and instructed selection of response alternatives. These tasks have been criticised, and it remains unclear how they relate to the subjective feeling of freely choosing. We replicated previous findings of the fMRI correlates of free choice, defined objectively. We introduced a novel task in which participants could experience and report a graded sense of free choice. BOLD responses for conditions subjectively experienced as free identified a postcentral area distinct from the areas typically considered to be involved in free action. Thus, the brain correlates of subjective feeling of free action were not directly related to any established brain correlates of objectively-defined free action. Our results call into question traditional assumptions about the relation between subjective experience of choosing and activity in the brain's so-called voluntary motor areas. Copyright © 2013. Published by Elsevier Inc.

Brain correlates of subjective freedom of choice

PubMed Central

Filevich, Elisa; Vanneste, Patricia; Brass, Marcel; Fias, Wim; Haggard, Patrick; Kühn, Simone

2013-01-01

The subjective feeling of free choice is an important feature of human experience. Experimental tasks have typically studied free choice by contrasting free and instructed selection of response alternatives. These tasks have been criticised, and it remains unclear how they relate to the subjective feeling of freely choosing. We replicated previous findings of the fMRI correlates of free choice, defined objectively. We introduced a novel task in which participants could experience and report a graded sense of free choice. BOLD responses for conditions subjectively experienced as free identified a postcentral area distinct from the areas typically considered to be involved in free action. Thus, the brain correlates of subjective feeling of free action were not directly related to any established brain correlates of objectively-defined free action. Our results call into question traditional assumptions about the relation between subjective experience of choosing and activity in the brain’s so-called voluntary motor areas. PMID:24021855

People's Financial Choice Depends on their Previous Task Success or Failure.

PubMed

Sekścińska, Katarzyna

2015-01-01

Existing knowledge about the impact of the experience prior to financial choices has been limited almost exclusively to single risky choices. Moreover, the results obtained in these studies have not been entirely consistent. For example, some studies suggested that the experience of success makes people more willing to take a risk, while other studies led to the opposite conclusions. The results of the two experimental studies presented in this paper provide evidence for the hypothesis that the experience of success or failure influences people's financial choices, but the effect of the success or failure depends on the type of task (financial and non-financial) preceding a financial decision. The experience of success in financial tasks increased participants' tendency to invest and make risky investment choices, while it also made them less prone to save. On the other hand, the experience of failure heightened the amount of money that participants decided to save, and lowered their tendency to invest and make risky investment choices. However, the effects of the experience of success or failure in non-financial tasks were exactly the opposite. The presented studies indicated the role of the specific circumstances in which the individual gains the experience as a possible way to explain the discrepancies in the results of studies on the relationship between the experience prior to financial choice with a tendency to take risks.

People’s Financial Choice Depends on their Previous Task Success or Failure

PubMed Central

Sekścińska, Katarzyna

2015-01-01

Existing knowledge about the impact of the experience prior to financial choices has been limited almost exclusively to single risky choices. Moreover, the results obtained in these studies have not been entirely consistent. For example, some studies suggested that the experience of success makes people more willing to take a risk, while other studies led to the opposite conclusions. The results of the two experimental studies presented in this paper provide evidence for the hypothesis that the experience of success or failure influences people’s financial choices, but the effect of the success or failure depends on the type of task (financial and non-financial) preceding a financial decision. The experience of success in financial tasks increased participants’ tendency to invest and make risky investment choices, while it also made them less prone to save. On the other hand, the experience of failure heightened the amount of money that participants decided to save, and lowered their tendency to invest and make risky investment choices. However, the effects of the experience of success or failure in non-financial tasks were exactly the opposite. The presented studies indicated the role of the specific circumstances in which the individual gains the experience as a possible way to explain the discrepancies in the results of studies on the relationship between the experience prior to financial choice with a tendency to take risks. PMID:26635654

SEXUAL SELECTION. Irrationality in mate choice revealed by túngara frogs.

PubMed

Lea, Amanda M; Ryan, Michael J

2015-08-28

Mate choice models derive from traditional microeconomic decision theory and assume that individuals maximize their Darwinian fitness by making economically rational decisions. Rational choices exhibit regularity, whereby the relative strength of preferences between options remains stable when additional options are presented. We tested female frogs with three simulated males who differed in relative call attractiveness and call rate. In binary choice tests, females' preferences favored stimulus caller B over caller A; however, with the addition of an inferior "decoy" C, females reversed their preferences and chose A over B. These results show that the relative valuation of mates is not independent of inferior alternatives in the choice set and therefore cannot be explained with the rational choice models currently used in sexual selection theory. Copyright © 2015, American Association for the Advancement of Science.

Taking the easy way out? Increasing implementation effort reduces probability maximizing under cognitive load.

PubMed

Schulze, Christin; Newell, Ben R

2016-07-01

Cognitive load has previously been found to have a positive effect on strategy selection in repeated risky choice. Specifically, whereas inferior probability matching often prevails under single-task conditions, optimal probability maximizing sometimes dominates when a concurrent task competes for cognitive resources. We examined the extent to which this seemingly beneficial effect of increased task demands hinges on the effort required to implement each of the choice strategies. Probability maximizing typically involves a simple repeated response to a single option, whereas probability matching requires choice proportions to be tracked carefully throughout a sequential choice task. Here, we flipped this pattern by introducing a manipulation that made the implementation of maximizing more taxing and, at the same time, allowed decision makers to probability match via a simple repeated response to a single option. The results from two experiments showed that increasing the implementation effort of probability maximizing resulted in decreased adoption rates of this strategy. This was the case both when decision makers simultaneously learned about the outcome probabilities and responded to a dual task (Exp. 1) and when these two aspects were procedurally separated in two distinct stages (Exp. 2). We conclude that the effort involved in implementing a choice strategy is a key factor in shaping repeated choice under uncertainty. Moreover, highlighting the importance of implementation effort casts new light on the sometimes surprising and inconsistent effects of cognitive load that have previously been reported in the literature.

Learning Rotation-Invariant Local Binary Descriptor.

PubMed

Duan, Yueqi; Lu, Jiwen; Feng, Jianjiang; Zhou, Jie

2017-08-01

In this paper, we propose a rotation-invariant local binary descriptor (RI-LBD) learning method for visual recognition. Compared with hand-crafted local binary descriptors, such as local binary pattern and its variants, which require strong prior knowledge, local binary feature learning methods are more efficient and data-adaptive. Unlike existing learning-based local binary descriptors, such as compact binary face descriptor and simultaneous local binary feature learning and encoding, which are susceptible to rotations, our RI-LBD first categorizes each local patch into a rotational binary pattern (RBP), and then jointly learns the orientation for each pattern and the projection matrix to obtain RI-LBDs. As all the rotation variants of a patch belong to the same RBP, they are rotated into the same orientation and projected into the same binary descriptor. Then, we construct a codebook by a clustering method on the learned binary codes, and obtain a histogram feature for each image as the final representation. In order to exploit higher order statistical information, we extend our RI-LBD to the triple rotation-invariant co-occurrence local binary descriptor (TRICo-LBD) learning method, which learns a triple co-occurrence binary code for each local patch. Extensive experimental results on four different visual recognition tasks, including image patch matching, texture classification, face recognition, and scene classification, show that our RI-LBD and TRICo-LBD outperform most existing local descriptors.

Instruction in information structuring improves Bayesian judgment in intelligence analysts.

PubMed

Mandel, David R

2015-01-01

An experiment was conducted to test the effectiveness of brief instruction in information structuring (i.e., representing and integrating information) for improving the coherence of probability judgments and binary choices among intelligence analysts. Forty-three analysts were presented with comparable sets of Bayesian judgment problems before and immediately after instruction. After instruction, analysts' probability judgments were more coherent (i.e., more additive and compliant with Bayes theorem). Instruction also improved the coherence of binary choices regarding category membership: after instruction, subjects were more likely to invariably choose the category to which they assigned the higher probability of a target's membership. The research provides a rare example of evidence-based validation of effectiveness in instruction to improve the statistical assessment skills of intelligence analysts. Such instruction could also be used to improve the assessment quality of other types of experts who are required to integrate statistical information or make probabilistic assessments.

Speed of Processing and Reading Disability: A Cross-Linguistic Investigation of Dyslexia and Borderline Intellectual Functioning

ERIC Educational Resources Information Center

Bonifacci, Paola; Snowling, Margaret J.

2008-01-01

English and Italian children with dyslexia were compared with children with reading difficulties associated with low-IQ on tests of simple and choice RT, and in number and symbol scanning tasks. On all four speed-of-processing tasks, children with low-IQ responded more slowly than children with dyslexia and age-controls. In the choice RT task, the…

Neural mechanisms of cue-approach training

PubMed Central

Bakkour, Akram; Lewis-Peacock, Jarrod A.; Poldrack, Russell A.; Schonberg, Tom

2016-01-01

Biasing choices may prove a useful way to implement behavior change. Previous work has shown that a simple training task (the cue-approach task), which does not rely on external reinforcement, can robustly influence choice behavior by biasing choice toward items that were targeted during training. In the current study, we replicate previous behavioral findings and explore the neural mechanisms underlying the shift in preferences following cue-approach training. Given recent successes in the development and application of machine learning techniques to task-based fMRI data, which have advanced understanding of the neural substrates of cognition, we sought to leverage the power of these techniques to better understand neural changes during cue-approach training that subsequently led to a shift in choice behavior. Contrary to our expectations, we found that machine learning techniques applied to fMRI data during non-reinforced training were unsuccessful in elucidating the neural mechanism underlying the behavioral effect. However, univariate analyses during training revealed that the relationship between BOLD and choices for Go items increases as training progresses compared to choices of NoGo items primarily in lateral prefrontal cortical areas. This new imaging finding suggests that preferences are shifted via differential engagement of task control networks that interact with value networks during cue-approach training. PMID:27677231

Mechanisms of impulsive choice: III. The role of reward processes

PubMed Central

Marshall, Andrew T.

2015-01-01

Two experiments examined the relationship between reward processing and impulsive choice. In Experiment 1, rats chose between a smaller-sooner (SS) reward (1 pellet, 10 s) and a larger-later (LL) reward (1, 2, and 4 pellets, 30 s). The rats then experienced concurrent variable-interval 30-s schedules with variations in reward magnitude to evaluate reward magnitude discrimination. LL choice behavior positively correlated with reward magnitude discrimination. In Experiment 2, rats chose between an SS reward (1 pellet, 10 s) and an LL reward (2 and 4 pellets, 30 s). The rats then received either a reward intervention which consisted of concurrent fixed-ratio schedules associated with different magnitudes to improve their reward magnitude discrimination, or a control task. All rats then experienced a post-intervention impulsive choice task followed by a reward magnitude discrimination task to assess intervention efficacy. The rats that received the intervention exhibited increases in post-intervention LL choice behavior, and made more responses for larger-reward magnitudes in the reward magnitude discrimination task, suggesting that the intervention heightened sensitivities to reward magnitude. The results suggest that reward magnitude discrimination plays a key role in individual differences in impulsive choice, and could be a potential target for further intervention developments. PMID:26506254

Prospects for Observing Ultracompact Binaries with Space-Based Gravitational Wave Interferometers and Optical Telescopes

NASA Technical Reports Server (NTRS)

Littenberg, T. B.; Larson, S. L.; Nelemans, G.; Cornish, N. J.

2012-01-01

Space-based gravitational wave interferometers are sensitive to the galactic population of ultracompact binaries. An important subset of the ultracompact binary population are those stars that can be individually resolved by both gravitational wave interferometers and electromagnetic telescopes. The aim of this paper is to quantify the multimessenger potential of space-based interferometers with arm-lengths between 1 and 5 Gm. The Fisher information matrix is used to estimate the number of binaries from a model of the Milky Way which are localized on the sky by the gravitational wave detector to within 1 and 10 deg(exp 2) and bright enough to be detected by a magnitude-limited survey.We find, depending on the choice ofGW detector characteristics, limiting magnitude and observing strategy, that up to several hundred gravitational wave sources could be detected in electromagnetic follow-up observations.

Are the O stars in WR+O binaries exceptionally rapid rotators?

NASA Astrophysics Data System (ADS)

Reeve, Dominic; Howarth, Ian D.

2018-05-01

We examine claims of strong gravity-darkening effects in the O-star components of WR+O binaries. We generate synthetic spectra for a wide range of parameters, and show that the line-width results are consistent with extensive measurements of O stars that are either single or are members of `normal' binaries. By contrast, the WR+O results are at the extremes of, or outside, the distributions of both models and other observations. Remeasurement of the WR+O spectra shows that they can be reconciled with other results by judicious choice of pseudo-continuum normalization. With this interpretation, the supersynchronous rotation previously noted for the O-star components in the WR+O binaries with the longest orbital periods appears to be unexceptional. Our investigation is therefore consistent with the aphorism that if the title of a paper ends with a question mark, the answer is probably `no'.

Noradrenergic modulation of vicarious trial-and-error behavior during a spatial decision-making task in rats.

PubMed

Amemiya, S; Noji, T; Kubota, N; Nishijima, T; Kita, I

2014-04-18

Deliberation between possible options before making a decision is crucial to responding with an optimal choice. However, the neural mechanisms regulating this deliberative decision-making process are still unclear. Recent studies have proposed that the locus coeruleus-noradrenaline (LC-NA) system plays a role in attention, behavioral flexibility, and exploration, which contribute to the search for an optimal choice under uncertain situations. In the present study, we examined whether the LC-NA system relates to the deliberative process in a T-maze spatial decision-making task in rats. To quantify deliberation in rats, we recorded vicarious trial-and-error behavior (VTE), which is considered to reflect a deliberative process exploring optimal choices. In experiment 1, we manipulated the difficulty of choice by varying the amount of reward pellets between the two maze arms (0 vs. 4, 1 vs. 3, 2 vs. 2). A difficulty-dependent increase in VTE was accompanied by a reduction of choice bias toward the high reward arm and an increase in time required to select one of the two arms in the more difficult manipulation. In addition, the increase of c-Fos-positive NA neurons in the LC depended on the task difficulty and the amount of c-Fos expression in LC-NA neurons positively correlated with the occurrence of VTE. In experiment 2, we inhibited LC-NA activity by injection of clonidine, an agonist of the alpha2 autoreceptor, during a decision-making task (1 vs. 3). The clonidine injection suppressed occurrence of VTE in the early phase of the task and subsequently impaired a valuable choice later in the task. These results suggest that the LC-NA system regulates the deliberative process during decision-making. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Affective and cognitive mechanisms of risky decision making.

PubMed

Shimp, Kristy G; Mitchell, Marci R; Beas, B Sofia; Bizon, Jennifer L; Setlow, Barry

2015-01-01

The ability to make advantageous decisions under circumstances in which there is a risk of adverse consequences is an important component of adaptive behavior; however, extremes in risk taking (either high or low) can be maladaptive and are characteristic of a number of neuropsychiatric disorders. To better understand the contributions of various affective and cognitive factors to risky decision making, cohorts of male Long-Evans rats were trained in a "Risky Decision making Task" (RDT), in which they made discrete trial choices between a small, "safe" food reward and a large, "risky" food reward accompanied by varying probabilities of footshock. Experiment 1 evaluated the relative contributions of the affective stimuli (i.e., punishment vs. reward) to RDT performance by parametrically varying the magnitudes of the footshock and large reward. Varying the shock magnitude had a significant impact on choice of the large, "risky" reward, such that greater magnitudes were associated with reduced choice of the large reward. In contrast, varying the large, "risky" reward magnitude had minimal influence on reward choice. Experiment 2 compared individual variability in RDT performance with performance in an attentional set shifting task (assessing cognitive flexibility), a delayed response task (assessing working memory), and a delay discounting task (assessing impulsive choice). Rats characterized as risk averse in the RDT made more perseverative errors on the set shifting task than did their risk taking counterparts, whereas RDT performance was not related to working memory abilities or impulsive choice. In addition, rats that showed greater delay discounting (greater impulsive choice) showed corresponding poorer performance in the working memory task. Together, these results suggest that reward-related decision making under risk of punishment is more strongly influenced by the punishment than by the reward, and that risky and impulsive decision making are associated with distinct components of executive function. Copyright © 2014 Elsevier Inc. All rights reserved.

I Plan Therefore I Choose: Free-Choice Bias Due to Prior Action-Probability but Not Action-Value

PubMed Central

Suriya-Arunroj, Lalitta; Gail, Alexander

2015-01-01

According to an emerging view, decision-making, and motor planning are tightly entangled at the level of neural processing. Choice is influenced not only by the values associated with different options, but also biased by other factors. Here we test the hypothesis that preliminary action planning can induce choice biases gradually and independently of objective value when planning overlaps with one of the potential action alternatives. Subjects performed center-out reaches obeying either a clockwise or counterclockwise cue-response rule in two tasks. In the probabilistic task, a pre-cue indicated the probability of each of the two potential rules to become valid. When the subsequent rule-cue unambiguously indicated which of the pre-cued rules was actually valid (instructed trials), subjects responded faster to rules pre-cued with higher probability. When subjects were allowed to choose freely between two equally rewarded rules (choice trials) they chose the originally more likely rule more often and faster, despite the lack of an objective advantage in selecting this target. In the amount task, the pre-cue indicated the amount of potential reward associated with each rule. Subjects responded faster to rules pre-cued with higher reward amount in instructed trials of the amount task, equivalent to the more likely rule in the probabilistic task. Yet, in contrast, subjects showed hardly any choice bias and no increase in response speed in favor of the original high-reward target in the choice trials of the amount task. We conclude that free-choice behavior is robustly biased when predictability encourages the planning of one of the potential responses, while prior reward expectations without action planning do not induce such strong bias. Our results provide behavioral evidence for distinct contributions of expected value and action planning in decision-making and a tight interdependence of motor planning and action selection, supporting the idea that the underlying neural mechanisms overlap. PMID:26635565

A chain-retrieval model for voluntary task switching.

PubMed

Vandierendonck, André; Demanet, Jelle; Liefooghe, Baptist; Verbruggen, Frederick

2012-09-01

To account for the findings obtained in voluntary task switching, this article describes and tests the chain-retrieval model. This model postulates that voluntary task selection involves retrieval of task information from long-term memory, which is then used to guide task selection and task execution. The model assumes that the retrieved information consists of acquired sequences (or chains) of tasks, that selection may be biased towards chains containing more task repetitions and that bottom-up triggered repetitions may overrule the intended task. To test this model, four experiments are reported. In Studies 1 and 2, sequences of task choices and the corresponding transition sequences (task repetitions or switches) were analyzed with the help of dependency statistics. The free parameters of the chain-retrieval model were estimated on the observed task sequences and these estimates were used to predict autocorrelations of tasks and transitions. In Studies 3 and 4, sequences of hand choices and their transitions were analyzed similarly. In all studies, the chain-retrieval model yielded better fits and predictions than statistical models of event choice. In applications to voluntary task switching (Studies 1 and 2), all three parameters of the model were needed to account for the data. When no task switching was required (Studies 3 and 4), the chain-retrieval model could account for the data with one or two parameters clamped to a neutral value. Implications for our understanding of voluntary task selection and broader theoretical implications are discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

Using a discrete choice experiment to value the QLU-C10D: feasibility and sensitivity to presentation format.

PubMed

Norman, R; Viney, R; Aaronson, N K; Brazier, J E; Cella, D; Costa, D S J; Fayers, P M; Kemmler, G; Peacock, S; Pickard, A S; Rowen, D; Street, D J; Velikova, G; Young, T A; King, M T

2016-03-01

To assess the feasibility of using a discrete choice experiment (DCE) to value health states within the QLU-C10D, a utility instrument derived from the QLQ-C30, and to assess clarity, difficulty, and respondent preference between two presentation formats. We ran a DCE valuation task in an online panel (N = 430). Respondents answered 16 choice pairs; in half of these, differences between dimensions were highlighted, and in the remainder, common dimensions were described in text and differing attributes were tabulated. To simplify the cognitive task, only four of the QLU-C10D's ten dimensions differed per choice set. We assessed difficulty and clarity of the valuation task with Likert-type scales, and respondents were asked which format they preferred. We analysed the DCE data by format with a conditional logit model and used Chi-squared tests to compare other responses by format. Semi-structured telephone interviews (N = 8) explored respondents' cognitive approaches to the valuation task. Four hundred and forty-nine individuals were recruited, 430 completed at least one choice set, and 422/449 (94 %) completed all 16 choice sets. Interviews revealed that respondents found ten domains difficult but manageable, many adopting simplifying heuristics. Results for clarity and difficulty were identical between formats, but the "highlight" format was preferred by 68 % of respondents. Conditional logit parameter estimates were monotonic within domains, suggesting respondents were able to complete the DCE sensibly, yielding valid results. A DCE valuation task in which only four of the QLU-C10D's ten dimensions differed in any choice set is feasible for deriving utility weights for the QLU-C10D.

Simulation study to determine the impact of different design features on design efficiency in discrete choice experiments.

PubMed

Vanniyasingam, Thuva; Cunningham, Charles E; Foster, Gary; Thabane, Lehana

2016-07-19

Discrete choice experiments (DCEs) are routinely used to elicit patient preferences to improve health outcomes and healthcare services. While many fractional factorial designs can be created, some are more statistically optimal than others. The objective of this simulation study was to investigate how varying the number of (1) attributes, (2) levels within attributes, (3) alternatives and (4) choice tasks per survey will improve or compromise the statistical efficiency of an experimental design. A total of 3204 DCE designs were created to assess how relative design efficiency (d-efficiency) is influenced by varying the number of choice tasks (2-20), alternatives (2-5), attributes (2-20) and attribute levels (2-5) of a design. Choice tasks were created by randomly allocating attribute and attribute level combinations into alternatives. Relative d-efficiency was used to measure the optimality of each DCE design. DCE design complexity influenced statistical efficiency. Across all designs, relative d-efficiency decreased as the number of attributes and attribute levels increased. It increased for designs with more alternatives. Lastly, relative d-efficiency converges as the number of choice tasks increases, where convergence may not be at 100% statistical optimality. Achieving 100% d-efficiency is heavily dependent on the number of attributes, attribute levels, choice tasks and alternatives. Further exploration of overlaps and block sizes are needed. This study's results are widely applicable for researchers interested in creating optimal DCE designs to elicit individual preferences on health services, programmes, policies and products. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Probabilistic learning and inference in schizophrenia

PubMed Central

Averbeck, Bruno B.; Evans, Simon; Chouhan, Viraj; Bristow, Eleanor; Shergill, Sukhwinder S.

2010-01-01

Patients with schizophrenia make decisions on the basis of less evidence when required to collect information to make an inference, a behavior often called jumping to conclusions. The underlying basis for this behaviour remains controversial. We examined the cognitive processes underpinning this finding by testing subjects on the beads task, which has been used previously to elicit jumping to conclusions behaviour, and a stochastic sequence learning task, with a similar decision theoretic structure. During the sequence learning task, subjects had to learn a sequence of button presses, while receiving noisy feedback on their choices. We fit a Bayesian decision making model to the sequence task and compared model parameters to the choice behavior in the beads task in both patients and healthy subjects. We found that patients did show a jumping to conclusions style; and those who picked early in the beads task tended to learn less from positive feedback in the sequence task. This favours the likelihood of patients selecting early because they have a low threshold for making decisions, and that they make choices on the basis of relatively little evidence. PMID:20810252

Probabilistic learning and inference in schizophrenia.

PubMed

Averbeck, Bruno B; Evans, Simon; Chouhan, Viraj; Bristow, Eleanor; Shergill, Sukhwinder S

2011-04-01

Patients with schizophrenia make decisions on the basis of less evidence when required to collect information to make an inference, a behavior often called jumping to conclusions. The underlying basis for this behavior remains controversial. We examined the cognitive processes underpinning this finding by testing subjects on the beads task, which has been used previously to elicit jumping to conclusions behavior, and a stochastic sequence learning task, with a similar decision theoretic structure. During the sequence learning task, subjects had to learn a sequence of button presses, while receiving a noisy feedback on their choices. We fit a Bayesian decision making model to the sequence task and compared model parameters to the choice behavior in the beads task in both patients and healthy subjects. We found that patients did show a jumping to conclusions style; and those who picked early in the beads task tended to learn less from positive feedback in the sequence task. This favours the likelihood of patients selecting early because they have a low threshold for making decisions, and that they make choices on the basis of relatively little evidence. Published by Elsevier B.V.

The contribution of recollection and familiarity to recognition memory: a study of the effects of test format and aging.

PubMed

Bastin, Christine; Van der Linden, Martial

2003-01-01

Whether the format of a recognition memory task influences the contribution of recollection and familiarity to performance is a matter of debate. The authors investigated this issue by comparing the performance of 64 young (mean age = 21.7 years; mean education = 14.5 years) and 62 older participants (mean age = 64.4 years; mean education = 14.2 years) on a yes-no and a forced-choice recognition task for unfamiliar faces using the remember-know-guess procedure. Familiarity contributed more to forced-choice than to yes-no performance. Moreover, older participants, who showed a decrease in recollection together with an increase in familiarity, performed better on the forced-choice task than on the yes-no task, whereas younger participants showed the opposite pattern.

Role of dopamine D2 receptors in optimizing choice strategy in a dynamic and uncertain environment

PubMed Central

Kwak, Shinae; Huh, Namjung; Seo, Ji-Seon; Lee, Jung-Eun; Han, Pyung-Lim; Jung, Min W.

2014-01-01

In order to investigate roles of dopamine receptor subtypes in reward-based learning, we examined choice behavior of dopamine D1 and D2 receptor-knockout (D1R-KO and D2R-KO, respectively) mice in an instrumental learning task with progressively increasing reversal frequency and a dynamic two-armed bandit task. Performance of D2R-KO mice was progressively impaired in the former as the frequency of reversal increased and profoundly impaired in the latter even with prolonged training, whereas D1R-KO mice showed relatively minor performance deficits. Choice behavior in the dynamic two-armed bandit task was well explained by a hybrid model including win-stay-lose-switch and reinforcement learning terms. A model-based analysis revealed increased win-stay, but impaired value updating and decreased value-dependent action selection in D2R-KO mice, which were detrimental to maximizing rewards in the dynamic two-armed bandit task. These results suggest an important role of dopamine D2 receptors in learning from past choice outcomes for rapid adjustment of choice behavior in a dynamic and uncertain environment. PMID:25389395

Rats prefer mutual rewards in a prosocial choice task.

PubMed

Hernandez-Lallement, Julen; van Wingerden, Marijn; Marx, Christine; Srejic, Milan; Kalenscher, Tobias

2014-01-01

Pro-sociality, i.e., the preference for outcomes that produce benefits for other individuals, is ubiquitous in humans. Recently, cross-species comparisons of social behavior have offered important new insights into the evolution of pro-sociality. Here, we present a rodent analog of the Pro-social Choice Task that controls strategic components, de-confounds other-regarding choice motives from the animals' natural tendencies to maximize own food access and directly tests the effect of social context on choice allocation. We trained pairs of rats-an actor and a partner rat-in a double T-maze task where actors decided between two alternatives only differing in the reward delivered to the partner. The "own reward" choice yielded a reward only accessible to the actor whereas the "both reward" choice produced an additional reward for a partner (partner condition) or an inanimate toy (toy Condition), located in an adjacent compartment. We found that actors chose "both reward" at levels above chance and more often in the partner than in the toy condition. Moreover, we show that this choice pattern adapts to the current social context and that the observed behavior is stable over time.

Rats prefer mutual rewards in a prosocial choice task

PubMed Central

Hernandez-Lallement, Julen; van Wingerden, Marijn; Marx, Christine; Srejic, Milan; Kalenscher, Tobias

2015-01-01

Pro-sociality, i.e., the preference for outcomes that produce benefits for other individuals, is ubiquitous in humans. Recently, cross-species comparisons of social behavior have offered important new insights into the evolution of pro-sociality. Here, we present a rodent analog of the Pro-social Choice Task that controls strategic components, de-confounds other-regarding choice motives from the animals' natural tendencies to maximize own food access and directly tests the effect of social context on choice allocation. We trained pairs of rats—an actor and a partner rat—in a double T-maze task where actors decided between two alternatives only differing in the reward delivered to the partner. The “own reward” choice yielded a reward only accessible to the actor whereas the “both reward” choice produced an additional reward for a partner (partner condition) or an inanimate toy (toy Condition), located in an adjacent compartment. We found that actors chose “both reward” at levels above chance and more often in the partner than in the toy condition. Moreover, we show that this choice pattern adapts to the current social context and that the observed behavior is stable over time. PMID:25642162

Is a bird in the hand worth two in the future? Intertemporal choice, attachment and theory of mind in school-aged children.

PubMed

Marchetti, Antonella; Castelli, Ilaria; Sanvito, Laura; Massaro, Davide

2014-01-01

Intertemporal choice is a decision-making dilemma related to outcomes of different entity located at different time points. Economic and psychological literature on this topic showed the phenomen of temporal discounting, i.e., the proclivity to devalue the outcome distant in time on the basis of the time delay necessary to obtain it. The goals of this research are to investigate two different components of intertemporal choice separately, namely time and outcome, in school-age children, and the possible link among such components and the security of attachment style and theory of mind. Ninety one children aged between 6 and 10 years performed two intertemporal choice tasks, first and second order false belief tasks and the Separation Anxiety Task in the Family and School versions. Results showed that the two components of intertemporal choice (waiting tolerance and sensitivity to delayed outcome) are stately interrelated; the quality of the attachment to the family caregiver affects the tolerance to waiting time and first order false belief understanding affects both the components of intertemporal choice.

Is a bird in the hand worth two in the future? Intertemporal choice, attachment and theory of mind in school-aged children

PubMed Central

Marchetti, Antonella; Castelli, Ilaria; Sanvito, Laura; Massaro, Davide

2014-01-01

Intertemporal choice is a decision-making dilemma related to outcomes of different entity located at different time points. Economic and psychological literature on this topic showed the phenomen of temporal discounting, i.e., the proclivity to devalue the outcome distant in time on the basis of the time delay necessary to obtain it. The goals of this research are to investigate two different components of intertemporal choice separately, namely time and outcome, in school-age children, and the possible link among such components and the security of attachment style and theory of mind. Ninety one children aged between 6 and 10 years performed two intertemporal choice tasks, first and second order false belief tasks and the Separation Anxiety Task in the Family and School versions. Results showed that the two components of intertemporal choice (waiting tolerance and sensitivity to delayed outcome) are stately interrelated; the quality of the attachment to the family caregiver affects the tolerance to waiting time and first order false belief understanding affects both the components of intertemporal choice. PMID:24904496

Comparison of two gas chromatograph models and analysis of binary data

NASA Technical Reports Server (NTRS)

Keba, P. S.; Woodrow, P. T.

1972-01-01

The overall objective of the gas chromatograph system studies is to generate fundamental design criteria and techniques to be used in the optimum design of the system. The particular tasks currently being undertaken are the comparison of two mathematical models of the chromatograph and the analysis of binary system data. The predictions of two mathematical models, an equilibrium absorption model and a non-equilibrium absorption model exhibit the same weaknesses in their inability to predict chromatogram spreading for certain systems. The analysis of binary data using the equilibrium absorption model confirms that, for the systems considered, superposition of predicted single component behaviors is a first order representation of actual binary data. Composition effects produce non-idealities which limit the rigorous validity of superposition.

Decision-Making under Ambiguity Is Modulated by Visual Framing, but Not by Motor vs. Non-Motor Context. Experiments and an Information-Theoretic Ambiguity Model

PubMed Central

Grau-Moya, Jordi; Ortega, Pedro A.; Braun, Daniel A.

2016-01-01

A number of recent studies have investigated differences in human choice behavior depending on task framing, especially comparing economic decision-making to choice behavior in equivalent sensorimotor tasks. Here we test whether decision-making under ambiguity exhibits effects of task framing in motor vs. non-motor context. In a first experiment, we designed an experience-based urn task with varying degrees of ambiguity and an equivalent motor task where subjects chose between hitting partially occluded targets. In a second experiment, we controlled for the different stimulus design in the two tasks by introducing an urn task with bar stimuli matching those in the motor task. We found ambiguity attitudes to be mainly influenced by stimulus design. In particular, we found that the same subjects tended to be ambiguity-preferring when choosing between ambiguous bar stimuli, but ambiguity-avoiding when choosing between ambiguous urn sample stimuli. In contrast, subjects’ choice pattern was not affected by changing from a target hitting task to a non-motor context when keeping the stimulus design unchanged. In both tasks subjects’ choice behavior was continuously modulated by the degree of ambiguity. We show that this modulation of behavior can be explained by an information-theoretic model of ambiguity that generalizes Bayes-optimal decision-making by combining Bayesian inference with robust decision-making under model uncertainty. Our results demonstrate the benefits of information-theoretic models of decision-making under varying degrees of ambiguity for a given context, but also demonstrate the sensitivity of ambiguity attitudes across contexts that theoretical models struggle to explain. PMID:27124723

Decision-Making under Ambiguity Is Modulated by Visual Framing, but Not by Motor vs. Non-Motor Context. Experiments and an Information-Theoretic Ambiguity Model.

PubMed

Grau-Moya, Jordi; Ortega, Pedro A; Braun, Daniel A

2016-01-01

A number of recent studies have investigated differences in human choice behavior depending on task framing, especially comparing economic decision-making to choice behavior in equivalent sensorimotor tasks. Here we test whether decision-making under ambiguity exhibits effects of task framing in motor vs. non-motor context. In a first experiment, we designed an experience-based urn task with varying degrees of ambiguity and an equivalent motor task where subjects chose between hitting partially occluded targets. In a second experiment, we controlled for the different stimulus design in the two tasks by introducing an urn task with bar stimuli matching those in the motor task. We found ambiguity attitudes to be mainly influenced by stimulus design. In particular, we found that the same subjects tended to be ambiguity-preferring when choosing between ambiguous bar stimuli, but ambiguity-avoiding when choosing between ambiguous urn sample stimuli. In contrast, subjects' choice pattern was not affected by changing from a target hitting task to a non-motor context when keeping the stimulus design unchanged. In both tasks subjects' choice behavior was continuously modulated by the degree of ambiguity. We show that this modulation of behavior can be explained by an information-theoretic model of ambiguity that generalizes Bayes-optimal decision-making by combining Bayesian inference with robust decision-making under model uncertainty. Our results demonstrate the benefits of information-theoretic models of decision-making under varying degrees of ambiguity for a given context, but also demonstrate the sensitivity of ambiguity attitudes across contexts that theoretical models struggle to explain.

Towards a ternary NIRS-BCI: single-trial classification of verbal fluency task, Stroop task and unconstrained rest

NASA Astrophysics Data System (ADS)

Schudlo, Larissa C.; Chau, Tom

2015-12-01

Objective. The majority of near-infrared spectroscopy (NIRS) brain-computer interface (BCI) studies have investigated binary classification problems. Limited work has considered differentiation of more than two mental states, or multi-class differentiation of higher-level cognitive tasks using measurements outside of the anterior prefrontal cortex. Improvements in accuracies are needed to deliver effective communication with a multi-class NIRS system. We investigated the feasibility of a ternary NIRS-BCI that supports mental states corresponding to verbal fluency task (VFT) performance, Stroop task performance, and unconstrained rest using prefrontal and parietal measurements. Approach. Prefrontal and parietal NIRS signals were acquired from 11 able-bodied adults during rest and performance of the VFT or Stroop task. Classification was performed offline using bagging with a linear discriminant base classifier trained on a 10 dimensional feature set. Main results. VFT, Stroop task and rest were classified at an average accuracy of 71.7% ± 7.9%. The ternary classification system provided a statistically significant improvement in information transfer rate relative to a binary system controlled by either mental task (0.87 ± 0.35 bits/min versus 0.73 ± 0.24 bits/min). Significance. These results suggest that effective communication can be achieved with a ternary NIRS-BCI that supports VFT, Stroop task and rest via measurements from the frontal and parietal cortices. Further development of such a system is warranted. Accurate ternary classification can enhance communication rates offered by NIRS-BCIs, improving the practicality of this technology.

Task Characteristics, Managerial Socialization, and Media Selection.

ERIC Educational Resources Information Center

Donabedian, Bairj; McKinnon, Sharon M.; Bruns, William J., Jr.

1998-01-01

Questions why managers choose one communication medium in preference to another. Proposes a role for social factors in media selection. Finds, employing a large field-collected sample, strong support for Information Richness Theory, a rational-choice model connecting managers' media choice to task characteristics like variety and analyzability.…

Probability matching in risky choice: the interplay of feedback and strategy availability.

PubMed

Newell, Ben R; Koehler, Derek J; James, Greta; Rakow, Tim; van Ravenzwaaij, Don

2013-04-01

Probability matching in sequential decision making is a striking violation of rational choice that has been observed in hundreds of experiments. Recent studies have demonstrated that matching persists even in described tasks in which all the information required for identifying a superior alternative strategy-maximizing-is present before the first choice is made. These studies have also indicated that maximizing increases when (1) the asymmetry in the availability of matching and maximizing strategies is reduced and (2) normatively irrelevant outcome feedback is provided. In the two experiments reported here, we examined the joint influences of these factors, revealing that strategy availability and outcome feedback operate on different time courses. Both behavioral and modeling results showed that while availability of the maximizing strategy increases the choice of maximizing early during the task, feedback appears to act more slowly to erode misconceptions about the task and to reinforce optimal responding. The results illuminate the interplay between "top-down" identification of choice strategies and "bottom-up" discovery of those strategies via feedback.

Fast optimization of binary clusters using a novel dynamic lattice searching method.

PubMed

Wu, Xia; Cheng, Wen

2014-09-28

Global optimization of binary clusters has been a difficult task despite of much effort and many efficient methods. Directing toward two types of elements (i.e., homotop problem) in binary clusters, two classes of virtual dynamic lattices are constructed and a modified dynamic lattice searching (DLS) method, i.e., binary DLS (BDLS) method, is developed. However, it was found that the BDLS can only be utilized for the optimization of binary clusters with small sizes because homotop problem is hard to be solved without atomic exchange operation. Therefore, the iterated local search (ILS) method is adopted to solve homotop problem and an efficient method based on the BDLS method and ILS, named as BDLS-ILS, is presented for global optimization of binary clusters. In order to assess the efficiency of the proposed method, binary Lennard-Jones clusters with up to 100 atoms are investigated. Results show that the method is proved to be efficient. Furthermore, the BDLS-ILS method is also adopted to study the geometrical structures of (AuPd)79 clusters with DFT-fit parameters of Gupta potential.

A two-step initial mass function:. Consequences of clustered star formation for binary properties

NASA Astrophysics Data System (ADS)

Durisen, R. H.; Sterzik, M. F.; Pickett, B. K.

2001-06-01

If stars originate in transient bound clusters of moderate size, these clusters will decay due to dynamic interactions in which a hard binary forms and ejects most or all the other stars. When the cluster members are chosen at random from a reasonable initial mass function (IMF), the resulting binary characteristics do not match current observations. We find a significant improvement in the trends of binary properties from this scenario when an additional constraint is taken into account, namely that there is a distribution of total cluster masses set by the masses of the cloud cores from which the clusters form. Two distinct steps then determine final stellar masses - the choice of a cluster mass and the formation of the individual stars. We refer to this as a ``two-step'' IMF. Simple statistical arguments are used in this paper to show that a two-step IMF, combined with typical results from dynamic few-body system decay, tends to give better agreement between computed binary characteristics and observations than a one-step mass selection process.

General simulation algorithm for autocorrelated binary processes.

PubMed

Serinaldi, Francesco; Lombardo, Federico

2017-02-01

The apparent ubiquity of binary random processes in physics and many other fields has attracted considerable attention from the modeling community. However, generation of binary sequences with prescribed autocorrelation is a challenging task owing to the discrete nature of the marginal distributions, which makes the application of classical spectral techniques problematic. We show that such methods can effectively be used if we focus on the parent continuous process of beta distributed transition probabilities rather than on the target binary process. This change of paradigm results in a simulation procedure effectively embedding a spectrum-based iterative amplitude-adjusted Fourier transform method devised for continuous processes. The proposed algorithm is fully general, requires minimal assumptions, and can easily simulate binary signals with power-law and exponentially decaying autocorrelation functions corresponding, for instance, to Hurst-Kolmogorov and Markov processes. An application to rainfall intermittency shows that the proposed algorithm can also simulate surrogate data preserving the empirical autocorrelation.

Momentary Conscious Pairing Eliminates Unconscious-Stimulus Influences on Task Selection

PubMed Central

Zhou, Fanzhi Anita; Davis, Greg

2012-01-01

Task selection, previously thought to operate only under conscious, voluntary control, can be activated by unconsciously-perceived stimuli. In most cases, such activation is observed for unconscious stimuli that closely resemble other conscious, task-relevant stimuli and hence may simply reflect perceptual activation of consciously established stimulus-task associations. However, other studies have reported ‘direct’ unconscious-stimulus influences on task selection in the absence of any conscious, voluntary association between that stimulus and task (e.g., Zhou and Davis, 2012). In new experiments, described here, these latter influences on cued- and free-choice task selection appear robust and long-lived, yet, paradoxically, are suppressed to undetectable levels following momentary conscious prime-task pairing. Assessing, and rejecting, three intuitive explanations for such suppressive effects, we conclude that conscious prime-task pairing minimizes non-strategic influences of unconscious stimuli on task selection, insulating endogenous choice mechanisms from maladaptive external control. PMID:23050012

Analog Computer-Aided Detection (CAD) information can be more effective than binary marks.

PubMed

Cunningham, Corbin A; Drew, Trafton; Wolfe, Jeremy M

2017-02-01

In socially important visual search tasks, such as baggage screening and diagnostic radiology, experts miss more targets than is desirable. Computer-aided detection (CAD) programs have been developed specifically to improve performance in these professional search tasks. For example, in breast cancer screening, many CAD systems are capable of detecting approximately 90% of breast cancer, with approximately 0.5 false-positive detections per image. Nevertheless, benefits of CAD in clinical settings tend to be small (Birdwell, 2009) or even absent (Meziane et al., 2011; Philpotts, 2009). The marks made by a CAD system can be "binary," giving the same signal to any location where the signal is above some threshold. Alternatively, a CAD system presents an analog signal that reflects strength of the signal at a location. In the experiments reported, we compare analog and binary CAD presentations using nonexpert observers and artificial stimuli defined by two noisy signals: a visible color signal and an "invisible" signal that informed our simulated CAD system. We found that analog CAD generally yielded better overall performance than binary CAD. The analog benefit is similar at high and low target prevalence. Our data suggest that the form of the CAD signal can directly influence performance. Analog CAD may allow the computer to be more helpful to the searcher.

Differential effects of social and novelty enrichment on individual differences in impulsivity and behavioral flexibility.

PubMed

Wang, Maya Zhe; Marshall, Andrew T; Kirkpatrick, Kimberly

2017-06-01

Early life experience profoundly impacts behavior and cognitive functions in rats. The present study investigated how the presence of conspecifics and/or novel objects, could independently influence individual differences in impulsivity and behavioral flexibility. Twenty-four rats were reared in an isolated condition, an isolated condition with a novel object, a pair-housed social condition, or a pair-housed social condition with a novel object. The rats were then tested on an impulsive choice task, a behavioral flexibility task, and an impulsive action task. Novelty enrichment produced an overall increase in impulsive choice, while social enrichment decreased impulsive choice in the absence of novelty enrichment and also produced an overall increase in impulsive action. In the behavioral flexibility task, social enrichment increased regressive errors, whereas both social and novelty enrichment reduced never-reinforced errors. Individual differences analyses indicated a significant relationship between performance in the behavioral flexibility and impulsive action tasks, which may reflect a common psychological correlate of action inhibition. Moreover, there was a relationship between delay sensitivity in the impulsive choice task and performance on the DRL and behavioral flexibility tasks, suggesting a dual role for timing and inhibitory processes in driving the interrelationship between these tasks. Overall, these results indicate that social and novelty enrichment produce distinct effects on impulsivity and adaptability, suggesting the need to parse out the different elements of enrichment in future studies. Further research is warranted to better understand how individual differences in sensitivity to enrichment affect individuals' interactions with and the resulting consequences of the rearing environment. Copyright © 2017 Elsevier B.V. All rights reserved.

