Neural correlates of stimulus response and stimulus outcome shifting in healthy participants and MS patients

Introduction

Adaptation to changing situations can be mediated by two strategies: (1) Evaluation of a response and (2) Evaluation of outcome values in relation to objects. Previous studies indicate that response shifting is associated with a network comprising the left frontal cortex and parietal cortex connected by the superior longitudinal fascicle, whereas outcome evaluation is associated with a network consisting of the orbitofrontal cortex, amygdala and uncinate fascicle. However, these studies rarely compared both kinds of adaptation directly and existing fMRI studies with healthy subjects are not informative about the role of the two fiber systems.

Methods

We analyzed stimulus response shifting and stimulus outcome shifting in two studies, one fMRI-study on healthy participants and one study on patients with MS involving structural MRI (Diffusion Tensor Imaging, Voxel Based Morphometry, Ventricular volumetry). Two tasks were used, identical in presentation but different in instruction, controlling for effects of lower level processing. In the SRS task, participants had to perform a “Go” or “NoGo” response depending on a stimulus change: if the stimulus remained the same, they had to continue with the former type of response, if it changed they had to adapt their response pattern. In the SOS task they had to perform a “Go” response only if the presented stimulus corresponded to that of an internal alternating series.

Results

fMRI findings showed that SRS is related to a bilateral parietal-premotor network. In the left hemisphere the prefrontal cortex was also involved. SOS was lateralized to the right hemisphere, particularly to the anterior temporal pole and amygdala, and the inferior parietal cortex. MS patients impaired on this task suffered from lesions in the right uncinate fascicle and showed an enlarged right frontal lateral ventricle.

Conclusion

With physically identical tasks, a functional neuronal segregation can be demonstrated for stimulus response shifting (bilateral activations with a focus in the left prefrontal cortex) and stimulus outcome shifting (right anterior temporal lobe and right supramarginal gyrus).     

Sales Technology Applications: Interactive Video Technology in Sales Training: A Case Study

Interactive video (IV), a new technology for training, has had a recent surge in popularity. The use of interactive video technology has been reported to reduce training costs, increase quality, and decrease the amount of time required for training. The major characteristics of this new technology are presented. A state-of-the-art application of an IV system for sales training developed at BellSouth Services is discussed. The results confirm that IV is a promising new sales training tool.     

An anxiety-induced bias in the perception of a bistable point-light walker

Human sensitivity for social cues is exquisite, as illustrated by the ease with which simplified point-light movements invoke social and emotional responses. Compared to faces, these biological motion stimuli only recently started to be used to explore questions regarding social cognition and anxiety. We presented human point-light walkers that could be perceived as facing towards or facing away from the observer, and tested whether participants with high social anxiety would perceive these bistable stimuli differently, because this type of stimuli has particular relevance for them. The results showed that observers with high social anxiety tended to see walkers as facing away more frequently than those with low social anxiety. This may mean that high socially anxious observers are biased towards the more positive perceptual alternative because they are motivated to protect themselves against threatening social experiences, but we also explore alternative explanations. The findings are in line with the evidence for a positivity bias in perception, also called wishful seeing, but in contrast with the attentional negativity bias often found in social anxiety. We discuss reasons for this divergence and possible limitations of the current study.     

A slow component of classic Stroop interference

The interference in colour naming may extend beyond critical Stroop trials. This “slow” effect was first discovered in emotional Stroop tasks, but is extended here to classical Stroop. In two experiments, meaningless coloured letter strings followed a colour word or neutral word. Student participants (Experiment 1), and 18 stroke patients and 18 matched controls (Experiment 2) showed substantial interference by incongruent colour words, both in the word trial (fast component) and in the subsequent string trial (slow component). Different patient subgroups emerged from the comparison of Stroop performance with the controls. An association of fast and slow components was only found in one subgroup. Exploratory analyses revealed no clear differences in damage location between subgroups. Fast interference caused by colour-meaning conflict may be specific for classical Stroop, but the broader occurrence of slow effects suggests a more generalised process of disengagement from attention-demanding stimuli.     

Evolutionary Psychology of Facial Attractiveness

The human face communicates an impressive number of visual signals. Although adults' ratings of facial attractiveness are consistent across studies, even cross-culturally, there has been considerable controversy surrounding attempts to identify the facial features that cause faces to be judged attractive or unattractive. Studies of physical attractiveness have attempted to identify the features that contribute to attractiveness by studying the relationships between attractiveness and (a) symmetry, (b) averageness, and (c) nonaverage sexually dimorphic features (hormone markers). Evolutionary psychology proposes that these characteristics all pertain to health, suggesting that humans have evolved to view certain features as attractive because they were displayed by healthy individuals. However, the question remains how single features that are considered attractive relate to each other, and if they form a single ornament that signals mate quality. Moreover, some researchers have recently explained attractiveness preferences in terms of individual differences that are predictable. This article briefly describes what is currently known from attractiveness research, reviews some recent advances, and suggests areas for future researchers' attention.     

Causation as Simultaneous and Continuous

We propose that all actual causes are simultaneous with their direct effects, as illustrated by both everyday examples and the laws of physics. We contrast this view with the sequential conception of causation, according to which causes must occur prior to their effects. The key difference between the two views of causation lies in differing assumptions about the mathematical structure of time.     

How Ethical is Islamic Banking in the Light of the Objectives of Islamic Law?

Islamic banking is based on moral foundations that make it distinct from conventional banking. Some argue that because of its foundation in Islam, Islamic banking may represent a more morally appealing alternative. Yet, evidence shows that this is not the case. Indeed, the current practice of Islamic banking has not been able to achieve its goals which are based on Islam's moral values: to enhance justice, equitability, and social well‐being. This essay examines the extent to which Islamic banking is ethical and concludes that the practice of the industry does not seem to be de facto ethical from the Islamic perspective of ethical values. It only consists in trading the same instruments of conventional banks without genuinely enforcing Islam's ethical vision. The practice of Islamic banking misrepresents Islam and does not contribute to solving social problems. The interaction between maqasid al‐shari?a (objectives of Islamic law) and qiyās (deductive analogy) provides a supplementary tool for interpreting the failure of the prior in terms of the practical misuse of the latter by Islamic banks. This essay provides an interpretive approach to the current debate about why Islamic banking has failed and suggests ways to move cautiously in the future.