Biasing the perception of ambiguous vocal affect: a TMS study on frontal asymmetry

Several sources of evidence point toward a link between asymmetry of prefrontal brain activity and approach–withdrawal tendencies. Here, we tested the causal nature of this link and examined if the categorization of an ambiguous approach- or withdrawal-related vocal signal can be biased by manipulating left and right frontal neural activity. We used voice morphing of affective non-verbal vocalizations to create individually tailored affectively ambiguous stimuli on an Anger–Fear continuum—two emotions that represent extremes on the approach–withdrawal dimension. We tested perception of these stimuli after 10 min of low-frequency repetitive transcranial magnetic stimulation over left or right dorsolateral prefrontal cortex or over the vertex (control), a technique that has transient inhibitory effects on the targeted brain region. As expected, ambiguous stimuli were more likely perceived as expressing Anger (approach) than Fear (withdrawal) after right prefrontal compared with left prefrontal or control stimulation. These results provide the first evidence that the manipulation of asymmetrical activity in prefrontal cortex can change the explicit categorization of ambiguous emotional signals

Electrocortical components of anticipation and consumption in a monetary incentive delay task

In order to improve our understanding of the components that reflect functionally important processes during reward anticipation and consumption, we used principle components analyses (PCA) to separate and quantify averaged ERP data obtained from each stage of a modified monetary incentive delay (MID) task. Although a small number of recent ERP studies have reported that reward and loss cues potentiate ERPs during anticipation, action preparation, and consummatory stages of reward processing, these findings are inconsistent due to temporal and spatial overlap between the relevant electrophysiological components. Our results show three components following cue presentation are sensitive to incentive cues (N1, P3a, P3b). In contrast to previous research, reward‐related enhancement occurred only in the P3b, with earlier components more sensitive to break‐even and loss cues. During feedback anticipation, we observed a lateralized centroparietal negativity that was sensitive to response hand but not cue type. We also show that use of PCA on ERPs reflecting reward consumption successfully separates the reward positivity from the independently modulated feedback‐P3. Last, we observe for the first time a new reward consumption component: a late negativity distributed over the left frontal pole. This component appears to be sensitive to response hand, especially in the context of monetary gain. These results illustrate that the time course and sensitivities of electrophysiological activity that follows incentive cues do not follow a simple heuristic in which reward incentive cues produce enhanced activity at all stages and substages

Neural correlates of cognitive dissonance and choice-induced preference change

According to many modern economic theories, actions simply reflect an individual's preferences, whereas a psychological phenomenon called “cognitive dissonance” claims that actions can also create preference. Cognitive dissonance theory states that after making a difficult choice between two equally preferred items, the act of rejecting a favorite item induces an uncomfortable feeling (cognitive dissonance), which in turn motivates individuals to change their preferences to match their prior decision (i.e., reducing preference for rejected items). Recently, however, Chen and Risen [Chen K, Risen J (2010) J Pers Soc Psychol 99:573–594] pointed out a serious methodological problem, which casts a doubt on the very existence of this choice-induced preference change as studied over the past 50 y. Here, using a proper control condition and two measures of preferences (self-report and brain activity), we found that the mere act of making a choice can change self-report preference as well as its neural representation (i.e., striatum activity), thus providing strong evidence for choice-induced preference change. Furthermore, our data indicate that the anterior cingulate cortex and dorsolateral prefrontal cortex tracked the degree of cognitive dissonance on a trial-by-trial basis. Our findings provide important insights into the neural basis of how actions can alter an individual's preferences

A highly polarised radio jet during the 1998 outburst of the black hole transient XTE J1748-288

XTE J1748-288 is a black hole X-ray transient which went into outburst in 1998 June. The X-ray lightcurves showed canonical morphologies, with minor variations on the ``Fast Rise Exponential Decay'' profile. The radio source, however, reached an unusually high flux density of over 600 mJy. This high radio flux was accompanied by an exceptional (>20%) fractional linear polarisation, the variability of which was anti-correlated with the flux density. We use this variability to discuss possible depolarisation mechanisms and to predict the underlying behaviour of the (unresolved) core/jet components.Comment: Accepted for publication in MNRA

The selection of an appropriate count data model for modelling health insurance and health care demand: Case of Indonesia

This is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.We apply several estimators to Indonesian household data to estimate the relationship between health insurance and the number of outpatient visits to public and private providers. Once endogeneity of insurance is taken into account, there is a 63 percent increase in the average number of public visits by the beneficiaries of mandatory insurance for civil servants. Individuals' decisions to make first contact with private providers is affected by private insurance membership. However, insurance status does not make any difference for the number of future outpatient visits