Differential effects of social and novelty enrichment on individual differences in impulsivity and behavioral flexibility

PubMed Central

Wang, Maya Zhe; Marshall, Andrew T.; Kirkpatrick, Kimberly

2017-01-01

Early life experience profoundly impacts behavior and cognitive functions in rats. The present study investigated how the presence of conspecifics and/or novel objects, could independently influence individual differences in impulsivity and behavioral flexibility. Twenty-four rats were reared in an isolated condition, an isolated condition with a novel object, a pair-housed social condition, or a pair-housed social condition with a novel object. The rats were then tested on an impulsive choice task, a behavioral flexibility task, and an impulsive action task. Novelty enrichment produced an overall increase in impulsive choice, while social enrichment decreased impulsive choice in the absence of novelty enrichment and also produced an overall increase in impulsive action. In the behavioral flexibility task, social enrichment increased regressive errors, whereas both social and novelty enrichment reduced never reinforced errors. Individual differences analyses indicated a significant relationship between performance in the behavioral flexibility and impulsive action tasks, which may reflect a common psychological correlate of action inhibition. Moreover, there was a relationship between delay sensitivity in the impulsive choice task and performance on the DRL and behavioral flexibility tasks, suggesting a dual role for timing and inhibitory processes in driving the interrelationship between these tasks. Overall, these results indicate that social and novelty enrichment produce distinct effects on impulsivity and adaptability, suggesting the need to parse out the different elements of enrichment in future studies. Further research is warranted to better understand how individual differences in sensitivity to enrichment affect individuals’ interactions with and the resulting consequences of the rearing environment. PMID:28341610

Poverty and Economic Decision-Making: Evidence from Changes in Financial Resources at Payday

PubMed Central

Carvalho, Leandro S.; Meier, Stephan; Wang, Stephanie W.

2016-01-01

We study the effect of financial resources on decision-making. Low-income U.S. households are randomly assigned to receive an online survey before or after payday. The survey collects measures of cognitive function and administers risk and intertemporal choice tasks. The study design generates variation in cash, checking and savings balances, and expenditures. Before-payday participants behave as if they are more present-biased when making intertemporal choices about monetary rewards but not when making intertemporal choices about non-monetary real-effort tasks. Nor do we find before-after differences in risk-taking, the quality of decision-making, the performance in cognitive function tasks, or in heuristic judgments. PMID:28003681

Area/lipid of bilayers from NMR.

PubMed Central

Nagle, J F

1993-01-01

Values of area per lipid A ranging from 56 to 72 A 2 have been reported from essentially the same SCD data from DPPC in the L alpha phase. The differences are due primarily to three separate binary choices in interpretation. It is argued that one particular combination is best; this yields A = 62 +/- 2 A 2 for DPPC at 50 degrees C. Each preceding interpretation agrees with at least one of the three present choices and disagrees with at least one. PMID:8324184

Stimulus-response correspondence in go-nogo and choice tasks: Are reactions altered by the presence of an irrelevant salient object?

PubMed

Lien, Mei-Ching; Pedersen, Logan; Proctor, Robert W

2016-11-01

In 2-choice tasks, responses are faster when stimulus location corresponds to response location, even when stimulus location is irrelevant. Dolk et al. (J Exp Psychol Hum Percept Perform 39:1248-1260, 2013a) found this stimulus-response correspondence effect with a single response location in a go-nogo task when an irrelevant Japanese waving cat was present. They argued that salient objects trigger spatial coding of the response relative to that object. We examined this claim using both behavioral and lateralized readiness potential (LRP) measures. In Experiment 1 participants determined the pitch of a left- or right-positioned tone, whereas in Experiment 2 they determined the color of a dot within a centrally located hand pointing left, right, or straight ahead. In both experiments, participants performed a go-nogo task with the right-index finger and a 2-choice task with both index fingers, with a left-positioned Japanese waving cat present or absent. For the go-nogo task, the cat induced a correspondence effect on response times (RT) to the tones (Experiment 1) but not the visual stimuli (Experiment 2). For the 2-choice task, a correspondence effect was evident in all conditions in both experiments. Cat's presence/absence did not significantly modulate the effect for right and left responses, although there was a trend toward increased RT and LRP for right responses in Experiment 1. The results imply that a salient, irrelevant object could provide a reference frame for response coding when attention is available to process it, as is likely in an auditory task (Experiment 1) but not a visual task (Experiment 2).

Appearance Matters: Neural Correlates of Food Choice and Packaging Aesthetics

PubMed Central

Van der Laan, Laura N.; De Ridder, Denise T. D.; Viergever, Max A.; Smeets, Paul A. M.

2012-01-01

Neuro-imaging holds great potential for predicting choice behavior from brain responses. In this study we used both traditional mass-univariate and state-of-the-art multivariate pattern analysis to establish which brain regions respond to preferred packages and to what extent neural activation patterns can predict realistic low-involvement consumer choices. More specifically, this was assessed in the context of package-induced binary food choices. Mass-univariate analyses showed that several regions, among which the bilateral striatum, were more strongly activated in response to preferred food packages. Food choices could be predicted with an accuracy of up to 61.2% by activation patterns in brain regions previously found to be involved in healthy food choices (superior frontal gyrus) and visual processing (middle occipital gyrus). In conclusion, this study shows that mass-univariate analysis can detect small package-induced differences in product preference and that MVPA can successfully predict realistic low-involvement consumer choices from functional MRI data. PMID:22848586

Libration of arguments of circumbinary-planet orbits at resonance

NASA Astrophysics Data System (ADS)

Schubart, Joachim

2017-06-01

The paper refers to fictitious resonant orbits of planet type that surround both components of a binary system. In case of 16 studied examples a suitable choice of the starting values leads to a process of libration of special angular arguments and to an evolution with an at least temporary stay of the planet in the resonant orbit. The ratio of the periods of revolution of the binary and a planet is equal to 1:5. Eight orbits depend on the ratio 1:5 of the masses of the binary components, but two other ratios appear as well. The basis of this study is the planar, elliptic or circular restricted problem of three bodies, but remarks at the end of the text refer to a four-body problem.

Multicategorical Spline Model for Item Response Theory.

ERIC Educational Resources Information Center

Abrahamowicz, Michal; Ramsay, James O.

1992-01-01

A nonparametric multicategorical model for multiple-choice data is proposed as an extension of the binary spline model of J. O. Ramsay and M. Abrahamowicz (1989). Results of two Monte Carlo studies illustrate the model, which approximates probability functions by rational splines. (SLD)

Risk Reduction and Resource Pooling on a Cooperation Task

ERIC Educational Resources Information Center

Pietras, Cynthia J.; Cherek, Don R.; Lane, Scott D.; Tcheremissine, Oleg

2006-01-01

Two experiments investigated choice in adult humans on a simulated cooperation task to evaluate a risk-reduction account of sharing based on the energy-budget rule. The energy-budget rule is an optimal foraging model that predicts risk-averse choices when net energy gains exceed energy requirements (positive energy budget) and risk-prone choices…

Investigating Student Choices in Performing Higher-Level Comprehension Tasks Using TED

ERIC Educational Resources Information Center

Bianchi, Francesca; Marenzi, Ivana

2016-01-01

The current paper describes a first experiment in the use of TED talks and open tagging exercises to train higher-level comprehension skills, and of automatic logging of the student's actions to investigate the student choices while performing analytical tasks. The experiment took advantage of an interactive learning platform--LearnWeb--that…

The Effect of General Creative Personality and Freedom of Task Choice on Adolescents' Social Creativity

ERIC Educational Resources Information Center

Gu, Chuanhua; Hu, Bi Ying; Ngwira, Flemmings Fishani; Jing, Zhi; Zhou, Zongkui

2016-01-01

This study investigated the effect of general creative personality and freedom of task choice on the social creativity of adolescents. The results indicated, first, that senior high school students scored higher than junior high school students. Second, girls scored higher than boys on originality, fluency, flexibility, appropriateness, and…

Choice-specific sequences in parietal cortex during a virtual-navigation decision task

PubMed Central

Harvey, Christopher D.; Coen, Philip; Tank, David W.

2012-01-01

The posterior parietal cortex (PPC) plays an important role in many cognitive behaviors; however, the neural circuit dynamics underlying PPC function are not well understood. Here we optically imaged the spatial and temporal activity patterns of neuronal populations in mice performing a PPC-dependent task that combined a perceptual decision and memory-guided navigation in a virtual environment. Individual neurons had transient activation staggered relative to one another in time, forming a sequence of neuronal activation spanning the entire length of a task trial. Distinct sequences of neurons were triggered on trials with opposite behavioral choices and defined divergent, choice-specific trajectories through a state space of neuronal population activity. Cells participating in the different sequences and at distinct time points in the task were anatomically intermixed over microcircuit length scales (< 100 micrometers). During working memory decision tasks the PPC may therefore perform computations through sequence-based circuit dynamics, rather than long-lived stable states, implemented using anatomically intermingled microcircuits. PMID:22419153

The Elasticity of Preferences.

PubMed

Simon, Dan; Spiller, Stephen A

2016-12-01

We explore how preferences for attributes are constructed when people choose between multiattribute options. As found in prior research, we observed that while people make decisions, their preferences for the attributes in question shift to support the emerging choice, thus enabling confident decisions. The novelty of the studies reported here is that participants repeated the same task 6 to 8 weeks later. We found that between tasks, preferences returned to near their original levels, only to shift again to support the second choice, regardless of which choice participants made. Similar patterns were observed in a free-choice task (Study 1) and when the favorableness of options was manipulated (Study 2). It follows that preferences behave in an elastic manner: In the absence of situational pressures, they rest at baseline levels, but during the process of reaching a decision, they morph to support the chosen options. This elasticity appears to facilitate confident decision making in the face of decisional conflict.

Volition and eye movements.

PubMed

Nachev, Parashkev; Husain, Masud; Kennard, Christopher

2008-01-01

Although the conceptual distinction between voluntary and automatic acts seems intuitively obvious, its neural basis remains opaque. Assigning volition--or some paraphrase such as action selection--to discrete parts of the brain arguably tells us nothing about what volition actually is in neural terms. Equally, exploring the relative sensitivity of discrete brain areas to manipulations of action choice, including its asymptote--free choice--would only be informative if voluntary processes could thereby be reliably isolated. Unfortunately, such manipulations are subject to ineliminable confounds, such as the complexity of the underlying condition-action associations. Here we propose an adaptation of a classic oculomotor task--saccadic choice with asynchronous targets--where the processes engaged in free choice manifest as interference in the performance of an automatic task, thereby circumventing the difficulties in parameterising volition. We suggest that this task may be useful in probing deficits in voluntary action in pathological states.

Affective and cognitive decision-making in adolescents.

PubMed

van Duijvenvoorde, Anna C K; Jansen, Brenda R J; Visser, Ingmar; Huizenga, Hilde M

2010-01-01

Adolescents demonstrate impaired decision-making in emotionally arousing situations, yet they appear to exhibit relatively mature decision-making skills in predominantly cognitive, low-arousal situations. In this study we compared adolescents' (13-15 years) performance on matched affective and cognitive decision-making tasks, in order to determine (1) their performance level on each task and (2) whether performance on the cognitive task was associated with performance on the affective task. Both tasks required a comparison of choice dimensions characterized by frequency of loss, amount of loss, and constant gain. Results indicated that in the affective task, adolescents performed sub-optimally by considering only the frequency of loss, whereas in the cognitive task adolescents used relatively mature decision rules by considering two or all three choice dimensions. Performance on the affective task was not related to performance on the cognitive task. These results are discussed in light of neural developmental trajectories observed in adolescence.

The hybrid delay task: Can capuchin monkeys (Cebus apella) sustain a delay after an initial choice to do so?

PubMed Central

Paglieri, Fabio; Focaroli, Valentina; Bramlett, Jessica; Tierno, Valeria; McIntyre, Joseph M.; Addessi, Elsa; Evans, Theodore A.; Beran, Michael J.

2013-01-01

Choosing to wait for a better outcome (delay choice) and sustaining the delay prior to that outcome (delay maintenance) are both prerequisites for successful self control in intertemporal choices. However, most existing experimental methods test these skills in isolation from each other, and no significant correlation has been observed in performance across these tasks. In this study we introduce a new paradigm, the hybrid delay task, which combines an initial delay choice with a subsequent delay maintenance stage. This allows testing how often choosing to wait is paired with the actual ability to do so. We tested 18 capuchin monkeys (Cebus apella) from two laboratories in various conditions, and we found that subjects frequently chose the delayed reward but then failed to wait for it, due to poor delay maintenance. However, performance improved with experience and different behavioral responses for error correction were evident. These findings have far reaching implications: if such a high error rate was observed also in other species (possibly including Homo sapiens), this may indicate that delay choice tasks that make use of salient, prepotent stimuli do not reliably assess generalized self control, insofar as choosing to wait does not entail always being able to do so. PMID:23274585

Chronic antioxidant and mitochondrial cofactor administration improves discrimination learning in aged but not young dogs.

PubMed

Siwak, Christina T; Tapp, P Dwight; Head, Elizabeth; Zicker, Steven C; Murphey, Heather L; Muggenburg, Bruce A; Ikeda-Douglas, Candace J; Cotman, Carl W; Milgram, Norton W

2005-03-01

The present experiment was part of a 3-year longitudinal study examining the effects of age and antioxidant treatment on cognitive decline in beagles. Two size-concept tasks were administered following pretraining on a series of two-choice (six subtests) and three-choice size discrimination tasks. Thirty-nine young and aged dogs were matched for age and cognitive ability then divided into four treatment groups. A combined antioxidant-mitochondrial cofactor treatment led to significantly improved performance in aged dogs on the first subtest of the two-choice size discrimination series. Treated aged dogs did not significantly differ from the young. Aged dogs on the antioxidant diet continued to perform better than aged controls on the second and third subtests, but these effects did not achieve significance. Young dogs performed significantly better than the aged dogs on the second and third subtests. The remaining two-choice tasks of the discrimination series were comparatively easy, leading to a floor effect. The antioxidant animals performed better on the three-choice size discrimination, but not on the two size-concept tasks. Antioxidants improved the performance of aged dogs on the initial learning tests, suggesting a selective improvement of factors related to the aging process and specific cognitive processes rather than general cognitive enhancement.

Glucocorticoid Regulation of Food-Choice Behavior in Humans: Evidence from Cushing's Syndrome

PubMed Central

Moeller, Scott J.; Couto, Lizette; Cohen, Vanessa; Lalazar, Yelena; Makotkine, Iouri; Williams, Nia; Yehuda, Rachel; Goldstein, Rita Z.; Geer, Eliza B.

2016-01-01

The mechanisms by which glucocorticoids regulate food intake and resulting body mass in humans are not well-understood. One potential mechanism could involve modulation of reward processing, but human stress models examining effects of glucocorticoids on behavior contain important confounds. Here, we studied individuals with Cushing's syndrome, a rare endocrine disorder characterized by chronic excess endogenous glucocorticoids. Twenty-three patients with Cushing's syndrome (13 with active disease; 10 with disease in remission) and 15 controls with a comparably high body mass index (BMI) completed two simulated food-choice tasks (one with “explicit” task contingencies and one with “probabilistic” task contingencies), during which they indicated their objective preference for viewing high calorie food images vs. standardized pleasant, unpleasant, and neutral images. All participants also completed measures of food craving, and approximately half of the participants provided 24-h urine samples for assessment of cortisol and cortisone concentrations. Results showed that on the explicit task (but not the probabilistic task), participants with active Cushing's syndrome made fewer food-related choices than participants with Cushing's syndrome in remission, who in turn made fewer food-related choices than overweight controls. Corroborating this group effect, higher urine cortisone was negatively correlated with food-related choice in the subsample of all participants for whom these data were available. On the probabilistic task, despite a lack of group differences, higher food-related choice correlated with higher state and trait food craving in active Cushing's patients. Taken together, relative to overweight controls, Cushing's patients, particularly those with active disease, displayed a reduced vigor of responding for food rewards that was presumably attributable to glucocorticoid abnormalities. Beyond Cushing's, these results may have relevance for elucidating glucocorticoid contributions to food-seeking behavior, enhancing mechanistic understanding of weight fluctuations associated with oral glucocorticoid therapy and/or chronic stress, and informing the neurobiology of neuropsychiatric conditions marked by abnormal cortisol dynamics (e.g., major depression, Alzheimer's disease). PMID:26903790

Glucocorticoid Regulation of Food-Choice Behavior in Humans: Evidence from Cushing's Syndrome.

PubMed

Moeller, Scott J; Couto, Lizette; Cohen, Vanessa; Lalazar, Yelena; Makotkine, Iouri; Williams, Nia; Yehuda, Rachel; Goldstein, Rita Z; Geer, Eliza B

2016-01-01

The mechanisms by which glucocorticoids regulate food intake and resulting body mass in humans are not well-understood. One potential mechanism could involve modulation of reward processing, but human stress models examining effects of glucocorticoids on behavior contain important confounds. Here, we studied individuals with Cushing's syndrome, a rare endocrine disorder characterized by chronic excess endogenous glucocorticoids. Twenty-three patients with Cushing's syndrome (13 with active disease; 10 with disease in remission) and 15 controls with a comparably high body mass index (BMI) completed two simulated food-choice tasks (one with "explicit" task contingencies and one with "probabilistic" task contingencies), during which they indicated their objective preference for viewing high calorie food images vs. standardized pleasant, unpleasant, and neutral images. All participants also completed measures of food craving, and approximately half of the participants provided 24-h urine samples for assessment of cortisol and cortisone concentrations. Results showed that on the explicit task (but not the probabilistic task), participants with active Cushing's syndrome made fewer food-related choices than participants with Cushing's syndrome in remission, who in turn made fewer food-related choices than overweight controls. Corroborating this group effect, higher urine cortisone was negatively correlated with food-related choice in the subsample of all participants for whom these data were available. On the probabilistic task, despite a lack of group differences, higher food-related choice correlated with higher state and trait food craving in active Cushing's patients. Taken together, relative to overweight controls, Cushing's patients, particularly those with active disease, displayed a reduced vigor of responding for food rewards that was presumably attributable to glucocorticoid abnormalities. Beyond Cushing's, these results may have relevance for elucidating glucocorticoid contributions to food-seeking behavior, enhancing mechanistic understanding of weight fluctuations associated with oral glucocorticoid therapy and/or chronic stress, and informing the neurobiology of neuropsychiatric conditions marked by abnormal cortisol dynamics (e.g., major depression, Alzheimer's disease).

The Additive Effects of Choice and Control.

ERIC Educational Resources Information Center

Karbowski, Joseph; And Others

In separate research studies, students who were given a choice of learning materials or who had control over aversive noise, demonstrated higher motivation and better task performance. To investigate the additive effects of choice and control on perception of control, 80 male and female college students participated in a 2 (choice vs. no-choice) X…

Sex Differences in Risk Preference and c-Fos Expression in Paraventricular Thalamic Nucleus of Rats During Gambling Task

PubMed Central

Ishii, Hironori; Onodera, Mariko; Ohara, Shinya; Tsutsui, Ken-Ichiro; Iijima, Toshio

2018-01-01

Different biological requirements between males and females may cause sex differences in decision preference when choosing between taking a risk to get a higher gain or taking a lower but sure gain. Several studies have tested this assumption in rats, however the conclusion remains controversial because the previous real-world like gambling tasks contained a learning component to track a global payoff of probabilistic outcome in addition to risk preference. Therefore, we modified a simple gambling task allowing us to exclude such learning effect, and investigated the sex difference in risk preference of rats and its neural basis. The task required water deprived rats to choose between a risky option which provided four drops of water or no reward at a 50% random chance vs. a sure option which provided predictable amount x (x = 1, 2, 3, 4). The amount and the risk were explicitly instructed so that different choice conditions could be tested trial by trial without re-learning of reward contingency. Although both sexes correctly chose the sure option with the same level of accuracy when the sure option provided the best offer (x = 4), they exhibited different choice performances when two options had the same expected value (x = 2). Males and females both preferred to take risky choices than sure choices (risk seeking), but males were more risk seeking than females. Outcome-history analysis of their choice pattern revealed that females reduced their risk preference after losing risky choices, whereas males did not. Rather, as losses continued, reaction time for subsequent risky choices got shorter in males. Given that significant sex difference features mainly emerged after negative experiences, male and female rats may evaluate an unsuccessful outcome of their decision in different manners. Furthermore, c-Fos expression in the paraventricular nucleus of the thalamus (PV) was higher in the gambling task than for the control task in males while c-fos levels did not differ in females. The present study provides a clear evidence of sex differences in risk preference in rats and suggests that the PV is a candidate region contributing to sex differences in risky decision making. PMID:29692713

Control and Effort Costs Influence the Motivational Consequences of Choice

PubMed Central

Sullivan-Toole, Holly; Richey, John A.; Tricomi, Elizabeth

2017-01-01

The act of making a choice, apart from any outcomes the choice may yield, has, paradoxically, been linked to both the enhancement and the detriment of intrinsic motivation. Research has implicated two factors in potentially mediating these contradictory effects: the personal control conferred by a choice and the costs associated with a choice. Across four experiments, utilizing a physical effort task disguised as a simple video game, we systematically varied costs across two levels of physical effort requirements (Low-Requirement, High-Requirement) and control over effort costs across three levels of choice (Free-Choice, Restricted-Choice, and No-Choice) to disambiguate how these factors affect the motivational consequences of choosing within an effortful task. Together, our results indicated that, in the face of effort requirements, illusory control alone may not sufficiently enhance perceptions of personal control to boost intrinsic motivation; rather, the experience of actual control may be necessary to overcome effort costs and elevate performance. Additionally, we demonstrated that conditions of illusory control, while otherwise unmotivating, can through association with the experience of free-choice, be transformed to have a positive effect on motivation. PMID:28515705

The role of source memory in gambling task decision making.

PubMed

Whitney, Paul; Hinson, John M

2012-01-01

The role of memory in the Iowa Gambling Task (IGT) was tested in two experiments that dissociated item memory (memory for losses obtained) from source memory (the deck that produced a given loss). In Experiment 1, participants observed 75 choices that had been made by controls or patients in previous research, followed by memory tests, and then 25 active choices from the participant. In Experiment 2, participants made choices for 75 trials, performed the memory tests, and then made 25 final choices. The data show that item and source memory can diverge within the IGT, and that source memory makes a significant contribution to IGT performance.

Motor heuristics and embodied choices: how to choose and act.

PubMed

Raab, Markus

2017-08-01

Human performance requires choosing what to do and how to do it. The goal of this theoretical contribution is to advance understanding of how the motor and cognitive components of choices are intertwined. From a holistic perspective I extend simple heuristics that have been tested in cognitive tasks to motor tasks, coining the term motor heuristics. Similarly I extend the concept of embodied cognition, that has been tested in simple sensorimotor processes changing decisions, to complex sport behavior coining the term embodied choices. Thus both motor heuristics and embodied choices explain complex behavior such as studied in sport and exercise psychology. Copyright © 2017 Elsevier Ltd. All rights reserved.

Choice in multitasking: how delays in the primary task turn a rational into an irrational multitasker.

PubMed

Katidioti, Ioanna; Taatgen, Niels A

2014-06-01

The objective was to establish the nature of choice in cognitive multitasking. Laboratory studies of multitasking suggest people are rational in their switch choices regarding multitasking, whereas observational studies suggest they are not. Threaded cognition theory predicts that switching is opportunistic and depends on availability of cognitive resources. A total of 21 participants answered e-mails by looking up information (similar to customer service employees) while being interrupted by chat messages. They were free to choose when to switch to the chat message. We analyzed the switching behavior and the time they needed to complete the primary mail task. When participants are faced with a delay in the e-mail task, they switch more often to the chat task at high-workload points. Choosing to switch to the secondary task instead of waiting makes them slower. It also makes them forget the information in the e-mail task half of the time, which slows them down even more. When many cognitive resources are available, the probability of switching from one task to another is high. This does not necessarily lead to optimal switching behavior. Potential applications of this research include the minimization of delays in task design and the inability or discouragement of switching in high-workload moments.

Flexible link functions in nonparametric binary regression with Gaussian process priors.

PubMed

Li, Dan; Wang, Xia; Lin, Lizhen; Dey, Dipak K

2016-09-01

In many scientific fields, it is a common practice to collect a sequence of 0-1 binary responses from a subject across time, space, or a collection of covariates. Researchers are interested in finding out how the expected binary outcome is related to covariates, and aim at better prediction in the future 0-1 outcomes. Gaussian processes have been widely used to model nonlinear systems; in particular to model the latent structure in a binary regression model allowing nonlinear functional relationship between covariates and the expectation of binary outcomes. A critical issue in modeling binary response data is the appropriate choice of link functions. Commonly adopted link functions such as probit or logit links have fixed skewness and lack the flexibility to allow the data to determine the degree of the skewness. To address this limitation, we propose a flexible binary regression model which combines a generalized extreme value link function with a Gaussian process prior on the latent structure. Bayesian computation is employed in model estimation. Posterior consistency of the resulting posterior distribution is demonstrated. The flexibility and gains of the proposed model are illustrated through detailed simulation studies and two real data examples. Empirical results show that the proposed model outperforms a set of alternative models, which only have either a Gaussian process prior on the latent regression function or a Dirichlet prior on the link function. © 2015, The International Biometric Society.

Flexible Link Functions in Nonparametric Binary Regression with Gaussian Process Priors

PubMed Central

Li, Dan; Lin, Lizhen; Dey, Dipak K.

2015-01-01

Summary In many scientific fields, it is a common practice to collect a sequence of 0-1 binary responses from a subject across time, space, or a collection of covariates. Researchers are interested in finding out how the expected binary outcome is related to covariates, and aim at better prediction in the future 0-1 outcomes. Gaussian processes have been widely used to model nonlinear systems; in particular to model the latent structure in a binary regression model allowing nonlinear functional relationship between covariates and the expectation of binary outcomes. A critical issue in modeling binary response data is the appropriate choice of link functions. Commonly adopted link functions such as probit or logit links have fixed skewness and lack the flexibility to allow the data to determine the degree of the skewness. To address this limitation, we propose a flexible binary regression model which combines a generalized extreme value link function with a Gaussian process prior on the latent structure. Bayesian computation is employed in model estimation. Posterior consistency of the resulting posterior distribution is demonstrated. The flexibility and gains of the proposed model are illustrated through detailed simulation studies and two real data examples. Empirical results show that the proposed model outperforms a set of alternative models, which only have either a Gaussian process prior on the latent regression function or a Dirichlet prior on the link function. PMID:26686333

The effect of attention loading on the inhibition of choice reaction time to visual motion by concurrent rotary motion

NASA Technical Reports Server (NTRS)

Looper, M.

1976-01-01

This study investigates the influence of attention loading on the established intersensory effects of passive bodily rotation on choice reaction time (RT) to visual motion. Subjects sat at the center of rotation in an enclosed rotating chamber and observed an oscilloscope on which were, in the center, a tracking display and, 10 deg left of center, a RT line. Three tracking tasks and a no-tracking control condition were presented to all subjects in combination with the RT task, which occurred with and without concurrent cab rotations. Choice RT to line motions was inhibited (probability less than .001) both when there was simultaneous vestibular stimulation and when there was a tracking task; response latencies lengthened progressively with increased similarity between the RT and tracking tasks. However, the attention conditions did not affect the intersensory effect; the significance of this for the nature of the sensory interaction is discussed.

The nonlinear, complex sequential organization of behavior in schizophrenic patients: neurocognitive strategies and clinical correlations.

PubMed

Paulus, M P; Perry, W; Braff, D L

1999-09-01

Thought disorder is a hallmark of schizophrenia and can be inferred from disorganized behavior. Measures of the sequential organization of behavior are important because they reflect the cognitive processes of the selection and sequencing of behavioral elements, which generate observable and analyzable behavioral patterns. In this context, sequences of choices generated by schizophrenic patients in a two-choice guessing task fluctuate significantly, which reflects an "oscillating dysregulation" between highly predictable and highly unpredictable subsequences within a single test session. In this study, we aimed to clarify the significance of dysregulation by seeing whether demographic, clinical, neuropsychological, and psychological measures predict the degree of dysregulation observed on this two-choice task. Thirty schizophrenic patients repeatedly performed a LEFT or RIGHT key press that was followed by a stimulus, which occurred randomly on the left or right side of the computer screen. Thus, the stimulus location had nothing to do with the key press behavior. The range of key press sequence predictabilities as measured by the dynamical entropy was used to quantify the dysregulation of response sequences and reflects the range of fixity and randomness of the responses. A factor analysis was performed and step-wise multiple regression analyses were used to relate the factor scores to demographic, clinical, symptomatic, Wisconsin Card Sorting Test (WCST), and Rorschach variables. The LEFT/RIGHT key press sequences were determined by three factors: 1) the degree of win-stay/lose-shift strategy; 2) the degree of contextual influence on the current choice; and 3) the degree of dysregulation on the choice task. Demographic and clinical variables did not predict any of the three response patterns on the choice task. In contrast, the WCST and Rorschach test predicted performance on various factors of choice task response patterns. Schizophrenic patients employ several rules, i.e., "win-stay/lose-shift" and "decide according to the previous choice," that fluctuate significantly when generating sequences on this task, confirming that a basic behavioral dysregulation occurs in a single schizophrenic subject across a single test session. The organization or the "temporal architecture" of the behavioral sequences is not related to symptoms per se, but is related to deficits in executive functioning, problem solving, and perceptual organizational abilities.

Affective and cognitive mechanisms of risky decision making

PubMed Central

Shimp, Kristy G.; Mitchell, Marci R.; Beas, B. Sofia; Bizon, Jennifer L.; Setlow, Barry

2014-01-01

The ability to make advantageous decisions under circumstances in which there is a risk of adverse consequences is an important component of adaptive behavior; however, extremes in risk taking (either high or low) can be maladaptive and are characteristic of a number of neuropsychiatric disorders. To better understand the contributions of various affective and cognitive factors to risky decision making, cohorts of male Long-Evans rats were trained in a “Risky Decision making Task” (RDT), in which they made discrete trial choices between a small, “safe” food reward and a large, “risky” food reward accompanied by varying probabilities of footshock. Experiment 1 evaluated the relative contributions of the affective stimuli (i.e., punishment vs. reward) to RDT performance by parametrically varying the magnitudes of the footshock and large reward. Varying the shock magnitude had a significant impact on choice of the large, “risky” reward, such that greater magnitudes were associated with reduced choice of the large reward. In contrast, varying the large, “risky” reward magnitude had minimal influence on reward choice. Experiment 2 compared individual variability in RDT performance with performance in an attentional set shifting task (assessing cognitive flexibility), a delayed response task (assessing working memory), and a delay discounting task (assessing impulsive choice). Rats characterized as risk averse in the RDT made more perseverative errors on the set shifting task than did their risk taking counterparts, whereas RDT performance was not related to working memory abilities or impulsive choice. In addition, rats that showed greater delay discounting (greater impulsive choice) showed corresponding poorer performance in the working memory task. Together, these results suggest that reward-related decision making under risk of punishment is more strongly influenced by the punishment than by the reward, and that risky and impulsive decision making are associated with distinct components of executive function. PMID:24642448

Choice of optimal working fluid for binary power plants at extremely low temperature brine

NASA Astrophysics Data System (ADS)

Tomarov, G. V.; Shipkov, A. A.; Sorokina, E. V.

2016-12-01

The geothermal energy development problems based on using binary power plants utilizing lowpotential geothermal resources are considered. It is shown that one of the possible ways of increasing the efficiency of heat utilization of geothermal brine in a wide temperature range is the use of multistage power systems with series-connected binary power plants based on incremental primary energy conversion. Some practically significant results of design-analytical investigations of physicochemical properties of various organic substances and their influence on the main parameters of the flowsheet and the technical and operational characteristics of heat-mechanical and heat-exchange equipment for binary power plant operating on extremely-low temperature geothermal brine (70°C) are presented. The calculation results of geothermal brine specific flow rate, capacity (net), and other operation characteristics of binary power plants with the capacity of 2.5 MW at using various organic substances are a practical interest. It is shown that the working fluid selection significantly influences on the parameters of the flowsheet and the operational characteristics of the binary power plant, and the problem of selection of working fluid is in the search for compromise based on the priorities in the field of efficiency, safety, and ecology criteria of a binary power plant. It is proposed in the investigations on the working fluid selection of the binary plant to use the plotting method of multiaxis complex diagrams of relative parameters and characteristic of binary power plants. Some examples of plotting and analyzing these diagrams intended to choose the working fluid provided that the efficiency of geothermal brine is taken as main priority.

Unconscious Cognition Isn't that Smart: Modulation of Masked Repetition Priming Effect in the Word Naming Task

ERIC Educational Resources Information Center

Kinoshita, Sachiko; Forster, Kenneth I.; Mozer, Michael C.

2008-01-01

Masked repetition primes produce greater facilitation in naming in a block containing a high, rather than low proportion of repetition trials. [Bodner, G. E., & Masson, M. E. J. (2004). "Beyond binary judgments: Prime-validity modulates masked repetition priming in the naming task". "Memory & Cognition", 32, 1-11] suggested this phenomenon…

Middle School Students' Responses to Two-Tier Tasks

ERIC Educational Resources Information Center

Haja, Shajahan; Clarke, David

2011-01-01

The structure of two-tier testing is such that the first tier consists of a multiple-choice question and the second tier requires justifications for choices of answers made in the first tier. This study aims to evaluate two-tier tasks in "proportion" in terms of students' capacity to write and select justifications and to examine the effect of…

Sex Differences in Mental Rotation Tasks: Not Just in the Mental Rotation Process!

ERIC Educational Resources Information Center

Boone, Alexander P.; Hegarty, Mary

2017-01-01

The paper-and-pencil Mental Rotation Test (Vandenberg & Kuse, 1978) consistently produces large sex differences favoring men (Voyer, Voyer, & Bryden, 1995). In this task, participants select 2 of 4 answer choices that are rotations of a probe stimulus. Incorrect choices (i.e., foils) are either mirror reflections of the probe or…

The Effect of Aging on the Stages of Processing in a Choice Reaction Time Task

ERIC Educational Resources Information Center

Simon, J. Richard; Pouraghabagher, A. Reza

1978-01-01

Two experiments were conducted to determine the effect of aging on encoding and response selection stages of a choice reaction time task. Results suggested reducing stimulus discriminability may affect information processing prior to the encoding stage, but the encoding stage is the primary locus of the slowing which accompanied aging. (Author)

Career Development in the College Years.

ERIC Educational Resources Information Center

Myers, Roger A.

This paper concerns itself with two relatively central issues in career development, life stages and choice behavior and focuses on the tasks of the college counselor in regards to them. Life stages refer to sequential series of tasks to be accomplished within time periods that can be specified. Choice behavior is the on-going process of making a…

Psychopysics of Remembering: To Bias or Not to Bias?

ERIC Educational Resources Information Center

White, K. Geoffrey; Wixted, John T.

2010-01-01

Delayed matching to sample is typically a two-alternative forced-choice procedure with two sample stimuli. In this task the effects of varying the probability of reinforcers for correct choices and the resulting receiver operating characteristic are symmetrical. A version of the task where a sample is present on some trials and absent on others is…

Long-time tails of the green-kubo integrands for a binary mixture

NASA Astrophysics Data System (ADS)

Wood, W. W.

1989-11-01

The long-time tails for the mutual diffusion coefficient, the thermal diffusivity, the thermal conductivity, and the shear and longitudinal viscosities (from which the tail of the bulk viscosity can be calculated) of a nonreactive binary mixture are calculated from mode-coupling theory, and compared with a prior calculation by Pomeau. Three different choices of the thermal forces and currents are considered, with the results found to take their simplest form in the case of the de Groot "double-primed set". The decompositions into the kinetic, potential, and cross terms are given.

A Photometric Study of the Contact Binary System FU Dra

NASA Astrophysics Data System (ADS)

Kaitchuck, R. H.; Hill, R. L.; Corn, A. P.; Gevirtz, J.; Levell, K. L.; Valenti, T. L.

2006-12-01

This paper reports new four-filter CCD observations of the contact binary FU Dra. The Wilson and Devinney model was used to simultaneously fit these light curves and published radial velocity data. The stellar masses, sizes, and densities were calculated. Five additional models involving dark spots, hot spots, and accretion heating were considered as explanations for the light curve asymmetry known as the "O'Connell effect" in FU Dra. No conclusive spot model choice could be made but the Liu and Yang model for accretion heating is an unlikely explanation for the O'Connell effect in FU Dra.

Objective Physiological Measurements but Not Subjective Reports Moderate the Effect of Hunger on Choice Behavior

PubMed Central

Shabat-Simon, Maytal; Shuster, Anastasia; Sela, Tal; Levy, Dino J.

2018-01-01

Hunger is a powerful driver of human behavior, and is therefore of great interest to the study of psychology, economics, and consumer behavior. Assessing hunger levels in experiments is often biased, when using self-report methods, or complex, when using blood tests. We propose a novel way of objectively measuring subjects’ levels of hunger by identifying levels of alpha-amylase (AA) enzyme in their saliva samples. We used this measure to uncover the effect of hunger on different types of choice behaviors. We found that hunger increases risk-seeking behavior in a lottery-choice task, modifies levels of vindictiveness in a social decision-making task, but does not have a detectible effect on economic inconsistency in a budget-set choice task. Importantly, these findings were moderated by AA levels and not by self-report measures. We demonstrate the effects hunger has on choice behavior and the problematic nature of subjective measures of physiological states, and propose to use reliable and valid biologically based methods to overcome these problems. PMID:29875715

Perceived control in rhesus monkeys (Macaca mulatta) - Enhanced video-task performance

NASA Technical Reports Server (NTRS)

Washburn, David A.; Hopkins, William D.; Rumbaugh, Duane M.

1991-01-01

This investigation was designed to determine whether perceived control effects found in humans extend to rhesus monkeys (Macaca mulatta) tested in a video-task format, using a computer-generated menu program, SELECT. Choosing one of the options in SELECT resulted in presentation of five trials of a corresponding task and subsequent return to the menu. In Experiments 1-3, the animals exhibited stable, meaningful response patterns in this task (i.e., they made choices). In Experiment 4, performance on tasks that were selected by the animals significantly exceeded performance on identical tasks when assigned by the experimenter under comparable conditions (e.g., time of day, order, variety). The reliable and significant advantage for performance on selected tasks, typically found in humans, suggests that rhesus monkeys were able to perceive the availability of choices.

A free, easy-to-use, computer-based simple and four-choice reaction time programme: the Deary-Liewald reaction time task.

PubMed

Deary, Ian J; Liewald, David; Nissan, Jack

2011-03-01

Reaction time tasks are used widely in basic and applied psychology. There is a need for an easy-to-use, freely available programme that can run simple and choice reaction time tasks with no special software. We report the development of, and make available, the Deary-Liewald reaction time task. It is initially tested here on 150 participants, aged from 18 to 80, alongside another widely used reaction time device and tests of fluid and crystallised intelligence and processing speed. The new task's parameters perform as expected with respect to age and intelligence differences. The new task's parameters are reliable, and have very high correlations with the existing task. We also provide instructions for downloading and using the new reaction time programme, and we encourage other researchers to use it.

Self-Supervised Video Hashing With Hierarchical Binary Auto-Encoder.

PubMed

Song, Jingkuan; Zhang, Hanwang; Li, Xiangpeng; Gao, Lianli; Wang, Meng; Hong, Richang

2018-07-01

Existing video hash functions are built on three isolated stages: frame pooling, relaxed learning, and binarization, which have not adequately explored the temporal order of video frames in a joint binary optimization model, resulting in severe information loss. In this paper, we propose a novel unsupervised video hashing framework dubbed self-supervised video hashing (SSVH), which is able to capture the temporal nature of videos in an end-to-end learning to hash fashion. We specifically address two central problems: 1) how to design an encoder-decoder architecture to generate binary codes for videos and 2) how to equip the binary codes with the ability of accurate video retrieval. We design a hierarchical binary auto-encoder to model the temporal dependencies in videos with multiple granularities, and embed the videos into binary codes with less computations than the stacked architecture. Then, we encourage the binary codes to simultaneously reconstruct the visual content and neighborhood structure of the videos. Experiments on two real-world data sets show that our SSVH method can significantly outperform the state-of-the-art methods and achieve the current best performance on the task of unsupervised video retrieval.

Self-Supervised Video Hashing With Hierarchical Binary Auto-Encoder

NASA Astrophysics Data System (ADS)

Song, Jingkuan; Zhang, Hanwang; Li, Xiangpeng; Gao, Lianli; Wang, Meng; Hong, Richang

2018-07-01

Existing video hash functions are built on three isolated stages: frame pooling, relaxed learning, and binarization, which have not adequately explored the temporal order of video frames in a joint binary optimization model, resulting in severe information loss. In this paper, we propose a novel unsupervised video hashing framework dubbed Self-Supervised Video Hashing (SSVH), that is able to capture the temporal nature of videos in an end-to-end learning-to-hash fashion. We specifically address two central problems: 1) how to design an encoder-decoder architecture to generate binary codes for videos; and 2) how to equip the binary codes with the ability of accurate video retrieval. We design a hierarchical binary autoencoder to model the temporal dependencies in videos with multiple granularities, and embed the videos into binary codes with less computations than the stacked architecture. Then, we encourage the binary codes to simultaneously reconstruct the visual content and neighborhood structure of the videos. Experiments on two real-world datasets (FCVID and YFCC) show that our SSVH method can significantly outperform the state-of-the-art methods and achieve the currently best performance on the task of unsupervised video retrieval.

Spontaneous prosocial choice by captive bottlenose dolphins, Tursiops truncatus.

PubMed

Nakahara, Fumio; Komaba, Masayuki; Sato, Ryoichi; Ikeda, Hisako; Komaba, Kumiko; Kawakubo, Akihiro

2017-02-01

Dolphins exhibit prosocial behavior across several different contexts. However, only a few experimental studies have investigated the psychological mechanisms underlying this behavior. In this study, we investigated the mechanisms underlying prosociality in bottlenose dolphins (Tursiops truncatus). In the experiments, water shower devices, developed as environmental enrichment items, were used. Two paradigms were used to measure prosociality. The first was the prosocial choice task, involving the subject typically being offered one choice between two options. The first option provided a reward (take a shower) to both the subject and partner (prosocial choice). The second option provided a reward only to the subject (selfish choice). The second paradigm was the giving assistance task, involving the subject being provided a choice between providing instrumental help to the partner (prosocial choice) or doing nothing. It was observed that the subjects chose the prosocial choices in both paradigms. In these experiments, prosocial choices were spontaneously taken without requests from the partners. These results indicated that the dolphins show preference for other-regarding behavior. Copyright © 2016 Elsevier B.V. All rights reserved.

A Preliminary Analysis of Self-Control with Aversive Events: the Effects of Task Magnitude and Delay on the Choices of Children with Autism

PubMed Central

Lerman, Dorothea C; Addison, Laura R; Kodak, Tiffany

2006-01-01

When faced with a choice between two aversive events, a person exhibits self-control by choosing a smaller, more immediate aversive event over a larger, delayed aversive event. Task demands are often aversive to children with autism and other developmental disabilities. The purpose of this study was to evaluate behavioral sensitivity to differences in the amount and delay of tasks as part of a preliminary study on self-control. Participants were 2 children with autism who engaged in problem behavior maintained by escape. Results indicated a lack of self-control with respect to choosing between two aversive tasks and suggested potential strategies for increasing self-control (i.e., choosing a small immediate task over a large delayed task). PMID:16813043

A preliminary analysis of self-control with aversive events: the effects of task magnitude and delay on the choices of children with autism.

PubMed

Lerman, Dorothea C; Addison, Laura R; Kodak, Tiffany

2006-01-01

When faced with a choice between two aversive events, a person exhibits self-control by choosing a smaller, more immediate aversive event over a larger, delayed aversive event. Task demands are often aversive to children with autism and other developmental disabilities. The purpose of this study was to evaluate behavioral sensitivity to differences in the amount and delay of tasks as part of a preliminary study on self-control. Participants were 2 children with autism who engaged in problem behavior maintained by escape. Results indicated a lack of self-control with respect to choosing between two aversive tasks and suggested potential strategies for increasing self-control (i.e., choosing a small immediate task over a large delayed task).

The Ising Decision Maker: a binary stochastic network for choice response time.

