Temporal dynamics of anxiety-related attentional bias: is affective context a missing piece of the puzzle?

Previous research has demonstrated that anxious individuals attend to negative emotional information at the expense of other information. This is commonly referred to as attentional bias. The field has historically conceived of this process as relatively static; however, research by [Zvielli, A., Bernstein, A., &; Koster, E. H. W. (2014). Dynamics of attentional bias to threat in anxious adults: Bias towards and/or away? PLoS ONE, 9(8), e104025; Zvielli, A., Bernstein, A., &; Koster, E. H. W. (2015). Temporal dynamics of attentional bias. Clinical Psychological Science, 3(5), 772–788.], and others, challenges this assumption by demonstrating considerable temporal variability in attentional bias amongst anxious individuals. Still, the mechanisms driving these temporal dynamics are less well known. Using a modified dot-probe task, the present study examined the impact of two relevant contextual variables- affective valence and trial repetition. Affective context was instantiated by the presentation of negative versus neutral pictures before each trial, while repetition context was achieved via the presentation of the valenced pictures in either a blocked- or mixed-trial design. Results indicate that individuals with higher trait-anxiety levels were significantly more influenced by blocked presentations of negative affective information, leading to greater temporal fluctuations in attentional bias. Furthermore, our findings provide additional evidence that attentional bias is best conceptualised as dynamic and variable, and that an individual’s affective experience is one factor that regulates attentional bias dynamics. Implications relating to theoretical and methodological factors are discussed.     

Using finite mixture of GLMs to explore variability in children's flexibility in a task-switching paradigm

The present study illustrates the usefulness of finite mixture of generalized linear models (GLMs) to examine variability in cognitive strategies during childhood. More precisely, it addresses this variability in set-shifting situations where task-goal updating is endogenously driven. In a task-switching paradigm 5–6-year-olds had to switch between color- and shape-matching rules as a function of a predetermined, predictable task sequence. A finite mixture of GLMs was fitted to explore individual differences in performance. The statistical model revealed five response profiles, defined by accuracy and response times. These response profiles likely correspond to different cognitive strategies with varying efficiency and differential relations to working memory capacity (assessed by backward digit span). These results illustrate the heuristic value of statistical modeling to reveal the behavioral and cognitive variability in the temporal dynamics of children's cognitive functioning.     

The Role of Atomic Repertoires in Complex Behavior

Evolution and reinforcement shape adaptive forms and adaptive behavior through many cycles of blind variation and selection, and therein lie their parsimony and power. Human behavior is distinctive in that this shaping process is commonly "short circuited": Critical variations are induced in a single trial. The processes by which this economy is accomplished have a common feature: They all exploit one or more atomic repertoires, elementary units of behavior each under control of a distinctive stimulus. By appropriate arrangements of these discriminative stimuli, an indefinite number of permutations of atomic units can be evoked. When such a permutation satisfies a second contingency, it can come under control of the relevant context, and the explicit arrangement of discriminative stimuli will no longer be required. Consequently, innovations in adaptive behavior can spread rapidly through the population. A consideration of atomic repertoires informs our interpretation of generalized operants and other phenomena that are otherwise difficult to explain. Observational learning is discussed as a case in point.     

Quadriceps Torque,Peak Variability and Strength Endurance in Patients after Anterior Cruciate Ligament Reconstruction: Impact of Local Muscle Fatigue

Abstract

We tested if ACL-reconstructed participants show a decreased quadriceps torque, a lower muscle endurance capacity and a higher peak torque variability compared to unimpaired control participants prior to and following local muscle fatigue. Participants (n?=?19, 10 women; 25?±?5yrs.) with unilateral hamstrings autograft ACL-reconstruction and a matched unimpaired control group were recruited. Participants performed two maximal isometric voluntary force (MIVF) contractions of the knee extensors. In between, standardized local muscle fatigue was induced. ACL-reconstructed knees display a lower peak torque of the knee extensors in comparison to the contralateral limb (3.2?±?.3Nm/kg vs. 3.5?±?.3 Nm/kg). Peak torque variability and fatigue resistance were not affected by local muscle fatigue (p > .05). Participants with ACL-reconstructed knees show a persistent quadriceps muscle dysfunction. This dysfunction and lower limb side asymmetries might be risk factors for ACL re-ruptures.     

Corralling the Ingroup: Deviant Derogation and Perception of Group Variability

ABSTRACT

Two experiments investigated the relationship between the evaluation of a deviant group member and the perceived group variability among participants with varying degrees of ingroup identification. In Experiment 1 (N?=?79) ingroup identification was negatively associated with perceived ingroup variability following the presentation of a deviant ingroup member. This relationship was mediated by ratings of the deviant: the stronger the identification, the more negatively the deviant was evaluated, and the more homogeneous the ingroup was perceived. These effects were replicated in Experiment 2 (N?=?169), which also showed that there was no association between ingroup identification and the representation of the outgroup following exposure to a deviant outgroup member. The findings suggest that deviant derogation may serve to isolate undesirable members from the rest of the ingroup and protect the group's identity.     

