Insular Cortex Mediates Attentional Capture by Behaviorally Relevant Stimuli after Damage to the Right Temporoparietal Junction

The right temporoparietal junction (rTPJ) and insula both play a key role for the processing of relevant stimuli. However, while both have been conceived as neural “switches” that detect salient events and redirect the focus of attention, it remains unclear how these brain regions interact to achieve this behavioral goal. Here, we tested human participants with focal left-hemispheric or right-hemispheric lesions in a spatial cuing task that requires participants to react to lateralized stimuli preceded by a distracter that shares or does not share a relevant feature with the target. Using machine learning to identify significant lesion–behavior relationships, we found that rTPJ damage produces distinctive, pathologically increased attentional capture, but only by relevant distracters. Functional connectivity analyses revealed that the degree of capture is positively associated with a functional connection between insula and rTPJ, together with functional isolation of the rTPJ from right dorsal prefrontal cortex (dPFC). These findings suggest a mechanistic model where the insula–rTPJ connection constitutes a crucial functional unit that breaks attentional focus upon detection of behaviorally relevant events, while the dPFC appears to attune this activity.

Simultaneous Modeling of Reaction Times and Brain Dynamics in a Spatial Cuing Task

Understanding how brain activity translates into behavior is a grand challenge in neuroscientific research. Simultaneous computational modeling of both measures offers to address this question. The extension of the dynamic causal modeling (DCM) framework for BOLD responses to behavior (bDCM) constitutes such a modeling approach. However, only very few studies have employed and evaluated bDCM, and its application has been restricted to binary behavioral responses, limiting more general statements about its validity.This study used bDCM to model reaction times in a spatial attention task, which involved two separate runs with either horizontal or vertical stimulus configurations. We recorded fMRI data and reaction times (n=29) and compared bDCM to classical DCM and a behavioral Rescorla-Wagner model using goodness of fit-statistics and machine learning methods.Data showed that bDCM performed equally well as classical DCM when modeling BOLD responses and better than the Rescorla Wagner model when modeling reaction times. Notably, only using bDCM’s parameters enabled classification of the horizontal and vertical runs suggesting that bDCM seems to be more sensitive than the other models. Although our data also revealed practical limitations of the current bDCM approach that warrant further investigation, we conclude that bDCM constitutes a promising method for investigating the link between brain activity and behavior.

The Nature of Unconscious Attention to Subliminal Cues

Attentional selection in humans is mostly determined by what is important to them or by the saliency of the objects around them. How our visual and attentional system manage these various sources of attentional capture is one of the most intensely debated issues in cognitive psychology. Along with the traditional dichotomy of goal-driven and stimulus-driven theories, newer frameworks such as reward learning and selection history have been proposed as well to understand how a stimulus captures attention. However, surprisingly little is known about the different forms of attentional control by information that is not consciously accessible to us. In this article, we will review several studies that have examined attentional capture by subliminal cues. We will specifically focus on spatial cuing studies that have shown through response times and eye movements that subliminal cues can affect attentional selection. A majority of these studies have argued that attentional capture by subliminal cues is entirely automatic and stimulus-driven. We will evaluate their claims of automaticity and contrast them with a few other studies that have suggested that orienting to unconscious cues proceeds in a manner that is contingent with the top-down goals of the individual. Resolving this debate has consequences for understanding the depths and the limits of unconscious processing. It has implications for general theories of attentional selection as well. In this review, we aim to provide the current status of research in this domain and point out open questions and future directions.

Attention Drives Emotion: Voluntary Visual Attention Increases Perceived Emotional Intensity

Attention and emotion are fundamental psychological systems. It is well established that emotion intensifies attention. Three experiments reported here ( N = 235) demonstrated the reversed causal direction: Voluntary visual attention intensifies perceived emotion. In Experiment 1, participants repeatedly directed attention toward a target object during sequential search. Participants subsequently perceived their emotional reactions to target objects as more intense than their reactions to control objects. Experiments 2 and 3 used a spatial-cuing procedure to manipulate voluntary visual attention. Spatially cued attention increased perceived emotional intensity. Participants perceived spatially cued objects as more emotionally intense than noncued objects even when participants were asked to mentally rehearse the name of noncued objects. This suggests that the intensifying effect of attention is independent of more extensive mental rehearsal. Across experiments, attended objects were perceived as more visually distinctive, which statistically mediated the effects of attention on emotional intensity.

Multisensory Integration and Exogenous Spatial Attention: A Time-window-of-integration Analysis

Although it is well documented that occurrence of an irrelevant and nonpredictive sound facilitates motor responses to a subsequent target light appearing nearby, the cause of this “exogenous spatial cuing effect” has been under discussion. On the one hand, it has been postulated to be the result of a shift of visual spatial attention possibly triggered by parietal and/or cortical supramodal “attention” structures. On the other hand, the effect has been considered to be due to multisensory integration based on the activation of multisensory convergence structures in the brain. Recent RT experiments have suggested that multisensory integration and exogenous spatial cuing differ in their temporal profiles of facilitation: When the nontarget occurs 100–200 msec before the target, facilitation is likely driven by crossmodal exogenous spatial attention, whereas multisensory integration effects are still seen when target and nontarget are presented nearly simultaneously. Here, we develop an extension of the time-window-of-integration model that combines both mechanisms within the same formal framework. The model is illustrated by fitting it to data from a focused attention task with a visual target and an auditory nontarget presented at horizontally or vertically varying positions. Results show that both spatial cuing and multisensory integration may coexist in a single trial in bringing about the crossmodal facilitation of RT effects. Moreover, the formal analysis via time window of integration allows to predict and quantify the contribution of either mechanism as they occur across different spatiotemporal conditions.

Contingent Attentional Engagement: Stimulus- and Goal-Driven Capture Have Qualitatively Different Consequences

We examined whether shifting attention to a location necessarily entails extracting the features at that location, a process referred to as attentional engagement. In three spatial-cuing experiments ( N = 60), we found that an onset cue captured attention both when it shared the target’s color and when it did not. Yet the effects of the match between the response associated with the cued object’s identity and the response associated with the target (compatibility effects), which are diagnostic of attentional engagement, were observed only with relevant-color onset cues. These findings demonstrate that stimulus- and goal-driven capture have qualitatively different consequences: Before attention is reoriented to the target, it is engaged to the location of the critical distractor following goal-driven capture but not stimulus-driven capture. The reported dissociation between attentional shifts and attentional engagement suggests that attention is best described as a camera: One can align its zoom lens without pressing the shutter button.