PubMed

Verdonck, Stijn; Tuerlinckx, Francis

2014-07-01

The Ising Decision Maker (IDM) is a new formal model for speeded two-choice decision making derived from the stochastic Hopfield network or dynamic Ising model. On a microscopic level, it consists of 2 pools of binary stochastic neurons with pairwise interactions. Inside each pool, neurons excite each other, whereas between pools, neurons inhibit each other. The perceptual input is represented by an external excitatory field. Using methods from statistical mechanics, the high-dimensional network of neurons (microscopic level) is reduced to a two-dimensional stochastic process, describing the evolution of the mean neural activity per pool (macroscopic level). The IDM can be seen as an abstract, analytically tractable multiple attractor network model of information accumulation. In this article, the properties of the IDM are studied, the relations to existing models are discussed, and it is shown that the most important basic aspects of two-choice response time data can be reproduced. In addition, the IDM is shown to predict a variety of observed psychophysical relations such as Piéron's law, the van der Molen-Keuss effect, and Weber's law. Using Bayesian methods, the model is fitted to both simulated and real data, and its performance is compared to the Ratcliff diffusion model. (c) 2014 APA, all rights reserved.

Disruption of self-organized actions in monkeys with progressive MPTP-induced parkinsonism. I. Effects of task complexity.

PubMed

Pessiglione, Mathias; Guehl, Dominique; Hirsch, Etienne C; Féger, Jean; Tremblay, Léon

2004-01-01

Parkinson's disease (PD) is characterized by motor symptoms, usually accompanied by cognitive deficits. The question addressed in this study is whether complexity of routine actions can exacerbate parkinsonian disorders that are often considered to be motor symptoms. To examine this question, we trained four vervet monkeys (Cercopithecus aethiops) to perform three multiple-choice retrieval tasks. In order of ascending complexity, rewards were freely available (task 1), covered with transparent sliding plaques (task 2), and covered with opaque sliding plaques cued by symbols (task 3). Thus, from task 1 to task 2 we added a motor difficulty--the recall of context-adapted movement; and from task 2 to task 3 we added a cognitive difficulty: the recall of symbol-reward associations. The more complex the task, the longer it took to learn, but after extensive training the performance was stable in all tasks, with similar retrieval durations. The monkeys then received systemic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) injections (0.3-0.4 mg/kg) every 4-7 days, until the first motor symptoms appeared. In the course of MPTP intoxication, the behavioural performance declined while the motor symptoms were absent or mild--the retrieval duration increased, and non-initiated choices and hesitations between choices became frequent. Interestingly, this decline was in proportion to task complexity, and was particularly pronounced with the cognitive difficulty. Furthermore, freezing appeared only with the cognitive difficulty. We therefore suggest that everyday cognitive difficulties may exacerbate hypokinesia (lack of initiation, abnormal slowness) and executive disorders (hesitations, freezing) in the early stages of human PD.

The social transmission of metacontrol policies: Mechanisms underlying the interpersonal transfer of persistence and flexibility.

PubMed

Hommel, Bernhard; Colzato, Lorenza S

2017-10-01

Humans often face binary cognitive-control dilemmas, with the choice between persistence and flexibility being a crucial one. Tackling these dilemmas requires metacontrol, i.e., the control of the current cognitive-control policy. As predicted from functional, psychometric, neuroscientific, and modeling approaches, interindividual variability in metacontrol biases towards persistence or flexibility could be demonstrated in metacontrol-sensitive tasks. These biases covary systematically with genetic predispositions regarding mesofrontal and nigrostriatal dopaminergic functioning and the individualistic or collectivistic nature of the cultural background. However, there is also evidence for mood- and meditation-induced intraindividual variability (with negative mood and focused-attention meditation being associated with a bias towards persistence, and positive mood and open-monitoring meditation being associated with a bias towards flexibility), suggesting that genetic and cultural factors do not determine metacontrol settings entirely. We suggest a theoretical framework that explains how genetic predisposition and cultural learning can lead to the implementation of metacontrol defaults, which however can be shifted towards persistence or flexibility by situational factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Minimal perceptrons for memorizing complex patterns

NASA Astrophysics Data System (ADS)

Pastor, Marissa; Song, Juyong; Hoang, Danh-Tai; Jo, Junghyo

2016-11-01

Feedforward neural networks have been investigated to understand learning and memory, as well as applied to numerous practical problems in pattern classification. It is a rule of thumb that more complex tasks require larger networks. However, the design of optimal network architectures for specific tasks is still an unsolved fundamental problem. In this study, we consider three-layered neural networks for memorizing binary patterns. We developed a new complexity measure of binary patterns, and estimated the minimal network size for memorizing them as a function of their complexity. We formulated the minimal network size for regular, random, and complex patterns. In particular, the minimal size for complex patterns, which are neither ordered nor disordered, was predicted by measuring their Hamming distances from known ordered patterns. Our predictions agree with simulations based on the back-propagation algorithm.

Test-retest reliability of behavioral measures of impulsive choice, impulsive action, and inattention.

PubMed

Weafer, Jessica; Baggott, Matthew J; de Wit, Harriet

2013-12-01

Behavioral measures of impulsivity are widely used in substance abuse research, yet relatively little attention has been devoted to establishing their psychometric properties, especially their reliability over repeated administration. The current study examined the test-retest reliability of a battery of standardized behavioral impulsivity tasks, including measures of impulsive choice (i.e., delay discounting, probability discounting, and the Balloon Analogue Risk Task), impulsive action (i.e., the stop signal task, the go/no-go task, and commission errors on the continuous performance task), and inattention (i.e., attention lapses on a simple reaction time task and omission errors on the continuous performance task). Healthy adults (n = 128) performed the battery on two separate occasions. Reliability estimates for the individual tasks ranged from moderate to high, with Pearson correlations within the specific impulsivity domains as follows: impulsive choice (r range: .76-.89, ps < .001); impulsive action (r range: .65-.73, ps < .001); and inattention (r range: .38-.42, ps < .001). Additionally, the influence of day-to-day fluctuations in mood, as measured by the Profile of Mood States, was assessed in relation to variability in performance on each of the behavioral tasks. Change in performance on the delay discounting task was significantly associated with change in positive mood and arousal. No other behavioral measures were significantly associated with mood. In sum, the current analysis demonstrates that behavioral measures of impulsivity are reliable measures and thus can be confidently used to assess various facets of impulsivity as intermediate phenotypes for drug abuse.

Test-retest reliability of behavioral measures of impulsive choice, impulsive action, and inattention

PubMed Central

Weafer, Jessica; Baggott, Matthew J.; de Wit, Harriet

2014-01-01

Behavioral measures of impulsivity are widely used in substance abuse research, yet relatively little attention has been devoted to establishing their psychometric properties, especially their reliability over repeated administration. The current study examined the test-retest reliability of a battery of standardized behavioral impulsivity tasks, including measures of impulsive choice (delay discounting, probability discounting, and the Balloon Analogue Risk Task), impulsive action (the stop signal task, the go/no-go task, and commission errors on the continuous performance task), and inattention (attention lapses on a simple reaction time task and omission errors on the continuous performance task). Healthy adults (n=128) performed the battery on two separate occasions. Reliability estimates for the individual tasks ranged from moderate to high, with Pearson correlations within the specific impulsivity domains as follows: impulsive choice (r = .76 - .89, ps < .001); impulsive action (r = .65 - .73, ps < .001); and inattention (r = .38-.42, ps < .001). Additionally, the influence of day-to-day fluctuations in mood as measured by the Profile of Mood States was assessed in relation to variability in performance on each of the behavioral tasks. Change in performance on the delay discounting task was significantly associated with change in positive mood and arousal. No other behavioral measures were significantly associated with mood. In sum, the current analysis demonstrates that behavioral measures of impulsivity are reliable measures and thus can be confidently used to assess various facets of impulsivity as intermediate phenotypes for drug abuse. PMID:24099351

Breastfeeding or bottled milk? Poverty and feeding choices in the native and immigrant population in Belgium.

PubMed

Vanderlinden, Karen; Levecque, Katia; Van Rossem, Ronan

2015-04-01

In many European countries, mothers in poverty show a preference for bottled milk over breastfeeding. What remains unknown is whether the impact of poverty on feeding choices differs between immigrants and natives. We first assessed whether being born into poverty indicates a higher chance of being bottle-fed, then evaluated whether region of origin of the mother moderates the impact of poverty on feeding choice. Based on population data from nearly all newborns in Belgium in 2004 (N = 34,314), we performed several binary logistic analyses to answer these research questions. Analyses showed a strong difference in feeding choices between native and migrant mothers in poverty: for Belgian mothers, the choice to breastfeed significantly decreased; no such effect was observed for migrant women. Southern European mothers living in poverty have an even higher chance of breastfeeding than those who are better off. We suggest possible explanations and set a direction for future research regarding breastfeeding choices for migrant mothers.

Origin of the computational hardness for learning with binary synapses.

PubMed

Huang, Haiping; Kabashima, Yoshiyuki

2014-11-01

Through supervised learning in a binary perceptron one is able to classify an extensive number of random patterns by a proper assignment of binary synaptic weights. However, to find such assignments in practice is quite a nontrivial task. The relation between the weight space structure and the algorithmic hardness has not yet been fully understood. To this end, we analytically derive the Franz-Parisi potential for the binary perceptron problem by starting from an equilibrium solution of weights and exploring the weight space structure around it. Our result reveals the geometrical organization of the weight space; the weight space is composed of isolated solutions, rather than clusters of exponentially many close-by solutions. The pointlike clusters far apart from each other in the weight space explain the previously observed glassy behavior of stochastic local search heuristics.

Modeling Confidence Judgments, Response Times, and Multiple Choices in Decision Making: Recognition Memory and Motion Discrimination

PubMed Central

Ratcliff, Roger; Starns, Jeffrey J.

2014-01-01

Confidence in judgments is a fundamental aspect of decision making, and tasks that collect confidence judgments are an instantiation of multiple-choice decision making. We present a model for confidence judgments in recognition memory tasks that uses a multiple-choice diffusion decision process with separate accumulators of evidence for the different confidence choices. The accumulator that first reaches its decision boundary determines which choice is made. Five algorithms for accumulating evidence were compared, and one of them produced proportions of responses for each of the choices and full response time distributions for each choice that closely matched empirical data. With this algorithm, an increase in the evidence in one accumulator is accompanied by a decrease in the others so that the total amount of evidence in the system is constant. Application of the model to the data from an earlier experiment (Ratcliff, McKoon, & Tindall, 1994) uncovered a relationship between the shapes of z-transformed receiver operating characteristics and the behavior of response time distributions. Both are explained in the model by the behavior of the decision boundaries. For generality, we also applied the decision model to a 3-choice motion discrimination task and found it accounted for data better than a competing class of models. The confidence model presents a coherent account of confidence judgments and response time that cannot be explained with currently popular signal detection theory analyses or dual-process models of recognition. PMID:23915088

Characterization of children's decision making: sensitivity to punishment frequency, not task complexity.

PubMed

Crone, Eveline A; Bunge, Silvia A; Latenstein, Heleen; van der Molen, Maurits W

2005-06-01

On a gambling task that models real-life decision making, children between ages 7 and 12 perform like patients with bilateral lesions of the ventromedial prefrontal cortex (VMPFC), opting for choices that yield high immediate gains in spite of higher future losses (Crone & Van der Molen, 2004). The current study set out to characterize developmental changes in decision making by varying task complexity and punishment frequency. Three age groups (7-9 years, 10-12 years, 13-15 years) performed two versions of a computerized variant of the original Iowa gambling task. Task complexity was manipulated by varying the number of choices participants could make. Punishment frequency was manipulated by varying the frequency of delayed punishment. Results showed a developmental increase in the sensitivity to future consequences, which was present only when the punishment was presented infrequently. These results could not be explained by differential sensitivity to task complexity, hypersensitivity to reward, or failure to switch response set after receiving punishment. There was a general pattern of boys outperforming girls by making more advantageous choices over the course of the task. In conclusion, 7-12-year-old children--like VMPFC patients--appear myopic about the future except when the potential for future punishment is high.

Lifespan Changes in Global and Selective Stopping and Performance Adjustments

PubMed Central

van de Laar, Maria C.; van den Wildenberg, Wery P. M.; van Boxtel, Geert J. M.; van der Molen, Maurits W.

2011-01-01

This study examined stopping and performance adjustments in four age groups (M ages: 8, 12, 21, and 76 years). All participants performed on three tasks, a standard two-choice task and the same task in which stop-signal trials were inserted requiring either the suppression of the response activated by the choice stimulus (global stop task) or the suppression of the response when one stop-signal was presented but not when the other stop-signal occurred (selective stop task). The results showed that global stopping was faster than selective stopping in all age groups. Global stopping matured more rapidly than selective stopping. The developmental gain in stopping was considerably more pronounced compared to the loss observed during senescence. All age groups slowed the response on trials without a stop-signal in the stop task compared to trials in the choice task, the elderly in particular. In addition, all age groups slowed on trials following stop-signal trials, except the elderly who did not slow following successful inhibits. By contrast, the slowing following failed inhibits was disproportionally larger in the elderly compared to young adults. Finally, sequential effects did not alter the pattern of performance adjustments. The results were interpreted in terms of developmental change in the balance between proactive and reactive control. PMID:22180746

A Multiple-Choice Task with Changes of Mind

PubMed Central

Albantakis, Larissa; Branzi, Francesca M.; Costa, Albert; Deco, Gustavo

2012-01-01

The role of changes of mind and multiple choices has recently received increased attention in the study of perceptual decision-making. Previously, these extensions to standard two-alternative tasks have been studied separately. Here we explored how changes of mind depend on the number of choice-alternatives. To this end, we tested 14 human subjects on a 2- and 4-alternative direction-discrimination task. Changes of mind in the participants' movement trajectories could be observed for two and for four choice alternatives. With fewer alternatives, participants responded faster and more accurately. The frequency of changes of mind, however, did not significantly differ for the different numbers of choice alternatives. Nevertheless, mind-changing improved the participants' final performance, particularly for intermediate difficulty levels, in both experimental conditions. Moreover, the mean reaction times of individual participants were negatively correlated with their overall tendency to make changes of mind. We further reproduced these findings with a multi-alternative attractor model for decision-making, while a simple race model could not account for the experimental data. Our experiment, combined with the theoretical models allowed us to shed light on: (1) the differences in choice behavior between two and four alternatives, (2) the differences between the data of our human subjects and previous monkey data, (3) individual differences between participants, and (4) the inhibitory interaction between neural representations of choice alternatives. PMID:22916216

Impulsive social influence increases impulsive choices on a temporal discounting task in young adults.

PubMed

Gilman, Jodi M; Curran, Max T; Calderon, Vanessa; Stoeckel, Luke E; Evins, A Eden

2014-01-01

Adolescents and young adults who affiliate with friends who engage in impulsive behavior are more likely to engage in impulsive behaviors themselves, and those who associate with prosocial (i.e. more prudent, future oriented) peers are more likely to engage in prosocial behavior. However, it is difficult to disentangle the contribution of peer influence vs. peer selection (i.e., whether individuals choose friends with similar traits) when interpreting social behaviors. In this study, we combined a novel social manipulation with a well-validated delay discounting task assessing impulsive behavior to create a social influence delay discounting task, in which participants were exposed to both impulsive (smaller, sooner or SS payment) and non-impulsive (larger, later or LL payment) choices from their peers. Young adults in this sample, n = 51, aged 18-25 had a higher rate of SS choices after exposure to impulsive peer influence than after exposure to non-impulsive peer influence. Interestingly, in highly susceptible individuals, the rate of non-impulsive choices did not increase after exposure to non-impulsive influence. There was a positive correlation between self-reported suggestibility and degree of peer influence on SS choices. These results suggest that, in young adults, SS choices appear to be influenced by the choices of same-aged peers, especially for individuals who are highly susceptible to influence.

Impulsive Social Influence Increases Impulsive Choices on a Temporal Discounting Task in Young Adults

PubMed Central

Gilman, Jodi M.; Curran, Max T.; Calderon, Vanessa; Stoeckel, Luke E.; Evins, A. Eden

2014-01-01

Adolescents and young adults who affiliate with friends who engage in impulsive behavior are more likely to engage in impulsive behaviors themselves, and those who associate with prosocial (i.e. more prudent, future oriented) peers are more likely to engage in prosocial behavior. However, it is difficult to disentangle the contribution of peer influence vs. peer selection (i.e., whether individuals choose friends with similar traits) when interpreting social behaviors. In this study, we combined a novel social manipulation with a well-validated delay discounting task assessing impulsive behavior to create a social influence delay discounting task, in which participants were exposed to both impulsive (smaller, sooner or SS payment) and non-impulsive (larger, later or LL payment) choices from their peers. Young adults in this sample, n = 51, aged 18–25 had a higher rate of SS choices after exposure to impulsive peer influence than after exposure to non-impulsive peer influence. Interestingly, in highly susceptible individuals, the rate of non-impulsive choices did not increase after exposure to non-impulsive influence. There was a positive correlation between self-reported suggestibility and degree of peer influence on SS choices. These results suggest that, in young adults, SS choices appear to be influenced by the choices of same-aged peers, especially for individuals who are highly susceptible to influence. PMID:24988440

Iterative quantization: a Procrustean approach to learning binary codes for large-scale image retrieval.

PubMed

Gong, Yunchao; Lazebnik, Svetlana; Gordo, Albert; Perronnin, Florent

2013-12-01

This paper addresses the problem of learning similarity-preserving binary codes for efficient similarity search in large-scale image collections. We formulate this problem in terms of finding a rotation of zero-centered data so as to minimize the quantization error of mapping this data to the vertices of a zero-centered binary hypercube, and propose a simple and efficient alternating minimization algorithm to accomplish this task. This algorithm, dubbed iterative quantization (ITQ), has connections to multiclass spectral clustering and to the orthogonal Procrustes problem, and it can be used both with unsupervised data embeddings such as PCA and supervised embeddings such as canonical correlation analysis (CCA). The resulting binary codes significantly outperform several other state-of-the-art methods. We also show that further performance improvements can result from transforming the data with a nonlinear kernel mapping prior to PCA or CCA. Finally, we demonstrate an application of ITQ to learning binary attributes or "classemes" on the ImageNet data set.

A Galactic Binary Detection Pipeline

NASA Technical Reports Server (NTRS)

Littenberg, Tyson B.

2011-01-01

The Galaxy is suspected to contain hundreds of millions of binary white dwarf systems, a large fraction of which will have sufficiently small orbital period to emit gravitational radiation in band for space-based gravitational wave detectors such as the Laser Interferometer Space Antenna (LISA). LISA's main science goal is the detection of cosmological events (supermassive black hole mergers, etc.) however the gravitational signal from the galaxy will be the dominant contribution to the data - including instrumental noise over approximately two decades in frequency. The catalogue of detectable binary systems will serve as an unparalleled means of studying the Galaxy. Furthermore, to maximize the scientific return from the mission, the data must be "cleansed" of the galactic foreground. We will present an algorithm that can accurately resolve and subtract 2:: 10000 of these sources from simulated data supplied by the Mock LISA Data Challenge Task Force. Using the time evolution of the gravitational wave frequency, we will reconstruct the position of the recovered binaries and show how LISA will sample the entire compact binary population in the Galaxy.

Intake-dependent effects of cocaine self-administration on impulsive choice in a delay discounting task

PubMed Central

Mitchell, Marci R.; Weiss, Virginia G.; Ouimet, Dominique J.; Fuchs, Rita A.; Morgan, Drake; Setlow, Barry

2014-01-01

Cocaine use is associated with high levels of impulsive choice (greater discounting of delayed rewards) in humans, but the cause/effect relationships between cocaine use and impulsive choice are not fully understood. In previous work, we found that both experimenter- and self-administration of fixed quantities of cocaine caused lasting increases in impulsive choice in rats. The present study extended these findings by taking into account baseline impulsive choice prior to self-administration, and by allowing rats free access to cocaine. Male Long-Evans rats were trained in a delay discounting task in which they made discrete-trial choices between small immediate and large delayed food rewards. Half of the rats were then implanted with intravenous catheters and, following recovery, allowed to self-administer cocaine HCl (1.0 mg/kg/infusion) in 6 hour sessions over 14 days. Control rats orally self-administered a sucrose solution under similar conditions. Upon completion of self-administration training, rats remained abstinent for 3 weeks before retesting in the delay discounting task. Cocaine and control groups did not differ prior to self-administration, but afterward, the cocaine group showed greater impulsive choice (fewer choices of large, delayed rewards) than controls. Additional analyses revealed that the effects of cocaine on impulsive choice were intake-dependent; rats classified as “low intake” did not differ from controls, whereas rats classified as “high intake” were significantly more impulsive than both controls and their pre-cocaine baseline. These findings are consistent with the idea that cocaine-induced, pharmacologically based neural adaptations promote the development of impulsive decision making. PMID:24841739

Predicting Social and Communicative Ability in School-Age Children with Autism Spectrum Disorder: A Pilot Study of the Social Attribution Task, Multiple Choice

ERIC Educational Resources Information Center

Burger-Caplan, Rebecca; Saulnier, Celine; Jones, Warren; Klin, Ami

2016-01-01

The Social Attribution Task, Multiple Choice is introduced as a measure of implicit social cognitive ability in children, addressing a key challenge in quantification of social cognitive function in autism spectrum disorder, whereby individuals can often be successful in explicit social scenarios, despite marked social adaptive deficits. The…

An Inexpensive and Automated Method for Presenting Olfactory or Tactile Stimuli to Rats in a Two-Choice Discrimination Task

ERIC Educational Resources Information Center

Iversen, Iver H.

2008-01-01

An inexpensive and automated method for presentation of olfactory or tactile stimuli in a two-choice task for rats was implemented with the use of a computer-controlled bidirectional motor. The motor rotated a disk that presented two stimuli of different texture for tactile discrimination, or different odor for olfactory discrimination. Because…

Numerical black hole initial data with low eccentricity based on post-Newtonian orbital parameters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walther, Benny; Bruegmann, Bernd; Mueller, Doreen

2009-06-15

Black hole binaries on noneccentric orbits form an important subclass of gravitational wave sources, but it is a nontrivial issue to construct numerical initial data with minimal initial eccentricity for numerical simulations. We compute post-Newtonian orbital parameters for quasispherical orbits using the method of Buonanno, Chen and Damour, (2006) and examine the resulting eccentricity in numerical simulations. Four different methods are studied resulting from the choice of Taylor-expanded or effective-one-body Hamiltonians, and from two choices for the energy flux. For equal-mass, nonspinning binaries the approach succeeds in obtaining low-eccentricity numerical initial data with an eccentricity of about e=0.002 for rathermore » small initial separations of D > or approx. 10M. The eccentricity increases for unequal masses and for spinning black holes, but remains smaller than that obtained from previous post-Newtonian approaches. The effective-one-body Hamiltonian offers advantages for decreasing initial separation as expected, but in the context of this study also performs significantly better than the Taylor-expanded Hamiltonian for binaries with spin. For mass ratio 4 ratio 1 and vanishing spin, the eccentricity reaches e=0.004. For mass ratio 1 ratio 1 and aligned spins of size 0.85M{sup 2} the eccentricity is about e=0.07 for the Taylor method and e=0.014 for the effective-one-body method.« less

Decoupled choice-driven and stimulus-related activity in parietal neurons may be misrepresented by choice probabilities.

PubMed

Zaidel, Adam; DeAngelis, Gregory C; Angelaki, Dora E

2017-09-28

Trial-by-trial correlations between neural responses and choices (choice probabilities) are often interpreted to reflect a causal contribution of neurons to task performance. However, choice probabilities may arise from top-down, rather than bottom-up, signals. We isolated distinct sensory and decision contributions to single-unit activity recorded from the dorsal medial superior temporal (MSTd) and ventral intraparietal (VIP) areas of monkeys during perception of self-motion. Superficially, neurons in both areas show similar tuning curves during task performance. However, tuning in MSTd neurons primarily reflects sensory inputs, whereas choice-related signals dominate tuning in VIP neurons. Importantly, the choice-related activity of VIP neurons is not predictable from their stimulus tuning, and these factors are often confounded in choice probability measurements. This finding was confirmed in a subset of neurons for which stimulus tuning was measured during passive fixation. Our findings reveal decoupled stimulus and choice signals in the VIP area, and challenge our understanding of choice signals in the brain.Choice-related signals in neuronal activity may reflect bottom-up sensory processes, top-down decision-related influences, or a combination of the two. Here the authors report that choice-related activity in VIP neurons is not predictable from their stimulus tuning, and that dominant choice signals can bias the standard metric of choice preference (choice probability).

Successful choice behavior is associated with distinct and coherent network states in anterior cingulate cortex

PubMed Central

Lapish, Christopher C.; Durstewitz, Daniel; Chandler, L. Judson; Seamans, Jeremy K.

2008-01-01

Successful decision making requires an ability to monitor contexts, actions, and outcomes. The anterior cingulate cortex (ACC) is thought to be critical for these functions, monitoring and guiding decisions especially in challenging situations involving conflict and errors. A number of different single-unit correlates have been observed in the ACC that reflect the diverse cognitive components involved. Yet how ACC neurons function as an integrated network is poorly understood. Here we show, using advanced population analysis of multiple single-unit recordings from the rat ACC during performance of an ecologically valid decision-making task, that ensembles of neurons move through different coherent and dissociable states as the cognitive requirements of the task change. This organization into distinct network patterns with respect to both firing-rate changes and correlations among units broke down during trials with numerous behavioral errors, especially at choice points of the task. These results point to an underlying functional organization into cell assemblies in the ACC that may monitor choices, outcomes, and task contexts, thus tracking the animal's progression through “task space.” PMID:18708525

Simple real-time computerized tasks for detection of malingering among murderers with schizophrenia.

PubMed

Kertzman, Semion; Grinspan, Haim; Birger, Moshe; Shliapnikov, Nina; Alish, Yakov; Ben Nahum, Zeev; Mester, Roberto; Kotler, Moshe

2006-01-01

It is our contention that computer-based two-alternative forced choice techniques can be useful tools for the detection of patients with schizophrenia who feign acute psychotic symptoms and cognitive impairment as opposed to patients with schizophrenia with a true active psychosis. In our experiment, Visual Simple and Choice Reaction Time tasks were used. Reaction time in milliseconds was recorded and accuracy rate was obtained for all subjects' responses. Both types of task were administered to 27 patients with schizophrenia suspected of having committed murder. Patients with schizophrenia who were clinically assessed as malingerers achieved significantly fewer correct results, were significantly slower and less consistent in their reaction time. Congruence of performance between the Simple and Choice tasks was an additional parameter for the accurate diagnosis of malingering. The four parameters of both tests (accuracy of response, reaction time, standard deviation of reaction time and task congruency) are simple and constitute a user-friendly means for the detection of malingering in forensic practice. Another advantage of this procedure is that the software automatically measures and evaluates all the parameters.

Hold it! The influence of lingering rewards on choice diversification and persistence.

PubMed

Schulze, Christin; van Ravenzwaaij, Don; Newell, Ben R

2017-11-01

Learning to choose adaptively when faced with uncertain and variable outcomes is a central challenge for decision makers. This study examines repeated choice in dynamic probability learning tasks in which outcome probabilities changed either as a function of the choices participants made or independently of those choices. This presence/absence of sequential choice-outcome dependencies was implemented by manipulating a single task aspect between conditions: the retention/withdrawal of reward across individual choice trials. The study addresses how people adapt to these learning environments and to what extent they engage in 2 choice strategies often contrasted as paradigmatic examples of striking violation of versus nominal adherence to rational choice: diversification and persistent probability maximizing, respectively. Results show that decisions approached adaptive choice diversification and persistence when sufficient feedback was provided on the dynamic rules of the probabilistic environments. The findings of divergent behavior in the 2 environments indicate that diversified choices represented a response to the reward retention manipulation rather than to the mere variability of outcome probabilities. Choice in both environments was well accounted for by the generalized matching law, and computational modeling-based strategy analyses indicated that adaptive choice arose mainly from reliance on reinforcement learning strategies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Inconsistency in serial choice decision and motor reaction times dissociate in younger and older adults.

PubMed

Bunce, David; MacDonald, Stuart W S; Hultsch, David F

2004-12-01

Intraindividual variability (inconsistency) in reaction time (RT) latencies was investigated in a group of younger (M=25.46 years) and older (M=69.29 years) men. Both groups performed 300 trials in 2-, 4-, and 8-choice RT conditions where RTs for decision and motor components of the task were recorded separately. A dissociation was evident in that inconsistency was greater in older adults for decision RTs when task demands relating to the number of choices and fatigue arising from time-on-task were high. For younger persons, a weak trend toward greater inconsistency in motor RTs was evident. The results are consistent with accounts suggesting that inconsistency in neurobiological mechanisms increases with age, and that attentional lapses or fluctuations in executive control contribute to RT inconsistency.

The Bulgarian Contribution to the Study of variable stars on observational data from the Kepler mission

NASA Astrophysics Data System (ADS)

Kjurkchieva, D. P.; Dimitrov, D. P.; Radeva, V. S.; Vasileva, D. L.; Atanasova, T. V.; Stateva, I. V.; Petrov, N. I.; Iliev, I. Kh.

2018-02-01

This review paper presents the results of investigations of variable stars obtained by Bulgarian astronomers based on observations of Kepler mission. The main contributions are: determination of orbits and global parameters of more than 100 binary stars; creation of the largest catalog of eccentric stars; identification of sixty new binaries with eccentricity over 0.5; discovery of 19 heartbeat stars; detailed investigation of the spot and flare activity of several binary stars; asteroseismic study of three pulsating stars; detection of deep transits of WD 1145+017 due to its disentangling planet system. The paper illustrates not only scientific significance but also educational and social impact of the work on these tasks.

Comprehension of idioms by children with learning disabilities: metaphoric transparency and syntactic frozenness.

PubMed

Abrahamsen, Eileen P; Burke-Williams, Debra

2004-05-01

Third and fifth grade children with and without learning disabilities participated in this study. Syntactically frozen and flexible idioms and transparent and opaque idioms were used as stimuli to examine the ability to identify the correct idiom and to explain idiom meanings. Grade and diagnostic category affected performance on the explanation task but not on the forced choice task. Idiom type was also a factor affecting comprehension and explanation. Literal responses occurred rarely and were more likely to occur on the forced choice task.

The Relationship between Instructional Variables and Problem Behavior: A Review.

ERIC Educational Resources Information Center

Munk, Dennis D.; Repp, Alan C.

1994-01-01

This paper reviews studies that have used instructional variables as nonaversive interventions for problem behaviors of individuals with severe disabilities. These include student choice of task, task variation, pace of instruction, interspersal of high probability tasks, partial versus whole task training, decreasing task difficulty, and a…

Age-differences in cognitive flexibility when overcoming a preexisting bias through feedback.

PubMed

Wilson, Cristina G; Nusbaum, Amy T; Whitney, Paul; Hinson, John M

2018-08-01

Older adults are often worse than younger adults at adapting to changing situational demands, and this difference is commonly attributed to an age-related decline in acquiring and updating information. Previous research on aging and cognitive flexibility has used measures that require adapting to novel associations learned during a laboratory task (e.g., choice X led to positive outcomes but now leads to negative outcomes). However, in everyday life people must frequently overcome associations based on preexisting beliefs and biases (e.g., you like to eat cake, but your doctor said to limit your sugar intake). The goal of the present study was to examine possible age-differences in overcoming a preexisting bias and determine whether age-related changes in the acquisition and updating of information influence this form of flexibility. Older (n = 20) and younger (n = 20) adults completed a novel task in which repeated choices were made between a sure option (gain or loss) and one of two risky options that were initially ambiguous. Optimal performance required overcoming a framing bias toward being risk seeking to avoid a sure loss and risk averse when offered a sure gain. Probe questions assessed knowledge of choice outcomes, while skin conductance assessed physiological reactions to choices and choice outcomes. Both older and younger adults demonstrated flexibility by reducing the impact of bias over trials, but younger adults had better performance overall. Age-differences were associated with distinct aspects of processing. Young adults had more precise knowledge of choice outcomes and developed skin conductance responses in anticipation of bad choices that were not apparent in older adults. Older adults showed significant improvement over trials in their ability to decrease bias-driven choices, but younger showed greater flexibility. Age-differences in task performance were based on differences in learning and corresponding representations of task-relevant information.

Hold It! The Influence of Lingering Rewards on Choice Diversification and Persistence

ERIC Educational Resources Information Center

Schulze, Christin; van Ravenzwaaij, Don; Newell, Ben R.

2017-01-01

Learning to choose adaptively when faced with uncertain and variable outcomes is a central challenge for decision makers. This study examines repeated choice in dynamic probability learning tasks in which outcome probabilities changed either as a function of the choices participants made or independently of those choices. This presence/absence of…

Orbitofrontal cortical activity during repeated free choice.

PubMed

Campos, Michael; Koppitch, Kari; Andersen, Richard A; Shimojo, Shinsuke

2012-06-01

Neurons in the orbitofrontal cortex (OFC) have been shown to encode subjective values, suggesting a role in preference-based decision-making, although the precise relation to choice behavior is unclear. In a repeated two-choice task, subjective values of each choice can account for aggregate choice behavior, which is the overall likelihood of choosing one option over the other. Individual choices, however, are impossible to predict with knowledge of relative subjective values alone. In this study we investigated the role of internal factors in choice behavior with a simple but novel free-choice task and simultaneous recording from individual neurons in nonhuman primate OFC. We found that, first, the observed sequences of choice behavior included periods of exceptionally long runs of each of two available options and periods of frequent switching. Neither a satiety-based mechanism nor a random selection process could explain the observed choice behavior. Second, OFC neurons encode important features of the choice behavior. These features include activity selective for exceptionally long runs of a given choice (stay selectivity) as well as activity selective for switches between choices (switch selectivity). These results suggest that OFC neural activity, in addition to encoding subjective values on a long timescale that is sensitive to satiety, also encodes a signal that fluctuates on a shorter timescale and thereby reflects some of the statistically improbable aspects of free-choice behavior.

Orbitofrontal cortical activity during repeated free choice

PubMed Central

Koppitch, Kari; Andersen, Richard A.; Shimojo, Shinsuke

2012-01-01

Neurons in the orbitofrontal cortex (OFC) have been shown to encode subjective values, suggesting a role in preference-based decision-making, although the precise relation to choice behavior is unclear. In a repeated two-choice task, subjective values of each choice can account for aggregate choice behavior, which is the overall likelihood of choosing one option over the other. Individual choices, however, are impossible to predict with knowledge of relative subjective values alone. In this study we investigated the role of internal factors in choice behavior with a simple but novel free-choice task and simultaneous recording from individual neurons in nonhuman primate OFC. We found that, first, the observed sequences of choice behavior included periods of exceptionally long runs of each of two available options and periods of frequent switching. Neither a satiety-based mechanism nor a random selection process could explain the observed choice behavior. Second, OFC neurons encode important features of the choice behavior. These features include activity selective for exceptionally long runs of a given choice (stay selectivity) as well as activity selective for switches between choices (switch selectivity). These results suggest that OFC neural activity, in addition to encoding subjective values on a long timescale that is sensitive to satiety, also encodes a signal that fluctuates on a shorter timescale and thereby reflects some of the statistically improbable aspects of free-choice behavior. PMID:22423007

What would you do? The effect of verbal persuasion on task choice.

PubMed

Lamarche, Larkin; Gionfriddo, Alicia M; Cline, Lindsay E; Gammage, Kimberley L; Adkin, Allan L

2014-01-01

Verbal persuasion has been shown to influence psychological and behavioral outcomes. The present study had two objectives: (1) to examine the effect of verbal persuasion on task choice in a balance setting and (2) to evaluate the use of verbal persuasion as an approach to experimentally induce mismatches between perceived and actual balance. Healthy young adults (N=68) completed an 8-m tandem walk task without vision and then were randomly assigned to a feedback group (good, control, or poor), regardless of actual balance. Following the feedback, participants chose to perform the task in one of three conditions differing in level of challenge and also were required to perform the task under the same pre-feedback conditions. Balance efficacy and perceived stability were rated before and after each pre- and post-feedback task, respectively. Balance performance measures were also collected. Following the feedback, participants in the good group were more likely to choose the most challenging task while those in the poor group were more likely to choose the least challenging task. Following the feedback, all groups showed improved balance performance. However, balance efficacy and perceived stability increased for the good and control groups but balance efficacy decreased and perceived stability was unchanged for the poor group. Thus, these findings demonstrate that verbal persuasion can influence task choice and may be used as an approach to experimentally create mismatches between perceived and actual balance. Copyright © 2013 Elsevier B.V. All rights reserved.

Persistence motives in irrational decisions to complete a boring task.

PubMed

Halkjelsvik, Torleif; Rise, Jostein

2015-01-01

We explored a novel task paradigm where participants from the online work marketplace Amazon Mechanical Turk were given the choice to quit or continue an unfinished boring task for identical economic rewards. In Studies 1a and 1b, about half the participants chose to continue (corresponding to an average of 55 and 35 cents in foregone earnings). Participants' self-reported reasons for continuing involved various types of persistence motives, reflecting a desire to persist or complete per se. Studies 2, 3a, 3b, and 3c ruled out the possibility that people continued because they enjoyed the task or believed there were additional rewards for continuing. Study 4 showed that the choice to quit/continue was associated with the manner in which the choice was presented (persistence test vs. decision-making test) and individual differences in dispositional persistence motives. The present data indicate that motivational forces independent of the focal reward may affect intertemporal decisions. © 2014 by the Society for Personality and Social Psychology, Inc.

Developing Pre-Service Teacher Capacity to Make Appropriate Choices of Tasks and Resources through Diagnostic Assessment of Children's Work

ERIC Educational Resources Information Center

Hurst, Chris

2014-01-01

This paper reports on one phase of a long-term project investigating mathematical content knowledge of pre-service teachers. A cohort of second year PSTs conducted a diagnostic assessment and a series of associated tutoring sessions with a primary aged child. The focus here is on the PSTs' ability to make appropriate task choices following the…

Assessing Whether Students Seek Constructive Criticism: The Design of an Automated Feedback System for a Graphic Design Task

ERIC Educational Resources Information Center

Cutumisu, Maria; Blair, Kristen P.; Chin, Doris B.; Schwartz, Daniel L.

2017-01-01

We introduce a choice-based assessment strategy that measures students' choices to seek constructive feedback and to revise their work. We present the feedback system of a game we designed to assess whether students choose positive or negative feedback and choose to revise their posters in the context of a poster design task, where they learn…

Switching between simple cognitive tasks: the interaction of top-down and bottom-up factors

NASA Technical Reports Server (NTRS)

Ruthruff, E.; Remington, R. W.; Johnston, J. C.

2001-01-01

How do top-down factors (e.g., task expectancy) and bottom-up factors (e.g., task recency) interact to produce an overall level of task readiness? This question was addressed by factorially manipulating task expectancy and task repetition in a task-switching paradigm. The effects of expectancy and repetition on response time tended to interact underadditively, but only because the traditional binary task-repetition variable lumps together all switch trials, ignoring variation in task lag. When the task-recency variable was scaled continuously, all 4 experiments instead showed additivity between expectancy and recency. The results indicated that expectancy and recency influence different stages of mental processing. One specific possibility (the configuration-execution model) is that task expectancy affects the time required to configure upcoming central operations, whereas task recency affects the time required to actually execute those central operations.

Choice with Equity: An Assessment by the Koret Task Force on K-12 Education. Hoover Institution Press Publication.

ERIC Educational Resources Information Center

Hill, Paul T., Ed.

This collection of papers reviews the national debate over school choice, examining the benefits for parents, children, and schools and showing how properly designed choice programs can prevent the harmful outcomes choice opponents fear. The papers discuss why choice must be addressed in the context of the real-world performance of public schools,…

Memory modulates journey-dependent coding in the rat hippocampus

PubMed Central

Ferbinteanu, J.; Shirvalkar, P.; Shapiro, M. L.

2011-01-01

Neurons in the rat hippocampus signal current location by firing in restricted areas called place fields. During goal-directed tasks in mazes, place fields can also encode past and future positions through journey-dependent activity, which could guide hippocampus-dependent behavior and underlie other temporally extended memories, such as autobiographical recollections. The relevance of journey-dependent activity for hippocampal-dependent memory, however, is not well understood. To further investigate the relationship between hippocampal journey-dependent activity and memory we compared neural firing in rats performing two mnemonically distinct but behaviorally identical tasks in the plus maze: a hippocampus-dependent spatial navigation task, and a hippocampus-independent cue response task. While place, prospective, and retrospective coding reflected temporally extended behavioral episodes in both tasks, memory strategy altered coding differently before and after the choice point. Before the choice point, when discriminative selection of memory strategy was critical, a switch between the tasks elicited a change in a field’s coding category, so that a field that signaled current location in one task coded pending journeys in the other task. After the choice point, however, when memory strategy became irrelevant, the fields preserved coding categories across tasks, so that the same field consistently signaled either current location or the recent journeys. Additionally, on the start arm firing rates were affected at comparable levels by task and journey, while on the goal arm firing rates predominantly encoded journey. The data demonstrate a direct link between journey-dependent coding and memory, and suggest that episodes are encoded by both population and firing rate coding. PMID:21697365

Effects of Simplifying Choice Tasks on Estimates of Taste Heterogeneity in Stated-Choice Surveys

PubMed Central

Johnson, F. Reed; Ozdemir, Semra; Phillips, Kathryn A

2011-01-01

Researchers usually employ orthogonal arrays or D-optimal designs with little or no attribute overlap in stated-choice surveys. The challenge is to balance statistical efficiency and respondent burden to minimize the overall error in the survey responses. This study examined whether simplifying the choice task, by using a design with more overlap, provides advantages over standard minimum-overlap methods. We administered two designs for eliciting HIV test preferences to split samples. Surveys were undertaken at four HIV testing locations in San Francisco, California. Personal characteristics had different effects on willingness to pay for the two treatments, and gains in statistical efficiency in the minimal-overlap version more than compensated for possible imprecision from increased measurement error. PMID:19880234

Compact binary hashing for music retrieval

NASA Astrophysics Data System (ADS)

Seo, Jin S.

2014-03-01

With the huge volume of music clips available for protection, browsing, and indexing, there is an increased attention to retrieve the information contents of the music archives. Music-similarity computation is an essential building block for browsing, retrieval, and indexing of digital music archives. In practice, as the number of songs available for searching and indexing is increased, so the storage cost in retrieval systems is becoming a serious problem. This paper deals with the storage problem by extending the supervector concept with the binary hashing. We utilize the similarity-preserving binary embedding in generating a hash code from the supervector of each music clip. Especially we compare the performance of the various binary hashing methods for music retrieval tasks on the widely-used genre dataset and the in-house singer dataset. Through the evaluation, we find an effective way of generating hash codes for music similarity estimation which improves the retrieval performance.

Inverting the joint Simon effect by intention.

PubMed

Kiernan, Dovin; Ray, Matthew; Welsh, Timothy N

2012-10-01

The joint Simon effect (JSE) is a spatial-compatibility effect that emerges when two people complete complementary components of a Simon task. In typical JSE studies, two participants sit beside each other and perform go-no-go tasks in which they respond to one of two stimuli by pressing a button. According to the action co-representation account, JSEs emerge because each participant represents their partner's response in addition to their own, causing the same conflicts in processing that would occur if an individual responded to both stimuli (i.e., as in a two-choice task). Because the response buttons are typically in front of participants, however, an alternative explanation is that JSEs are the result of a dimensional overlap between target and response locations coded with respect to another salient object (e.g., the co-actor's effector). To contrast these hypotheses, the participants in the present study completed two-choice and joint Simon tasks in which they were asked to focus on generating an aftereffect in the space contralateral to their response. Hommel (Psychological Research 55:270-279, 1993) previously reported that, when participants completed a two-choice task under such effect-focused instructions, spatial-compatibility effects emerged that were based on the aftereffect location instead of the response location. Consistent with the co-representation account, the results of the present study were that an inverse aftereffect-based (i.e., not a response-location-based) compatibility effect was observed in both the two-choice and joint tasks. The overall pattern of results does not fit with the spatial-coding account and is discussed in the context of the extant JSE literature.

Personality Differences in Career Choice Patterns

ERIC Educational Resources Information Center

Borges, Nicole J.; Roth, Karl S.; Seibel, Hugo R.