Mood-congruent thoughts and personality disorder pathology

The primary aim of this research was to investigate associations that depression severity and trait anxiety have with reactions to specific, identifiable thoughts experienced by persons with varying levels of personality disorder (PD) pathology as they went about their day-to-day lives. Ninety-eight psychotropic medication-free persons participated in an experience sampling assessment procedure over four consecutive days, during which participants recorded specific thoughts experienced moments before a page signal was received and corresponding ratings of thought discomfort. Thought discomfort, regarded as an emotional reaction to thoughts or their evaluation, was moderately associated with several forms of PD pathology, particularly Cluster C pathology. Once depression severity and trait anxiety were controlled, however, associations between PD pathology and thought discomfort were eliminated. Findings from this research generally support the mood-congruence of negatively valenced thoughts in relation to PD pathology.     

RACE/A: an architectural account of the interactions between learning, task control, and retrieval dynamics

This article discusses how sequential sampling models can be integrated in a cognitive architecture. The new theory Retrieval by Accumulating Evidence in an Architecture (RACE/A) combines the level of detail typically provided by sequential sampling models with the level of task complexity typically provided by cognitive architectures. We will use RACE/A to model data from two variants of a picture-word interference task in a psychological refractory period design. These models will demonstrate how RACE/A enables interactions between sequential sampling and long-term declarative learning, and between sequential sampling and task control. In a traditional sequential sampling model, the onset of the process within the task is unclear, as is the number of sampling processes. RACE/A provides a theoretical basis for estimating the onset of sequential sampling processes during task execution and allows for easy modeling of multiple sequential sampling processes within a task.     

Increasing perceived variability reduces prejudice and discrimination

We examined whether increasing individuals' perceived variability of an out-group reduces prejudice and discrimination toward its members. In a series of 4 laboratory and field experiments, we attracted participants' attention to either the homogeneity or the heterogeneity of members of an out-group, and then measured their attitudes or behaviors. Perceived variability was manipulated by making subgroups salient, by portraying the out-group members as having diverse opinions, by making salient that out-group members have different characteristics, or by asking participants to think about differences among out-group members. Prejudice and discrimination were measured in terms of self-reported attitudes, distribution of rewards, helping an out-group confederate, and evaluation of an out-group candidate in a simulated hiring decision. In all experiments, perceived variability decreased prejudice and discrimination. This effect may be due to the fact that perceived variability decreases the role of group membership in the production of attitudes and behaviors toward other individuals.     

Reinforcing saccadic amplitude variability

Saccadic endpoint variability is often viewed as the outcome of neural noise occurring during sensorimotor processing. However, part of this variability might result from operant learning. We tested this hypothesis by reinforcing dispersions of saccadic amplitude distributions, while maintaining constant their medians. In a first experiment we reinforced the least frequent saccadic amplitudes to increase variability, and then reinforced the central part of the amplitude distributions to reduce variability. The target was placed at a constant distance from the fovea after the saccade to maintain the postsaccadic visual signal constant and an auditory reinforcement was delivered depending on saccadic amplitude. The second experiment tested the effects of the contingency. We reinforced high levels of variability in 4 participants, whereas 4 other participants were assigned to a yoked control group. On average, saccadic amplitude standard deviations were doubled while the medians remained mostly unchanged in the experimental participants in both experiments, and variability returned to baseline level when low variability was reinforced. In the control group no consistent changes in amplitude distributions were observed. These results, showing that variability can be reinforced, challenge the idea of a stochastic neural noise. We instead propose that selection processes constrain saccadic amplitude distributions.     

Individuals differ in the attentional blink: Mental speed and intra-subject stability matter

The failure to correctly report two targets (“T₁”, “T₂”) that follow each other in close temporal proximity has been called the “attentional blink” (AB). The AB has, so far, mainly been studied using experimental approaches. The present studies investigated individual differences in AB performance, revealing (among further findings) a high positive correlation between the accuracies of detecting the two targets correctly (r = 0.69); and between T₂∣T₁ accuracy and psychometric intelligence (0.41 ≤ r ≤ 0.43) and RT variability in short-term and working memory (− 0.38 ≤ r ≤ − 0.45). Together, these results support important aspects of major theoretical accounts of the AB from an individual differences perspective and introduce intelligence and intra-subject stability as contributing factors in AB performance.