The Importance of Attention in the Twinkle Goes Effect

How do we perceive the location of moving objects? The position and motion literature is currently divided. Predictive accounts of object tracking propose that the position of moving objects is anticipated ahead of sensory signals, whilst non-predictive accounts claim that an anticipatory mechanism is not necessary. A novel illusion called the twinkle goes effect, describing a forward shift in the perceived final location of a moving object in the presence of dynamic noise, presents a novel opportunity to disambiguate these accounts. Across three experiments, we compared the predictions of predictive and non-predictive theories of object tracking by combining the twinkle goes paradigm with a multiple object tracking task. Specifically, we tested whether the size of the twinkle goes illusion would be smaller with greater attentional load (as entailed by the non-predictive, tracking continuation theory) or whether it would not be affected by attentional load (as entailed by predictive extrapolation theory). Our results failed to align with either of these theories of object localisation and tracking. Instead, we found evidence that the twinkle goes effect may be stronger with greater attentional load. We discuss whether this result may be a consequence of an essential, but previously unexplored relationship between the twinkle goes effect and representational momentum. In addition, this study was the first to reveal critical individual differences in the experience of the twinkle goes effect, and in the mislocalisation of moving objects. Together, our results continue to demonstrate the complexity of position and motion perception.

Learning at Variable Attentional Load Requires Cooperation of Working Memory, Meta-learning and Attention-augmented Reinforcement Learning

Flexible learning of changing reward contingencies can be realized with different strategies. A fast learning strategy involves using working memory of recently rewarded objects to guide choices. A slower learning strategy uses prediction errors to gradually update value expectations to improve choices. How the fast and slow strategies work together in scenarios with real-world stimulus complexity is not well known. Here, we aim to disentangle their relative contributions in rhesus monkeys while they learned the relevance of object features at variable attentional load. We found that learning behavior across six monkeys is consistently best predicted with a model combining (i) fast working memory and (ii) slower reinforcement learning from differently weighted positive and negative prediction errors as well as (iii) selective suppression of nonchosen feature values and (iv) a meta-learning mechanism that enhances exploration rates based on a memory trace of recent errors. The optimal model parameter settings suggest that these mechanisms cooperate differently at low and high attentional loads. Whereas working memory was essential for efficient learning at lower attentional loads, enhanced weighting of negative prediction errors and meta-learning were essential for efficient learning at higher attentional loads. Together, these findings pinpoint a canonical set of learning mechanisms and suggest how they may cooperate when subjects flexibly adjust to environments with variable real-world attentional demands.

Attentional Load Effects on Emotional Content in Face Working Memory

This study investigated the role of attentional resources in processing emotional faces on working memory (WM). Participants memorised two face arrays with the same emotion but different identities and were required to judge whether the test face had the same identity as one of the previous faces. Concurrently during encoding and maintenance, a sequence of high-or-low pitched tones (high load) or white noise bursts (low load) was presented, and participants were required to count how many low-tones were heard. Experiment 1 and 2 used an emotional and neutral test face, respectively. The results revealed a significant WM impairment for sad and angry faces in the high load vs low load condition but not for happy faces. Happy faces were better recognised than other emotional faces in a high load. In Experiment 1, participants remembered better happy faces than other emotional faces. In contrast, Experiment 2 showed that performance was poorer for happy than sad faces but not for angry faces. This evidence suggests that depleting of attentional resources affects less WM for happy faces than other emotional faces, but also differential effects on WM for emotional faces depend on the presence or absence of emotion face at retrieval.

The ascending arousal system promotes optimal performance through meso-scale network integration in a visuospatial attentional task

Previous research has shown that the autonomic nervous system provides essential constraints over ongoing cognitive function. However, there is currently a relative lack of direct empirical evidence for how this interaction manifests in the brain at the macro-scale level. Here, we examine the role of ascending arousal and attentional load on large-scale network dynamics by combining pupillometry, functional MRI and graph theoretical analysis to analyze data from a visual motion-tracking task with a parametric load manipulation. We found that attentional load effects were observable in measures of pupil diameter and in a set of brain regions that parametrically modulated their BOLD activity and meso-scale network-level integration. In addition, the regional patterns of network reconfiguration were correlated with the spatial distribution of the α2a adrenergic receptor. Our results further solidify the relationship between ascending noradrenergic activity, large-scale network integration, and cognitive task performance.

Sustained Auditory Attentional Load Decreases Audiovisual Integration in Older and Younger Adults

The modulation of attentional load on the perception of auditory and visual information has been widely reported; however, whether attentional load alters audiovisual integration (AVI) has seldom been investigated. Here, to explore the effect of sustained auditory attentional load on AVI and the effects of aging, nineteen older and 20 younger adults performed an AV discrimination task with a rapid serial auditory presentation task competing for attentional resources. The results showed that responses to audiovisual stimuli were significantly faster than those to auditory and visual stimuli ( AV > V ≥ A , all p < 0.001 ), and the younger adults were significantly faster than the older adults under all attentional load conditions (all p < 0.001 ). The analysis of the race model showed that AVI was decreased and delayed with the addition of auditory sustained attention ( no _ load > load _ 1 > load _ 2 > load _ 3 > load _ 4 ) for both older and younger adults. In addition, AVI was lower and more delayed in older adults than in younger adults in all attentional load conditions. These results suggested that auditory sustained attentional load decreased AVI and that AVI was reduced in older adults.