2004-01-01

Vocational identity is an important construct for physician career development. Physician vocational development has been grouped into three tasks (crystallization, specification, and implementation) pertaining to career choice and specialty choice (1) In defining the construct of vocational identity, it has been suggested that the relation…

The effects of cognitive load on strategic self-handicapping.

PubMed

Silvera, D H

2000-03-01

Past research has demonstrated that observers tend to underestimate the importance of situational determinants (e.g. task difficulty) of the performances of others. This tendency is particularly pronounced when observers are unmotivated, distracted or otherwise 'cognitively busy' while making attributional judgments. The objective of the present research was to determine whether a similar tendency exists when actors are given the opportunity to choose the tasks they will undertake in a self-presentational situation. Sixty-one participants were given a choice between a difficult and a simple task, with cognitive busyness being manipulated while this choice was being made. Cognitively busy participants were significantly more likely to choose the simple task than their non-busy counterparts.

A PC-based bus monitor program for use with the transport systems research vehicle RS-232 communication interfaces

NASA Technical Reports Server (NTRS)

Easley, Wesley C.

1991-01-01

Experiment critical use of RS-232 data busses in the Transport Systems Research Vehicle (TSRV) operated by the Advanced Transport Operating Systems Program Office at the NASA Langley Research Center has recently increased. Each application utilizes a number of nonidentical computer and peripheral configurations and requires task specific software development. To aid these development tasks, an IBM PC-based RS-232 bus monitoring system was produced. It can simultaneously monitor two communication ports of a PC or clone, including the nonstandard bus expansion of the TSRV Grid laptop computers. Display occurs in a separate window for each port's input with binary display being selectable. A number of other features including binary log files, screen capture to files, and a full range of communication parameters are provided.

Hyperoxia and Hypoxic Hypoxia Effects on Simple and Choice Reaction Times.

PubMed

Dart, Todd; Gallo, Megan; Beer, Jeremy; Fischer, Joseph; Morgan, Thomas; Pilmanis, Andrew

2017-12-01

Effects of exposure to hyperoxia (PiO2 > 105 mmHg), normoxia (PiO2 95-105 mmHg) and hypoxia (PiO2 < 95 mmHg) on simple and choice reaction performance tasks were evaluated. Ten subjects performed simple and choice reaction time tests (SRT and CRT, respectively) at ground level for 40 min (20 min normoxic, 20 min hyperoxic, randomly assigned), 3048 m (10,000 ft) for 75 min (15 min hyperoxic, 60 min hypoxic), 4572 m (15,000 ft) for 60 min (15 min hyperoxic, 45 min hypoxic), and 6096 m (20,000 ft) for 35 min (15 min hyperoxic, 20 min hypoxic). SRT and CRT tests were also conducted at ground level 1 h after normoxic rest (recovery) to assess any recovery time effect on these psychomotor tasks. Total response time (TRT) significantly increased by 15 ms to 25 ms at all three altitudes for both the SRT and CRT tasks. At and below 4572 m, the performance changes were gradual over the duration of the exposures, whereas at 6096 m these changes were immediate. After 1 h, no performance decrement was measured. There was no statistical evidence that ground-level performance on these tasks was improved in hyperoxic vs. normoxic conditions. Results suggest mild decrements in reaction time due to hypoxia may occur as low as 3048 m (10,000 ft) while hyperoxia showed no positive effect on accuracy or reaction time at ground level or higher when performing simple and choice psychomotor reaction tasks.Dart T, Gallo M, Beer J, Fischer J, Morgan T, Pilmanis A. Hyperoxia and hypoxic hypoxia effects on simple and choice reaction times. Aerosp Med Hum Perform. 2017; 88(12):1073-1080.

Α4β2 and α7 nicotinic acetylcholine receptor binding predicts choice preference in two cost benefit decision-making tasks.

PubMed

Mendez, I A; Damborsky, J C; Winzer-Serhan, U H; Bizon, J L; Setlow, B

2013-01-29

Nicotinic receptors have been linked to a wide range of cognitive and behavioral functions, but surprisingly little is known about their involvement in cost benefit decision making. The goal of these experiments was to determine how nicotinic acetylcholine receptor (nAChR) expression is related to two forms of cost benefit decision making. Male Long Evans rats were tested in probability- and delay-discounting tasks, which required discrete trial choices between a small reward and a large reward associated with varying probabilities of omission and varying delays to reward delivery, respectively. Following testing, radioligand binding to α4β2 and α7 nAChR subtypes in brain regions implicated in cost benefit decision making was examined. Significant linear relationships were observed between choice of the large delayed reward in the delay discounting task and α4β2 receptor binding in both the dorsal and ventral hippocampus. Additionally, trends were found suggesting that choice of the large costly reward in both discounting tasks was inversely related to α4β2 receptor binding in the medial prefrontal cortex and nucleus accumbens shell. Similar trends suggested that choice of the large delayed reward in the delay discounting task was inversely related to α4β2 receptor binding in the orbitofrontal cortex, nucleus accumbens core, and basolateral amygdala, as well as to α7 receptor binding in the basolateral amygdala. These data suggest that nAChRs (particularly α4β2) play both unique and common roles in decisions that require consideration of different types of reward costs. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Learning Short Binary Codes for Large-scale Image Retrieval.

PubMed

Liu, Li; Yu, Mengyang; Shao, Ling

2017-03-01

Large-scale visual information retrieval has become an active research area in this big data era. Recently, hashing/binary coding algorithms prove to be effective for scalable retrieval applications. Most existing hashing methods require relatively long binary codes (i.e., over hundreds of bits, sometimes even thousands of bits) to achieve reasonable retrieval accuracies. However, for some realistic and unique applications, such as on wearable or mobile devices, only short binary codes can be used for efficient image retrieval due to the limitation of computational resources or bandwidth on these devices. In this paper, we propose a novel unsupervised hashing approach called min-cost ranking (MCR) specifically for learning powerful short binary codes (i.e., usually the code length shorter than 100 b) for scalable image retrieval tasks. By exploring the discriminative ability of each dimension of data, MCR can generate one bit binary code for each dimension and simultaneously rank the discriminative separability of each bit according to the proposed cost function. Only top-ranked bits with minimum cost-values are then selected and grouped together to compose the final salient binary codes. Extensive experimental results on large-scale retrieval demonstrate that MCR can achieve comparative performance as the state-of-the-art hashing algorithms but with significantly shorter codes, leading to much faster large-scale retrieval.

Search, Memory, and Choice Error: An Experiment

PubMed Central

Sanjurjo, Adam

2015-01-01

Multiple attribute search is a central feature of economic life: we consider much more than price when purchasing a home, and more than wage when choosing a job. An experiment is conducted in order to explore the effects of cognitive limitations on choice in these rich settings, in accordance with the predictions of a new model of search memory load. In each task, subjects are made to search the same information in one of two orders, which differ in predicted memory load. Despite standard models of choice treating such variations in order of acquisition as irrelevant, lower predicted memory load search orders are found to lead to substantially fewer choice errors. An implication of the result for search behavior, more generally, is that in order to reduce memory load (thus choice error) a limited memory searcher ought to deviate from the search path of an unlimited memory searcher in predictable ways-a mechanism that can explain the systematic deviations from optimal sequential search that have recently been discovered in peoples' behavior. Further, as cognitive load is induced endogenously (within the task), and found to affect choice behavior, this result contributes to the cognitive load literature (in which load is induced exogenously), as well as the cognitive ability literature (in which cognitive ability is measured in a separate task). In addition, while the information overload literature has focused on the detrimental effects of the quantity of information on choice, this result suggests that, holding quantity constant, the order that information is observed in is an essential determinant of choice failure. PMID:26121356

Performing a reaching task with one arm while adapting to a visuomotor rotation with the other can lead to complete transfer of motor learning across the arms

PubMed Central

Lei, Yuming; Binder, Jeffrey R.

2015-01-01

The extent to which motor learning is generalized across the limbs is typically very limited. Here, we investigated how two motor learning hypotheses could be used to enhance the extent of interlimb transfer. According to one hypothesis, we predicted that reinforcement of successful actions by providing binary error feedback regarding task success or failure, in addition to terminal error feedback, during initial training would increase the extent of interlimb transfer following visuomotor adaptation (experiment 1). According to the other hypothesis, we predicted that performing a reaching task repeatedly with one arm without providing performance feedback (which prevented learning the task with this arm), while concurrently adapting to a visuomotor rotation with the other arm, would increase the extent of transfer (experiment 2). Results indicate that providing binary error feedback, compared with continuous visual feedback that provided movement direction and amplitude information, had no influence on the extent of transfer. In contrast, repeatedly performing (but not learning) a specific task with one arm while visuomotor adaptation occurred with the other arm led to nearly complete transfer. This suggests that the absence of motor instances associated with specific effectors and task conditions is the major reason for limited interlimb transfer and that reinforcement of successful actions during initial training is not beneficial for interlimb transfer. These findings indicate crucial contributions of effector- and task-specific motor instances, which are thought to underlie (a type of) model-free learning, to optimal motor learning and interlimb transfer. PMID:25632082

Not just for consumers: context effects are fundamental to decision making.

PubMed

Trueblood, Jennifer S; Brown, Scott D; Heathcote, Andrew; Busemeyer, Jerome R

2013-06-01

Context effects--preference changes that depend on the availability of other options--have attracted a great deal of attention among consumer researchers studying high-level decision tasks. In the experiments reported here, we showed that these effects also arise in simple perceptual-decision-making tasks. This finding casts doubt on explanations limited to consumer choice and high-level decisions, and it indicates that context effects may be amenable to a general explanation at the level of the basic decision process. We demonstrated for the first time that three important context effects from the preferential-choice literature--similarity, attraction, and compromise effects--all occurred within a single perceptual-decision task. Not only do our results challenge previous explanations for context effects proposed by consumer researchers, but they also challenge the choice rules assumed in theories of perceptual decision making.

The neural substrates of social influence on decision making.

PubMed

Tomlin, Damon; Nedic, Andrea; Prentice, Deborah A; Holmes, Philip; Cohen, Jonathan D

2013-01-01

The mechanisms that govern human learning and decision making under uncertainty have been the focus of intense behavioral and, more recently, neuroscientific investigation. Substantial progress has been made in building models of the processes involved, and identifying underlying neural mechanisms using simple, two-alternative forced choice decision tasks. However, less attention has been given to how social information influences these processes, and the neural systems that mediate this influence. Here we sought to address these questions by using tasks similar to ones that have been used to study individual decision making behavior, and adding conditions in which participants were given trial-by-trial information about the performance of other individuals (their choices and/or their rewards) simultaneously playing the same tasks. We asked two questions: How does such information about the behavior of others influence performance in otherwise simple decision tasks, and what neural systems mediate this influence? We found that bilateral insula exhibited a parametric relationship to the degree of misalignment of the individual's performance with those of others in the group. Furthermore, activity in the bilateral insula significantly predicted participants' subsequent choices to align their behavior with others in the group when they were misaligned either in their choices (independent of success) or their degree of success (independent of specific choices). These findings add to the growing body of empirical data suggesting that the insula participates in an important way in social information processing and decision making.

High-sucrose diets in male rats disrupt aspects of decision making tasks, motivation and spatial memory, but not impulsivity measured by operant delay-discounting.

PubMed

Wong, Alanna; Dogra, Vimi R; Reichelt, Amy C

2017-06-01

Excessive consumption of sugar sweetened drinks is proposed to produce functional changes in the hippocampus and prefrontal cortex, leading to perturbations in behavioural control. Impairments in behavioural control have been observed in obese people on tasks that involve making choices, including delay-discounting, indicative of increased impulsivity. In this study we examined the impact of 2h daily access to 10% sucrose (or no sucrose in controls) in young male rats on behavioural tasks reliant on hippocampal function including delay-discounting, T-maze forced choice alternation and place recognition memory, as well as progressive ratio to measure motivation. We observed deficits in place recognition memory and T-maze forced choice alternation, indicative of hippocampal deficits in rats with a history of sucrose consumption. Moreover, rats with a history of sucrose consumption were less motivated to lever press for rewards on a progressive ratio schedule. However, rats with a history of sucrose consumption performed equally to control animals during the delay-discounting task, suggesting that they discounted for reward size over a delay in a manner comparable to control animals. These findings indicate that high-sucrose diets impact on spatial and working memory processes, but do not induce impulsive-like choice behaviours in rats, suggesting that unhealthy diet choices may not influence this aspect of decision-making behaviour. Copyright © 2017 Elsevier B.V. All rights reserved.

A multiple maximum scatter difference discriminant criterion for facial feature extraction.

PubMed

Song, Fengxi; Zhang, David; Mei, Dayong; Guo, Zhongwei

2007-12-01

Maximum scatter difference (MSD) discriminant criterion was a recently presented binary discriminant criterion for pattern classification that utilizes the generalized scatter difference rather than the generalized Rayleigh quotient as a class separability measure, thereby avoiding the singularity problem when addressing small-sample-size problems. MSD classifiers based on this criterion have been quite effective on face-recognition tasks, but as they are binary classifiers, they are not as efficient on large-scale classification tasks. To address the problem, this paper generalizes the classification-oriented binary criterion to its multiple counterpart--multiple MSD (MMSD) discriminant criterion for facial feature extraction. The MMSD feature-extraction method, which is based on this novel discriminant criterion, is a new subspace-based feature-extraction method. Unlike most other subspace-based feature-extraction methods, the MMSD computes its discriminant vectors from both the range of the between-class scatter matrix and the null space of the within-class scatter matrix. The MMSD is theoretically elegant and easy to calculate. Extensive experimental studies conducted on the benchmark database, FERET, show that the MMSD out-performs state-of-the-art facial feature-extraction methods such as null space method, direct linear discriminant analysis (LDA), eigenface, Fisherface, and complete LDA.

Distinct and Overlapping Brain Areas Engaged during Value-Based, Mathematical, and Emotional Decision Processing

PubMed Central

Hsu, Chun-Wei; Goh, Joshua O. S.

2016-01-01

When comparing between the values of different choices, human beings can rely on either more cognitive processes, such as using mathematical computation, or more affective processes, such as using emotion. However, the neural correlates of how these two types of processes operate during value-based decision-making remain unclear. In this study, we investigated the extent to which neural regions engaged during value-based decision-making overlap with those engaged during mathematical and emotional processing in a within-subject manner. In a functional magnetic resonance imaging experiment, participants viewed stimuli that always consisted of numbers and emotional faces that depicted two choices. Across tasks, participants decided between the two choices based on the expected value of the numbers, a mathematical result of the numbers, or the emotional face stimuli. We found that all three tasks commonly involved various cortical areas including frontal, parietal, motor, somatosensory, and visual regions. Critically, the mathematical task shared common areas with the value but not emotion task in bilateral striatum. Although the emotion task overlapped with the value task in parietal, motor, and sensory areas, the mathematical task also evoked responses in other areas within these same cortical structures. Minimal areas were uniquely engaged for the value task apart from the other two tasks. The emotion task elicited a more expansive area of neural activity whereas value and mathematical task responses were in more focal regions. Whole-brain spatial correlation analysis showed that valuative processing engaged functional brain responses more similarly to mathematical processing than emotional processing. While decisions on expected value entail both mathematical and emotional processing regions, mathematical processes have a more prominent contribution particularly in subcortical processes. PMID:27375466

Distinct and Overlapping Brain Areas Engaged during Value-Based, Mathematical, and Emotional Decision Processing.

PubMed

Hsu, Chun-Wei; Goh, Joshua O S

2016-01-01

When comparing between the values of different choices, human beings can rely on either more cognitive processes, such as using mathematical computation, or more affective processes, such as using emotion. However, the neural correlates of how these two types of processes operate during value-based decision-making remain unclear. In this study, we investigated the extent to which neural regions engaged during value-based decision-making overlap with those engaged during mathematical and emotional processing in a within-subject manner. In a functional magnetic resonance imaging experiment, participants viewed stimuli that always consisted of numbers and emotional faces that depicted two choices. Across tasks, participants decided between the two choices based on the expected value of the numbers, a mathematical result of the numbers, or the emotional face stimuli. We found that all three tasks commonly involved various cortical areas including frontal, parietal, motor, somatosensory, and visual regions. Critically, the mathematical task shared common areas with the value but not emotion task in bilateral striatum. Although the emotion task overlapped with the value task in parietal, motor, and sensory areas, the mathematical task also evoked responses in other areas within these same cortical structures. Minimal areas were uniquely engaged for the value task apart from the other two tasks. The emotion task elicited a more expansive area of neural activity whereas value and mathematical task responses were in more focal regions. Whole-brain spatial correlation analysis showed that valuative processing engaged functional brain responses more similarly to mathematical processing than emotional processing. While decisions on expected value entail both mathematical and emotional processing regions, mathematical processes have a more prominent contribution particularly in subcortical processes.

Computational models of the Posner simple and choice reaction time tasks

PubMed Central

Feher da Silva, Carolina; Baldo, Marcus V. C.

2015-01-01

The landmark experiments by Posner in the late 1970s have shown that reaction time (RT) is faster when the stimulus appears in an expected location, as indicated by a cue; since then, the so-called Posner task has been considered a “gold standard” test of spatial attention. It is thus fundamental to understand the neural mechanisms involved in performing it. To this end, we have developed a Bayesian detection system and small integrate-and-fire neural networks, which modeled sensory and motor circuits, respectively, and optimized them to perform the Posner task under different cue type proportions and noise levels. In doing so, main findings of experimental research on RT were replicated: the relative frequency effect, suboptimal RTs and significant error rates due to noise and invalid cues, slower RT for choice RT tasks than for simple RT tasks, fastest RTs for valid cues and slowest RTs for invalid cues. Analysis of the optimized systems revealed that the employed mechanisms were consistent with related findings in neurophysiology. Our models predict that (1) the results of a Posner task may be affected by the relative frequency of valid and neutral trials, (2) in simple RT tasks, input from multiple locations are added together to compose a stronger signal, and (3) the cue affects motor circuits more strongly in choice RT tasks than in simple RT tasks. In discussing the computational demands of the Posner task, attention has often been described as a filter that protects the nervous system, whose capacity is limited, from information overload. Our models, however, reveal that the main problems that must be overcome to perform the Posner task effectively are distinguishing signal from external noise and selecting the appropriate response in the presence of internal noise. PMID:26190997

Eye-Gaze Analysis of Facial Emotion Recognition and Expression in Adolescents with ASD.

PubMed

Wieckowski, Andrea Trubanova; White, Susan W

2017-01-01

Impaired emotion recognition and expression in individuals with autism spectrum disorder (ASD) may contribute to observed social impairment. The aim of this study was to examine the role of visual attention directed toward nonsocial aspects of a scene as a possible mechanism underlying recognition and expressive ability deficiency in ASD. One recognition and two expression tasks were administered. Recognition was assessed in force-choice paradigm, and expression was assessed during scripted and free-choice response (in response to emotional stimuli) tasks in youth with ASD (n = 20) and an age-matched sample of typically developing youth (n = 20). During stimulus presentation prior to response in each task, participants' eye gaze was tracked. Youth with ASD were less accurate at identifying disgust and sadness in the recognition task. They fixated less to the eye region of stimuli showing surprise. A group difference was found during the free-choice response task, such that those with ASD expressed emotion less clearly but not during the scripted task. Results suggest altered eye gaze to the mouth region but not the eye region as a candidate mechanism for decreased ability to recognize or express emotion. Findings inform our understanding of the association between social attention and emotion recognition and expression deficits.

The effect of reinforcer magnitude on probability and delay discounting of experienced outcomes in a computer game task in humans.

PubMed

Greenhow, Anna K; Hunt, Maree J; Macaskill, Anne C; Harper, David N

2015-09-01

Delay and uncertainty of receipt both reduce the subjective value of reinforcers. Delay has a greater impact on the subjective value of smaller reinforcers than of larger ones while the reverse is true for uncertainty. We investigated the effect of reinforcer magnitude on discounting of delayed and uncertain reinforcers using a novel approach: embedding relevant choices within a computer game. Participants made repeated choices between smaller, certain, immediate outcomes and larger, but delayed or uncertain outcomes while experiencing the result of each choice. Participants' choices were generally well described by the hyperbolic discounting function. Smaller numbers of points were discounted more steeply than larger numbers as a function of delay but not probability. The novel experiential choice task described is a promising approach to investigating both delay and probability discounting in humans. © Society for the Experimental Analysis of Behavior.

Considering Roads Taken and Not Taken: How Psychological Distance Influences the Framing of Choice Events.

PubMed

Valenti, Greta; Libby, Lisa K

2017-09-01

After people make choices, they can frame the choice event in terms of what they chose, or in terms of what they did not choose. The current research proposes psychological distance as one factor influencing this framing and suggests implications. Three experiments manipulated dimensions of distance to demonstrate people's greater tendency to frame choice events in terms of chosen options at greater psychological distances. Additional findings demonstrate that these effects occur regardless of whether the decision turned out well or poorly. In a final experiment, framing a decision in terms of choosing (versus not choosing) a task made people more likely to believe their choice reflected their liking for the chosen task, which led to more favorable expectations for it. The discussion focuses on possible implications of these findings for understanding prior work on self-other differences in decision making, motivations for past decisions, reactions to decision outcomes, and counterfactual thinking.

Effects of the NMDA receptor antagonists dizocilpine and Ro 63-1908 on delay-discounting and risky decision-making in a gambling task.

PubMed

Higgins, Guy A; Silenieks, Leo B; MacMillan, Cam; Zeeb, Fiona D; Thevarkunnel, Sandy

2018-04-22

Previous studies demonstrated that NMDA receptor antagonists such as dizocilpine (MK801) and the GluN2B NMDA antagonist Ro 63-1908 promote impulsive action (motor impulsivity). The effects of these treatments on impulsive choice and decision-making is less well characterized. Two experiments were undertaken. In the first experiment, given evidence for delay order as a factor in choice selection, the effect of dizocilpine was examined in a delay discounting task with separate groups of male Long-Evans rats trained to a schedule of either ascending (i.e. 0-40 s), or descending delays (i.e. 40-0 s). Under the ascending-delay schedule, dizocilpine (0.03-0.06 mg/kg SC) reduced discounting, yet on the descending-delay schedule discounting was increased. Subgrouping rats according to discounting rate under vehicle pretreatment were consistent with a treatment-induced choice perseveration. In a second experiment, male Long-Evans rats were trained to a gambling task (rGT). Neither dizocilpine (0.01-0.06 mg/kg SC) nor Ro 63-1908 (0.1-1 mg/kg SC) shifted choice from the advantageous to the disadvantageous options. However dizocilpine, and marginally Ro 63-1908, increased choice of the least risky, but suboptimal option. This effect was most evident in rats that initially preferred the disadvantageous options. Consistent with previous studies, both treatments increased measures of motor impulsivity. These results demonstrate that dizocilpine has effects on discounting dependent on delay order and likely reflective of perseveration. On the rGT task, neither dizocilpine nor Ro 63-1908 promoted risky choice, yet both NMDA receptor antagonists increased impulsive action. Copyright © 2018 Elsevier B.V. All rights reserved.

Optimal assessment of multiple cues.

PubMed Central

Fawcett, Tim W; Johnstone, Rufus A

2003-01-01

In a wide range of contexts from mate choice to foraging, animals are required to discriminate between alternative options on the basis of multiple cues. How should they best assess such complex multicomponent stimuli? Here, we construct a model to investigate this problem, focusing on a simple case where a 'chooser' faces a discrimination task involving two cues. These cues vary in their accuracy and in how costly they are to assess. As an example, we consider a mate-choice situation where females choose between males of differing quality. Our model predicts the following: (i) females should become less choosy as the cost of finding new males increases; (ii) females should prioritize cues differently depending on how choosy they are; (iii) females may sometimes prioritize less accurate cues; and (iv) which cues are most important depends on the abundance of desirable mates. These predictions are testable in mate-choice experiments where the costs of choice can be manipulated. Our findings are applicable to other discrimination tasks besides mate choice, for example a predator's choice between palatable and unpalatable prey, or an altruist's choice between kin and non-kin. PMID:12908986

Dismount Threat Recognition through Automatic Pose Identification

DTIC Science & Technology

2012-03-01

10 2.2.2 Enabling Technologies . . . . . . . . . . . . . . 11 2.2.3 Associative Memory Neural Networks . . . . . . 12 III. Methodology...20 3.2.3 Creating Separability . . . . . . . . . . . . . . . 23 3.3 Training the Associative Memory Neural Network... Effects of Parameter and Method Choices . . . . . . . . 30 4.3.1 Decimel versus Bipolar . . . . . . . . . . . . . . 30 4.3.2 Bipolar and Binary Values

A Strategy for Replacing Sum Scoring

ERIC Educational Resources Information Center

Ramsay, James O.; Wiberg, Marie

2017-01-01

This article promotes the use of modern test theory in testing situations where sum scores for binary responses are now used. It directly compares the efficiencies and biases of classical and modern test analyses and finds an improvement in the root mean squared error of ability estimates of about 5% for two designed multiple-choice tests and…

Comprehensive for Who? Neoliberal Directives in Australian "Comprehensive" Sexuality Education and the Erasure of GLBTIQ Identity

ERIC Educational Resources Information Center

Shannon, Barrie

2016-01-01

At present, Australian sex(uality) education curricula aim to equip students with information which facilitates "healthy" sexual choices as they develop. However, this is not neutral information, but rather socially and culturally regulated discourse which encodes a normative binary of sexuality. The largely US-focused sexuality…

Preference uncertainty, preference learning, and paired comparison experiments

Treesearch

David C. Kingsley; Thomas C. Brown

2010-01-01

Results from paired comparison experiments suggest that as respondents progress through a sequence of binary choices they become more consistent, apparently fine-tuning their preferences. Consistency may be indicated by the variance of the estimated valuation distribution measured by the error term in the random utility model. A significant reduction in the variance is...

Dopamine, Effort-Based Choice, and Behavioral Economics: Basic and Translational Research

PubMed Central

Salamone, John D.; Correa, Merce; Yang, Jen-Hau; Rotolo, Renee; Presby, Rose

2018-01-01

Operant behavior is not only regulated by factors related to the quality or quantity of reinforcement, but also by the work requirements inherent in performing instrumental actions. Moreover, organisms often make effort-related decisions involving economic choices such as cost/benefit analyses. Effort-based decision making is studied using behavioral procedures that offer choices between high-effort options leading to relatively preferred reinforcers vs. low effort/low reward choices. Several neural systems, including the mesolimbic dopamine (DA) system and other brain circuits, are involved in regulating effort-related aspects of motivation. Considerable evidence indicates that mesolimbic DA transmission exerts a bi-directional control over exertion of effort on instrumental behavior tasks. Interference with DA transmission produces a low-effort bias in animals tested on effort-based choice tasks, while increasing DA transmission with drugs such as DA transport blockers tends to enhance selection of high-effort options. The results from these pharmacology studies are corroborated by the findings from recent articles using optogenetic, chemogenetic and physiological techniques. In addition to providing important information about the neural regulation of motivated behavior, effort-based choice tasks are useful for developing animal models of some of the motivational symptoms that are seen in people with various psychiatric and neurological disorders (e.g., depression, schizophrenia, Parkinson’s disease). Studies of effort-based decision making may ultimately contribute to the development of novel drug treatments for motivational dysfunction. PMID:29628879

Dopamine, Effort-Based Choice, and Behavioral Economics: Basic and Translational Research.

PubMed

Salamone, John D; Correa, Merce; Yang, Jen-Hau; Rotolo, Renee; Presby, Rose

2018-01-01

Operant behavior is not only regulated by factors related to the quality or quantity of reinforcement, but also by the work requirements inherent in performing instrumental actions. Moreover, organisms often make effort-related decisions involving economic choices such as cost/benefit analyses. Effort-based decision making is studied using behavioral procedures that offer choices between high-effort options leading to relatively preferred reinforcers vs. low effort/low reward choices. Several neural systems, including the mesolimbic dopamine (DA) system and other brain circuits, are involved in regulating effort-related aspects of motivation. Considerable evidence indicates that mesolimbic DA transmission exerts a bi-directional control over exertion of effort on instrumental behavior tasks. Interference with DA transmission produces a low-effort bias in animals tested on effort-based choice tasks, while increasing DA transmission with drugs such as DA transport blockers tends to enhance selection of high-effort options. The results from these pharmacology studies are corroborated by the findings from recent articles using optogenetic, chemogenetic and physiological techniques. In addition to providing important information about the neural regulation of motivated behavior, effort-based choice tasks are useful for developing animal models of some of the motivational symptoms that are seen in people with various psychiatric and neurological disorders (e.g., depression, schizophrenia, Parkinson's disease). Studies of effort-based decision making may ultimately contribute to the development of novel drug treatments for motivational dysfunction.

Multi-Scale Distributed Representation for Deep Learning and its Application to b-Jet Tagging

NASA Astrophysics Data System (ADS)

Lee, Jason Sang Hun; Park, Inkyu; Park, Sangnam

2018-06-01

Recently machine learning algorithms based on deep layered artificial neural networks (DNNs) have been applied to a wide variety of high energy physics problems such as jet tagging or event classification. We explore a simple but effective preprocessing step which transforms each realvalued observational quantity or input feature into a binary number with a fixed number of digits. Each binary digit represents the quantity or magnitude in different scales. We have shown that this approach improves the performance of DNNs significantly for some specific tasks without any further complication in feature engineering. We apply this multi-scale distributed binary representation to deep learning on b-jet tagging using daughter particles' momenta and vertex information.

Concurrent development of facial identity and expression discrimination.

PubMed

Dalrymple, Kirsten A; Visconti di Oleggio Castello, Matteo; Elison, Jed T; Gobbini, M Ida

2017-01-01

Facial identity and facial expression processing both appear to follow a protracted developmental trajectory, yet these trajectories have been studied independently and have not been directly compared. Here we investigated whether these processes develop at the same or different rates using matched identity and expression discrimination tasks. The Identity task begins with a target face that is a morph between two identities (Identity A/Identity B). After a brief delay, the target face is replaced by two choice faces: 100% Identity A and 100% Identity B. Children 5-12-years-old were asked to pick the choice face that is most similar to the target identity. The Expression task is matched in format and difficulty to the Identity task, except the targets are morphs between two expressions (Angry/Happy, or Disgust/Surprise). The same children were asked to pick the choice face with the expression that is most similar to the target expression. There were significant effects of age, with performance improving (becoming more accurate and faster) on both tasks with increasing age. Accuracy and reaction times were not significantly different across tasks and there was no significant Age x Task interaction. Thus, facial identity and facial expression discrimination appear to develop at a similar rate, with comparable improvement on both tasks from age five to twelve. Because our tasks are so closely matched in format and difficulty, they may prove useful for testing face identity and face expression processing in special populations, such as autism or prosopagnosia, where one of these abilities might be impaired.

Testing Transitivity of Preferences on Two-Alternative Forced Choice Data

PubMed Central

Regenwetter, Michel; Dana, Jason; Davis-Stober, Clintin P.

2010-01-01

As Duncan Luce and other prominent scholars have pointed out on several occasions, testing algebraic models against empirical data raises difficult conceptual, mathematical, and statistical challenges. Empirical data often result from statistical sampling processes, whereas algebraic theories are nonprobabilistic. Many probabilistic specifications lead to statistical boundary problems and are subject to nontrivial order constrained statistical inference. The present paper discusses Luce's challenge for a particularly prominent axiom: Transitivity. The axiom of transitivity is a central component in many algebraic theories of preference and choice. We offer the currently most complete solution to the challenge in the case of transitivity of binary preference on the theory side and two-alternative forced choice on the empirical side, explicitly for up to five, and implicitly for up to seven, choice alternatives. We also discuss the relationship between our proposed solution and weak stochastic transitivity. We recommend to abandon the latter as a model of transitive individual preferences. PMID:21833217

The Effects of Study Tasks in a Computer-Based Chemistry Learning Environment

ERIC Educational Resources Information Center

Urhahne, Detlef; Nick, Sabine; Poepping, Anna Christin; Schulz , Sarah Jayne

2013-01-01

The present study examines the effects of different study tasks on the acquisition of knowledge about acids and bases in a computer-based learning environment. Three different task formats were selected to create three treatment conditions: learning with gap-fill and matching tasks, learning with multiple-choice tasks, and learning only from text…

EPIC Computational Models of Psychological Refractory-Period Effects in Human Multiple-Task Performance.

ERIC Educational Resources Information Center

Meyer, David E.; Kieras, David E.

Perceptual-motor and cognitive processes whereby people perform multiple concurrent tasks have been studied through an overlapping-tasks procedure in which two successive choice-reaction tasks are performed with a variable interval (stimulus onset asynchrony, or SOA) between the beginning of the first and second tasks. The increase in subjects'…

Simplest chronoscope. III. Further comparisons between reaction times obtained by meterstick versus machine.

PubMed

Montare, Alberto

2013-06-01

The three classical Donders' reaction time (RT) tasks (simple, choice, and discriminative RTs) were employed to compare reaction time scores from college students obtained by use of Montare's simplest chronoscope (meterstick) methodology to scores obtained by use of a digital-readout multi-choice reaction timer (machine). Five hypotheses were tested. Simple RT, choice RT, and discriminative RT were faster when obtained by meterstick than by machine. The meterstick method showed higher reliability than the machine method and was less variable. The meterstick method of the simplest chronoscope may help to alleviate the longstanding problems of low reliability and high variability of reaction time performances; while at the same time producing faster performance on Donders' simple, choice and discriminative RT tasks than the machine method.

Asymmetrically dominated choice problems, the isolation hypothesis and random incentive mechanisms.

PubMed

Cox, James C; Sadiraj, Vjollca; Schmidt, Ulrich

2014-01-01

This paper presents an experimental study of the random incentive mechanisms which are a standard procedure in economic and psychological experiments. Random incentive mechanisms have several advantages but are incentive-compatible only if responses to the single tasks are independent. This is true if either the independence axiom of expected utility theory or the isolation hypothesis of prospect theory holds. We present a simple test of this in the context of choice under risk. In the baseline (one task) treatment we observe risk behavior in a given choice problem. We show that by integrating a second, asymmetrically dominated choice problem in a random incentive mechanism risk behavior can be manipulated systematically. This implies that the isolation hypothesis is violated and the random incentive mechanism does not elicit true preferences in our example.

Investigating Proenvironmental Behavior: The Case of Commuting Mode Choice

NASA Astrophysics Data System (ADS)

Trinh, Tu Anh; Phuong Linh Le, Thi

2018-04-01

The central aim of this article is to investigate mode choice behavior among commuters in Ho Chi Minh City using disaggregate mode choice model and norm activation theory. A better understanding of commuters’ choice of transport mode provide an opportunity to obtain valuable information on their travel behaviors which help to build a basic for proffering solutions stimulating commuters to switch to public transport, which in turn contribute to deal with traffic problems and environmental issues. Binary logistic regression was employed under disaggregate choice method. Key findings indicated that Demographic factors including Age (-0.308), Married (-9.089), Weather (-8.272); Trip factors including Travel cost (0.437), Travel distance (0.252), and Norm activation theory (Awareness of consequences: AC2 (-1.699), AC4 (2.951), AC6 (-3.523), AC7 (-2.092), AC9 (-3.045), AC11 (+ 2.939), and Personal norms: PN2 (-2.695)) had strong impact on the commuters’ mode choice. Although motorcycle was the major transport mode among commuters, they presented their willingness to switch to bus transport if it had less negative impacts on the environment and their daily living environment.

Unconscious biases in task choices depend on conscious expectations.

PubMed

González-García, Carlos; Tudela, Pío; Ruz, María

2015-12-01

Recent studies highlight the influence of non-conscious information on task-set selection. However, it has not yet been tested whether this influence depends on conscious settings, as some theoretical models propose. In a series of three experiments, we explored whether non-conscious abstract cues could bias choices between a semantic and a perceptual task. In Experiment 1, we observed a non-conscious influence on task-set selection even when perceptual priming and cue-target compound confounds did not apply. Experiments 2 and 3 showed that, under restrictive conditions of visibility, cues only biased task selection when the conscious task-setting mindset led participants to search for information during the time period of the cue. However, this conscious strategy did not modulate the effect found when a subjective measure of consciousness was used. Altogether, our results show that the configuration of the conscious mindset determines the potential bias of non-conscious information on task-set selection. Copyright © 2015 Elsevier Inc. All rights reserved.

A Meta-Analysis Suggests Different Neural Correlates for Implicit and Explicit Learning.

PubMed

Loonis, Roman F; Brincat, Scott L; Antzoulatos, Evan G; Miller, Earl K

2017-10-11

A meta-analysis of non-human primates performing three different tasks (Object-Match, Category-Match, and Category-Saccade associations) revealed signatures of explicit and implicit learning. Performance improved equally following correct and error trials in the Match (explicit) tasks, but it improved more after correct trials in the Saccade (implicit) task, a signature of explicit versus implicit learning. Likewise, error-related negativity, a marker for error processing, was greater in the Match (explicit) tasks. All tasks showed an increase in alpha/beta (10-30 Hz) synchrony after correct choices. However, only the implicit task showed an increase in theta (3-7 Hz) synchrony after correct choices that decreased with learning. In contrast, in the explicit tasks, alpha/beta synchrony increased with learning and decreased thereafter. Our results suggest that explicit versus implicit learning engages different neural mechanisms that rely on different patterns of oscillatory synchrony. Copyright © 2017 Elsevier Inc. All rights reserved.

A Detection Pipeline for Galactic Binaries in LISA Data

NASA Technical Reports Server (NTRS)

Littenberg, Tyson B.

2012-01-01

The Galaxy is suspected to contain hundreds of millions of binary white dwarf systems, a large fraction of which will have sufficiently small orbital period to emit gravitational radiation in band for space-based gravitational wave detectors such as the Laser Interferometer Space Antenna (LISA). LISA's main science goal is the detection of cosmological events (supermassive black hole mergers) etc.) however the gravitational signal from the galaxy will be the dominant contribution to the data - including instrumental noise - over approximately two decades in frequency. The catalogue of detectable binary systems will serve as an unparalleled means of studying the Galaxy. Furthermore, to maximize the scientific return from the mission, the data must be "cleansed" of the galactic foreground. We will present an algorithm that can accurately resolve and subtract greater than or equal to 10000 of these sources from simulated data supplied by the Mock LISA Data Challenge Task Force. Using the time evolution of the gravitational wave frequency, we will reconstruct the position of the recovered binaries and show how LISA will sample the entire compact binary population in the Galaxy.

Medical image classification using spatial adjacent histogram based on adaptive local binary patterns.

PubMed

Liu, Dong; Wang, Shengsheng; Huang, Dezhi; Deng, Gang; Zeng, Fantao; Chen, Huiling

2016-05-01

Medical image recognition is an important task in both computer vision and computational biology. In the field of medical image classification, representing an image based on local binary patterns (LBP) descriptor has become popular. However, most existing LBP-based methods encode the binary patterns in a fixed neighborhood radius and ignore the spatial relationships among local patterns. The ignoring of the spatial relationships in the LBP will cause a poor performance in the process of capturing discriminative features for complex samples, such as medical images obtained by microscope. To address this problem, in this paper we propose a novel method to improve local binary patterns by assigning an adaptive neighborhood radius for each pixel. Based on these adaptive local binary patterns, we further propose a spatial adjacent histogram strategy to encode the micro-structures for image representation. An extensive set of evaluations are performed on four medical datasets which show that the proposed method significantly improves standard LBP and compares favorably with several other prevailing approaches. Copyright © 2016 Elsevier Ltd. All rights reserved.

Receptive fields selection for binary feature description.

PubMed

Fan, Bin; Kong, Qingqun; Trzcinski, Tomasz; Wang, Zhiheng; Pan, Chunhong; Fua, Pascal

2014-06-01

Feature description for local image patch is widely used in computer vision. While the conventional way to design local descriptor is based on expert experience and knowledge, learning-based methods for designing local descriptor become more and more popular because of their good performance and data-driven property. This paper proposes a novel data-driven method for designing binary feature descriptor, which we call receptive fields descriptor (RFD). Technically, RFD is constructed by thresholding responses of a set of receptive fields, which are selected from a large number of candidates according to their distinctiveness and correlations in a greedy way. Using two different kinds of receptive fields (namely rectangular pooling area and Gaussian pooling area) for selection, we obtain two binary descriptors RFDR and RFDG .accordingly. Image matching experiments on the well-known patch data set and Oxford data set demonstrate that RFD significantly outperforms the state-of-the-art binary descriptors, and is comparable with the best float-valued descriptors at a fraction of processing time. Finally, experiments on object recognition tasks confirm that both RFDR and RFDG successfully bridge the performance gap between binary descriptors and their floating-point competitors.

Age-Related Differences of Individuals’ Arithmetic Strategy Utilization with Different Level of Math Anxiety

PubMed Central

Si, Jiwei; Li, Hongxia; Sun, Yan; Xu, Yanli; Sun, Yu

2016-01-01

The present study used the choice/no-choice method to investigate the effect of math anxiety on the strategy used in computational estimation and mental arithmetic tasks and to examine age-related differences in this regard. Fifty-seven fourth graders, 56 sixth graders, and 60 adults were randomly selected to participate in the experiment. Results showed the following: (1) High-anxious individuals were more likely to use a rounding-down strategy in the computational estimation task under the best-choice condition. Additionally, sixth-grade students and adults performed faster than fourth-grade students on the strategy execution parameter. Math anxiety affected response times (RTs) and the accuracy with which strategies were executed. (2) The execution of the partial-decomposition strategy was superior to that of the full-decomposition strategy on the mental arithmetic task. Low-math-anxious persons provided more accurate answers than did high-math-anxious participants under the no-choice condition. This difference was significant for sixth graders. With regard to the strategy selection parameter, the RTs for strategy selection varied with age. PMID:27803685

Age-Related Differences of Individuals' Arithmetic Strategy Utilization with Different Level of Math Anxiety.

PubMed

Si, Jiwei; Li, Hongxia; Sun, Yan; Xu, Yanli; Sun, Yu

2016-01-01

The present study used the choice/no-choice method to investigate the effect of math anxiety on the strategy used in computational estimation and mental arithmetic tasks and to examine age-related differences in this regard. Fifty-seven fourth graders, 56 sixth graders, and 60 adults were randomly selected to participate in the experiment. Results showed the following: (1) High-anxious individuals were more likely to use a rounding-down strategy in the computational estimation task under the best-choice condition. Additionally, sixth-grade students and adults performed faster than fourth-grade students on the strategy execution parameter. Math anxiety affected response times (RTs) and the accuracy with which strategies were executed. (2) The execution of the partial-decomposition strategy was superior to that of the full-decomposition strategy on the mental arithmetic task. Low-math-anxious persons provided more accurate answers than did high-math-anxious participants under the no-choice condition. This difference was significant for sixth graders. With regard to the strategy selection parameter, the RTs for strategy selection varied with age.

Order information in verbal working memory shifts the subjective midpoint in both the line bisection and the landmark tasks.

PubMed

Antoine, Sophie; Ranzini, Mariagrazia; Gebuis, Titia; van Dijck, Jean-Philippe; Gevers, Wim

2017-10-01

A largely substantiated view in the domain of working memory is that the maintenance of serial order is achieved by generating associations of each item with an independent representation of its position, so-called position markers. Recent studies reported that the ordinal position of an item in verbal working memory interacts with spatial processing. This suggests that position markers might be spatial in nature. However, these interactions were so far observed in tasks implying a clear binary categorization of space (i.e., with left and right responses or targets). Such binary categorizations leave room for alternative interpretations, such as congruency between non-spatial categorical codes for ordinal position (e.g., begin and end) and spatial categorical codes for response (e.g., left and right). Here we discard this interpretation by providing evidence that this interaction can also be observed in a task that draws upon a continuous processing of space, the line bisection task. Specifically, bisections are modulated by ordinal position in verbal working memory, with lines bisected more towards the right after retrieving items from the end compared to the beginning of the memorized sequence. This supports the idea that position markers are intrinsically spatial in nature.

Assessing understanding of relative clauses: a comparison of multiple-choice comprehension versus sentence repetition.