On jealousy, envy, sex differences and temperament in humans and dogs

Cook, Prichard, Spivak, and Berns (2018) find that dogs’ levels of trait aggression are positively correlated with their amygdala activation when observing their caregivers giving a food to a fake dog. The authors conclude that this may provide neural evidence in dogs for the experience of jealousy, an emotion that some psychologists consider to be unique to humans. Here we explain the difference between the emotions of jealousy and envy, suggesting some ideas for future experiments that may help disentangle the experience of jealousy from that of envy in dogs. We also propose ideas for future research that may yield a more in-depth understanding of jealousy, and whether jealousy exists, in non-human animals

Individual differences in dissonance arousal/reduction relate to physical exercise : testing the action-based model

Introduction: The present research was designed to test predictions derived from the action-based model of cognitive dissonance theory. These predictions were that dissonance arousal would be negatively related to effective behavior, and that dissonance reduction would be positively related to effective behavior. Method: Dissonance arousal and reduction were measured using an individual differences questionnaire. Effective behavior was measured as amount of physical exercise obtained from an exercise app that measures exercise using GPS (cycling kilometers over one year; Study 1) and from self-reports (number of days during the previous week; Study 2–3). Results: Results suggested that individual differences in dissonance arousal relate to less exercise and that individual differences in dissonance reduction relate to more exercise. Statistically controlling for trait approach and avoidance motivation as well as satisfaction with life revealed that dissonance processes predicted exercise behavior over these traits. This pattern of results was generally consistent across the three studies. Moreover, results from Studies 2–3 suggested possible statistical mediators from the exercise commitment literature of the relationship between trait dissonance arousal/reduction and exercise behavior. Discussion and conclusion: These results highlight the importance of considering dissonance processes as adaptive ones, and they suggest possible ways of increasing exercise behavior

On jealousy, envy, sex differences and temperament in humans and dogs

Cook, Prichard, Spivak, and Berns (2018) find that dogs’ levels of trait aggression are positively correlated with their amygdala activation when observing their caregivers giving a food to a fake dog. The authors conclude that this may provide neural evidence in dogs for the experience of jealousy, an emotion that some psychologists consider to be unique to humans. Here we explain the difference between the emotions of jealousy and envy, suggesting some ideas for future experiments that may help disentangle the experience of jealousy from that of envy in dogs. We also propose ideas for future research that may yield a more in-depth understanding of jealousy, and whether jealousy exists, in non-human animals

Social power and approach-related neural activity

It has been argued that power activates a general tendency to approach whereas powerlessness activates a tendency to inhibit. The assumption is that elevated power involves reward-rich environments, freedom and, as a consequence, triggers an approach-related motivational orientation and attention to rewards. In contrast, reduced power is associated with increased threat, punishment and social constraint and thereby activates inhibition-related motivation. Moreover, approach motivation has been found to be associated with increased relative left-sided frontal brain activity, while withdrawal motivation has been associated with increased right sided activations. We measured EEG activity while subjects engaged in a task priming either high o

Optimisation of Grease Application to Railway Track

Trackside lubricators are designed to deliver grease to passing wheel flanges to reduce wheel and rail wear on curves. Ensuring that they are set up to deliver sufficient grease for the range of vehicles passing a site can be a challenge. For example, vehicle dynamics modelling and site investigations have shown that the wheels of passenger vehicles do not run as close to the rail face as those of freight vehicles, meaning that they are less likely to contact the grease and lubricate subsequent curves. To investigate the effects of different trackside devices, and the influence of parameters governing grease pickup, including lateral wheel displacement and pump durations, a bespoke test rig was built at the University of Sheffield. The rig used a scaled wheel, a short section of rail and a modern trackside lubricator set-up. Experiments involving different lateral wheel displacements and pumping durations were carried out, in addition to the visualisation of the size of the grease bulb. This showed how a grease bulb grows. It also indicated that a worn profile is likely to require greater wheel displacement to make contact with grease bulbs when compared to a new wheel profile. The experimental results showed that increasing pickup of grease can be expected when an additional component called a GreaseGuide™ was fitted to a regular grease delivery unit (GDU) on the rail. The efficiency of grease pickup was investigated, and test results exploring increasing pump durations have indicated a relationship between pickup and bulb size. To validate the use of the scaled rig, similar tests were carried out using a full-scale test rig. The full-scale results were compared to the experimental results of the scaled wheel rig. This showed that whilst there were differences between the two test rigs in absolute values and anomalous results, overall trends were the same on both test scales. The effect of temperature on bulb size and pumpability of grease was also investigated. This work can be extended further by using the same method to investigate other parameters that affect the lubrication of curves. This can lead to optimised lubricator set-up to ensure that the track is fully lubricated all the time