PubMed

Frizelle, Pauline; O'Neill, Clodagh; Bishop, Dorothy V M

2017-11-01

Although sentence repetition is considered a reliable measure of children's grammatical knowledge, few studies have directly compared children's sentence repetition performance with their understanding of grammatical structures. The current study aimed to compare children's performance on these two assessment measures, using a multiple-choice picture-matching sentence comprehension task and a sentence repetition task. Thirty-three typically developing children completed both assessments, which included relative clauses representing a range of syntactic roles. Results revealed a similar order of difficulty of constructions on both measures but little agreement between them when evaluating individual differences. Interestingly, repetition was the easier of the two measures, with children showing the ability to repeat sentences they did not understand. This discrepancy is primarily attributed to the additional processing load resulting from the design of multiple-choice comprehension tasks, and highlights the fact that these assessments are invoking skills beyond those of linguistic competence.

Effects of Individual Differences in Working Memory on Plan Presentational Choices

PubMed Central

Tintarev, Nava; Masthoff, Judith

2016-01-01

This paper addresses research questions that are central to the area of visualization interfaces for decision support: (RQ1) whether individual user differences in working memory should be considered when choosing how to present visualizations; (RQ2) how to present the visualization to support effective decision making and processing; and (RQ3) how to evaluate the effectiveness of presentational choices. These questions are addressed in the context of presenting plans, or sequences of actions, to users. The experiments are conducted in several domains, and the findings are relevant to applications such as semi-autonomous systems in logistics. That is, scenarios that require the attention of humans who are likely to be interrupted, and require good performance but are not time critical. Following a literature review of different types of individual differences in users that have been found to affect the effectiveness of presentational choices, we consider specifically the influence of individuals' working memory (RQ1). The review also considers metrics used to evaluate presentational choices, and types of presentational choices considered. As for presentational choices (RQ2), we consider a number of variants including interactivity, aggregation, layout, and emphasis. Finally, to evaluate the effectiveness of plan presentational choices (RQ3) we adopt a layered-evaluation approach and measure performance in a dual task paradigm, involving both task interleaving and evaluation of situational awareness. This novel methodology for evaluating visualizations is employed in a series of experiments investigating presentational choices for a plan. A key finding is that emphasizing steps (by highlighting borders) can improve effectiveness on a primary task, but only when controlling for individual variation in working memory. PMID:27899905

Effects of Individual Differences in Working Memory on Plan Presentational Choices.

PubMed

Tintarev, Nava; Masthoff, Judith

2016-01-01

This paper addresses research questions that are central to the area of visualization interfaces for decision support: (RQ1) whether individual user differences in working memory should be considered when choosing how to present visualizations; (RQ2) how to present the visualization to support effective decision making and processing; and (RQ3) how to evaluate the effectiveness of presentational choices. These questions are addressed in the context of presenting plans, or sequences of actions, to users. The experiments are conducted in several domains, and the findings are relevant to applications such as semi-autonomous systems in logistics. That is, scenarios that require the attention of humans who are likely to be interrupted, and require good performance but are not time critical. Following a literature review of different types of individual differences in users that have been found to affect the effectiveness of presentational choices, we consider specifically the influence of individuals' working memory (RQ1). The review also considers metrics used to evaluate presentational choices, and types of presentational choices considered. As for presentational choices (RQ2), we consider a number of variants including interactivity, aggregation, layout, and emphasis. Finally, to evaluate the effectiveness of plan presentational choices (RQ3) we adopt a layered-evaluation approach and measure performance in a dual task paradigm, involving both task interleaving and evaluation of situational awareness. This novel methodology for evaluating visualizations is employed in a series of experiments investigating presentational choices for a plan. A key finding is that emphasizing steps (by highlighting borders) can improve effectiveness on a primary task, but only when controlling for individual variation in working memory.

Modafinil alters decision making based on feedback history - a randomized placebo-controlled double blind study in humans.

PubMed

Bellebaum, Christian; Kuchinke, Lars; Roser, Patrik

2017-02-01

Modafinil is becoming increasingly popular as a cognitive enhancer. Research on the effects of modafinil on cognitive function have yielded mixed results, with negative findings for simple memory and attention tasks and enhancing effects for more complex tasks. In the present study we examined whether modafinil, due to its known effect on the dopamine level in the striatum, alters feedback-related choice behaviour. We applied a task that separately tests the choice of previously rewarded behaviours (approach) and avoidance of previously punished behaviours. 18 participants received a single dose of 200 mg modafinil. Their performance was compared to a group of 22 participants who received placebo in a double-blind design. Modafinil but not placebo induced a significant bias towards approach behaviour as compared to the frequency of avoidance behaviour. General attention, overall feedback-based acquisition of choice behaviour and reaction times in high vs low conflict choices were not significantly affected by modafinil. This finding suggests that modafinil has a specific effect on dopamine-mediated choice behaviour based on the history of feedback, while a contribution of noradrenaline is also conceivable. The described change in decision making cannot be considered as cognitive enhancement, but might rather have detrimental effects on decisions in everyday life.

The pharmacology of effort-related choice behavior: Dopamine, depression, and individual differences.

PubMed

Salamone, John D; Correa, Merce; Yohn, Samantha; Lopez Cruz, Laura; San Miguel, Noemi; Alatorre, Luisa

2016-06-01

This review paper is focused upon the involvement of mesolimbic dopamine (DA) and related brain systems in effort-based processes. Interference with DA transmission affects instrumental behavior in a manner that interacts with the response requirements of the task, such that rats with impaired DA transmission show a heightened sensitivity to ratio requirements. Impaired DA transmission also affects effort-related choice behavior, which is assessed by tasks that offer a choice between a preferred reinforcer that has a high work requirement vs. less preferred reinforcer that can be obtained with minimal effort. Rats and mice with impaired DA transmission reallocate instrumental behavior away from food-reinforced tasks with high response costs, and show increased selection of low reinforcement/low cost options. Tests of effort-related choice have been developed into models of pathological symptoms of motivation that are seen in disorders such as depression and schizophrenia. These models are being employed to explore the effects of conditions associated with various psychopathologies, and to assess drugs for their potential utility as treatments for effort-related symptoms. Studies of the pharmacology of effort-based choice may contribute to the development of treatments for symptoms such as psychomotor slowing, fatigue or anergia, which are seen in depression and other disorders. Copyright © 2016 Elsevier B.V. All rights reserved.

More insight into the interplay of response selection and visual attention in dual-tasks: masked visual search and response selection are performed in parallel.

PubMed

Reimer, Christina B; Schubert, Torsten

2017-09-15

Both response selection and visual attention are limited in capacity. According to the central bottleneck model, the response selection processes of two tasks in a dual-task situation are performed sequentially. In conjunction search, visual attention is required to select the items and to bind their features (e.g., color and form), which results in a serial search process. Search time increases as items are added to the search display (i.e., set size effect). When the search display is masked, visual attention deployment is restricted to a brief period of time and target detection decreases as a function of set size. Here, we investigated whether response selection and visual attention (i.e., feature binding) rely on a common or on distinct capacity limitations. In four dual-task experiments, participants completed an auditory Task 1 and a conjunction search Task 2 that were presented with an experimentally modulated temporal interval between them (Stimulus Onset Asynchrony, SOA). In Experiment 1, Task 1 was a two-choice discrimination task and the conjunction search display was not masked. In Experiment 2, the response selection difficulty in Task 1 was increased to a four-choice discrimination and the search task was the same as in Experiment 1. We applied the locus-of-slack method in both experiments to analyze conjunction search time, that is, we compared the set size effects across SOAs. Similar set size effects across SOAs (i.e., additive effects of SOA and set size) would indicate sequential processing of response selection and visual attention. However, a significantly smaller set size effect at short SOA compared to long SOA (i.e., underadditive interaction of SOA and set size) would indicate parallel processing of response selection and visual attention. In both experiments, we found underadditive interactions of SOA and set size. In Experiments 3 and 4, the conjunction search display in Task 2 was masked. Task 1 was the same as in Experiments 1 and 2, respectively. In both experiments, the d' analysis revealed that response selection did not affect target detection. Overall, Experiments 1-4 indicated that neither the response selection difficulty in the auditory Task 1 (i.e., two-choice vs. four-choice) nor the type of presentation of the search display in Task 2 (i.e., not masked vs. masked) impaired parallel processing of response selection and conjunction search. We concluded that in general, response selection and visual attention (i.e., feature binding) rely on distinct capacity limitations.

The validation of procedures to assess prevocational task preferences in retarded adults.

PubMed

Mithaug, D E; Hanawalt, D A

1978-01-01

Three severely retarded young adults between the ages of 19 and 21 years participated in a prevocational training program, and worked regularly on six different tasks during the scheduled six-hour day. The study attempted to assess each subject's preferences for the six tasks: collating, stuffing, sorting, pulley assembly, flour-sifter assembly, and circuit-board stuffing. In Phase I, the procedure consisted of randomly pairing each task with all other tasks in a two-choice situation that required the subjects to select one task from each pair combination to work for a seven-minute period. The selection procedure consisted of presenting two representative task objects on a tray and requesting the subject to pick up one object and place it on the work table. The object selected represented the task worked for that period. The 15 possible pair combinations were presented randomly every two days for a period of 34 days to determine the preferences. During the validation phase (Phase II), each subject's least- and most-preferred tasks were paired separately with moderately-preferred tasks. As expected, these manipulations confirmed the baseline data, as choices for the moderately-preferred tasks decreased when consistently paired with the preferred tasks and increased when consistently paired with the least-preferred tasks.

Identifying instructional tasks that occasion problem behaviors and assessing the effects of student versus teacher choice among these tasks.

PubMed

Vaughn, B J; Horner, R H

1997-01-01

Levels of problem behavior were assessed when 4 students with severe disabilities received instruction on preferred versus nonpreferred tasks and when tasks of each type were chosen by the teacher rather than by the student. In Phase 1, interview and direct observation assessments were conducted to identify relative preferences for academic tasks. In Phase 2, the effects of these lower preference and higher preference tasks on the rate of problem behavior were evaluated using a multielement design. The results showed that lower preference tasks were associated with higher rates of problem behaviors and that students, when given a choice, consistently selected the tasks that had been identified through interview and direct observation as higher preference. In Phase 3, we assessed whether allowing the students to choose between pairs of lower preference tasks or between pairs of higher preference tasks reduced problem behavior relative to a condition in which the teacher selected the same tasks. For 2 of 4 students, the rates of problem behavior were lower when students (rather than the teacher) selected the lower preference activity. Higher preference tasks for 3 students were associated with relatively low rates of problem behavior regardless of whether the student or the teacher selected the task.

Neural antecedents of social decision-making in a partner choice task.

PubMed

Cartmell, Samuel C D; Chun, Marvin M; Vickery, Timothy J

2014-11-01

Experiments in financial decision-making point to two complementary processes that encode prospective gain and loss preceding the choice to purchase consumer goods. These processes involve the nucleus accumbens (NAcc) and the right anterior insula, respectively. The current experiment used functional MRI to investigate whether these regions served a similar function during an analogous social decision-making task without the influence of monetary outcomes. In this task, subjects chose partners based on face stimuli of varying attractiveness (operationalizing value) and ratings of compatibility with the participant (operationalizing likelihood of rejection). The NAcc responded to anticipated gain; the right anterior insula responded to compatibility, but not in a manner that suggests an analogy to anticipated cost. Logistic regression modeling demonstrated that both regions predicted subsequent choice above and beyond the influence of group attractiveness ratings or compatibility alone. Although the function of the insula may differ between tasks, these results suggest that financial and social decision-making recruit a similar network of brain regions. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Parameter Estimation for Compact Binaries with Ground-Based Gravitational-Wave Observations Using the LALInference

NASA Technical Reports Server (NTRS)

Veitch, J.; Raymond, V.; Farr, B.; Farr, W.; Graff, P.; Vitale, S.; Aylott, B.; Blackburn, K.; Christensen, N.; Coughlin, M.

2015-01-01

The Advanced LIGO and Advanced Virgo gravitational wave (GW) detectors will begin operation in the coming years, with compact binary coalescence events a likely source for the first detections. The gravitational waveforms emitted directly encode information about the sources, including the masses and spins of the compact objects. Recovering the physical parameters of the sources from the GW observations is a key analysis task. This work describes the LALInference software library for Bayesian parameter estimation of compact binary signals, which builds on several previous methods to provide a well-tested toolkit which has already been used for several studies. We show that our implementation is able to correctly recover the parameters of compact binary signals from simulated data from the advanced GW detectors. We demonstrate this with a detailed comparison on three compact binary systems: a binary neutron star (BNS), a neutron star - black hole binary (NSBH) and a binary black hole (BBH), where we show a cross-comparison of results obtained using three independent sampling algorithms. These systems were analysed with non-spinning, aligned spin and generic spin configurations respectively, showing that consistent results can be obtained even with the full 15-dimensional parameter space of the generic spin configurations. We also demonstrate statistically that the Bayesian credible intervals we recover correspond to frequentist confidence intervals under correct prior assumptions by analysing a set of 100 signals drawn from the prior. We discuss the computational cost of these algorithms, and describe the general and problem-specific sampling techniques we have used to improve the efficiency of sampling the compact binary coalescence (CBC) parameter space.

Applying local binary patterns in image clustering problems

NASA Astrophysics Data System (ADS)

Skorokhod, Nikolai N.; Elizarov, Alexey I.

2017-11-01

Due to the fact that the cloudiness plays a critical role in the Earth radiative balance, the study of the distribution of different types of clouds and their movements is relevant. The main sources of such information are artificial satellites that provide data in the form of images. The most commonly used method of solving tasks of processing and classification of images of clouds is based on the description of texture features. The use of a set of local binary patterns is proposed to describe the texture image.

Connections between Secondary Mathematics Teachers' Beliefs and Their Selection of Tasks for English Language Learners

ERIC Educational Resources Information Center

de Araujo, Zandra

2017-01-01

The tasks teachers select impact students' opportunities to learn mathematics and teachers' beliefs influence their choice of tasks. Through the qualitative analysis of surveys, interviews and classroom artefacts from three secondary mathematics teachers, this study examined teachers' selection of mathematics tasks for English language learners…

Development of "Task Value" Instrument for Biology as a School Subject

ERIC Educational Resources Information Center

Köksal, Mustafa Serdar; Yaman, Süleyman

2013-01-01

The expectancy-value model of motivation states that individuals' choice, persistence and performances are related to their beliefs about how much they value task. Despite the importance of "task value" in learning biology, lack of the instruments on task value for high school biology courses for practical use indicated requirement to…

Feedback is the breakfast of champions: the significance of self-controlled formal feedback for autonomous task engagement.

PubMed

Meng, Liang; Yang, Zijing

2018-01-03

With the aim of examining the positive effect of the formal feedback mechanism itself beyond its informational aspect, we engaged participants in the stopwatch task and recorded their electroencephalogram throughout the experiment. This task requires a button press to stop the watch within a given time interval, the completion of which is simultaneously accompanied by adequate information on task performance. In the self-controlled feedback mode, participants could freely choose whether to request formal feedback after completing the task. In another mode, additional feedback was not provided. The 'non-choice' cue was found to elicit a more negative cue-elicited feedback negativity compared with 'choice', suggesting that the opportunity to solicit formal feedback was perceived as more desirable. In addition, a more enhanced stimulus-preceding negativity was observed prior to the task initiation cue in the self-controlled feedback condition, indicating that participants paid more sustained anticipatory attention during task preparation. Taken together, these electrophysiological results suggested an inherent reward within the formal feedback mechanism itself and the significance of self-controlled formal feedback for autonomous task engagement.

Individual Differences in Risk Preference Predict Neural Responses during Financial Decision-Making

PubMed Central

Engelmann, Jan B.; Tamir, Diana

2009-01-01

We investigated the neural correlates of subjective valuations during a task involving risky choices about lotteries. Because expected value was held constant across all lotteries, decisions were influenced by subjective preferences, which manifest behaviorally as risk-seeking or risk-averse attitudes. To isolate structures encoding risk preference during choice, we probed for areas showing increased activation as a function of selected risk-level. Such response patterns were obtained in anterior (ACC) and posterior cingulate cortex (PCC), superior frontal gyrus, caudate nucleus, and substantia nigra. Behavioral results revealed the presence of risk-averse and risk-neutral individuals. In parallel, brain signals revealed modulation of activity by risk-attitude during choice. Correlations between risk-seeking attitudes and neural activity during risky choice were obtained in superior and inferior frontal gyri, medial and lateral orbitofrontal cortex, and parahippocampal gyrus, while correlations with risk-averse attitudes were found in the caudate. The dynamics of neural responses relevant to each stage of the task (decision, anticipation, outcome) were investigated via timeseries and conjunction analyses. Though the networks engaged in each of the task stages were mostly distinct, regions of ACC, PCC and caudate were consistently activated during each decision-making phase. These results demonstrate (1) that subjective assessments of risk, as well as individual attitudes toward risk, play a significant role in modulating activity within brain regions recruited during decision-making, and (2) that ACC, PCC and caudate are relevant during each phase of a decision-making task requiring subjective valuations, strengthening the role of these regions in self-referential subjective valuations during choice. PMID:19576868

Variability of human corticospinal excitability tracks the state of action preparation.

PubMed

Klein-Flügge, Miriam C; Nobbs, David; Pitcher, Julia B; Bestmann, Sven

2013-03-27

Task-evoked trial-by-trial variability is a ubiquitous property of neural responses, yet its functional role remains largely unclear. Recent work in nonhuman primates shows that the temporal structure of neural variability in several brain regions is task-related. For example, trial-by-trial variability in premotor cortex tracks motor preparation with increasingly consistent firing rates and thus a decline in variability before movement onset. However, whether noninvasive measures of the variability of population activity available from humans can similarly track the preparation of actions remains unknown. We tested this by using single-pulse transcranial magnetic stimulation (TMS) over primary motor cortex (M1) to measure corticospinal excitability (CSE) at different times during action preparation. First, we established the basic properties of intrinsic CSE variability at rest. Then, during the task, responses (left or right button presses) were either directly instructed (forced choice) or resulted from a value decision (choice). Before movement onset, we observed a temporally specific task-related decline in CSE variability contralateral to the responding hand. This decline was stronger in fast-response compared with slow-response trials, consistent with data in nonhuman primates. For the nonresponding hand, CSE variability also decreased, but only in choice trials, and earlier compared with the responding hand, possibly reflecting choice-specific suppression of unselected actions. These findings suggest that human CSE variability measured by TMS over M1 tracks the state of motor preparation, and may reflect the optimization of preparatory population activity. This provides novel avenues in humans to assess the dynamics of action preparation but also more complex processes, such as choice-to-action transformations.

Exploring the Impact of the Informational Value of Feedback Choices on Performance Outcomes in an Online Assessment Game

ERIC Educational Resources Information Center

Cutumisu, Maria

2017-01-01

This paper examines the impact of the informational value of feedback choices on students' performance, their choice to revise, and the time they spend designing posters and reading feedback in an assessment game. Choices to seek confirmatory or critical feedback and to revise posters in a poster design task were collected from a hundred and six…

Sex and Age Differences in Target Choice on an Aggressive Task.

ERIC Educational Resources Information Center

Campbell, James N.; Nadelman, Lorraine

The role of inhibition as related to sex differences in aggression was investigated using 20 nursery school and 20 second grade children. A dart gun was employed, with choices of four targets--drawings of a boy, a girl, a zebra, and an object. There were three sessions and eight target choices per session. Choice of the human target was assumed to…

Impaired Decision Making and Loss of Inhibitory-Control in a Rat Model of Huntington Disease

PubMed Central

El Massioui, Nicole; Lamirault, Charlotte; Yagüe, Sara; Adjeroud, Najia; Garces, Daniel; Maillard, Alexis; Tallot, Lucille; Yu-Taeger, Libo; Riess, Olaf; Allain, Philippe; Nguyen, Huu Phuc; von Hörsten, Stephan; Doyère, Valérie

2016-01-01

Cognitive deficits associated with Huntington disease (HD) are generally dominated by executive function disorders often associated with disinhibition and impulsivity/compulsivity. Few studies have directly examined symptoms and consequences of behavioral disinhibition in HD and its relation with decision-making. To assess the different forms of impulsivity in a transgenic model of HD (tgHD rats), two tasks assessing cognitive/choice impulsivity were used: risky decision-making with a rat gambling task (RGT) and intertemporal choices with a delay discounting task (DD). To assess waiting or action impulsivity the differential reinforcement of low rate of responding task (DRL) was used. In parallel, the volume as well as cellular activity of the amygdala was analyzed. In contrast to WT rats, 15 months old tgHD rats exhibited a poor efficiency in the RGT task with difficulties to choose advantageous options, a steep DD curve as delays increased in the DD task and a high rate of premature and bursts responses in the DRL task. tgHD rats also demonstrated a concomitant and correlated presence of both action and cognitive/choice impulsivity in contrast to wild type (WT) animals. Moreover, a reduced volume associated with an increased basal cellular activity of the central nucleus of amygdala indicated a dysfunctional amygdala in tgHD rats, which could underlie inhibitory dyscontrol. In conclusion, tgHD rats are a good model for impulsivity disorder that could be used more widely to identify potential pharmacotherapies to treat these invasive symptoms in HD. PMID:27833538

Reward Contrast Effects on Impulsive Choice and Timing in Rats

PubMed Central

Smith, Aaron P.; Peterson, Jennifer R.; Kirkpatrick, Kimberly

2016-01-01

Despite considerable interest in impulsive choice as a predictor of a variety of maladaptive behaviors, the mechanisms that drive choice behavior are still poorly understood. The present study sought to examine the influence of one understudied variable, reward magnitude contrast, on choice and timing behavior as changes in magnitude commonly occur within choice procedures. In addition, assessments of indirect effects on choice behavior through magnitude-timing interactions were assessed by measuring timing within the choice task. Rats were exposed to choice procedures composed of different pairs of magnitudes of rewards for either the smaller-sooner (SS) or larger-later (LL) option. In Phase 2, the magnitude of reward either increased or decreased by 1 pellet in different groups (LL increase = 1v1→1v2; SS decrease = 2v2 → 1v2; SS increase = 1v2 → 2v2), followed by a return to baseline in Phase 3. Choice behavior was affected by the initial magnitudes experienced in the task, demonstrating a strong anchor effect. The nature of the change in magnitude affected choice behavior as well. Timing behavior was also affected by the reward contrast manipulation albeit to a lesser degree and the timing and choice effects were correlated. The results suggest that models of choice behavior should incorporate reinforcement history, reward contrast elements, and magnitude-timing interactions, but that direct effects of reward contrast on choice should be given more weight than the indirect reward-timing interactions. A better understanding of the factors that contribute to choice behavior could supply key insights into this important individual differences variable. PMID:27867839

Empirical study of seven data mining algorithms on different characteristics of datasets for biomedical classification applications.

PubMed

Zhang, Yiyan; Xin, Yi; Li, Qin; Ma, Jianshe; Li, Shuai; Lv, Xiaodan; Lv, Weiqi

2017-11-02

Various kinds of data mining algorithms are continuously raised with the development of related disciplines. The applicable scopes and their performances of these algorithms are different. Hence, finding a suitable algorithm for a dataset is becoming an important emphasis for biomedical researchers to solve practical problems promptly. In this paper, seven kinds of sophisticated active algorithms, namely, C4.5, support vector machine, AdaBoost, k-nearest neighbor, naïve Bayes, random forest, and logistic regression, were selected as the research objects. The seven algorithms were applied to the 12 top-click UCI public datasets with the task of classification, and their performances were compared through induction and analysis. The sample size, number of attributes, number of missing values, and the sample size of each class, correlation coefficients between variables, class entropy of task variable, and the ratio of the sample size of the largest class to the least class were calculated to character the 12 research datasets. The two ensemble algorithms reach high accuracy of classification on most datasets. Moreover, random forest performs better than AdaBoost on the unbalanced dataset of the multi-class task. Simple algorithms, such as the naïve Bayes and logistic regression model are suitable for a small dataset with high correlation between the task and other non-task attribute variables. K-nearest neighbor and C4.5 decision tree algorithms perform well on binary- and multi-class task datasets. Support vector machine is more adept on the balanced small dataset of the binary-class task. No algorithm can maintain the best performance in all datasets. The applicability of the seven data mining algorithms on the datasets with different characteristics was summarized to provide a reference for biomedical researchers or beginners in different fields.

The neural substrates of deliberative decision making: contrasting effects of hippocampus lesions on performance and vicarious trial-and-error behavior in a spatial memory task and a visual discrimination task

PubMed Central

Bett, David; Allison, Elizabeth; Murdoch, Lauren H.; Kaefer, Karola; Wood, Emma R.; Dudchenko, Paul A.

2012-01-01

Vicarious trial-and-errors (VTEs) are back-and-forth movements of the head exhibited by rodents and other animals when faced with a decision. These behaviors have recently been associated with prospective sweeps of hippocampal place cell firing, and thus may reflect a rodent model of deliberative decision-making. The aim of the current study was to test whether the hippocampus is essential for VTEs in a spatial memory task and in a simple visual discrimination (VD) task. We found that lesions of the hippocampus with ibotenic acid produced a significant impairment in the accuracy of choices in a serial spatial reversal (SR) task. In terms of VTEs, whereas sham-lesioned animals engaged in more VTE behavior prior to identifying the location of the reward as opposed to repeated trials after it had been located, the lesioned animals failed to show this difference. In contrast, damage to the hippocampus had no effect on acquisition of a VD or on the VTEs seen in this task. For both lesion and sham-lesion animals, adding an additional choice to the VD increased the number of VTEs and decreased the accuracy of choices. Together, these results suggest that the hippocampus may be specifically involved in VTE behavior during spatial decision making. PMID:23115549

The effects of response cost and species-typical behaviors on a daily time-place learning task.

PubMed

Deibel, Scott H; Thorpe, Christina M

2013-03-01

Two theories that have been hypothesized to mediate acquisition in daily time-place learning (TPL) tasks were investigated in a free operant daily TPL task: the response cost hypothesis and the species-typical behavior hypothesis. One lever at the end of one of the choice arms of a T-maze provided food in the morning, and 6 h later, a lever in the other choice arm provided food. Four groups were used to assess the effect of two possible sources of response cost: physical effort of the task and costs associated with foraging ecology. One group was used to assess the effect of explicitly allowing for species-typical behaviors. If only first arm choice data were considered, there was little evidence of learning. However, both first press and percentage of presses on the correct lever prior to the first reinforcement revealed evidence of TPL in most rats tested. Unexpectedly, the high response cost groups for both of the proposed sources did not perform better than the low response cost groups. The groups that allowed animals to display species-typical behaviors performed the worst. Skip session probe trials confirmed that the majority of the rats that acquired the task were using a circadian timing strategy. The results from the present study suggest that learning in free operant daily TPL tasks might not be dependent on response cost.

"Heads or Tails?"--A Reachability Bias in Binary Choice

ERIC Educational Resources Information Center

Bar-Hillel, Maya; Peer, Eyal; Acquisti, Alessandro

2014-01-01

When asked to mentally simulate coin tosses, people generate sequences that differ systematically from those generated by fair coins. It has been rarely noted that this divergence is apparent already in the very 1st mental toss. Analysis of several existing data sets reveals that about 80% of respondents start their sequence with Heads. We…

How Do Substitute Teachers Substitute? An Empirical Study of Substitute-Teacher Labor Supply

ERIC Educational Resources Information Center

Gershenson, Seth

2012-01-01

This paper examines the daily labor supply of a potentially important, but often overlooked, source of instruction in U.S. public schools: substitute teachers. I estimate a sequential binary-choice model of substitute teachers' job-offer acceptance decisions using data on job offers made by a randomized automated calling system. Importantly, this…

Thermodynamic evaluation of mass diffusion in ionic mixtures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kagan, Grigory; Tang, Xian-Zhu

2014-02-15

The thermodynamic technique of Landau and Lifshitz originally developed for inter-species diffusion in a binary neutral gas mixture is extended to a quasi-neutral plasma with two ion species. It is shown that, while baro- and electro-diffusion coefficients depend on the choice of the thermodynamic system, prediction for the total diffusive mass flux is invariant.

Rapid Acquisition in Concurrent Chains: Evidence for a Decision Model

ERIC Educational Resources Information Center

Grace, Randolph C.; McLean, Anthony P.

2006-01-01

Pigeons' choice in concurrent chains can adapt to rapidly changing contingencies. Grace, Bragason, and McLean (2003) found that relative initial-link response rate was sensitive to the immediacy ratio in the current session when one of the terminal-link fixed-interval schedules was changed daily according to a pseudorandom binary sequence (e.g.,…

Understanding the Varying Investments in Researcher and Teacher Development and Enhancement: Implications for Academic Developers

ERIC Educational Resources Information Center

Petrova, Petia; Hadjianastasis, Marios

2015-01-01

The increasing disparity between the research and teaching aspects of academic careers has been an area of concern in different national contexts over a number of decades. Anyone working with educational enhancement will have encountered the binary choice between research development and educational enhancement that academics are forced to make,…

Paired comparison estimates of willingness to accept versus contingent valuation estimates of willingness to pay

Treesearch

John B. Loomis; George Peterson; Patricia A. Champ; Thomas C. Brown; Beatrice Lucero

1998-01-01

Estimating empirical measures of an individual's willingness to accept that are consistent with conventional economic theory, has proven difficult. The method of paired comparison offers a promising approach to estimate willingness to accept. This method involves having individuals make binary choices between receiving a particular good or a sum of money....

The effects of task difficulty, novelty and the size of the search space on intrinsically motivated exploration.

PubMed

Baranes, Adrien F; Oudeyer, Pierre-Yves; Gottlieb, Jacqueline

2014-01-01

Devising efficient strategies for exploration in large open-ended spaces is one of the most difficult computational problems of intelligent organisms. Because the available rewards are ambiguous or unknown during the exploratory phase, subjects must act in intrinsically motivated fashion. However, a vast majority of behavioral and neural studies to date have focused on decision making in reward-based tasks, and the rules guiding intrinsically motivated exploration remain largely unknown. To examine this question we developed a paradigm for systematically testing the choices of human observers in a free play context. Adult subjects played a series of short computer games of variable difficulty, and freely choose which game they wished to sample without external guidance or physical rewards. Subjects performed the task in three distinct conditions where they sampled from a small or a large choice set (7 vs. 64 possible levels of difficulty), and where they did or did not have the possibility to sample new games at a constant level of difficulty. We show that despite the absence of external constraints, the subjects spontaneously adopted a structured exploration strategy whereby they (1) started with easier games and progressed to more difficult games, (2) sampled the entire choice set including extremely difficult games that could not be learnt, (3) repeated moderately and high difficulty games much more frequently than was predicted by chance, and (4) had higher repetition rates and chose higher speeds if they could generate new sequences at a constant level of difficulty. The results suggest that intrinsically motivated exploration is shaped by several factors including task difficulty, novelty and the size of the choice set, and these come into play to serve two internal goals-maximize the subjects' knowledge of the available tasks (exploring the limits of the task set), and maximize their competence (performance and skills) across the task set.

The Impact of a Sports Vision Training Program in Youth Field Hockey Players

PubMed Central

Schwab, Sebastian; Memmert, Daniel

2012-01-01

The aim of this study was to investigate whether a sports vision training program improves the visual performance of youth male field hockey players, ages 12 to 16 years, after an intervention of six weeks compared to a control group with no specific sports vision training. The choice reaction time task at the D2 board (Learning Task I), the functional field of view task (Learning Task II) and the multiple object tracking (MOT) task (Transfer Task) were assessed before and after the intervention and again six weeks after the second test. Analyzes showed significant differences between the two groups for the choice reaction time task at the D2 board and the functional field of view task, with significant improvements for the intervention group and none for the control group. For the transfer task, we could not find statistically significant improvements for either group. The results of this study are discussed in terms of theoretical and practical implications. Key pointsPerceptual training with youth field hockey playersCan a sports vision training program improve the visual performance of youth male field hockey players, ages 12 to 16 years, after an intervention of six weeks compared to a control group with no specific sports vision training?The intervention was performed in the “VisuLab” as DynamicEye® SportsVision Training at the German Sport University Cologne.We ran a series of 3 two-factor univariate analysis of variance (ANOVA) with repeated measures on both within subject independent variables (group; measuring point) to examine the effects on central perception, peripheral perception and choice reaction time.The present study shows an improvement of certain visual abilities with the help of the sports vision training program. PMID:24150071

Relationship between Attitude towards Technical Education and Academic Achievement in Mathematics and Science of the First and Second Year High School Students, Caritas Don Bosco School, SY 2002-2003

ERIC Educational Resources Information Center

Magno, Carlo

2003-01-01

Background: This study made use of the "Model of Academic Choice" by Meece et al. (1982). It is a general model of academic choice, expectation and value of attitude leading to achievement. The model links achievement with constructs of expectation of success on a task and the subjective value of the task influencing the attitude of…

Dopaminergic lesions of the dorsolateral striatum in rats increase delay discounting in an impulsive choice task.

PubMed

Tedford, Stephanie E; Persons, Amanda L; Napier, T Celeste

2015-01-01

Dysregulated dopamine transmission in striatal circuitry is associated with impulsivity. The current study evaluated the influence of dopaminergic inputs to the dorsolateral striatum on impulsive choice, one aspect of impulsive behavior. We implemented an operant task that measures impulsive choice in rats via delay discounting wherein intracranial self-stimulation (ICSS) was used as the positive reinforcer. To do so, rats were anesthetized to allow implanting of a stimulating electrode within the lateral hypothalamus of one hemisphere and bilateral dorsal striatal injections of the dopaminergic toxin, 6-OHDA (lesioned) or its vehicle (sham). Following recovery, rats were trained in a delay discounting task wherein they selected between a small ICSS current presented immediately after lever pressing, and a large ICSS current presented following a 0 to 15 s delay upon pressing the alternate lever. Task acquisition and reinforcer discrimination were similar for lesioned and sham rats. All rats exhibited an initial preference for the large reinforcer, and as the delay was increased, preference for the large reinforcer was decreased indicating that the subjective value of the large reinforcer was discounted as a function of delay time. However, this discounting effect was significantly enhanced in lesioned rats for the longer delays. These data reveal a contribution of dopaminergic inputs to the dorsolateral striatum on impulsive choice behavior, and provide new insights into neural substrates underlying discounting behaviors.

Dopaminergic Lesions of the Dorsolateral Striatum in Rats Increase Delay Discounting in an Impulsive Choice Task

PubMed Central

Tedford, Stephanie E.; Persons, Amanda L.; Napier, T. Celeste

2015-01-01

Dysregulated dopamine transmission in striatal circuitry is associated with impulsivity. The current study evaluated the influence of dopaminergic inputs to the dorsolateral striatum on impulsive choice, one aspect of impulsive behavior. We implemented an operant task that measures impulsive choice in rats via delay discounting wherein intracranial self-stimulation (ICSS) was used as the positive reinforcer. To do so, rats were anesthetized to allow implanting of a stimulating electrode within the lateral hypothalamus of one hemisphere and bilateral dorsal striatal injections of the dopaminergic toxin, 6-OHDA (lesioned) or its vehicle (sham). Following recovery, rats were trained in a delay discounting task wherein they selected between a small ICSS current presented immediately after lever pressing, and a large ICSS current presented following a 0 to 15s delay upon pressing the alternate lever. Task acquisition and reinforcer discrimination were similar for lesioned and sham rats. All rats exhibited an initial preference for the large reinforcer, and as the delay was increased, preference for the large reinforcer was decreased indicating that the subjective value of the large reinforcer was discounted as a function of delay time. However, this discounting effect was significantly enhanced in lesioned rats for the longer delays. These data reveal a contribution of dopaminergic inputs to the dorsolateral striatum on impulsive choice behavior, and provide new insights into neural substrates underlying discounting behaviors. PMID:25927685

Preference on cash-choice task predicts externalizing outcomes in 17-year-olds.

PubMed

Sparks, Jordan C; Isen, Joshua D; Iacono, William G

2014-03-01

Delay-discounting, the tendency to prefer a smaller-sooner reward to a larger-later reward, has been associated with a range of externalizing behaviors. Laboratory delay-discounting tasks have emerged as a useful measure to index impulsivity and a proclivity towards externalizing pyschopathology. While many studies demonstrate the existence of a latent externalizing factor that is heritable, there have been few genetic studies of delay-discounting. Further, the increased vulnerability for risky behavior in adolescence makes adolescent samples an attractive target for future research, and expeditious, ecologically-valid delay-discounting measures are helpful in this regard. The primary goal of this study was to help validate the utility of a "cash-choice" measure for use in a sample of older adolescents. We used a sample of 17-year-old twins (n = 791) from the Minnesota Twin Family Enrichment study. Individuals who chose the smaller-sooner reward were more likely to have used a range of addictive substances, engaged in sexual intercourse, and earned lower GPAs. Best fitting biometric models from univariate analyses supported the heritability of cash-choice and externalizing, but bivariate modeling results indicated that the correlation between cash-choice and externalizing was determined largely by shared environmental influences, thus failing to support cash-choice as a possible endophenotype for externalizing in this age group. Our findings lend further support to the utility of cash-choice as a measure of individual differences in decision making and suggest that, by late adolescence, this task indexes shared environmental risk for externalizing behavior.

Prefrontal spatial working memory network predicts animal's decision making in a free choice saccade task

PubMed Central

Mochizuki, Kei

2015-01-01

While neurons in the lateral prefrontal cortex (PFC) encode spatial information during the performance of working memory tasks, they are also known to participate in subjective behavior such as spatial attention and action selection. In the present study, we analyzed the activity of primate PFC neurons during the performance of a free choice memory-guided saccade task in which the monkeys needed to choose a saccade direction by themselves. In trials when the receptive field location was subsequently chosen by the animal, PFC neurons with spatially selective visual response started to show greater activation before cue onset. This result suggests that the fluctuation of firing before cue presentation prematurely biased the representation of a certain spatial location and eventually encouraged the subsequent choice of that location. In addition, modulation of the activity by the animal's choice was observed only in neurons with high sustainability of activation and was also dependent on the spatial configuration of the visual cues. These findings were consistent with known characteristics of PFC neurons in information maintenance in spatial working memory function. These results suggest that precue fluctuation of spatial representation was shared and enhanced through the working memory network in the PFC and could finally influence the animal's free choice of saccade direction. The present study revealed that the PFC plays an important role in decision making in a free choice condition and that the dynamics of decision making are constrained by the network architecture embedded in this cortical area. PMID:26490287

Learning the opportunity cost of time in a patch-foraging task

PubMed Central

Constantino, Sara; Daw, Nathaniel D.

2015-01-01

Although most decision research concerns choice between simultaneously presented options, in many situations options are encountered serially and the decision is whether to exploit an option or search for a better one. Such problems have a rich history in animal foraging but we know little about the psychological processes involved. In particular, it is unknown whether learning in these problems is supported by the well studied neurocomputational mechanisms involved in more conventional tasks. We investigated how humans learn in a foraging task, which requires deciding whether to harvest a depleting resource or switch to a replenished one. The optimal choice (given by the Marginal Value Theorem; MVT) requires comparing the immediate return from harvesting to the opportunity cost of time, which is given by the long-run average reward. In two experiments, we varied opportunity cost across blocks. Subjects adjusted their behavior to blockwise changes in environmental characteristics. We examined how subjects learned their choice strategies by comparing choice adjustments to a learning rule suggested by the MVT (where the opportunity cost threshold is estimated as an average over previous rewards) and to the predominant incremental learning theory in neuroscience, temporal-difference learning (TD). Trial-by-trial decisions were better explained by the MVT threshold learning rule. These findings expand on the foraging literature, which has focused on steady-state behavior, by elucidating a computational mechanism for learning in switching tasks that is distinct from those used in traditional tasks, and suggest connections to research on average reward rates in other domains of neuroscience. PMID:25917000

Under what conditions is recognition spared relative to recall after selective hippocampal damage in humans?

PubMed

Holdstock, J S; Mayes, A R; Roberts, N; Cezayirli, E; Isaac, C L; O'Reilly, R C; Norman, K A

2002-01-01

The claim that recognition memory is spared relative to recall after focal hippocampal damage has been disputed in the literature. We examined this claim by investigating object and object-location recall and recognition memory in a patient, YR, who has adult-onset selective hippocampal damage. Our aim was to identify the conditions under which recognition was spared relative to recall in this patient. She showed unimpaired forced-choice object recognition but clearly impaired recall, even when her control subjects found the object recognition task to be numerically harder than the object recall task. However, on two other recognition tests, YR's performance was not relatively spared. First, she was clearly impaired at an equivalently difficult yes/no object recognition task, but only when targets and foils were very similar. Second, YR was clearly impaired at forced-choice recognition of object-location associations. This impairment was also unrelated to difficulty because this task was no more difficult than the forced-choice object recognition task for control subjects. The clear impairment of yes/no, but not of forced-choice, object recognition after focal hippocampal damage, when targets and foils are very similar, is predicted by the neural network-based Complementary Learning Systems model of recognition. This model postulates that recognition is mediated by hippocampally dependent recollection and cortically dependent familiarity; thus hippocampal damage should not impair item familiarity. The model postulates that familiarity is ineffective when very similar targets and foils are shown one at a time and subjects have to identify which items are old (yes/no recognition). In contrast, familiarity is effective in discriminating which of similar targets and foils, seen together, is old (forced-choice recognition). Independent evidence from the remember/know procedure also indicates that YR's familiarity is normal. The Complementary Learning Systems model can also accommodate the clear impairment of forced-choice object-location recognition memory if it incorporates the view that the most complete convergence of spatial and object information, represented in different cortical regions, occurs in the hippocampus.

Making Decisions about Now and Later: Development of Future-Oriented Self-Control

ERIC Educational Resources Information Center

Garon, Nancy M.; Longard, Julie; Bryson, Susan E.; Moore, Chris

2012-01-01

This study explored factors underlying preschoolers' ability to make future-oriented choices. In a delay-of-gratification choice task, quantity and visibility of the reward was systematically varied. Participants included 90 typically developing children aged 2-4 years. Children made more choices to delay gratification as the quantity of the…

Career-Choice Readiness in Adolescence: Developmental Trajectories and Individual Differences

ERIC Educational Resources Information Center

Hirschi, Andreas

2011-01-01

Developing career-choice readiness is an important task in adolescence, but current theory and research has provided a rather static view of the phenomenon. The present study investigated the development of career-choice readiness among a group of 325 Swiss students assessed four times every 5 months from seventh through eighth grade. A…

Effects of Picture Activity Schedules on Tasks Completed

ERIC Educational Resources Information Center

Morrisett, Michael Eric

2015-01-01

Self-determination is the freedom to make choices that impact an individual's life. Many people would agree that self-determination leads to an enhanced quality of life, and choice making is considered a central element in self-determination. Most learn choice making through a gradual release of responsibility by caregivers throughout their…

Modeling the Bullying Prevention Program Preferences of Educators: A Discrete Choice Conjoint Experiment

ERIC Educational Resources Information Center

Cunningham, Charles E.; Vaillancourt, Tracy; Rimas, Heather; Deal, Ken; Cunningham, Lesley; Short, Kathy; Chen, Yvonne

2009-01-01

We used discrete choice conjoint analysis to model the bullying prevention program preferences of educators. Using themes from computerized decision support lab focus groups (n = 45 educators), we composed 20 three-level bullying prevention program design attributes. Each of 1,176 educators completed 25 choice tasks presenting experimentally…

[Continuing medical education: how to write multiple choice questions].

PubMed

Soler Fernández, R; Méndez Díaz, C; Rodríguez García, E

2013-06-01

Evaluating professional competence in medicine is a difficult but indispensable task because it makes it possible to evaluate, at different times and from different perspectives, the extent to which the knowledge, skills, and values required for exercising the profession have been acquired. Tests based on multiple choice questions have been and continue to be among the most useful tools for objectively evaluating learning in medicine. When these tests are well designed and correctly used, they can stimulate learning and even measure higher cognitive skills. Designing a multiple choice test is a difficult task that requires knowledge of the material to be tested and of the methodology of test preparation as well as time to prepare the test. The aim of this article is to review what can be evaluated through multiple choice tests, the rules and guidelines that should be taken into account when writing multiple choice questions, the different formats that can be used, the most common errors in elaborating multiple choice tests, and how to analyze the results of the test to verify its quality. Copyright © 2012 SERAM. Published by Elsevier Espana. All rights reserved.

Amygdala lesions in rhesus monkeys fail to disrupt object choices based on internal context

PubMed Central

Rhodes, Sarah E. V.; Charles, David P.; Howland, Emily J.; Murray, Elisabeth A.

2012-01-01

We assessed the involvement of the amygdala in a task in which object choices were guided by internal context. Rhesus monkeys were trained on a biconditional discrimination whereby objects associated with food (but not water) were baited when the monkey was hungry, and objects associated with water (but not food) were baited when the monkey was thirsty. To solve this task monkeys were required to choose objects yielding the reward congruent with their internal motivational state. Lesions of the amygdala did not disrupt learning or performance of this task. We conclude that the involvement of the amygdala in selective-satiation tasks, which depends in part on a change in internal context, is not due to the amygdala playing a general role in representing, or using, internal context. PMID:22352788

Pitting intuitive and analytical thinking against each other: the case of transitivity.

PubMed

Rusou, Zohar; Zakay, Dan; Usher, Marius

2013-06-01

Identifying which thinking mode, intuitive or analytical, yields better decisions has been a major subject of inquiry by decision-making researchers. Yet studies show contradictory results. One possibility is that the ambiguity is due to the variability in experimental conditions across studies. Our hypothesis is that decision quality depends critically on the level of compatibility between the thinking mode employed in the decision and the nature of the decision-making task. In two experiments, we pitted intuition and analytical thinking against each other on tasks that were either mainly intuitive or mainly analytical. Thinking modes, as well as task characteristics, were manipulated in a factorial design, with choice transitivity as the dependent measure. Results showed higher choice consistency (transitivity) when thinking mode and the characteristics of the decision task were compatible.

Affective imposition influences risky choice: handedness points to the hemispheres.

PubMed

McElroy, Todd; Corbin, Jonathan

2010-07-01

The study of risk preference has become a widely investigated area of research. The current study is designed to investigate the relationship between handedness, hemispheric predominance and valence imposition in a risky-choice decision task. Research into the valence hypothesis (e.g., Ahern & Schwartz, 1985; Davidson, 1984) has shown that the left hemisphere is more active in processing positively valenced stimuli, whereas the right hemisphere is more active in processing negatively valenced stimuli. A total of 520 individuals (343 female, 117 male) participated in a self-imposed framing task and took a degree of handedness questionnaire. The results of the framing task and handedness questionnaire showed that participants' degree of handedness significantly influenced the positive/negative valence they imposed onto the framing task as well as their level of risk preference.

Choosing to regulate: does choice enhance craving regulation?

PubMed Central

Mobasser, Arian; Zeithamova, Dagmar; Pfeifer, Jennifer H

2018-01-01

Abstract Goal-directed behavior and lifelong well-being often depend on the ability to control appetitive motivations, such as cravings. Cognitive reappraisal is an effective way to modulate emotional states, including cravings, but is often studied under explicit instruction to regulate. Despite the strong prediction from Self-Determination Theory that choice should enhance task engagement and regulation success, little is known empirically about whether and how regulation is different when participants choose (vs are told) to exert control. To investigate how choice affects neural activity and regulation success, participants reappraised their responses to images of personally-craved foods while undergoing functional neuroimaging. Participants were either instructed to view or reappraise (‘no-choice’) or chose freely to view or reappraise (‘yes-choice’). Choice increased activity in the frontoparietal control network. We expected this activity would be associated with increased task engagement, resulting in better regulation success. However, contrary to this prediction, choice slightly reduced regulation success. Follow-up multivariate functional neuroimaging analyses indicated that choice likely disrupted allocation of limited cognitive resources during reappraisal. While unexpected, these results highlight the importance of studying upstream processes such as regulation choice, as they may affect the ability to regulate cravings and other emotional states. PMID:29462475

A Telescopic Binary Learning Machine for Training Neural Networks.

PubMed

Brunato, Mauro; Battiti, Roberto

2017-03-01

This paper proposes a new algorithm based on multiscale stochastic local search with binary representation for training neural networks [binary learning machine (BLM)]. We study the effects of neighborhood evaluation strategies, the effect of the number of bits per weight and that of the maximum weight range used for mapping binary strings to real values. Following this preliminary investigation, we propose a telescopic multiscale version of local search, where the number of bits is increased in an adaptive manner, leading to a faster search and to local minima of better quality. An analysis related to adapting the number of bits in a dynamic way is presented. The control on the number of bits, which happens in a natural manner in the proposed method, is effective to increase the generalization performance. The learning dynamics are discussed and validated on a highly nonlinear artificial problem and on real-world tasks in many application domains; BLM is finally applied to a problem requiring either feedforward or recurrent architectures for feedback control.

Diet-induced impulsivity: Effects of a high-fat and a high-sugar diet on impulsive choice in rats

PubMed Central

Pirkle, Jesseca R. A.; Kirkpatrick, Kimberly

2017-01-01

Impulsive choice is a common charactertistic among individuals with gambling problems, obesity, and substance abuse issues. Impulsive choice has been classified as a trans-disease process, and understanding the etiology of trait impulsivity could help to understand how diseases and disorders related to impulsive choice are manifested. The Western diet is a possible catalyst of impulsive choice as individuals who are obese and who eat diets high in fat and sugar are typically more impulsive. However, such correlational evidence is unable to discern the direction and causal nature of the relationship. The present study sought to determine how diet may directly contribute to impulsive choice. After 8 weeks of dietary exposure (high-fat, high-sugar, chow), the rats were tested on an impulsive choice task, which presented choices between a smaller-sooner reward (SS) and a larger-later reward (LL). Then, the rats were transferred to a chow diet and retested on the impulsive choice task. The high-sugar and high-fat groups made significantly more impulsive choices than the chow group. Both groups became more self-controlled when they were off the diet, but there were some residual effects of the diet on choice behavior. These results suggest that diet, specifically one high in processed fat or sugar, induces impulsive choice. This diet-induced impulsivity could be a precursor to other disorders that are characterized by impulsivity, such as diet-induced obesity, and could offer potential understanding of the trans-disease nature of impulsive choice. PMID:28662133

Diet-induced impulsivity: Effects of a high-fat and a high-sugar diet on impulsive choice in rats.

PubMed

Steele, Catherine C; Pirkle, Jesseca R A; Kirkpatrick, Kimberly

2017-01-01

Impulsive choice is a common charactertistic among individuals with gambling problems, obesity, and substance abuse issues. Impulsive choice has been classified as a trans-disease process, and understanding the etiology of trait impulsivity could help to understand how diseases and disorders related to impulsive choice are manifested. The Western diet is a possible catalyst of impulsive choice as individuals who are obese and who eat diets high in fat and sugar are typically more impulsive. However, such correlational evidence is unable to discern the direction and causal nature of the relationship. The present study sought to determine how diet may directly contribute to impulsive choice. After 8 weeks of dietary exposure (high-fat, high-sugar, chow), the rats were tested on an impulsive choice task, which presented choices between a smaller-sooner reward (SS) and a larger-later reward (LL). Then, the rats were transferred to a chow diet and retested on the impulsive choice task. The high-sugar and high-fat groups made significantly more impulsive choices than the chow group. Both groups became more self-controlled when they were off the diet, but there were some residual effects of the diet on choice behavior. These results suggest that diet, specifically one high in processed fat or sugar, induces impulsive choice. This diet-induced impulsivity could be a precursor to other disorders that are characterized by impulsivity, such as diet-induced obesity, and could offer potential understanding of the trans-disease nature of impulsive choice.

Experimental design and analysis of JND test on coded image/video

NASA Astrophysics Data System (ADS)

Lin, Joe Yuchieh; Jin, Lina; Hu, Sudeng; Katsavounidis, Ioannis; Li, Zhi; Aaron, Anne; Kuo, C.-C. Jay

2015-09-01

The visual Just-Noticeable-Difference (JND) metric is characterized by the detectable minimum amount of two visual stimuli. Conducting the subjective JND test is a labor-intensive task. In this work, we present a novel interactive method in performing the visual JND test on compressed image/video. JND has been used to enhance perceptual visual quality in the context of image/video compression. Given a set of coding parameters, a JND test is designed to determine the distinguishable quality level against a reference image/video, which is called the anchor. The JND metric can be used to save coding bitrates by exploiting the special characteristics of the human visual system. The proposed JND test is conducted using a binary-forced choice, which is often adopted to discriminate the difference in perception in a psychophysical experiment. The assessors are asked to compare coded image/video pairs and determine whether they are of the same quality or not. A bisection procedure is designed to find the JND locations so as to reduce the required number of comparisons over a wide range of bitrates. We will demonstrate the efficiency of the proposed JND test, report experimental results on the image and video JND tests.

Mechanisms of impulsive choice: II. Time-based interventions to improve self-control

PubMed Central

Smith, Aaron P.; Marshall, Andrew T.; Kirkpatrick, Kimberly

2014-01-01

Impulsive choice behavior has been proposed as a primary risk factor for other maladaptive behaviors (e.g., gambling, substance abuse). Recent research has suggested that timing processes may play a key role in impulsive choice behavior, and could provide an avenue for altering impulsive choice. Accordingly, the current experiments assessed a set of time-based behavioral interventions to increase self-control while simultaneously assessing effects on timing processes within the impulsive choice task. Three experiments assessed temporal interventions using a differential reinforcement of low rates task (Experiment 1) and exposure to either a variable or fixed interval schedule (Experiments 2–3). The efficacy of the interventions was assessed in Sprague-Dawley (Experiments 1–2) and Lewis (Experiment 3) rat strains. Impulsive choice behavior was assessed by measuring preferences of a smaller-sooner (SS) versus a larger-later (LL) reward, while timing of the SS and LL durations was measured during peak trials within the impulsive choice procedure. The rats showed an increased preference for the LL following all three time-based interventions and also displayed increased temporal precision. These results add to the increasing evidence that supports a possible role for temporal processing in impulsive choice behavior and supply novel behavioral interventions to decrease impulsive behavior. PMID:25444771

On the Flexibility of Basic Risk Attitudes in Monkeys.

PubMed

Farashahi, Shiva; Azab, Habiba; Hayden, Benjamin; Soltani, Alireza

2018-05-02

Monkeys and other animals appear to share with humans two risk attitudes predicted by prospect theory: an inverse-S-shaped probability-weighting (PW) function and a steeper utility curve for losses than for gains. These findings suggest that such preferences are stable traits with common neural substrates. We hypothesized instead that animals tailor their preferences to subtle changes in task contexts, making risk attitudes flexible. Previous studies used a limited number of outcomes, trial types, and contexts. To gain a broader perspective, we examined two large datasets of male macaques' risky choices: one from a task with real (juice) gains and another from a token task with gains and losses. In contrast to previous findings, monkeys were risk seeking for both gains and losses (i.e., lacked a reflection effect) and showed steeper gain than loss curves (loss seeking). Utility curves for gains were substantially different in the two tasks. Monkeys showed nearly linear PWs in one task and S-shaped ones in the other; neither task produced a consistent inverse-S-shaped curve. To account for these observations, we developed and tested various computational models of the processes involved in the construction of reward value. We found that adaptive differential weighting of prospective gamble outcomes could partially account for the observed differences in the utility functions across the two experiments and thus provide a plausible mechanism underlying flexible risk attitudes. Together, our results support the idea that risky choices are constructed flexibly at the time of elicitation and place important constraints on neural models of economic choice. SIGNIFICANCE STATEMENT We respond in reliable ways to risk, but are our risk preferences stable traits or ephemeral states? Using various computational models, we examined two large datasets of macaque risky choices in two different tasks. We observed several deviations from "classic" risk preferences seen in humans and monkeys: no reflection effect, loss seeking as opposed to loss aversion, and linear and S-shaped, as opposed to inverse-S-shaped, probability distortion. These results challenge the idea that our risk attitudes are evolved traits shared with the last common ancestor of macaques and humans, suggesting instead that behavioral flexibility is the hallmark of risky choice in primates. We show how this flexibility can emerge partly as a result of interactions between attentional and reward systems. Copyright © 2018 the authors 0270-6474/18/384383-16$15.00/0.

The Inner Processes Underlying Vocational Development.

ERIC Educational Resources Information Center

Bujold, Charles E.; And Others

Educational and occupational choices may be considered, from a developmental point of view, as long-term problems whose solutions imply a number of tasks. These tasks sequentially might be called exploration, crystallization, specification, and implementation. What are the processes involved in these tasks? What are the abilities which make…

Delay and probability discounting of multiple commodities in smokers and never-smokers using multiple-choice tasks.

PubMed

Poltavski, Dmitri V; Weatherly, Jeffrey N

2013-12-01

The purpose of the present study was to investigate temporal and probabilistic discounting in smokers and never-smokers, across a number of commodities, using a multiple-choice method. One hundred and eighty-two undergraduate university students, of whom 90 had never smoked, 73 were self-reported light smokers (<10 cigarettes/day), and 17 were heavy smokers (10+cigarettes/day), completed computerized batteries of delay and probability discounting questions pertaining to a total of eight commodities and administered in a multiple-choice format. In addition to cigarettes, monetary rewards, and health outcomes, the tasks included novel commodities such as ideal dating partner and retirement income. The results showed that heavy smokers probability discounted commodities at a significantly shallower rate than never-smokers, suggesting greater risk-taking. No effect of smoking status was observed for delay discounting questions. The only commodity that was probability discounted significantly less than others was 'finding an ideal dating partner'. The results suggest that probability discounting tasks using the multiple-choice format can discriminate between non-abstaining smokers and never-smokers and could be further explored in the context of behavioral and drug addictions.

Neural Correlates of Object-Associated Choice Behavior in the Perirhinal Cortex of Rats

PubMed Central

Ahn, Jae-Rong

2015-01-01

The perirhinal cortex (PRC) is reportedly important for object recognition memory, with supporting physiological evidence obtained largely from primate studies. Whether neurons in the rodent PRC also exhibit similar physiological correlates of object recognition, however, remains to be determined. We recorded single units from the PRC in a PRC-dependent, object-cued spatial choice task in which, when cued by an object image, the rat chose the associated spatial target from two identical discs appearing on a touchscreen monitor. The firing rates of PRC neurons were significantly modulated by critical events in the task, such as object sampling and choice response. Neuronal firing in the PRC was correlated primarily with the conjunctive relationships between an object and its associated choice response, although some neurons also responded to the choice response alone. However, we rarely observed a PRC neuron that represented a specific object exclusively regardless of spatial response in rats, although the neurons were influenced by the perceptual ambiguity of the object at the population level. Some PRC neurons fired maximally after a choice response, and this post-choice feedback signal significantly enhanced the neuronal specificity for the choice response in the subsequent trial. Our findings suggest that neurons in the rat PRC may not participate exclusively in object recognition memory but that their activity may be more dynamically modulated in conjunction with other variables, such as choice response and its outcomes. PMID:25632144

TCP performance in ATM networks: ABR parameter tuning and ABR/UBR comparisons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chien Fang; Lin, A.

1996-02-27

This paper explores two issues on TOP performance over ATM networks: ABR parameter tuning and performance comparison of binary mode ABR with enhanced UBR services. Of the fifteen parameters defined for ABR, two parameters dominate binary mode ABR performance: Rate Increase Factor (RIF) and Rate Decrease Factor (RDF). Using simulations, we study the effects of these two parameters on TOP over ABR performance. We compare TOP performance with different ABR parameter settings in terms of through-puts and fairness. The effects of different buffer sizes and LAN/WAN distances are also examined. We then compare TOP performance with the best ABR parametermore » setting with corresponding UBR service enhanced with Early Packet Discard and also with a fair buffer allocation scheme. The results show that TOP performance over binary mode ABR is very sensitive to parameter value settings, and that a poor choice of parameters can result in ABR performance worse than that of the much less expensive UBR-EPD scheme.« less

Restrictive Food Intake As A Choice – A Paradigm for Study

PubMed Central

Steinglass, Joanna; Foerde, Karin; Kostro, Katrina; Shohamy, Daphna; Timothy Walsh, B.

2014-01-01

Objective: Inadequate intake and preference for low-calorie foods are salient behavioral features of Anorexia Nervosa (AN). The neurocognitive mechanisms underlying pathological food choice have not been characterized. This study aimed to develop a new paradigm for experimentally modeling maladaptive food choice in AN. Method: Individuals with AN (n=22) and healthy controls (HC, n=20) participated in a computer-based Food Choice Task, adapted for individuals with eating disorders. Participants first rated 43 food images (including high-fat and low-fat items) for Healthiness and Tastiness; an item rated neutral on both blocks was then selected as the Reference item. On each of 42 subsequent trials participants were asked to choose between the food item presented and the Reference item. Results: The AN group was less likely to choose high-fat foods relative to HC, as evidenced both in multilevel logistic regression (z=2.59, p=0.009) and ANOVA (F(1,39)=7.80, p=0.008) analyses. Health ratings influenced choice significantly more in AN relative to HC (z=2.7, p=0.006), and were more related to Taste among AN (χ2=4.10, p=0.04). Additionally, Taste ratings declined with duration of illness(r=−0.50, p=0.02). Conclusions: The Food Choice Task captures the preference for low-fat foods among individuals with AN. The findings suggest that the experience of tastiness changes over time and may contribute to perpetuation of illness. By providing an experimental quantitative measure of food restriction, this task opens the door to new experimental investigations into the cognitive, affective and neural factors contributing to maladaptive food choices characteristic of AN. PMID:25130380

Restrictive food intake as a choice--a paradigm for study.

PubMed

Steinglass, Joanna; Foerde, Karin; Kostro, Katrina; Shohamy, Daphna; Walsh, B Timothy

2015-01-01

Inadequate intake and preference for low-calorie foods are salient behavioral features of Anorexia Nervosa (AN). The neurocognitive mechanisms underlying pathological food choice have not been characterized. This study aimed to develop a new paradigm for experimentally modeling maladaptive food choice in AN. Individuals with AN (n = 22) and healthy controls (HC, n = 20) participated in a computer-based Food Choice Task, adapted for individuals with eating disorders. Participants first rated 43 food images (including high-fat and low-fat items) for Healthiness and Tastiness; an item rated neutral on both blocks was then selected as the Reference item. On each of 42 subsequent trials participants were asked to choose between the food item presented and the Reference item. The AN group was less likely to choose high-fat foods relative to HC, as evidenced both in multilevel logistic regression (z = 2.59, p = .009) and ANOVA (F(1,39) = 7.80, p = .008) analyses. Health ratings influenced choice significantly more in AN relative to HC (z = 2.7, p = .006), and were more related to Taste among AN (χ(2) = 4.10, p = .04). Additionally, taste ratings declined with duration of illness (r = -.50, p = .02). The Food Choice Task captures the preference for low-fat foods among individuals with AN. The findings suggest that the experience of tastiness changes over time and may contribute to perpetuation of illness. By providing an experimental quantitative measure of food restriction, this task opens the door to new experimental investigations into the cognitive, affective, and neural factors contributing to maladaptive food choices characteristic of AN. © 2014 Wiley Periodicals, Inc.

Are dogs (Canis familiaris) misled more by their owners than by strangers in a food choice task?

PubMed

Marshall-Pescini, S; Prato-Previde, E; Valsecchi, P

2011-01-01

Dogs are highly skilled in understanding a large variety of human social cues and use them appropriately to solve a number of different cognitive tasks. They rely on human signals even when these are contradictory or misleading and ultimately prevent them from correctly solving a task. In the following two experiments, we investigated whether the owner and a stranger differently influenced dogs' choices in food discrimination tasks. In Experiment 1, 48 dogs were tested in 3 different conditions: (1) choice between a large and a small amount of dog pellets with no demonstration; (2) choice between a large and a small amount of dog pellets after having witnessed the owner/stranger favouring the small quantity; (3) choice between two single food pellets after observing the owner/stranger choosing one of them. In Experiment 2, 48 dogs could choose between two foods of different palatability: in Condition 1, dogs chose between a slice of sausage and a dry pellet with no demonstration. In Condition 2, the same choice was available but with a person (owner/stranger) showing a preference for the dry pellet. In Condition 3, dogs chose between a single dry pellet and 8 slices of sausage, with the person (owner/stranger) showing a preference for the pellet. In both experiments, dogs conformed to the human's indications even though these led to the selection of the less advantageous option (i.e. the smaller amount of food in Experiment 1 or the low quality food in Experiment 2). However, the owner and the stranger did not differently influence the dogs' behaviour. Results show that dogs are willing to follow a person's indication even when this is visibly (if perhaps only mildly) counterproductive to them and that they are socially prepared to rely equally on cues given by the owner and an unfamiliar friendly person.

Providing Information to Parents of Children with Mental Health Problems: A Discrete Choice Conjoint Analysis of Professional Preferences

ERIC Educational Resources Information Center

Cunningham, Charles E.; Deal, Ken; Rimas, Heather; Chen, Yvonne; Buchanan, Don H.; Sdao-Jarvie, Kathie

2009-01-01

We used discrete choice conjoint analysis to model the ways 645 children's mental health (CMH) professionals preferred to provide information to parents seeking CMH services. Participants completed 20 choice tasks presenting experimentally varied combinations of the study's 14 4-level CMH information transfer attributes. Latent class analysis…

The Effects of Choice on Intrinsic Motivation and Related Outcomes: A Meta-Analysis of Research Findings

ERIC Educational Resources Information Center

Patall, Erika A.; Cooper, Harris; Robinson, Jorgianne Civey

2008-01-01

A meta-analysis of 41 studies examined the effect of choice on intrinsic motivation and related outcomes in a variety of settings with both child and adult samples. Results indicated that providing choice enhanced intrinsic motivation, effort, task performance, and perceived competence, among other outcomes. Moderator tests revealed the effect…

The Effects of Spatial Stimulus-Response Compatibility on Choice Time Production Accuracy and Variability

ERIC Educational Resources Information Center

Rakitin, Brian C.

2005-01-01

Five experiments examined the relations between timing and attention using a choice time production task in which the latency of a spatial choice response is matched to a target interval (3 or 5 s). Experiments 1 and 2 indicated that spatial stimulus-response incompatibility increased nonscalar timing variability without affecting timing accuracy…

A Framework for Learner Agency in Online Spoken Interaction Tasks

ERIC Educational Resources Information Center

Knight, Janine; Barbera, Elena; Appel, Christine

2017-01-01

Learner agency, the capability of individual human beings to make choices and act on these choices in a way that makes a difference in their lives (Martin, 2004), is instrumental in second language learning because attainment is only arrived at by learner choice (Pavlenko & Lantolf, 2000). If attainment is understood as learner engagement in…

Caudate Microstimulation Increases Value of Specific Choices.

PubMed

Santacruz, Samantha R; Rich, Erin L; Wallis, Joni D; Carmena, Jose M

2017-11-06

Value-based decision-making involves an assessment of the value of items available and the actions required to obtain them. The basal ganglia are highly implicated in action selection and goal-directed behavior [1-4], and the striatum in particular plays a critical role in arbitrating between competing choices [5-9]. Previous work has demonstrated that neural activity in the caudate nucleus is modulated by task-relevant action values [6, 8]. Nonetheless, how value is represented and maintained in the striatum remains unclear since decision-making in these tasks relied on spatially lateralized responses, confounding the ability to generalize to a more abstract choice task [6, 8, 9]. Here, we investigate striatal value representations by applying caudate electrical stimulation in macaque monkeys (n = 3) to bias decision-making in a task that divorces the value of a stimulus from motor action. Electrical microstimulation is known to induce neural plasticity [10, 11], and caudate microstimulation in primates has been shown to accelerate associative learning [12, 13]. Our results indicate that stimulation paired with a particular stimulus increases selection of that stimulus, and this effect was stimulus dependent and action independent. The modulation of choice behavior using microstimulation was best modeled as resulting from changes in stimulus value. Caudate neural recordings (n = 1) show that changes in value-coding neuron activity are stimulus value dependent. We argue that caudate microstimulation can differentially increase stimulus values independent of action, and unilateral manipulations of value are sufficient to mediate choice behavior. These results support potential future applications of microstimulation to correct maladaptive plasticity underlying dysfunctional decision-making related to neuropsychiatric conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Context effects and the temporal stability of stated preferences.

PubMed

Liebe, Ulf; Hundeshagen, Cordula; Beyer, Heiko; Cramon-Taubadel, Stephan von

2016-11-01

In stated preference studies it is assumed that individuals' answers reflect true preferences and are stable over time. We test these two assumptions of validity and reliability using as an example a choice experiment study on ethical consumption that measures preferences for a Peace Product jointly produced by Israeli and Palestinian producers as well as for organic products. In a web survey conducted in Germany, we investigate the validity assumption by manipulating the question context and presenting one group of respondents with questions on anti-Semitic and anti-Arabic attitudes before the choice tasks, and presenting another group with these questions after the choice tasks. In order to test the assumption of temporal stability, the same experimental set-up was repeated in a second survey based on a new sample ten months after the first. However, prior to the second survey an external event, a major violent dispute between Israelis and the Palestinians occurred. Overall, we find evidence for a context effect but not for temporal instability. In both surveys, the placement of the attitudinal questions before the choice tasks has a positive effect on the valuation of products from Israel, Palestinian products and the Peace Product (i.e. a directional context effect). The respondents seem to act according to an anti-discrimination norm. In line with this reasoning, we find an attention shift caused by the attitudinal questions. Organic products are valued much less positively if discriminatory attitudes are surveyed before the choice tasks. Furthermore, despite the violent dispute, stated preferences are very stable over time. This indicates high reliability of stated preference studies and encourages the use of study results by private and public decision makers. Copyright © 2016 Elsevier Inc. All rights reserved.

Behavioral variability of choices versus structural inconsistency of preferences.

PubMed

Regenwetter, Michel; Davis-Stober, Clintin P

2012-04-01

Theories of rational choice often make the structural consistency assumption that every decision maker's binary strict preference among choice alternatives forms a strict weak order. Likewise, the very concept of a utility function over lotteries in normative, prescriptive, and descriptive theory is mathematically equivalent to strict weak order preferences over those lotteries, while intransitive heuristic models violate such weak orders. Using new quantitative interdisciplinary methodologies, we dissociate the variability of choices from the structural inconsistency of preferences. We show that laboratory choice behavior among stimuli of a classical "intransitivity" paradigm is, in fact, consistent with variable strict weak order preferences. We find that decision makers act in accordance with a restrictive mathematical model that, for the behavioral sciences, is extraordinarily parsimonious. Our findings suggest that the best place to invest future behavioral decision research is not in the development of new intransitive decision models but rather in the specification of parsimonious models consistent with strict weak order(s), as well as heuristics and other process models that explain why preferences appear to be weakly ordered.

Amygdala and Ventral Striatum Make Distinct Contributions to Reinforcement Learning.

PubMed

Costa, Vincent D; Dal Monte, Olga; Lucas, Daniel R; Murray, Elisabeth A; Averbeck, Bruno B

2016-10-19

Reinforcement learning (RL) theories posit that dopaminergic signals are integrated within the striatum to associate choices with outcomes. Often overlooked is that the amygdala also receives dopaminergic input and is involved in Pavlovian processes that influence choice behavior. To determine the relative contributions of the ventral striatum (VS) and amygdala to appetitive RL, we tested rhesus macaques with VS or amygdala lesions on deterministic and stochastic versions of a two-arm bandit reversal learning task. When learning was characterized with an RL model relative to controls, amygdala lesions caused general decreases in learning from positive feedback and choice consistency. By comparison, VS lesions only affected learning in the stochastic task. Moreover, the VS lesions hastened the monkeys' choice reaction times, which emphasized a speed-accuracy trade-off that accounted for errors in deterministic learning. These results update standard accounts of RL by emphasizing distinct contributions of the amygdala and VS to RL. Published by Elsevier Inc.

Amygdala and ventral striatum make distinct contributions to reinforcement learning

PubMed Central

Costa, Vincent D.; Monte, Olga Dal; Lucas, Daniel R.; Murray, Elisabeth A.; Averbeck, Bruno B.

2016-01-01

Summary Reinforcement learning (RL) theories posit that dopaminergic signals are integrated within the striatum to associate choices with outcomes. Often overlooked is that the amygdala also receives dopaminergic input and is involved in Pavlovian processes that influence choice behavior. To determine the relative contributions of the ventral striatum (VS) and amygdala to appetitive RL we tested rhesus macaques with VS or amygdala lesions on deterministic and stochastic versions of a two-arm bandit reversal learning task. When learning was characterized with a RL model relative to controls, amygdala lesions caused general decreases in learning from positive feedback and choice consistency. By comparison, VS lesions only affected learning in the stochastic task. Moreover, the VS lesions hastened the monkeys’ choice reaction times, which emphasized a speed-accuracy tradeoff that accounted for errors in deterministic learning. These results update standard accounts of RL by emphasizing distinct contributions of the amygdala and VS to RL. PMID:27720488

A comparison of adaptive sampling designs and binary spatial models: A simulation study using a census of Bromus inermis

USGS Publications Warehouse

Irvine, Kathryn M.; Thornton, Jamie; Backus, Vickie M.; Hohmann, Matthew G.; Lehnhoff, Erik A.; Maxwell, Bruce D.; Michels, Kurt; Rew, Lisa

2013-01-01

Commonly in environmental and ecological studies, species distribution data are recorded as presence or absence throughout a spatial domain of interest. Field based studies typically collect observations by sampling a subset of the spatial domain. We consider the effects of six different adaptive and two non-adaptive sampling designs and choice of three binary models on both predictions to unsampled locations and parameter estimation of the regression coefficients (species–environment relationships). Our simulation study is unique compared to others to date in that we virtually sample a true known spatial distribution of a nonindigenous plant species, Bromus inermis. The census of B. inermis provides a good example of a species distribution that is both sparsely (1.9 % prevalence) and patchily distributed. We find that modeling the spatial correlation using a random effect with an intrinsic Gaussian conditionally autoregressive prior distribution was equivalent or superior to Bayesian autologistic regression in terms of predicting to un-sampled areas when strip adaptive cluster sampling was used to survey B. inermis. However, inferences about the relationships between B. inermis presence and environmental predictors differed between the two spatial binary models. The strip adaptive cluster designs we investigate provided a significant advantage in terms of Markov chain Monte Carlo chain convergence when trying to model a sparsely distributed species across a large area. In general, there was little difference in the choice of neighborhood, although the adaptive king was preferred when transects were randomly placed throughout the spatial domain.

Decomposing task-switching costs with the diffusion model.

PubMed

Schmitz, Florian; Voss, Andreas

2012-02-01

In four experiments, task-switching processes were investigated with variants of the alternating runs paradigm and the explicit cueing paradigm. The classical diffusion model for binary decisions (Ratcliff, 1978) was used to dissociate different components of task-switching costs. Findings can be reconciled with the view that task-switching processes take place in successive phases as postulated by multiple-components models of task switching (e.g., Mayr & Kliegl, 2003; Ruthruff, Remington, & Johnston, 2001). At an earlier phase, task-set reconfiguration (Rogers & Monsell, 1995) or cue-encoding (Schneider & Logan, 2005) takes place, at a later phase, the response is selected in accord with constraints set in the first phase. Inertia effects (Allport, Styles, & Hsieh, 1994; Allport & Wylie, 2000) were shown to affect this later stage. Additionally, findings support the notion that response caution contributes to both global as well as to local switching costs when task switches are predictable.

Rapid Acquisition of Choice and Timing and the Provenance of the Terminal-Link Effect

ERIC Educational Resources Information Center

Kyonka, Elizabeth G. E.; Grace, Randolph C.

2010-01-01

Eight pigeons responded in a concurrent-chains procedure in which terminal-link schedules changed pseudorandomly across sessions. Pairs of terminal-link delays either summed to 15 s or to 45 s. Across sessions, the location of the shorter terminal link changed according to a pseudorandom binary sequence. On some terminal links, food was withheld…

Model many-body Stoner Hamiltonian for binary FeCr alloys

NASA Astrophysics Data System (ADS)

Nguyen-Manh, D.; Dudarev, S. L.

2009-09-01

We derive a model tight-binding many-body d -electron Stoner Hamiltonian for FeCr binary alloys and investigate the sensitivity of its mean-field solutions to the choice of hopping integrals and the Stoner exchange parameters. By applying the local charge-neutrality condition within a self-consistent treatment we show that the negative enthalpy-of-mixing anomaly characterizing the alloy in the low chromium concentration limit is due entirely to the presence of the on-site exchange Stoner terms and that the occurrence of this anomaly is not specifically related to the choice of hopping integrals describing conventional chemical bonding between atoms in the alloy. The Bain transformation pathway computed, using the proposed model Hamiltonian, for the Fe15Cr alloy configuration is in excellent agreement with ab initio total-energy calculations. Our investigation also shows how the parameters of a tight-binding many-body model Hamiltonian for a magnetic alloy can be derived from the comparison of its mean-field solutions with other, more accurate, mean-field approximations (e.g., density-functional calculations), hence stimulating the development of large-scale computational algorithms for modeling radiation damage effects in magnetic alloys and steels.

The Nature of Phoneme Representation in Spoken Word Recognition

ERIC Educational Resources Information Center

Gaskell, M. Gareth; Quinlan, Philip T.; Tamminen, Jakke; Cleland, Alexandra A.

2008-01-01

Four experiments used the psychological refractory period logic to examine whether integration of multiple sources of phonemic information has a decisional locus. All experiments made use of a dual-task paradigm in which participants made forced-choice color categorization (Task 1) and phoneme categorization (Task 2) decisions at varying stimulus…

The Role of Response Bias in Perceptual Learning

PubMed Central

2015-01-01

Sensory judgments improve with practice. Such perceptual learning is often thought to reflect an increase in perceptual sensitivity. However, it may also represent a decrease in response bias, with unpracticed observers acting in part on a priori hunches rather than sensory evidence. To examine whether this is the case, 55 observers practiced making a basic auditory judgment (yes/no amplitude-modulation detection or forced-choice frequency/amplitude discrimination) over multiple days. With all tasks, bias was present initially, but decreased with practice. Notably, this was the case even on supposedly “bias-free,” 2-alternative forced-choice, tasks. In those tasks, observers did not favor the same response throughout (stationary bias), but did favor whichever response had been correct on previous trials (nonstationary bias). Means of correcting for bias are described. When applied, these showed that at least 13% of perceptual learning on a forced-choice task was due to reduction in bias. In other situations, changes in bias were shown to obscure the true extent of learning, with changes in estimated sensitivity increasing once bias was corrected for. The possible causes of bias and the implications for our understanding of perceptual learning are discussed. PMID:25867609

Final Sampling Bias in Haptic Judgments: How Final Touch Affects Decision-Making.

PubMed

Mitsuda, Takashi; Yoshioka, Yuichi

2018-01-01

When people make a choice between multiple items, they usually evaluate each item one after the other repeatedly. The effect of the order and number of evaluating items on one's choices is essential to understanding the decision-making process. Previous studies have shown that when people choose a favorable item from two items, they tend to choose the item that they evaluated last. This tendency has been observed regardless of sensory modalities. This study investigated the origin of this bias by using three experiments involving two-alternative forced-choice tasks using handkerchiefs. First, the bias appeared in a smoothness discrimination task, which indicates that the bias was not based on judgments of preference. Second, the handkerchief that was touched more often tended to be chosen more frequently in the preference task, but not in the smoothness discrimination task, indicating that a mere exposure effect enhanced the bias. Third, in the condition where the number of touches did not differ between handkerchiefs, the bias appeared when people touched a handkerchief they wanted to touch last, but not when people touched the handkerchief that was predetermined. This finding suggests a direct coupling between final voluntary touching and judgment.

Mental Imagery and Idiom Understanding in Adults: Examining Dual Coding Theory

ERIC Educational Resources Information Center

Hung, Pei-Fang

2010-01-01

This study examined idiom understanding in 120 neurologically healthy adults, ages 20-29 (20s Group), 40-49 (40s Group), 60-69 (60s Group), and 80-89 (80s Group) years old. Each participant was administered a familiarity task, definition explanation task, mental imagery task, and forced-choice comprehension task. Twenty idioms, 10 transparent and…

Brain structure, executive function and appetitive traits in adolescent obesity.

PubMed

de Groot, C J; van den Akker, E L T; Rings, E H H M; Delemarre-van de Waal, H A; van der Grond, J

2017-08-01

Children with obesity show differences in brain structure, executive function and appetitive traits when compared with lean peers. Little is known on the relationship between brain structure and these traits. To investigate the relationship between differences in brain structure and executive function and appetitive traits, in obese and lean adolescents. MRI was used to measure cortical thickness and subcortical volumes. Executive function was measured by a Stop Signal-and a Choice Delay Task. Appetitive traits were measured using the Child Eating Behaviour Questionnaire. Adolescents with obesity had greater volumes of the pallidum; 1.78 mL (SE 0.03, p=0.014), when compared with controls; 1.65 mL (SE 0.02). In the group with obesity, greater pallidum volume was positively associated with the ability to delay reward in the Choice Delay Task (p=0.012). The association between pallidum volumes and Choice Delay Task in obese adolescents supports the hypothesis that the pallidum plays an important role in executive dysfunction in obese children. © 2016 World Obesity Federation.

Feedback-related brain activity predicts learning from feedback in multiple-choice testing.

PubMed

Ernst, Benjamin; Steinhauser, Marco

2012-06-01

Different event-related potentials (ERPs) have been shown to correlate with learning from feedback in decision-making tasks and with learning in explicit memory tasks. In the present study, we investigated which ERPs predict learning from corrective feedback in a multiple-choice test, which combines elements from both paradigms. Participants worked through sets of multiple-choice items of a Swahili-German vocabulary task. Whereas the initial presentation of an item required the participants to guess the answer, corrective feedback could be used to learn the correct response. Initial analyses revealed that corrective feedback elicited components related to reinforcement learning (FRN), as well as to explicit memory processing (P300) and attention (early frontal positivity). However, only the P300 and early frontal positivity were positively correlated with successful learning from corrective feedback, whereas the FRN was even larger when learning failed. These results suggest that learning from corrective feedback crucially relies on explicit memory processing and attentional orienting to corrective feedback, rather than on reinforcement learning.

Amygdala lesions in rhesus monkeys fail to disrupt object choices based on internal context.

PubMed

Rhodes, Sarah E V; Charles, David P; Howland, Emily J; Murray, Elisabeth A

2012-04-01

We assessed the involvement of the amygdala in a task in which object choices were guided by internal context. Rhesus monkeys were trained on a biconditional discrimination whereby objects associated with food (but not water) were baited when the monkey was hungry, and objects associated with water (but not food) were baited when the monkey was thirsty. To solve this task, monkeys were required to choose objects yielding the reward congruent with their internal motivational state. Lesions of the amygdala did not disrupt learning or performance of this task. We conclude that the involvement of the amygdala in selective-satiation tasks, which depends in part on a change in internal context, is not due to the amygdala playing a general role in representing, or using, internal context. (c) 2012 APA, all rights reserved

Prenatal cocaine exposure impairs selective attention: evidence from serial reversal and extradimensional shift tasks.

PubMed

Garavan, H; Morgan, R E; Mactutus, C F; Levitsky, D A; Booze, R M; Strupp, B J

2000-08-01

This study assessed the effects of prenatal cocaine exposure on cognitive functioning, using an intravenous (IV) rodent model that closely mimics the pharmacokinetics seen in humans after smoking or IV injection and that avoids maternal stress and undernutrition. Cocaine-exposed males were significantly impaired on a 3-choice, but not 2-choice, olfactory serial reversal learning task. Both male and female cocaine-exposed rats were significantly impaired on extradimensional shift tasks that required shifting from olfactory to spatial cues; however, they showed no impairment when required to shift from spatial to olfactory cues. In-depth analyses of discrete learning phases implicated deficient selective attention as the basis of impairment in both tasks. These data provide clear evidence that prenatal cocaine exposure produces long-lasting cognitive dysfunction, but they also underscore the specificity of the impairment.

Nonenculturated orangutans' (Pongo pygmaeus) use of experimenter-given manual and facial cues in an object-choice task.

PubMed

Byrnit, Jill T

2004-09-01

Several experiments have been performed, to examine whether nonhuman primates are able to make use of experimenter-given manual and facial (visual) cues to direct their attention to a baited object. Contrary to the performance of prosimians and monkeys, great apes repeatedly have shown task efficiency in experiments such as these. However, many great ape subjects used have been "enculturated" individuals. In the present study, 3 nonenculturated orangutans (Pongo pygmaeus) were tested for their ability to use experimenter-given pointing, gazing, and glancing cues in an object-choice task. All subjects readily made use of the pointing gesture. However, when subjects were left with only gazing or glancing cues, their performance deteriorated markedly, and they were not able to complete the task. ((c) 2004 APA, all rights reserved).

Method of optimization onboard communication network

NASA Astrophysics Data System (ADS)

Platoshin, G. A.; Selvesuk, N. I.; Semenov, M. E.; Novikov, V. M.

2018-02-01

In this article the optimization levels of onboard communication network (OCN) are proposed. We defined the basic parameters, which are necessary for the evaluation and comparison of modern OCN, we identified also a set of initial data for possible modeling of the OCN. We also proposed a mathematical technique for implementing the OCN optimization procedure. This technique is based on the principles and ideas of binary programming. It is shown that the binary programming technique allows to obtain an inherently optimal solution for the avionics tasks. An example of the proposed approach implementation to the problem of devices assignment in OCN is considered.

Prefrontal spatial working memory network predicts animal's decision making in a free choice saccade task.

PubMed

Mochizuki, Kei; Funahashi, Shintaro

2016-01-01

While neurons in the lateral prefrontal cortex (PFC) encode spatial information during the performance of working memory tasks, they are also known to participate in subjective behavior such as spatial attention and action selection. In the present study, we analyzed the activity of primate PFC neurons during the performance of a free choice memory-guided saccade task in which the monkeys needed to choose a saccade direction by themselves. In trials when the receptive field location was subsequently chosen by the animal, PFC neurons with spatially selective visual response started to show greater activation before cue onset. This result suggests that the fluctuation of firing before cue presentation prematurely biased the representation of a certain spatial location and eventually encouraged the subsequent choice of that location. In addition, modulation of the activity by the animal's choice was observed only in neurons with high sustainability of activation and was also dependent on the spatial configuration of the visual cues. These findings were consistent with known characteristics of PFC neurons in information maintenance in spatial working memory function. These results suggest that precue fluctuation of spatial representation was shared and enhanced through the working memory network in the PFC and could finally influence the animal's free choice of saccade direction. The present study revealed that the PFC plays an important role in decision making in a free choice condition and that the dynamics of decision making are constrained by the network architecture embedded in this cortical area. Copyright © 2016 the American Physiological Society.

Combining multiple decisions: applications to bioinformatics

NASA Astrophysics Data System (ADS)

Yukinawa, N.; Takenouchi, T.; Oba, S.; Ishii, S.

2008-01-01

Multi-class classification is one of the fundamental tasks in bioinformatics and typically arises in cancer diagnosis studies by gene expression profiling. This article reviews two recent approaches to multi-class classification by combining multiple binary classifiers, which are formulated based on a unified framework of error-correcting output coding (ECOC). The first approach is to construct a multi-class classifier in which each binary classifier to be aggregated has a weight value to be optimally tuned based on the observed data. In the second approach, misclassification of each binary classifier is formulated as a bit inversion error with a probabilistic model by making an analogy to the context of information transmission theory. Experimental studies using various real-world datasets including cancer classification problems reveal that both of the new methods are superior or comparable to other multi-class classification methods.

The Testing Methods and Gender Differences in Multiple-Choice Assessment

NASA Astrophysics Data System (ADS)

Ng, Annie W. Y.; Chan, Alan H. S.

2009-10-01

This paper provides a comprehensive review of the multiple-choice assessment in the past two decades for facilitating people to conduct effective testing in various subject areas. It was revealed that a variety of multiple-choice test methods viz. conventional multiple-choice, liberal multiple-choice, elimination testing, confidence marking, probability testing, and order-of-preference scheme are available for use in assessing subjects' knowledge and decision ability. However, the best multiple-choice test method for use has not yet been identified. The review also indicated that the existence of gender differences in multiple-choice task performance might be due to the test area, instruction/scoring condition, and item difficulty.

Analysis of methods of processing of expert information by optimization of administrative decisions

NASA Astrophysics Data System (ADS)

Churakov, D. Y.; Tsarkova, E. G.; Marchenko, N. D.; Grechishnikov, E. V.

2018-03-01

In the real operation the measure definition methodology in case of expert estimation of quality and reliability of application-oriented software products is offered. In operation methods of aggregation of expert estimates on the example of a collective choice of an instrumental control projects in case of software development of a special purpose for needs of institutions are described. Results of operation of dialogue decision making support system are given an algorithm of the decision of the task of a choice on the basis of a method of the analysis of hierarchies and also. The developed algorithm can be applied by development of expert systems to the solution of a wide class of the tasks anyway connected to a multicriteria choice.

No Effect of Commercial Cognitive Training on Brain Activity, Choice Behavior, or Cognitive Performance.

PubMed

Kable, Joseph W; Caulfield, M Kathleen; Falcone, Mary; McConnell, Mairead; Bernardo, Leah; Parthasarathi, Trishala; Cooper, Nicole; Ashare, Rebecca; Audrain-McGovern, Janet; Hornik, Robert; Diefenbach, Paul; Lee, Frank J; Lerman, Caryn

2017-08-02

Increased preference for immediate over delayed rewards and for risky over certain rewards has been associated with unhealthy behavioral choices. Motivated by evidence that enhanced cognitive control can shift choice behavior away from immediate and risky rewards, we tested whether training executive cognitive function could influence choice behavior and brain responses. In this randomized controlled trial, 128 young adults (71 male, 57 female) participated in 10 weeks of training with either a commercial web-based cognitive training program or web-based video games that do not specifically target executive function or adapt the level of difficulty throughout training. Pretraining and post-training, participants completed cognitive assessments and functional magnetic resonance imaging during performance of the following validated decision-making tasks: delay discounting (choices between smaller rewards now vs larger rewards in the future) and risk sensitivity (choices between larger riskier rewards vs smaller certain rewards). Contrary to our hypothesis, we found no evidence that cognitive training influences neural activity during decision-making; nor did we find effects of cognitive training on measures of delay discounting or risk sensitivity. Participants in the commercial training condition improved with practice on the specific tasks they performed during training, but participants in both conditions showed similar improvement on standardized cognitive measures over time. Moreover, the degree of improvement was comparable to that observed in individuals who were reassessed without any training whatsoever. Commercial adaptive cognitive training appears to have no benefits in healthy young adults above those of standard video games for measures of brain activity, choice behavior, or cognitive performance. SIGNIFICANCE STATEMENT Engagement of neural regions and circuits important in executive cognitive function can bias behavioral choices away from immediate rewards. Activity in these regions may be enhanced through adaptive cognitive training. Commercial brain training programs claim to improve a broad range of mental processes; however, evidence for transfer beyond trained tasks is mixed. We undertook the first randomized controlled trial of the effects of commercial adaptive cognitive training (Lumosity) on neural activity and decision-making in young adults ( N = 128) compared with an active control (playing on-line video games). We found no evidence for relative benefits of cognitive training with respect to changes in decision-making behavior or brain response, or for cognitive task performance beyond those specifically trained. Copyright © 2017 the authors 0270-6474/17/377390-13$15.00/0.

No Effect of Commercial Cognitive Training on Brain Activity, Choice Behavior, or Cognitive Performance

PubMed Central

Caulfield, M. Kathleen; McConnell, Mairead; Bernardo, Leah; Parthasarathi, Trishala; Cooper, Nicole; Ashare, Rebecca; Audrain-McGovern, Janet; Lee, Frank J.; Lerman, Caryn

2017-01-01

Increased preference for immediate over delayed rewards and for risky over certain rewards has been associated with unhealthy behavioral choices. Motivated by evidence that enhanced cognitive control can shift choice behavior away from immediate and risky rewards, we tested whether training executive cognitive function could influence choice behavior and brain responses. In this randomized controlled trial, 128 young adults (71 male, 57 female) participated in 10 weeks of training with either a commercial web-based cognitive training program or web-based video games that do not specifically target executive function or adapt the level of difficulty throughout training. Pretraining and post-training, participants completed cognitive assessments and functional magnetic resonance imaging during performance of the following validated decision-making tasks: delay discounting (choices between smaller rewards now vs larger rewards in the future) and risk sensitivity (choices between larger riskier rewards vs smaller certain rewards). Contrary to our hypothesis, we found no evidence that cognitive training influences neural activity during decision-making; nor did we find effects of cognitive training on measures of delay discounting or risk sensitivity. Participants in the commercial training condition improved with practice on the specific tasks they performed during training, but participants in both conditions showed similar improvement on standardized cognitive measures over time. Moreover, the degree of improvement was comparable to that observed in individuals who were reassessed without any training whatsoever. Commercial adaptive cognitive training appears to have no benefits in healthy young adults above those of standard video games for measures of brain activity, choice behavior, or cognitive performance. SIGNIFICANCE STATEMENT Engagement of neural regions and circuits important in executive cognitive function can bias behavioral choices away from immediate rewards. Activity in these regions may be enhanced through adaptive cognitive training. Commercial brain training programs claim to improve a broad range of mental processes; however, evidence for transfer beyond trained tasks is mixed. We undertook the first randomized controlled trial of the effects of commercial adaptive cognitive training (Lumosity) on neural activity and decision-making in young adults (N = 128) compared with an active control (playing on-line video games). We found no evidence for relative benefits of cognitive training with respect to changes in decision-making behavior or brain response, or for cognitive task performance beyond those specifically trained. PMID:28694338

Optogenetic Inhibition Reveals Distinct Roles for Basolateral Amygdala Activity at Discrete Time Points during Risky Decision Making.

PubMed

Orsini, Caitlin A; Hernandez, Caesar M; Singhal, Sarthak; Kelly, Kyle B; Frazier, Charles J; Bizon, Jennifer L; Setlow, Barry

2017-11-29

Decision making is a multifaceted process, consisting of several distinct phases that likely require different cognitive operations. Previous work showed that the basolateral amygdala (BLA) is a critical substrate for decision making involving risk of punishment; however, it is unclear how the BLA is recruited at different stages of the decision process. To this end, the current study used optogenetics to inhibit the BLA during specific task phases in a model of risky decision making (risky decision-making task) in which rats choose between a small, "safe" reward and a large reward accompanied by varying probabilities of footshock punishment. Male Long-Evans rats received intra-BLA microinjections of viral vectors carrying either halorhodopsin (eNpHR3.0-mCherry) or mCherry alone (control) followed by optic fiber implants and were trained in the risky decision-making task. Laser delivery during the task occurred during intertrial interval, deliberation, or reward outcome phases, the latter of which was further divided into the three possible outcomes (small, safe; large, unpunished; large, punished). Inhibition of the BLA selectively during the deliberation phase decreased choice of the large, risky outcome (decreased risky choice). In contrast, BLA inhibition selectively during delivery of the large, punished outcome increased risky choice. Inhibition had no effect during the other phases, nor did laser delivery affect performance in control rats. Collectively, these data indicate that the BLA can either inhibit or promote choice of risky options, depending on the phase of the decision process in which it is active. SIGNIFICANCE STATEMENT To date, most behavioral neuroscience research on neural mechanisms of decision making has used techniques that preclude assessment of distinct phases of the decision process. Here we show that optogenetic inhibition of the BLA has opposite effects on choice behavior in a rat model of risky decision making, depending on the phase in which inhibition occurs. BLA inhibition during a period of deliberation between small, safe and large, risky outcomes decreased risky choice. In contrast, BLA inhibition during receipt of the large, punished outcome increased risky choice. These findings highlight the importance of temporally targeted approaches to understand neural substrates underlying complex cognitive processes. More importantly, they reveal novel information about dynamic BLA modulation of risky choice. Copyright © 2017 the authors 0270-6474/17/3711537-12$15.00/0.

Intertemporal choice in lemurs.

PubMed

Stevens, Jeffrey R; Mühlhoff, Nelly

2012-02-01

Different species vary in their ability to wait for delayed rewards in intertemporal choice tasks. Models of rate maximization account for part of this variation, but other factors such as social structure and feeding ecology seem to underly some species differences. Though studies have evaluated intertemporal choice in several primate species, including Old World monkeys, New World monkeys, and apes, prosimians have not been tested. This study investigated intertemporal choices in three species of lemur (black-and-white ruffed lemurs, Varecia variegata, red ruffed lemurs, Varecia rubra, and black lemurs, Eulemur macaco) to assess how they compare to other primate species and whether their choices are consistent with rate maximization. We offered lemurs a choice between two food items available immediately and six food items available after a delay. We found that by adjusting the delay to the larger reward, the lemurs were indifferent between the two options at a mean delay of 17 s, ranging from 9 to 25 s. These data are comparable to data collected from common marmosets (Callithrix jacchus). The lemur data were not consistent with models of rate maximization. The addition of lemurs to the list of species tested in these tasks will help uncover the role of life history and socio-ecological factors influencing intertemporal choices. Copyright © 2011 Elsevier B.V. All rights reserved.

An Evaluation of the Value of Choice-Making Opportunities in Single-Operant Arrangements: Simple Fixed- and Progressive-Ratio Schedules

ERIC Educational Resources Information Center

Tiger, Jeffrey H.; Toussaint, Karen A.; Roath, Christopher T.

2010-01-01

The current study compared the effects of choice and no-choice reinforcement conditions on the task responding of 3 children with autism across 2 single-operant paradigm reinforcer assessments. The first assessment employed simple fixed-ratio (FR) schedules; the second used progressive-ratio (PR) schedules. The latter assessment identified the…

Is Making a Risky Choice Based on a Weighting and Adding Process? An Eye-Tracking Investigation

ERIC Educational Resources Information Center

Su, Yin; Rao, Li-Lin; Sun, Hong-Yue; Du, Xue-Lei; Li, Xingshan; Li, Shu

2013-01-01

The debate about whether making a risky choice is based on a weighting and adding process has a long history and is still unresolved. To address this long-standing controversy, we developed a comparative paradigm. Participants' eye movements in 2 risky choice tasks that required participants to choose between risky options in single-play and…

Quantitative prediction of perceptual decisions during near-threshold fear detection

NASA Astrophysics Data System (ADS)

Pessoa, Luiz; Padmala, Srikanth

2005-04-01

A fundamental goal of cognitive neuroscience is to explain how mental decisions originate from basic neural mechanisms. The goal of the present study was to investigate the neural correlates of perceptual decisions in the context of emotional perception. To probe this question, we investigated how fluctuations in functional MRI (fMRI) signals were correlated with behavioral choice during a near-threshold fear detection task. fMRI signals predicted behavioral choice independently of stimulus properties and task accuracy in a network of brain regions linked to emotional processing: posterior cingulate cortex, medial prefrontal cortex, right inferior frontal gyrus, and left insula. We quantified the link between fMRI signals and behavioral choice in a whole-brain analysis by determining choice probabilities by means of signal-detection theory methods. Our results demonstrate that voxel-wise fMRI signals can reliably predict behavioral choice in a quantitative fashion (choice probabilities ranged from 0.63 to 0.78) at levels comparable to neuronal data. We suggest that the conscious decision that a fearful face has been seen is represented across a network of interconnected brain regions that prepare the organism to appropriately handle emotionally challenging stimuli and that regulate the associated emotional response. decision making | emotion | functional MRI

Task choice and semantic interference in picture naming.

PubMed

Piai, Vitória; Roelofs, Ardi; Schriefers, Herbert

2015-05-01

Evidence from dual-task performance indicates that speakers prefer not to select simultaneous responses in picture naming and another unrelated task, suggesting a response selection bottleneck in naming. In particular, when participants respond to tones with a manual response and name pictures with superimposed semantically related or unrelated distractor words, semantic interference in naming tends to be constant across stimulus onset asynchronies (SOAs) between the tone stimulus and the picture-word stimulus. In the present study, we examine whether semantic interference in picture naming depends on SOA in case of a task choice (naming the picture vs reading the word of a picture-word stimulus) based on tones. This situation requires concurrent processing of the tone stimulus and the picture-word stimulus, but not a manual response to the tones. On each trial, participants either named a picture or read aloud a word depending on the pitch of a tone, which was presented simultaneously with picture-word onset or 350 ms or 1000 ms before picture-word onset. Semantic interference was present with tone pre-exposure, but absent when tone and picture-word stimulus were presented simultaneously. Against the background of the available studies, these results support an account according to which speakers tend to avoid concurrent response selection, but can engage in other types of concurrent processing, such as task choices. Copyright © 2015 Elsevier B.V. All rights reserved.

Reward Sensitivity and Waiting Impulsivity: Shift towards Reward Valuation away from Action Control

PubMed Central

Mechelmans, Daisy J; Strelchuk, Daniela; Doñamayor, Nuria; Banca, Paula; Robbins, Trevor W; Baek, Kwangyeol

2017-01-01

Abstract Background Impulsivity and reward expectancy are commonly interrelated. Waiting impulsivity, measured using the rodent 5-Choice Serial Reaction Time task, predicts compulsive cocaine seeking and sign (or cue) tracking. Here, we assess human waiting impulsivity using a novel translational task, the 4-Choice Serial Reaction Time task, and the relationship with reward cues. Methods Healthy volunteers (n=29) performed the monetary incentive delay task as a functional MRI study where subjects observe a cue predicting reward (cue) and wait to respond for high (£5), low (£1), or no reward. Waiting impulsivity was tested with the 4-Choice Serial Reaction Time task. Results For high reward prospects (£5, no reward), greater waiting impulsivity on the 4-CSRT correlated with greater medial orbitofrontal cortex and lower supplementary motor area activity to cues. In response to high reward cues, greater waiting impulsivity was associated with greater subthalamic nucleus connectivity with orbitofrontal cortex and greater subgenual cingulate connectivity with anterior insula, but decreased connectivity with regions implicated in action selection and preparation. Conclusion These findings highlight a shift towards regions implicated in reward valuation and a shift towards compulsivity away from higher level motor preparation and action selection and response. We highlight the role of reward sensitivity and impulsivity, mechanisms potentially linking human waiting impulsivity with incentive approach and compulsivity, theories highly relevant to disorders of addiction. PMID:29020291

Neuronal responses to target onset in oculomotor and somatomotor parietal circuits differ markedly in a choice task.

PubMed

Kubanek, J; Wang, C; Snyder, L H

2013-11-01

We often look at and sometimes reach for visible targets. Looking at a target is fast and relatively easy. By comparison, reaching for an object is slower and is associated with a larger cost. We hypothesized that, as a result of these differences, abrupt visual onsets may drive the circuits involved in saccade planning more directly and with less intermediate regulation than the circuits involved in reach planning. To test this hypothesis, we recorded discharge activity of neurons in the parietal oculomotor system (area LIP) and in the parietal somatomotor system (area PRR) while monkeys performed a visually guided movement task and a choice task. We found that in the visually guided movement task LIP neurons show a prominent transient response to target onset. PRR neurons also show a transient response, although this response is reduced in amplitude, is delayed, and has a slower rise time compared with LIP. A more striking difference is observed in the choice task. The transient response of PRR neurons is almost completely abolished and replaced with a slow buildup of activity, while the LIP response is merely delayed and reduced in amplitude. Our findings suggest that the oculomotor system is more closely and obligatorily coupled to the visual system, whereas the somatomotor system operates in a more discriminating manner.

Evidence for higher reaction time variability for children with ADHD on a range of cognitive tasks including reward and event rate manipulations

PubMed Central

Epstein, Jeffery N.; Langberg, Joshua M.; Rosen, Paul J.; Graham, Amanda; Narad, Megan E.; Antonini, Tanya N.; Brinkman, William B.; Froehlich, Tanya; Simon, John O.; Altaye, Mekibib

2012-01-01

Objective The purpose of the research study was to examine the manifestation of variability in reaction times (RT) in children with Attention Deficit Hyperactivity Disorder (ADHD) and to examine whether RT variability presented differently across a variety of neuropsychological tasks, was present across the two most common ADHD subtypes, and whether it was affected by reward and event rate (ER) manipulations. Method Children with ADHD-Combined Type (n=51), ADHD-Predominantly Inattentive Type (n=53) and 47 controls completed five neuropsychological tasks (Choice Discrimination Task, Child Attentional Network Task, Go/No-Go task, Stop Signal Task, and N-back task), each allowing trial-by-trial assessment of reaction times. Multiple indicators of RT variability including RT standard deviation, coefficient of variation and ex-Gaussian tau were used. Results Children with ADHD demonstrated greater RT variability than controls across all five tasks as measured by the ex-Gaussian indicator tau. There were minimal differences in RT variability across the ADHD subtypes. Children with ADHD also had poorer task accuracy than controls across all tasks except the Choice Discrimination task. Although ER and reward manipulations did affect children’s RT variability and task accuracy, these manipulations largely did not differentially affect children with ADHD compared to controls. RT variability and task accuracy were highly correlated across tasks. Removing variance attributable to RT variability from task accuracy did not appreciably affect between-group differences in task accuracy. Conclusions High RT variability is a ubiquitous and robust phenomenon in children with ADHD. PMID:21463041

Dynamic Response-by-Response Models of Matching Behavior in Rhesus Monkeys

PubMed Central

Lau, Brian; Glimcher, Paul W

2005-01-01

We studied the choice behavior of 2 monkeys in a discrete-trial task with reinforcement contingencies similar to those Herrnstein (1961) used when he described the matching law. In each session, the monkeys experienced blocks of discrete trials at different relative-reinforcer frequencies or magnitudes with unsignalled transitions between the blocks. Steady-state data following adjustment to each transition were well characterized by the generalized matching law; response ratios undermatched reinforcer frequency ratios but matched reinforcer magnitude ratios. We modelled response-by-response behavior with linear models that used past reinforcers as well as past choices to predict the monkeys' choices on each trial. We found that more recently obtained reinforcers more strongly influenced choice behavior. Perhaps surprisingly, we also found that the monkeys' actions were influenced by the pattern of their own past choices. It was necessary to incorporate both past reinforcers and past choices in order to accurately capture steady-state behavior as well as the fluctuations during block transitions and the response-by-response patterns of behavior. Our results suggest that simple reinforcement learning models must account for the effects of past choices to accurately characterize behavior in this task, and that models with these properties provide a conceptual tool for studying how both past reinforcers and past choices are integrated by the neural systems that generate behavior. PMID:16596980

Rethinking volitional control over task choice in multitask environments: use of a stimulus set selection strategy in voluntary task switching.

PubMed

Arrington, Catherine M; Weaver, Starla M

2015-01-01

Under conditions of volitional control in multitask environments, subjects may engage in a variety of strategies to guide task selection. The current research examines whether subjects may sometimes use a top-down control strategy of selecting a task-irrelevant stimulus dimension, such as location, to guide task selection. We term this approach a stimulus set selection strategy. Using a voluntary task switching procedure, subjects voluntarily switched between categorizing letter and number stimuli that appeared in two, four, or eight possible target locations. Effects of stimulus availability, manipulated by varying the stimulus onset asynchrony between the two target stimuli, and location repetition were analysed to assess the use of a stimulus set selection strategy. Considered across position condition, Experiment 1 showed effects of both stimulus availability and location repetition on task choice suggesting that only in the 2-position condition, where selection based on location always results in a target at the selected location, subjects may have been using a stimulus set selection strategy on some trials. Experiment 2 replicated and extended these findings in a visually more cluttered environment. These results indicate that, contrary to current models of task selection in voluntary task switching, the top-down control of task selection may occur in the absence of the formation of an intention to perform a particular task.

A prework assessment of task preferences among adults with autism beginning a supported job.

PubMed

Lattimore, L Perry; Parsons, Marsha B; Reid, Dennis H

2002-01-01

A prework paired-task assessment was evaluated for identifying work preferences among 3 adults with autism beginning a supported job. When the workers began the job, choices were provided between more and less preferred tasks (determined by previous assessment). Results supported the assessment for identifying single task preferences, but did not reveal preferences of 2 workers for alternate tasks. Results are discussed in terms of evaluating other prework assessments that may reveal task-alternation preferences.

Driving while using a smartphone-based mobility application: Evaluating the impact of three multi-choice user interfaces on visual-manual distraction.

PubMed

Louveton, N; McCall, R; Koenig, V; Avanesov, T; Engel, T

2016-05-01

Innovative in-car applications provided on smartphones can deliver real-time alternative mobility choices and subsequently generate visual-manual demand. Prior studies have found that multi-touch gestures such as kinetic scrolling are problematic in this respect. In this study we evaluate three prototype tasks which can be found in common mobile interaction use-cases. In a repeated-measures design, 29 participants interacted with the prototypes in a car-following task within a driving simulator environment. Task completion, driving performance and eye gaze have been analysed. We found that the slider widget used in the filtering task was too demanding and led to poor performance, while kinetic scrolling generated a comparable amount of visual distraction despite it requiring a lower degree of finger pointing accuracy. We discuss how to improve continuous list browsing in a dual-task context. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Simulated thought insertion: Influencing the sense of agency using deception and magic.

PubMed

Olson, Jay A; Landry, Mathieu; Appourchaux, Krystèle; Raz, Amir

2016-07-01

In order to study the feeling of control over decisions, we told 60 participants that a neuroimaging machine could read and influence their thoughts. While inside a mock brain scanner, participants chose arbitrary numbers in two similar tasks. In the Mind-Reading Task, the scanner appeared to guess the participants' numbers; in the Mind-Influencing Task, it appeared to influence their choice of numbers. We predicted that participants would feel less voluntary control over their decisions when they believed that the scanner was influencing their choices. As predicted, participants felt less control and made slower decisions in the Mind-Influencing Task compared to the Mind-Reading Task. A second study replicated these findings. Participants' experience of the ostensible influence varied, with some reporting an unknown source directing them towards specific numbers. This simulated thought insertion paradigm can therefore influence feelings of voluntary control and may help model symptoms of mental disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

Formal Derivation of Lotka-Volterra-Haken Amplitude Equations of Task-Related Brain Activity in Multiple, Consecutively Performed Tasks

NASA Astrophysics Data System (ADS)

Frank, T. D.

The Lotka-Volterra-Haken equations have been frequently used in ecology and pattern formation. Recently, the equations have been proposed by several research groups as amplitude equations for task-related patterns of brain activity. In this theoretical study, the focus is on the circular causality aspect of pattern formation systems as formulated within the framework of synergetics. Accordingly, the stable modes of a pattern formation system inhibit the unstable modes, whereas the unstable modes excite the stable modes. Using this circular causality principle it is shown that under certain conditions the Lotka-Volterra-Haken amplitude equations can be derived from a general model of brain activity akin to the Wilson-Cowan model. The model captures the amplitude dynamics for brain activity patterns in experiments involving several consecutively performed multiple-choice tasks. This is explicitly demonstrated for two-choice tasks involving grasping and walking. A comment on the relevance of the theoretical framework for clinical psychology and schizophrenia is given as well.

Detecting Latent Heterogeneity

ERIC Educational Resources Information Center

Pearl, Judea

2017-01-01

We address the task of determining, from statistical averages alone, whether a population under study consists of several subpopulations, unknown to the investigator, each responding to a given treatment markedly differently. We show that such determination is feasible in three cases: (1) randomized trials with binary treatments, (2) models where…

NetNorM: Capturing cancer-relevant information in somatic exome mutation data with gene networks for cancer stratification and prognosis.

PubMed

Le Morvan, Marine; Zinovyev, Andrei; Vert, Jean-Philippe

2017-06-01

Genome-wide somatic mutation profiles of tumours can now be assessed efficiently and promise to move precision medicine forward. Statistical analysis of mutation profiles is however challenging due to the low frequency of most mutations, the varying mutation rates across tumours, and the presence of a majority of passenger events that hide the contribution of driver events. Here we propose a method, NetNorM, to represent whole-exome somatic mutation data in a form that enhances cancer-relevant information using a gene network as background knowledge. We evaluate its relevance for two tasks: survival prediction and unsupervised patient stratification. Using data from 8 cancer types from The Cancer Genome Atlas (TCGA), we show that it improves over the raw binary mutation data and network diffusion for these two tasks. In doing so, we also provide a thorough assessment of somatic mutations prognostic power which has been overlooked by previous studies because of the sparse and binary nature of mutations.

Improved opponent color local binary patterns: an effective local image descriptor for color texture classification

NASA Astrophysics Data System (ADS)

Bianconi, Francesco; Bello-Cerezo, Raquel; Napoletano, Paolo

2018-01-01

Texture classification plays a major role in many computer vision applications. Local binary patterns (LBP) encoding schemes have largely been proven to be very effective for this task. Improved LBP (ILBP) are conceptually simple, easy to implement, and highly effective LBP variants based on a point-to-average thresholding scheme instead of a point-to-point one. We propose the use of this encoding scheme for extracting intra- and interchannel features for color texture classification. We experimentally evaluated the resulting improved opponent color LBP alone and in concatenation with the ILBP of the local color contrast map on a set of image classification tasks over 9 datasets of generic color textures and 11 datasets of biomedical textures. The proposed approach outperformed other grayscale and color LBP variants in nearly all the datasets considered and proved competitive even against image features from last generation convolutional neural networks, particularly for the classification of biomedical images.

Chromatic characterization of ion-exchanged glass binary phase plates for mode-division multiplexing.

PubMed

Prieto-Blanco, Xesús; Montero-Orille, Carlos; Moreno, Vicente; Mateo, Eduardo F; Liñares, Jesús

2015-04-10

Mode-division multiplexing (MDM) in few-mode fibers is regarded as a promising candidate to increase optical network capacity. A fundamental element for MDM is a modal transformer to LP modes which can be implemented in a free-space basis by using multiregion phase plates, that is, LP plates. Likewise, several wavelengths have to be used due to wavelength multiplexing purposes, optical amplification tasks, and so on. In this work we show that efficient monolithic binary phase plates for different wavelengths can be fabricated by ion-exchange in glass and used for MDM tasks. We introduce an optical characterization method of the chromatic properties of such phase plates which combines the inverse Wentzel-Kramers-Brillouin (IWKB) together with Mach-Zehnder and Michelson-based interferometric techniques. The interferometric method provides a measurement of the phase step for several wavelengths, which characterizes the chromatic properties of the phase plate. Consequently, it is shown that the IWKB method allows us to design and characterize the phase plates in an easy and fast way.

NetNorM: Capturing cancer-relevant information in somatic exome mutation data with gene networks for cancer stratification and prognosis

PubMed Central

2017-01-01

Genome-wide somatic mutation profiles of tumours can now be assessed efficiently and promise to move precision medicine forward. Statistical analysis of mutation profiles is however challenging due to the low frequency of most mutations, the varying mutation rates across tumours, and the presence of a majority of passenger events that hide the contribution of driver events. Here we propose a method, NetNorM, to represent whole-exome somatic mutation data in a form that enhances cancer-relevant information using a gene network as background knowledge. We evaluate its relevance for two tasks: survival prediction and unsupervised patient stratification. Using data from 8 cancer types from The Cancer Genome Atlas (TCGA), we show that it improves over the raw binary mutation data and network diffusion for these two tasks. In doing so, we also provide a thorough assessment of somatic mutations prognostic power which has been overlooked by previous studies because of the sparse and binary nature of mutations. PMID:28650955

The Case of Rosie: An Adlerian Response.

ERIC Educational Resources Information Center

Powers, Robert L.; Griffith, Jane

1993-01-01

Responds to case of Rosie, 35-year-old unmarried community college student struggling with decisions regarding career choice and desire to marry and become a homemaker. Employs Individual Psychology, especially in addressing Rosie's stated sense of failure in each of three life tasks identified by Adler: social task of friendship; tasks of love…

The Impact of Choice on EFL Students' Motivation and Engagement with L2 Vocabulary Learning

ERIC Educational Resources Information Center

Wang, Han-Chung; Huang, Hung-Tzu; Hsu, Chun-Chieh

2015-01-01

The current study investigates EFL college learners' motivation and engagement during English vocabulary learning tasks. By adopting self-determination theory (SDT; Deci & Ryan, 1985, 2000), the study looked into the impact of autonomy on college students' task motivation and engagement with vocabulary learning tasks and their general English…

Advanced Marketing Core Curriculum. Test Items and Assessment Techniques.

ERIC Educational Resources Information Center

Smith, Clifton L.; And Others

This document contains duties and tasks, multiple-choice test items, and other assessment techniques for Missouri's advanced marketing core curriculum. The core curriculum begins with a list of 13 suggested textbook resources. Next, nine duties with their associated tasks are given. Under each task appears one or more citations to appropriate…

Task driven optimal leg trajectories in insect-scale legged microrobots

NASA Astrophysics Data System (ADS)

Doshi, Neel; Goldberg, Benjamin; Jayaram, Kaushik; Wood, Robert

Origami inspired layered manufacturing techniques and 3D-printing have enabled the development of highly articulated legged robots at the insect-scale, including the 1.43g Harvard Ambulatory MicroRobot (HAMR). Research on these platforms has expanded its focus from manufacturing aspects to include design optimization and control for application-driven tasks. Consequently, the choice of gait selection, body morphology, leg trajectory, foot design, etc. have become areas of active research. HAMR has two controlled degrees-of-freedom per leg, making it an ideal candidate for exploring leg trajectory. We will discuss our work towards optimizing HAMR's leg trajectories for two different tasks: climbing using electroadhesives and level ground running (5-10 BL/s). These tasks demonstrate the ability of single platform to adapt to vastly different locomotive scenarios: quasi-static climbing with controlled ground contact, and dynamic running with un-controlled ground contact. We will utilize trajectory optimization methods informed by existing models and experimental studies to determine leg trajectories for each task. We also plan to discuss how task specifications and choice of objective function have contributed to the shape of these optimal leg trajectories.

Indirect Measurement of Sexual Orientation: Comparison of the Implicit Relational Assessment Procedure, Viewing Time, and Choice Reaction Time Tasks.

PubMed

Rönspies, Jelena; Schmidt, Alexander F; Melnikova, Anna; Krumova, Rosina; Zolfagari, Asadeh; Banse, Rainer

2015-07-01

The present study was conducted to validate an adaptation of the Implicit Relational Assessment Procedure (IRAP) as an indirect latency-based measure of sexual orientation. Furthermore, reliability and criterion validity of the IRAP were compared to two established indirect measures of sexual orientation: a Choice Reaction Time task (CRT) and a Viewing Time (VT) task. A sample of 87 heterosexual and 35 gay men completed all three indirect measures in an online study. The IRAP and the VT predicted sexual orientation nearly perfectly. Both measures also showed a considerable amount of convergent validity. Reliabilities (internal consistencies) reached satisfactory levels. In contrast, the CRT did not tap into sexual orientation in the present study. In sum, the VT measure performed best, with the IRAP showing only slightly lower reliability and criterion validity, whereas the CRT did not yield any evidence of reliability or criterion validity in the present research. The results were discussed in the light of specific task properties of the indirect latency-based measures (task-relevance vs. task-irrelevance).

Attention.

PubMed

Callahan, Patrick M; Terry, Alvin V

2015-01-01

The ability to focus one's attention on important environmental stimuli while ignoring irrelevant stimuli is fundamental to human cognition and intellectual function. Attention is inextricably linked to perception, learning and memory, and executive function; however, it is often impaired in a variety of neuropsychiatric disorders, including Alzheimer's disease, schizophrenia, depression, and attention deficit hyperactivity disorder (ADHD). Accordingly, attention is considered as an important therapeutic target in these disorders. The purpose of this chapter is to provide an overview of the most common behavioral paradigms of attention that have been used in animals (particularly rodents) and to review the literature where these tasks have been employed to elucidate neurobiological substrates of attention as well as to evaluate novel pharmacological agents for their potential as treatments for disorders of attention. These paradigms include two tasks of sustained attention that were developed as rodent analogues of the human Continuous Performance Task (CPT), the Five-Choice Serial Reaction Time Task (5-CSRTT) and the more recently introduced Five-Choice Continuous Performance Task (5C-CPT), and the Signal Detection Task (SDT) which was designed to emphasize temporal components of attention.

Differences between racing and non-racing drivers: A simulator study using eye-tracking

PubMed Central

de Groot, Stefan; Happee, Riender; de Winter, Joost C. F.

2017-01-01

Motorsport has developed into a professional international competition. However, limited research is available on the perceptual and cognitive skills of racing drivers. By means of a racing simulator, we compared the driving performance of seven racing drivers with ten non-racing drivers. Participants were tasked to drive the fastest possible lap time. Additionally, both groups completed a choice reaction time task and a tracking task. Results from the simulator showed faster lap times, higher steering activity, and a more optimal racing line for the racing drivers than for the non-racing drivers. The non-racing drivers’ gaze behavior corresponded to the tangent point model, whereas racing drivers showed a more variable gaze behavior combined with larger head rotations while cornering. Results from the choice reaction time task and tracking task showed no statistically significant difference between the two groups. Our results are consistent with the current consensus in sports sciences in that task-specific differences exist between experts and novices while there are no major differences in general cognitive and motor abilities. PMID:29121090

When pain meets … pain-related choice behavior and pain perception in different goal conflict situations.

PubMed

Schrooten, Martien G S; Wiech, Katja; Vlaeyen, Johan W S

2014-11-01

Individuals in pain often face the choice between avoiding pain and pursuing other equally valued goals. However, little is known about pain-related choice behavior and pain perception in goal conflict situations. Seventy-eight healthy volunteers performed a computerized task requiring repeated choices between incompatible options, differing in their effect on probability to receive painful stimulation and money. Depending on group assignment, participants chose between increased pain probability versus decreased money probability (avoidance-avoidance conflict situation); decreased pain probability versus increased money probability (approach-approach conflict situation); or decrease versus increase in both probabilities (double approach/avoidance conflict situation). During the choice task, participants rated painfulness, unpleasantness, threat, and fearfulness associated with the painful stimulation and how they felt. Longer choice latency and more choice switching were associated with higher retrospective ratings of conflict and of decision difficulty, and more equal importance placed on pain avoidance and earning money. Groups did not differ in choice behavior, pain stimulus ratings, or affect. Across groups, longer choice latencies were nonsignificantly associated with higher pain, unpleasantness, threat, and fearfulness. In the avoidance-avoidance group, more choice switching was associated with higher pain-related threat and fearfulness, and with more negative affect. These results of this study suggest that associations between choice behaviors, pain perception, and affect depend on conflict situation. We present a first experimental demonstration of the relationship between pain-related choice behaviors, pain, and affect in different goal conflict situations. This experimental approach allows us to examine these relationships in a controlled fashion. Better understanding of pain-related goal conflicts and their resolution may lead to more effective pain treatment. Copyright © 2014 American Pain Society. Published by Elsevier Inc. All rights reserved.

Serial binary interval ratios improve rhythm reproduction.

PubMed

Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

2013-01-01

Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

Serial binary interval ratios improve rhythm reproduction

PubMed Central

Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

2013-01-01

Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception. PMID:23964258

Evaluating choices by single neurons in the frontal lobe: outcome value encoded across multiple decision variables

PubMed Central

Kennerley, Steven W.; Wallis, Jonathan D.

2009-01-01

Damage to the frontal lobe can cause severe decision-making impairments. A mechanism that may underlie this is that neurons in the frontal cortex encode many variables that contribute to the valuation of a choice, such as its costs, benefits and probability of success. However, optimal decision-making requires that one considers these variables, not only when faced with the choice, but also when evaluating the outcome of the choice, in order to adapt future behaviour appropriately. To examine the role of the frontal cortex in encoding the value of different choice outcomes, we simultaneously recorded the activity of multiple single neurons in the anterior cingulate cortex (ACC), orbitofrontal cortex (OFC) and lateral prefrontal cortex (LPFC) while subjects evaluated the outcome of choices involving manipulations of probability, payoff and cost. Frontal neurons encoded many of the parameters that enabled the calculation of the value of these variables, including the onset and offset of reward and the amount of work performed, and often encoded the value of outcomes across multiple decision variables. In addition, many neurons encoded both the predicted outcome during the choice phase of the task as well as the experienced outcome in the outcome phase of the task. These patterns of selectivity were more prevalent in ACC relative to OFC and LPFC. These results support a role for the frontal cortex, principally ACC, in selecting between choice alternatives and evaluating the outcome of that selection thereby ensuring that choices are optimal and adaptive. PMID:19453638

Petri nets as a modeling tool for discrete concurrent tasks of the human operator. [describing sequential and parallel demands on human operators

NASA Technical Reports Server (NTRS)

Schumacher, W.; Geiser, G.

1978-01-01

The basic concepts of Petri nets are reviewed as well as their application as the fundamental model of technical systems with concurrent discrete events such as hardware systems and software models of computers. The use of Petri nets is proposed for modeling the human operator dealing with concurrent discrete tasks. Their properties useful in modeling the human operator are discussed and practical examples are given. By means of and experimental investigation of binary concurrent tasks which are presented in a serial manner, the representation of human behavior by Petri nets is demonstrated.

Students' Interpretations of Writing Tasks: A Case Study.

ERIC Educational Resources Information Center

Kirsch, Gesa

1988-01-01

Argues that successful interpretation of writing tasks demands writers' authority, confidence, and knowledge of rhetorical choices, allowing them to take charge of their own writing rather than catering to the imagined demands of a teacher. (RS)

On the differentiation of N2 components in an appetitive choice task: evidence for the revised Reinforcement Sensitivity Theory.

PubMed

Leue, Anja; Chavanon, Mira-Lynn; Wacker, Jan; Stemmler, Gerhard

2009-11-01

Task- and personality-related modulations of the N2 were probed within the framework of the revised Reinforcement Sensitivity Theory (RST). Using an appetitive choice task, we investigated 58 students with extreme scores on the behavioral inhibition system and behavioral approach system (BIS/BAS) scales. The baseline-to-peak N2 amplitude was sensitive to the strength of decision conflict and demonstrated RST-related personality differences. In addition to the baseline N2 amplitude, temporal PCA results suggested two N2 components accounting for a laterality effect and capturing different N2 patterns for BIS/BAS groups with increasing conflict level. Evidence for RST-related personality differences was obtained for baseline-to-peak N2 and tPCA components in the present task. The results support the RST prediction that BAS sensitivity modulates conflict processing and confirm the cognitive-motivational conflict concept of RST.

Theory of mind and central coherence in adults with high-functioning autism or Asperger syndrome.

PubMed

Beaumont, Renae; Newcombe, Peter

2006-07-01

The study investigated theory of mind and central coherence abilities in adults with high-functioning autism (HFA) or Asperger syndrome (AS) using naturalistic tasks. Twenty adults with HFA/AS correctly answered significantly fewer theory of mind questions than 20 controls on a forced-choice response task. On a narrative task, there were no differences in the proportion of mental state words between the two groups, although the participants with HFA/AS were less inclined to provide explanations for characters' mental states. No between-group differences existed on the central coherence questions of the forced-choice response task, and the participants with HFA/AS included an equivalent proportion of explanations for non-mental state phenomena in their narratives as did controls. These results support the theory of mind deficit account of autism spectrum disorders, and suggest that difficulties in mental state attribution cannot be exclusively attributed to weak central coherence.

Eurasian jays do not copy the choices of conspecifics, but they do show evidence of stimulus enhancement

PubMed Central

Miller, Rachael; Lister, Katherine; Clayton, Nicola S.

2016-01-01

Corvids (birds in the crow family) are hypothesised to have a general cognitive tool-kit because they show a wide range of transferrable skills across social, physical and temporal tasks, despite differences in socioecology. However, it is unknown whether relatively asocial corvids differ from social corvids in their use of social information in the context of copying the choices of others, because only one such test has been conducted in a relatively asocial corvid. We investigated whether relatively asocial Eurasian jays (Garrulus glandarius) use social information (i.e., information made available by others). Previous studies have indicated that jays attend to social context in their caching and mate provisioning behaviour; however, it is unknown whether jays copy the choices of others. We tested the jays in two different tasks varying in difficulty, where social corvid species have demonstrated social information use in both tasks. Firstly, an object-dropping task was conducted requiring objects to be dropped down a tube to release a food reward from a collapsible platform, which corvids can learn through explicit training. Only one rook and one New Caledonian crow have learned the task using social information from a demonstrator. Secondly, we tested the birds on a simple colour discrimination task, which should be easy to solve, because it has been shown that corvids can make colour discriminations. Using the same colour discrimination task in a previous study, all common ravens and carrion crows copied the demonstrator. After observing a conspecific demonstrator, none of the jays solved the object-dropping task, though all jays were subsequently able to learn to solve the task in a non-social situation through explicit training, and jays chose the demonstrated colour at chance levels. Our results suggest that social and relatively asocial corvids differ in social information use, indicating that relatively asocial species may have secondarily lost this ability due to lack of selection pressure from an asocial environment. PMID:27920957

Sensory and motoric influences on attention dynamics during standing balance recovery in young and older adults.

PubMed

Redfern, Mark S; Chambers, April J; Jennings, J Richard; Furman, Joseph M

2017-08-01

This study investigated the impact of attention on the sensory and motor actions during postural recovery from underfoot perturbations in young and older adults. A dual-task paradigm was used involving disjunctive and choice reaction time (RT) tasks to auditory and visual stimuli at different delays from the onset of two types of platform perturbations (rotations and translations). The RTs were increased prior to the perturbation (preparation phase) and during the immediate recovery response (response initiation) in young and older adults, but this interference dissipated rapidly after the perturbation response was initiated (<220 ms). The sensory modality of the RT task impacted the results with interference being greater for the auditory task compared to the visual task. As motor complexity of the RT task increased (disjunctive versus choice) there was greater interference from the perturbation. Finally, increasing the complexity of the postural perturbation by mixing the rotational and translational perturbations together increased interference for the auditory RT tasks, but did not affect the visual RT responses. These results suggest that sensory and motoric components of postural control are under the influence of different dynamic attentional processes.

Free classification of regional dialects of American English.

PubMed

Clopper, Cynthia G; Pisoni, David B

2007-07-01

Recent studies have found that naïve listeners perform poorly in forced-choice dialect categorization tasks. However, the listeners' error patterns in these tasks reveal systematic confusions between phonologically similar dialects. In the present study, a free classification procedure was used to measure the perceptual similarity structure of regional dialect variation in the United States. In two experiments, participants listened to a set of short English sentences produced by male talkers only (Experiment 1) and by male and female talkers (Experiment 2). The listeners were instructed to group the talkers by regional dialect into as many groups as they wanted with as many talkers in each group as they wished. Multidimensional scaling analyses of the data revealed three primary dimensions of perceptual similarity (linguistic markedness, geography, and gender). In addition, a comparison of the results obtained from the free classification task to previous results using the same stimulus materials in six-alternative forced-choice categorization tasks revealed that response biases in the six-alternative task were reduced or eliminated in the free classification task. Thus, the results obtained with the free classification task in the current study provided further evidence that the underlying structure of perceptual dialect category representations reflects important linguistic and sociolinguistic factors.

Impaired insight in cocaine addiction: laboratory evidence and effects on cocaine-seeking behaviour

PubMed Central

Maloney, Thomas; Parvaz, Muhammad A.; Alia-Klein, Nelly; Woicik, Patricia A.; Telang, Frank; Wang, Gene-Jack; Volkow, Nora D.; Goldstein, Rita Z.

2010-01-01

Neuropsychiatric disorders are often characterized by impaired insight into behaviour. Such an insight deficit has been suggested, but never directly tested, in drug addiction. Here we tested for the first time this impaired insight hypothesis in drug addiction, and examined its potential association with drug-seeking behaviour. We also tested potential modulation of these effects by cocaine urine status, an individual difference known to impact underlying cognitive functions and prognosis. Sixteen cocaine addicted individuals testing positive for cocaine in urine, 26 cocaine addicted individuals testing negative for cocaine in urine, and 23 healthy controls completed a probabilistic choice task that assessed objective preference for viewing four types of pictures (pleasant, unpleasant, neutral and cocaine). This choice task concluded by asking subjects to report their most selected picture type; correspondence between subjects’ self-reports with their objective choice behaviour provided our index of behavioural insight. Results showed that the urine positive cocaine subjects exhibited impaired insight into their own choice behaviour compared with healthy controls; this same study group also selected the most cocaine pictures (and fewest pleasant pictures) for viewing. Importantly, however, it was the urine negative cocaine subjects whose behaviour was most influenced by insight, such that impaired insight in this subgroup only was associated with higher cocaine-related choice on the task and more severe actual cocaine use. These findings suggest that interventions to enhance insight may decrease drug-seeking behaviour, especially in urine negative cocaine subjects, potentially to improve their longer-term clinical outcomes. PMID:20395264

Temporal Discounting and Inter-Temporal Choice in Rhesus Monkeys

PubMed Central

Hwang, Jaewon; Kim, Soyoun; Lee, Daeyeol

2009-01-01

Humans and animals are more likely to take an action leading to an immediate reward than actions with delayed rewards of similar magnitudes. Although such devaluation of delayed rewards has been almost universally described by hyperbolic discount functions, the rate of this temporal discounting varies substantially among different animal species. This might be in part due to the differences in how the information about reward is presented to decision makers. In previous animal studies, reward delays or magnitudes were gradually adjusted across trials, so the animals learned the properties of future rewards from the rewards they waited for and consumed previously. In contrast, verbal cues have been used commonly in human studies. In the present study, rhesus monkeys were trained in a novel inter-temporal choice task in which the magnitude and delay of reward were indicated symbolically using visual cues and varied randomly across trials. We found that monkeys could extract the information about reward delays from visual symbols regardless of the number of symbols used to indicate the delay. The rate of temporal discounting observed in the present study was comparable to the previous estimates in other mammals, and the animal's choice behavior was largely consistent with hyperbolic discounting. Our results also suggest that the rate of temporal discounting might be influenced by contextual factors, such as the novelty of the task. The flexibility furnished by this new inter-temporal choice task might be useful for future neurobiological investigations on inter-temporal choice in non-human primates. PMID:19562091

Fatigue modulates dopamine availability and promotes flexible choice reversals during decision making.

PubMed

Iodice, Pierpaolo; Ferrante, Claudio; Brunetti, Luigi; Cabib, Simona; Protasi, Feliciano; Walton, Mark E; Pezzulo, Giovanni

2017-04-03

During decisions, animals balance goal achievement and effort management. Despite physical exercise and fatigue significantly affecting the levels of effort that an animal exerts to obtain a reward, their role in effort-based choice and the underlying neurochemistry are incompletely known. In particular, it is unclear whether fatigue influences decision (cost-benefit) strategies flexibly or only post-decision action execution and learning. To answer this question, we trained mice on a T-maze task in which they chose between a high-cost, high-reward arm (HR), which included a barrier, and a low-cost, low-reward arm (LR), with no barrier. The animals were parametrically fatigued immediately before the behavioural tasks by running on a treadmill. We report a sharp choice reversal, from the HR to LR arm, at 80% of their peak workload (PW), which was temporary and specific, as the mice returned to choose the HC when the animals were successively tested at 60% PW or in a two-barrier task. These rapid reversals are signatures of flexible choice. We also observed increased subcortical dopamine levels in fatigued mice: a marker of individual bias to use model-based control in humans. Our results indicate that fatigue levels can be incorporated in flexible cost-benefits computations that improve foraging efficiency.

Dissociable contributions of anterior cingulate cortex and basolateral amygdala on a rodent cost/benefit decision-making task of cognitive effort.

PubMed

Hosking, Jay G; Cocker, Paul J; Winstanley, Catharine A

2014-06-01

Personal success often requires the choice to expend greater effort for larger rewards, and deficits in such effortful decision making accompany a number of illnesses including depression, schizophrenia, and attention-deficit/hyperactivity disorder. Animal models have implicated brain regions such as the basolateral amygdala (BLA) and anterior cingulate cortex (ACC) in physical effort-based choice, but disentangling the unique contributions of these two regions has proven difficult, and effort demands in industrialized society are predominantly cognitive in nature. Here we utilize the rodent cognitive effort task (rCET), a modification of the five-choice serial reaction-time task, wherein animals can choose to expend greater visuospatial attention to obtain larger sucrose rewards. Temporary inactivation (via baclofen-muscimol) of BLA and ACC showed dissociable effects: BLA inactivation caused hard-working rats to 'slack off' and 'slacker' rats to work harder, whereas ACC inactivation caused all animals to reduce willingness to expend mental effort. Furthermore, BLA inactivation increased the time needed to make choices, whereas ACC inactivation increased motor impulsivity. These data illuminate unique contributions of BLA and ACC to effort-based decision making, and imply overlapping yet distinct circuitry for cognitive vs physical effort. Our understanding of effortful decision making may therefore require expanding our models beyond purely physical costs.

Quality of public information matters in mate-choice copying in female zebra finches.

PubMed

Kniel, Nina; Schmitz, Jennifer; Witte, Klaudia

2015-01-01

Mate-choice copying is a form of social learning in which an individual gains information about potential mates by observing conspecifics. However, it is still unknown what kind of information drives the decision of an individual to copy the mate choice of others. Among zebra finches (Taeniopygia guttata castanotis), only females (not males) copy the mate choice of others. We tested female zebra finches in a binary choice test where they, first, could choose between two males of different phenotypes: one unadorned male and one male artificially adorned with a red feather on the forehead. After this mate-choice test, females could observe a single unadorned male and a pair of zebra finches, i.e. a wild-type female and her adorned mate. Pair interactions were either restricted to acoustic and visual communication (clear glass screen between pair mates) or acoustic communication alone (opaque screen between pair mates). After the observation period, females could again choose between new males of the two phenotypes in a second mate-choice test. In experiments with a clear glass screen, time spent with the respective males changed between the two mate-choice tests, and females preferred adorned over unadorned males during the second mate-choice test. In experiments with an opaque screen, time spent with the respective males did not change between the two mate-choice tests, although females lost an initial preference for unadorned males. Our results demonstrate that the quality of the received public information (visual and acoustic interaction of the observed pair) influences mate-choice copying in female zebra finches.

Analog Computer-Aided Detection (CAD) information can be more effective than binary marks

PubMed Central

Cunningham, Corbin A.; Drew, Trafton; Wolfe, Jeremy M.

2017-01-01

In socially important visual search tasks such as baggage screening and diagnostic radiology, experts miss more targets than is desirable. Computer Aided Detection (CAD) programs have been developed specifically to help improve performance in these professional search tasks. For example, in breast cancer screening, many CAD systems are capable of detecting approximately 90% of breast cancer, with approximately 0.5 false positive detections per image. Nevertheless, benefits of CAD in clinical settings tend to be small (Birdwell, 2009) or even absent (Meziane et al., 2011; Philpotts, 2009). The marks made by a CAD system can be “Binary”, giving the same signal to any location where the signal is above some threshold. Alternatively, a CAD system present an Analog signal that reflected strength of the signal at a location. In the experiments reported here, we compare analog and binary CAD presentations using non-expert observers and artificial stimuli defined by two noisy signals: a visible color signal and an "invisible" signal that informed our simulated CAD system. We found that analog CAD generally yielded better overall performance than binary CAD. The analog benefit is similar at high and low target prevalence. Our data suggest that the form of the CAD signal can directly influence performance. Analog CAD may allow the computer to be more helpful to the searcher. PMID:27928658

Deciding on race: a diffusion model analysis of race-categorisation.

PubMed

Benton, Christopher P; Skinner, Andrew L

2015-06-01

It has long been known that a person's race can affect their decisions about people of another race; an observation that clearly taps into some deep societal issues. However, in order to behave differently in response to someone else's race, you must first categorise that person as other-race. The current study investigates the process of race-categorisation. Two groups of participants, Asian and Caucasian, rapidly classified facial images that varied from strongly Asian, through racially intermediate, to strongly Caucasian. In agreement with previous findings, there was a difference in category boundary between the two groups. Asian participants more frequently judged intermediate images as Caucasian and vice versa. We fitted a decision model, the Ratcliff diffusion model, to our two choice reaction time data. This model provides an account of the processes thought to underlie binary choice decisions. Within its architecture it has two components that could reasonably lead to a difference in race category boundary, these being evidence accumulation rate and a priori bias. The latter is the expectation or prior belief that a participant brings to the task, whilst the former indexes sensitivity to race-dependent perceptual cues. Whilst we find no good evidence for a difference in a priori bias between our two groups, we do find evidence for a difference in evidence accumulation rate. Our Asian participants were more sensitive to Caucasian cues within the images than were our Caucasian participants (and vice versa). These results support the idea that differences in perceptual sensitivity to race-defining visual characteristics drive differences in race categorisation. We propose that our findings fit with a wider view in which perceptual adaptation plays a central role in the visual processing of own and other race. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Noise exposure-response relationships established from repeated binary observations: Modeling approaches and applications.

PubMed

Schäffer, Beat; Pieren, Reto; Mendolia, Franco; Basner, Mathias; Brink, Mark

2017-05-01

Noise exposure-response relationships are used to estimate the effects of noise on individuals or a population. Such relationships may be derived from independent or repeated binary observations, and modeled by different statistical methods. Depending on the method by which they were established, their application in population risk assessment or estimation of individual responses may yield different results, i.e., predict "weaker" or "stronger" effects. As far as the present body of literature on noise effect studies is concerned, however, the underlying statistical methodology to establish exposure-response relationships has not always been paid sufficient attention. This paper gives an overview on two statistical approaches (subject-specific and population-averaged logistic regression analysis) to establish noise exposure-response relationships from repeated binary observations, and their appropriate applications. The considerations are illustrated with data from three noise effect studies, estimating also the magnitude of differences in results when applying exposure-response relationships derived from the two statistical approaches. Depending on the underlying data set and the probability range of the binary variable it covers, the two approaches yield similar to very different results. The adequate choice of a specific statistical approach and its application in subsequent studies, both depending on the research question, are therefore crucial.

Explaining LIGO's observations via isolated binary evolution with natal kicks

NASA Astrophysics Data System (ADS)

Wysocki, Daniel; Gerosa, Davide; O'Shaughnessy, Richard; Belczynski, Krzysztof; Gladysz, Wojciech; Berti, Emanuele; Kesden, Michael; Holz, Daniel E.

2018-02-01

We compare binary evolution models with different assumptions about black-hole natal kicks to the first gravitational-wave observations performed by the LIGO detectors. Our comparisons attempt to reconcile merger rate, masses, spins, and spin-orbit misalignments of all current observations with state-of-the-art formation scenarios of binary black holes formed in isolation. We estimate that black holes (BHs) should receive natal kicks at birth of the order of σ ≃200 (50 ) km /s if tidal processes do (not) realign stellar spins. Our estimate is driven by two simple factors. The natal kick dispersion σ is bounded from above because large kicks disrupt too many binaries (reducing the merger rate below the observed value). Conversely, the natal kick distribution is bounded from below because modest kicks are needed to produce a range of spin-orbit misalignments. A distribution of misalignments increases our models' compatibility with LIGO's observations, if all BHs are likely to have natal spins. Unlike related work which adopts a concrete BH natal spin prescription, we explore a range of possible BH natal spin distributions. Within the context of our models, for all of the choices of σ used here and within the context of one simple fiducial parameterized spin distribution, observations favor low BH natal spin.

The Structure of the Narcissistic Personality Inventory With Binary and Rating Scale Items.

PubMed

Boldero, Jennifer M; Bell, Richard C; Davies, Richard C

2015-01-01

Narcissistic Personality Inventory (NPI) items typically have a forced-choice format, comprising a narcissistic and a nonnarcissistic statement. Recently, some have presented the narcissistic statements and asked individuals to either indicate whether they agree or disagree that the statements are self-descriptive (i.e., a binary response format) or to rate the extent to which they agree or disagree that these statements are self-descriptive on a Likert scale (i.e., a rating response format). The current research demonstrates that when NPI items have a binary or a rating response format, the scale has a bifactor structure (i.e., the items load on a general factor and on 6 specific group factors). Indexes of factor strength suggest that the data are unidimensional enough for the NPI's general factor to be considered a measure of a narcissism latent trait. However, the rating item general factor assessed more narcissism components than the binary item one. The positive correlations of the NPI's general factor, assessed when items have a rating response format, were moderate with self-esteem, strong with a measure of narcissistic grandiosity, and weak with 2 measures of narcissistic vulnerability. Together, the results suggest that using a rating format for items enhances the information provided by the NPI.

Cross-talk free selective reconstruction of individual objects from multiplexed optical field data

NASA Astrophysics Data System (ADS)

Zea, Alejandro Velez; Barrera, John Fredy; Torroba, Roberto

2018-01-01

In this paper we present a data multiplexing method for simultaneous storage in a single package composed by several optical fields of tridimensional (3D) objects, and their individual cross-talk free retrieval. Optical field data are extracted from off axis Fourier holograms, and then sampled by multiplying them with random binary masks. The resulting sampled optical fields can be used to reconstruct the original objects. Sampling causes a loss of quality that can be controlled by the number of white pixels in the binary masks and by applying a padding procedure on the optical field data. This process can be performed using a different binary mask for each optical field, and then added to form a multiplexed package. With the adequate choice of sampling and padding, we can achieve a volume reduction in the multiplexed package over the addition of all individual optical fields. Moreover, the package can be multiplied by a binary mask to select a specific optical field, and after the reconstruction procedure, the corresponding 3D object is recovered without any cross-talk. We demonstrate the effectiveness of our proposal for data compression with a comparison with discrete cosine transform filtering. Experimental results confirm the validity of our proposal.

Improving the experience of pregnancy and childbirth for deaf people and their families.

PubMed

Sporek, Paulina

2014-04-01

Deafness is unique in that it crosses barriers of age, gender, economic status and ethnicity. It is particularly complex in the context of the 'disabled/abled binary'. Generalisation is unhelpful since impairment is individualised and manifests itself in emotional, psychological, social and physical dimensions of a person's life. The 'Deaf Nest' project aims to improve deaf users' personal experience, equality of access, choice and control over maternity care. The implementation of clear guidance, an early assessment form, effective referrals, deaf awareness study days and 'Deaf Nest' support packs will result in improved deaf access to information, the ongoing assessment of need, improved health and lifestyle choices and greater family involvement.

Development and psychometric validation of a child Racial Attitudes Index (RAI).

PubMed

Clark, Khaya D; Yovanoff, Paul; Tate, Charlotte Ursula

2017-12-01

The Racial Attitudes Index (RAI) measures a child's racial attitudes. Designed for children aged 5-9 years, the RAI is delivered over the Internet using Audio Computer Assisted Self-Interviewing (ACASI). Unlike traditional binary forced-choice instruments, the RAI uses an expanded response format permitting a more nuanced understanding of patterns of children's racial attitudes. In addition to establishing psychometric evidence of the RAI technical adequacy, hypotheses about RAI item response patterns were tested. The racial attitudes of 336 Black and White children in grades K-3 were assessed using a forced-choice instrument (Preschool Racial Attitudes Measure II) and the RAI. Findings from this study indicate measures obtained with the RAI are technically adequate, and the measure functions invariantly across racial groups. Also, patterns of children's racial attitudes measured with the RAI are more nuanced than those obtained using the forced-choice response format.

Classification image analysis: estimation and statistical inference for two-alternative forced-choice experiments

NASA Technical Reports Server (NTRS)

Abbey, Craig K.; Eckstein, Miguel P.

2002-01-01

We consider estimation and statistical hypothesis testing on classification images obtained from the two-alternative forced-choice experimental paradigm. We begin with a probabilistic model of task performance for simple forced-choice detection and discrimination tasks. Particular attention is paid to general linear filter models because these models lead to a direct interpretation of the classification image as an estimate of the filter weights. We then describe an estimation procedure for obtaining classification images from observer data. A number of statistical tests are presented for testing various hypotheses from classification images based on some more compact set of features derived from them. As an example of how the methods we describe can be used, we present a case study investigating detection of a Gaussian bump profile.

Binary fingerprints at fluctuation-enhanced sensing.

PubMed

Chang, Hung-Chih; Kish, Laszlo B; King, Maria D; Kwan, Chiman

2010-01-01

We have developed a simple way to generate binary patterns based on spectral slopes in different frequency ranges at fluctuation-enhanced sensing. Such patterns can be considered as binary "fingerprints" of odors. The method has experimentally been demonstrated with a commercial semiconducting metal oxide (Taguchi) sensor exposed to bacterial odors (Escherichia coli and Anthrax-surrogate Bacillus subtilis) and processing their stochastic signals. With a single Taguchi sensor, the situations of empty chamber, tryptic soy agar (TSA) medium, or TSA with bacteria could be distinguished with 100% reproducibility. The bacterium numbers were in the range of 2.5 × 10(4)-10(6). To illustrate the relevance for ultra-low power consumption, we show that this new type of signal processing and pattern recognition task can be implemented by a simple analog circuitry and a few logic gates with total power consumption in the microWatts range.

Effects of normal aging on memory for multiple contextual features.

PubMed

Gagnon, Sylvain; Soulard, Kathleen; Brasgold, Melissa; Kreller, Joshua

2007-08-01

Twenty-four younger (18-35 years) and 24 older adult participants (65 or older) were exposed to three experimental conditions involving the memorization words and their associated contextual features, with contextual feature complexity increasing from Conditions 1 to 3. In Condition 1, words presented varied only on one binary feature (color, size, or character), while in Conditions 2 and 3, words presented varied on two and three binary features, respectively. Each condition was carried out as follows: (1) learning of a word list; (2) encoding of words and their contextual features; (3) delay; and (4) memory for contextual features through a discrimination task. Results indicated that young adults discriminated more features than older adults on all conditions. In both age groups, contextual feature discrimination accuracy decreased as the number of features increased. Moreover, older adults demonstrated near floor performance when tested with two or more binary features. We conclude that increasing context complexity strains attentional resources.

Low intensity magnetic field influences short-term memory: A study in a group of healthy students.

PubMed

Navarro, Enrique A; Gomez-Perretta, Claudio; Montes, Francisco

2016-01-01

This study analyzes if an external magnetic stimulus (2 kHz and approximately 0.1 μT applied near frontal cortex) influences working memory, perception, binary decision, motor execution, and sustained attention in humans. A magnetic stimulus and a sham stimulus were applied to both sides of the head (frontal cortex close to temporal-parietal area) in young and healthy male test subjects (n = 65) while performing Sternberg's memory scanning task. There was a significant change in reaction time. Times recorded for perception, sustained attention, and motor execution were lower in exposed subjects (P < 0.01). However, time employed in binary decision increased for subjects exposed to magnetic fields. From results, it seems that a low intensity 2 kHz exposure modifies short-term working memory, as well as perception, binary decision, motor execution, and sustained attention. © 2015 Wiley Periodicals, Inc.

Low Striatal Dopamine D2-type Receptor Availability is Linked to Simulated Drug Choice in Methamphetamine Users.

PubMed

Moeller, Scott J; Okita, Kyoji; Robertson, Chelsea L; Ballard, Michael E; Konova, Anna B; Goldstein, Rita Z; Mandelkern, Mark A; London, Edythe D

2018-03-01

Individuals with drug use disorders seek drugs over other rewarding activities, and exhibit neurochemical deficits related to dopamine, which is involved in value-based learning and decision-making. Thus, a dopaminergic disturbance may underpin drug-biased choice in addiction. Classical drug-choice assessments, which offer drug-consumption opportunities, are inappropriate for addicted individuals seeking treatment or abstaining. Fifteen recently abstinent methamphetamine users and 15 healthy controls completed two laboratory paradigms of 'simulated' drug choice (choice for drug-related vs affectively pleasant, unpleasant, and neutral images), and underwent positron emission tomography measurements of dopamine D2-type receptor availability, indicated by binding potential (BP ND ) for [ 18 F]fallypride. Thirteen of the methamphetamine users and 10 controls also underwent [ 11 C]NNC112 PET scans to measure dopamine D1-type receptor availability. Group analyses showed that, compared with controls, methamphetamine users chose to view more methamphetamine-related images on one task, with a similar trend on the second task. Regression analyses showed that, on both tasks, the more methamphetamine users chose to view methamphetamine images, specifically vs pleasant images (the most frequently chosen images across all participants), the lower was their D2-type BP ND in the lateral orbitofrontal cortex, an important region in value-based choice. No associations were observed with D2-type BP ND in striatal regions, or with D1-type BP ND in any region. These results identify a neurochemical correlate for a laboratory drug-seeking paradigm that can be administered to treatment-seeking and abstaining drug-addicted individuals. More broadly, these results refine the central hypothesis that dopamine-system deficits contribute to drug-biased decision-making in addiction, here showing a role for the orbitofrontal cortex.

Human transinformation rates during one-to-four axis tracking with a concurrent audio task

NASA Technical Reports Server (NTRS)

Baty, D. L.

1972-01-01

The information processing rates of six subjects performing one-, two-, three-, and four-axis compensatory tracking tasks, with and without a concurrent four-choice auditory task were determined. The purpose was to obtain further evidence concerning the nature of an hypothesized ceiling on human transinformation rates. Interference was found among tasks, but the evidence concerning a ceiling on information processing rates was inconclusive.

What top-down task sets do for us: an ERP study on the benefits of advance preparation in visual search.

PubMed

Eimer, Martin; Kiss, Monika; Nicholas, Susan

2011-12-01

When target-defining features are specified in advance, attentional target selection in visual search is controlled by preparatory top-down task sets. We used ERP measures to study voluntary target selection in the absence of such feature-specific task sets, and to compare it to selection that is guided by advance knowledge about target features. Visual search arrays contained two different color singleton digits, and participants had to select one of these as target and report its parity. Target color was either known in advance (fixed color task) or had to be selected anew on each trial (free color-choice task). ERP correlates of spatially selective attentional target selection (N2pc) and working memory processing (SPCN) demonstrated rapid target selection and efficient exclusion of color singleton distractors from focal attention and working memory in the fixed color task. In the free color-choice task, spatially selective processing also emerged rapidly, but selection efficiency was reduced, with nontarget singleton digits capturing attention and gaining access to working memory. Results demonstrate the benefits of top-down task sets: Feature-specific advance preparation accelerates target selection, rapidly resolves attentional competition, and prevents irrelevant events from attracting attention and entering working memory.

Perirhinal Cortex Resolves Feature Ambiguity in Configural Object Recognition and Perceptual Oddity Tasks

ERIC Educational Resources Information Center

Bartko, Susan J.; Winters, Boyer D.; Cowell, Rosemary A.; Saksida, Lisa M.; Bussey, Timothy J.

2007-01-01

The perirhinal cortex (PRh) has a well-established role in object recognition memory. More recent studies suggest that PRh is also important for two-choice visual discrimination tasks. Specifically, it has been suggested that PRh contains conjunctive representations that help resolve feature ambiguity, which occurs when a task cannot easily be…

Neural Correlates of Decision Making on a Gambling Task

ERIC Educational Resources Information Center

Carlson, Stephanie M.; Zayas, Vivian; Guthormsen, Amy

2009-01-01

Individual differences in affective decision making were examined by recording event-related potentials (ERPs) while 74 typically developing 8-year-olds (38 boys, 36 girls) completed a 4-choice gambling task (Hungry Donkey Task; E. A. Crone & M. W. van der Molen, 2004). ERP results indicated: (a) a robust P300 component in response to feedback…

Tool Choice for E-Learning: Task-Technology Fit through Media Synchronicity

ERIC Educational Resources Information Center

Sun, Jun; Wang, Ying

2014-01-01

One major challenge in online education is how to select appropriate e-learning tools for different learning tasks. Based on the premise of Task-Technology Fit Theory, this study suggests that the effectiveness of student learning in online courses depends on the alignment between two. Furthermore, it conceptualizes the formation of such a fit…

A Job with a Future? Delay Discounting, Magnitude Effects, and Domain Independence of Utility for Career Decisions.

ERIC Educational Resources Information Center

Schoenfelder, Thomas E.; Hantula, Donald A.

2003-01-01

Seniors (n=20) assessed two job offers with differences in domain (salary/tasks), delay (career-long earnings), and magnitude (initial salary offer). Contrary to discounted utility theory, choices reflected nonconstant discount rates for future salary/tasks (delay effect), lower discount rates for salary/preferred tasks (magnitude effect), and a…

Scaffolding Advice on Task Selection: A Safe Path toward Self-Directed Learning in On-Demand Education

ERIC Educational Resources Information Center

Kicken, Wendy; Brand-Gruwel, Saskia; van Merrienboer, Jeroen J. G.

2008-01-01

An intuitively appealing approach to increasing the flexibility of vocational education and training is to delegate choices on instruction, such as the selection of learning tasks, to students. However, empirical evidence shows that students often do not have sufficiently developed self-directed learning skills to select suitable tasks. This…

Counterintuitive and Alternative Moves Choice in the Water Jug Task

ERIC Educational Resources Information Center

Carder, Hassina P.; Handley, Simon J.; Perfect, Timothy J.

2008-01-01

MOVE problems, like the Tower of London (TOL) or the Water Jug (WJ) task, are planning tasks that appear structurally similar and are assumed to involve similar cognitive processes. Carder et al. [Carder, H.P., Handley, S.J., & Perfect, T.J. ( 2004). Deconstructing the Tower of London: Alternative moves and conflict resolution as predictors of…

Bottom-Up Influences on Voluntary Task Switching: The Elusive Homunculus Escapes

ERIC Educational Resources Information Center

Yeung, Nick

2010-01-01

Voluntary action can be studied by giving participants free choice over which task to perform in response to each presented stimulus. In such experiments, performance costs are observed when participants choose to switch tasks from the previous trial. It has been proposed that these costs primarily index the time-consuming operation of top-down…

The Effects of a Concurrent Task on Human Optimization and Self Control

ERIC Educational Resources Information Center

Reed, Phil; Thompson, Caitlin; Osborne, Lisa A.; McHugh, Louise

2011-01-01

Memory deficits have been shown to hamper decision making in a number of populations. In two experiments, participants were required to select one of three alternatives that varied in reinforcer amount and delay, and the effect of a concurrent task on a behavioral choice task that involved making either an impulsive, self-controlled, or optimal…

Choice Impulsivity: Definitions, Measurement Issues, and Clinical Implications

PubMed Central

Hamilton, Kristen R.; Mitchell, Marci R.; Wing, Victoria C.; Balodis, Iris M.; Bickel, Warren K.; Fillmore, Mark; Lane, Scott D.; Lejuez, C. W.; Littlefield, Andrew K.; Luijten, Maartje; Mathias, Charles W.; Mitchell, Suzanne H.; Napier, T. Celeste; Reynolds, Brady; Schütz, Christian G.; Setlow, Barry; Sher, Kenneth J.; Swann, Alan C.; Tedford, Stephanie E.; White, Melanie J.; Winstanley, Catharine A.; Yi, Richard; Potenza, Marc N.; Moeller, F. Gerard

2015-01-01

Background Impulsivity critically relates to many psychiatric disorders. Given the multi-faceted construct that impulsivity represents, defining core aspects of impulsivity is vital for the assessment and understanding of clinical conditions. Choice impulsivity (CI), involving the preferential selection of smaller sooner rewards over larger later rewards, represents one important type of impulsivity. Method The International Society for Research on Impulsivity (InSRI) convened to discuss the definition and assessment of CI and provide recommendations regarding measurement across species. Results Commonly used preclinical and clinical CI behavioral tasks are described, and considerations for each task are provided to guide CI task selection. Differences in assessment of CI (self-report, behavioral) and calculating CI indices (e.g., area-under-the-curve, indifference point, steepness of discounting curve) are discussed along with properties of specific behavioral tasks used in preclinical and clinical settings. Conclusions The InSRI group recommends inclusion of measures of CI in human studies examining impulsivity. Animal studies examining impulsivity should also include assessments of CI and these measures should be harmonized in accordance with human studies of the disorders being modeled in the preclinical investigations. The choice of specific CI measures to be included should be based on the goals of the study and existing preclinical and clinical literature using established CI measures. PMID:25867841

Prestimulus influences on auditory perception from sensory representations and decision processes.

PubMed

Kayser, Stephanie J; McNair, Steven W; Kayser, Christoph

2016-04-26

The qualities of perception depend not only on the sensory inputs but also on the brain state before stimulus presentation. Although the collective evidence from neuroimaging studies for a relation between prestimulus state and perception is strong, the interpretation in the context of sensory computations or decision processes has remained difficult. In the auditory system, for example, previous studies have reported a wide range of effects in terms of the perceptually relevant frequency bands and state parameters (phase/power). To dissociate influences of state on earlier sensory representations and higher-level decision processes, we collected behavioral and EEG data in human participants performing two auditory discrimination tasks relying on distinct acoustic features. Using single-trial decoding, we quantified the relation between prestimulus activity, relevant sensory evidence, and choice in different task-relevant EEG components. Within auditory networks, we found that phase had no direct influence on choice, whereas power in task-specific frequency bands affected the encoding of sensory evidence. Within later-activated frontoparietal regions, theta and alpha phase had a direct influence on choice, without involving sensory evidence. These results delineate two consistent mechanisms by which prestimulus activity shapes perception. However, the timescales of the relevant neural activity depend on the specific brain regions engaged by the respective task.

Multitasking as a choice: a perspective.

PubMed

Broeker, Laura; Liepelt, Roman; Poljac, Edita; Künzell, Stefan; Ewolds, Harald; de Oliveira, Rita F; Raab, Markus

2018-01-01

Performance decrements in multitasking have been explained by limitations in cognitive capacity, either modelled as static structural bottlenecks or as the scarcity of overall cognitive resources that prevent humans, or at least restrict them, from processing two tasks at the same time. However, recent research has shown that individual differences, flexible resource allocation, and prioritization of tasks cannot be fully explained by these accounts. We argue that understanding human multitasking as a choice and examining multitasking performance from the perspective of judgment and decision-making (JDM), may complement current dual-task theories. We outline two prominent theories from the area of JDM, namely Simple Heuristics and the Decision Field Theory, and adapt these theories to multitasking research. Here, we explain how computational modelling techniques and decision-making parameters used in JDM may provide a benefit to understanding multitasking costs and argue that these techniques and parameters have the potential to predict multitasking behavior in general, and also individual differences in behavior. Finally, we present the one-reason choice metaphor to explain a flexible use of limited capacity as well as changes in serial and parallel task processing. Based on this newly combined approach, we outline a concrete interdisciplinary future research program that we think will help to further develop multitasking research.

Prestimulus influences on auditory perception from sensory representations and decision processes

PubMed Central

McNair, Steven W.

2016-01-01

The qualities of perception depend not only on the sensory inputs but also on the brain state before stimulus presentation. Although the collective evidence from neuroimaging studies for a relation between prestimulus state and perception is strong, the interpretation in the context of sensory computations or decision processes has remained difficult. In the auditory system, for example, previous studies have reported a wide range of effects in terms of the perceptually relevant frequency bands and state parameters (phase/power). To dissociate influences of state on earlier sensory representations and higher-level decision processes, we collected behavioral and EEG data in human participants performing two auditory discrimination tasks relying on distinct acoustic features. Using single-trial decoding, we quantified the relation between prestimulus activity, relevant sensory evidence, and choice in different task-relevant EEG components. Within auditory networks, we found that phase had no direct influence on choice, whereas power in task-specific frequency bands affected the encoding of sensory evidence. Within later-activated frontoparietal regions, theta and alpha phase had a direct influence on choice, without involving sensory evidence. These results delineate two consistent mechanisms by which prestimulus activity shapes perception. However, the timescales of the relevant neural activity depend on the specific brain regions engaged by the respective task. PMID:27071110

A Frontal Dopamine System for Reflective Exploratory Behavior

PubMed Central

Blanco, Nathaniel J.; Love, Bradley C.; Cooper, Jessica A.; McGeary, John E.; Knopik, Valerie S.; Maddox, W. Todd

2015-01-01

The COMT gene modulates dopamine levels in prefrontal cortex with Met allele carriers having lower COMT enzyme activity and, therefore, higher dopamine levels compared to Val/Val homozygotes. Concordantly, Val/Val homozygotes tend to perform worse and display increased (interpreted as inefficient) frontal activation in certain cognitive tasks. In a sample of 209 participants, we test the hypothesis that Met carriers will be advantaged in a decision-making task that demands sequencing exploratory and exploitive choices to minimize uncertainty about the reward structure in the environment. Previous work suggests that optimal performance depends on limited cognitive resources supported by prefrontal systems. If so, Met carriers should outperform Val/Val homozygotes, particularly under dual-task conditions that tax limited cognitive resources. In accord with these a priori predictions, Met carriers were more resilient in the face of cognitive load, continuing to explore in a sophisticated manner. We fit computational models that embody sophisticated reflective and simple reflexive strategies to further evaluate participants' exploration behavior. The Ideal Actor model reflectively updates beliefs and plans ahead, taking into account the information gained by each choice and making choices that maximize long-term payoffs. In contrast, the Naïve Reinforcement Learning (RL) model instantiates the reflexive account of choice, in which the values of actions are based only on the rewards experienced so far. Its beliefs are updated reflexively in response to observed changes in rewards. Converging with standard analyses, Met carriers were best characterized by the Ideal Actor model, whereas Val/Val homozygotes were best characterized by the Naive RL model, particularly under dual-task conditions. PMID:26004676

Development of using experimenter-given cues in infant chimpanzees: longitudinal changes in behavior and cognitive development.

PubMed

Okamoto-Barth, Sanae; Tomonaga, Masaki; Tanaka, Masayuki; Matsuzawa, Tetsuro

2008-01-01

The use of gaze shifts as social cues has various evolutionary advantages. To investigate the developmental processes of this ability, we conducted an object-choice task by using longitudinal methods with infant chimpanzees tested from 8 months old until 3 years old. The experimenter used one of six gestures towards a cup concealing food; tapping, touching, whole-hand pointing, gazing plus close-pointing, distant-pointing, close-gazing, and distant-gazing. Unlike any other previous study, we analyzed the behavioral changes that occurred before and after choosing the cup. We assumed that pre-choice behavior indicates the development of an attentional and spatial connection between a pointing cue and an object (e.g. Woodward, 2005); and post-choice behavior indicates the emergence of object permanence (e.g. Piaget, 1954). Our study demonstrated that infant chimpanzees begin to use experimenter-given cues with age (after 11 months of age). Moreover, the results from the behavioral analysis showed that the infants gradually developed the spatial link between the pointing as an object-directed action and the object. Moreover, when they were 11 months old, the infants began to inspect the inside of the cup, suggesting the onset of object permanence. Overall, our results imply that the ability to use the cues is developing and mutually related with other cognitive developments. The present study also suggests what the standard object-choice task actually measures by breaking the task down into the developmental trajectories of its component parts, and describes for the first time the social-physical cognitive development during the task with a longitudinal method.

The role of the striatum in effort-based decision-making in the absence of reward.

PubMed

Schouppe, Nathalie; Demanet, Jelle; Boehler, Carsten N; Ridderinkhof, K Richard; Notebaert, Wim

2014-02-05

Decision-making involves weighing costs against benefits, for instance, in terms of the effort it takes to obtain a reward of a given magnitude. This evaluation process has been linked to the dorsal anterior cingulate cortex (dACC) and the striatum, with activation in these brain structures reflecting the discounting effect of effort on reward. Here, we investigate how cognitive effort influences neural choice processes in the absence of an extrinsic reward. Using functional magnetic resonance imaging in humans, we used an effort-based decision-making task in which participants were required to choose between two options for a subsequent flanker task that differed in the amount of cognitive effort. Cognitive effort was manipulated by varying the proportion of incongruent trials associated with each choice option. Choice-locked activation in the striatum was higher when participants chose voluntarily for the more effortful alternative but displayed the opposite trend on forced-choice trials. The dACC revealed a similar, yet only trend-level significant, activation pattern. Our results imply that activation levels in the striatum reflect a cost-benefit analysis, in which a balance is made between effort discounting and the intrinsic motivation to choose a cognitively challenging task. Moreover, our findings indicate that it matters whether this challenge is voluntarily chosen or externally imposed. As such, the present findings contrast with classical findings on effort discounting that found reductions in striatum activation for higher effort by finding enhancements of the same neural circuits when a cognitively challenging task is voluntarily selected and does not entail the danger of losing reward.

Comparison of rate one-half, equivalent constraint length 24, binary convolutional codes for use with sequential decoding on the deep-space channel

NASA Technical Reports Server (NTRS)

Massey, J. L.

1976-01-01

Virtually all previously-suggested rate 1/2 binary convolutional codes with KE = 24 are compared. Their distance properties are given; and their performance, both in computation and in error probability, with sequential decoding on the deep-space channel is determined by simulation. Recommendations are made both for the choice of a specific KE = 24 code as well as for codes to be included in future coding standards for the deep-space channel. A new result given in this report is a method for determining the statistical significance of error probability data when the error probability is so small that it is not feasible to perform enough decoding simulations to obtain more than a very small number of decoding errors.

Behavioral laterality of the brain: support for the binary construct of hemisity

PubMed Central

Morton, Bruce E.

2013-01-01

Three terms define brain behavioral laterality: hemispheric dominance identifies the cerebral hemisphere producing one's first language. Hemispheric asymmetry locates the brain side of non-language skills. A third term is needed to describe a person's binary thinking, learning, and behaving styles. Since the 1950s split-brain studies, evidence has accumulated that individuals with right or left brain behavioral orientations (RPs or LPs) exist. Originally, hemisphericity sought, but failed, to confirm the existence of such individual differences, due to its assertion that each individual lay somewhere on a gradient between competing left and right brain extremes. Recently, hemisity, a more accurate behavioral laterality context, has emerged. It posits that one's behavioral laterality is binary: i.e., inherently either right or left brain-oriented. This insight enabled the quantitative determination of right or left behavioral laterality of thousands of subjects. MRI scans of right and left brain-oriented groups revealed two neuroanatomical differences. The first was an asymmetry of an executive element in the anterior cingulate cortex (ACC). This provided hemisity both a rationale and a primary standard. RPs and LPs gave opposite answers to many behavioral preference “either-or,” forced choice questions. This showed that several sex vs. hemisity traits are being conflated by society. Such was supported by the second neuroanatomical difference between the hemisity subtypes, that RPs of either sex had up to three times larger corpus callosi than LPs. Individuals of the same hemisity but opposite sex had more personality traits in common than those of the same sex but different hemisity. Although hemisity subtypes were equally represented in the general population, the process of higher education and career choice caused substantial hemisity sorting among the professions. Hemisity appears to be a valid and promising area for quantitative research of behavioral laterality. PMID:24101910

Behavioral laterality of the brain: support for the binary construct of hemisity.

PubMed

Morton, Bruce E

2013-10-01

hemispheric dominance identifies the cerebral hemisphere producing one's first language. Hemispheric asymmetry locates the brain side of non-language skills. A third term is needed to describe a person's binary thinking, learning, and behaving styles. Since the 1950s split-brain studies, evidence has accumulated that individuals with right or left brain behavioral orientations (RPs or LPs) exist. Originally, hemisphericity sought, but failed, to confirm the existence of such individual differences, due to its assertion that each individual lay somewhere on a gradient between competing left and right brain extremes. Recently, hemisity, a more accurate behavioral laterality context, has emerged. It posits that one's behavioral laterality is binary: i.e., inherently either right or left brain-oriented. This insight enabled the quantitative determination of right or left behavioral laterality of thousands of subjects. MRI scans of right and left brain-oriented groups revealed two neuroanatomical differences. The first was an asymmetry of an executive element in the anterior cingulate cortex (ACC). This provided hemisity both a rationale and a primary standard. RPs and LPs gave opposite answers to many behavioral preference "either-or," forced choice questions. This showed that several sex vs. hemisity traits are being conflated by society. Such was supported by the second neuroanatomical difference between the hemisity subtypes, that RPs of either sex had up to three times larger corpus callosi than LPs. Individuals of the same hemisity but opposite sex had more personality traits in common than those of the same sex but different hemisity. Although hemisity subtypes were equally represented in the general population, the process of higher education and career choice caused substantial hemisity sorting among the professions. Hemisity appears to be a valid and promising area for quantitative research of behavioral laterality.

The Relationship between Observed Task Characteristics and the Pattern of Seventh Grade Students' Situational Engagement during a Science Unit

NASA Astrophysics Data System (ADS)

Glassman, Sarah J.

Student engagement is an important aspect of teaching and learning. Traditionally, engagement has been measured as a static trait. This study measured engagement as a fluid trait in order to explore the relationship between seventh grade students' situational engagement over a science unit and five specific task characteristics. Further, this study investigated how the changing pattern of instruction is related to a changing pattern of student engagement. Informed by Self-Determination Theory, the five specific task characteristics investigated were: the use of tasks that give students opportunities to act autonomously (choice), the use of tasks that challenge students (challenge), constructive feedback from the teacher or peers that guides students work on the current task (feedback), the inclusion of tasks that require student collaboration (collaboration), and tasks in which the importance or relevance is explained to students or the task includes a real-world problem or scenario (real-life significance). Student engagement was measured as a multidimensional trait consisting of behavioral, emotional, and cognitive dimensions. Participants included two teachers and 37 students. Two classrooms were observed and video-recorded for 10 consecutive 1.5 hour blocks during a unit investigating cells. At the end of each block students completed a three item survey for each task. For all tasks in both classrooms, the cumulative presence of task characteristics correlated with student engagement. However, students' behavioral engagement negatively correlated with the use of choice. Students' engagement increased from low to high during four related tasks exhibiting the highest cumulative presence of task characteristics. Nine out of 10 tasks with the highest student engagement involved hands-on learning. However, students' engagement was lower during tasks elaborating on those hands-on tasks.

Distinct roles of visual, parietal, and frontal motor cortices in memory-guided sensorimotor decisions.

PubMed

Goard, Michael J; Pho, Gerald N; Woodson, Jonathan; Sur, Mriganka

2016-08-04

Mapping specific sensory features to future motor actions is a crucial capability of mammalian nervous systems. We investigated the role of visual (V1), posterior parietal (PPC), and frontal motor (fMC) cortices for sensorimotor mapping in mice during performance of a memory-guided visual discrimination task. Large-scale calcium imaging revealed that V1, PPC, and fMC neurons exhibited heterogeneous responses spanning all task epochs (stimulus, delay, response). Population analyses demonstrated unique encoding of stimulus identity and behavioral choice information across regions, with V1 encoding stimulus, fMC encoding choice even early in the trial, and PPC multiplexing the two variables. Optogenetic inhibition during behavior revealed that all regions were necessary during the stimulus epoch, but only fMC was required during the delay and response epochs. Stimulus identity can thus be rapidly transformed into behavioral choice, requiring V1, PPC, and fMC during the transformation period, but only fMC for maintaining the choice in memory prior to execution.

Cognitive Modeling of Individual Variation in Reference Production and Comprehension

PubMed Central

Hendriks, Petra

2016-01-01

A challenge for most theoretical and computational accounts of linguistic reference is the observation that language users vary considerably in their referential choices. Part of the variation observed among and within language users and across tasks may be explained from variation in the cognitive resources available to speakers and listeners. This paper presents a computational model of reference production and comprehension developed within the cognitive architecture ACT-R. Through simulations with this ACT-R model, it is investigated how cognitive constraints interact with linguistic constraints and features of the linguistic discourse in speakers’ production and listeners’ comprehension of referring expressions in specific tasks, and how this interaction may give rise to variation in referential choice. The ACT-R model of reference explains and predicts variation among language users in their referential choices as a result of individual and task-related differences in processing speed and working memory capacity. Because of limitations in their cognitive capacities, speakers sometimes underspecify or overspecify their referring expressions, and listeners sometimes choose incorrect referents or are overly liberal in their interpretation of referring expressions. PMID:27092101

Food labels promote healthy choices by a decision bias in the amygdala.

PubMed

Grabenhorst, Fabian; Schulte, Frank P; Maderwald, Stefan; Brand, Matthias

2013-07-01

Food labeling is the major health policy strategy to counter rising obesity rates. Based on traditional economic theory, such strategies assume that detailed nutritional information will necessarily help individuals make better, healthier choices. However, in contrast to the well-known utility of labels in food marketing, evidence for the efficacy of nutritional labeling is mixed. Psychological and behavioral economic theories suggest that successful marketing strategies activate automatic decision biases and emotions, which involve implicit emotional brain systems. Accordingly, simple, intuitive food labels that engage these neural systems could represent a promising approach for promoting healthier choices. Here we used functional MRI to investigate this possibility. Healthy, mildly hungry subjects performed a food evaluation task and a food choice task. The main experimental manipulation was to pair identical foods with simple labels that emphasized either taste benefits or health-related food properties. We found that such labels biased food evaluations in the amygdala, a core emotional brain system. When labels biased the amygdala's evaluations towards health-related food properties, the strength of this bias predicted behavioral shifts towards healthier choices. At the time of decision-making, amygdala activity encoded key decision variables, potentially reflecting active amygdala participation in food choice. Our findings underscore the potential utility of food labeling in health policy and indicate a principal role for emotional brain systems when labels guide food choices. Copyright © 2013 Elsevier Inc. All rights reserved.