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Abstract Previous work shows that automatic attention biases toward recently selected target features transfer across action and perception and even across different effectors such as the eyes and hands on a trial-by-trial basis. Although these findings suggest a common neural representation of selection history across effectors, the extent to which information about recently selected target features is encoded in overlapping versus distinct brain regions is unknown. Using fMRI and a priming of pop-out task where participants selected unpredictable, uniquely colored targets among homogeneous distractors via reach or saccade, we show that color priming is driven by shared, effector-independent underlying representations of recent selection history. Consistent with previous work, we found that the intraparietal sulcus (IPS) was commonly activated on trials where target colors were switched relative to those where the colors were repeated; however, the dorsal anterior insula exhibited effector-specific activation related to color priming. Via multivoxel cross-classification analyses, we further demonstrate that fine-grained patterns of activity in both IPS and the medial temporal lobe encode information about selection history in an effector-independent manner, such that ROI-specific models trained on activity patterns during reach selection could predict whether a color was repeated or switched on the current trial during saccade selection and vice versa. Remarkably, model generalization performance in IPS and medial temporal lobe also tracked individual differences in behavioral priming sensitivity across both types of action. These results represent a first step to clarify the neural substrates of experience-driven selection biases in contexts that require the coordination of multiple actions. 

Abstract Many daily activities require performance of multiple tasks integrating cognitive and motor processes. While the fact that both processes go through deterioration and changes with aging has been generally accepted, not much is known about how aging interacts with stages of motor skill acquisition under a cognitively demanding situation. To address this question, we combined a visuomotor adaptation task with a secondary cognitive task. We made two primary findings beyond the expected age-related performance deterioration. First, while young adults showed classical dual-task cost in the early motor learning phase dominated by explicit processes, older adults instead strikingly displayed enhanced performance in the later stage, dominated by implicit processes. For older adults, the secondary task may have facilitated a shift to their relatively intact implicit learning processes that reduced reliance on their already-deficient explicit processes during visuomotor adaptation. Second, we demonstrated that consistently performing the secondary task in learning and re-learning phases can operate as an internal task-context and facilitate visuomotor memory retrieval later regardless of age groups. Therefore, our study demonstrated age-related similarities and differences in integrating concurrent cognitive load with motor skill acquisition which, may in turn, contributes to the understanding of a shift in balance across multiple systems. 

Action is an important arbitrator as to whether an individual or a species will survive. Yet, action has not been well integrated into the study of psychology. Action or motor behavior is a field apart. This is traditional science with its need for specialization. The sequence in a typical laboratory experiment of see → decide → act provides the rationale for broad disciplinary categorizations. With renewed interest in action itself, surprising and exciting anomalous findings at odds with this simplified caricature have emerged. They reveal a much more intimate coupling of vision and action, which we describe. In turn, this prompts us to identify and dwell on three pertinent theories deserving of greater notice. 

Orientation sensitivity is a fundamental property of the visual system, but not all orientations are created equal. For instance, radially oriented stimuli, aligned with a line intersecting the center of gaze, produce greater activity throughout the visual cortex and are associated with greater perceptual sensitivity compared with other orientations. Here, we discuss a robust visual illusion that is likely related to this preference. Using a continuous response measure, participants ( N = 36 adults) indicated the gap position in a peripheral Landolt C placed in one of eight orientations and eight locations along four meridians (vertical, horizontal, 45°, 135°). The error distributions revealed that the perceived gap was attracted toward the radial axis. For instance, the gap in a regular C would often be wrongly perceived as tilted 45° corresponding to the oblique meridian where it was placed. These findings demonstrate an unsuspected early-vision influence on the perceived orientation of an object. 

One of the brain’s primary functions is to promote actions in dynamic, distracting environments. Because distractions divert attention from our primary goals, we must learn to maintain accurate actions under sensory and cognitive distractions. Visuomotor adaptation is a learning process that restores performance when sensorimotor capacities or environmental conditions are abruptly or gradually altered. Prior work showed that learning to counteract an abrupt perturbation under a particular single- or dual-task setting (i.e., attentional context) was associated with better recall under the same conditions. This suggested that the attentional context was encoded during adaptation and used as a recall cue. The current study investigated whether the attentional context (i.e., single vs. dual task) also affected adaptation and recall to a gradual perturbation, which limited awareness of movement errors. During adaptation, participants moved a cursor to a target while learning to counteract a visuomotor rotation that increased from 0° to 45° by 0.3° each trial, with or without performing a secondary task. Relearning was impaired when the attentional context was different between adaptation and recall ( experiment 1), even when the exposure to the attentional context was limited to the early or late half of adaptation ( experiment 2). Changing the secondary task did not affect relearning, indicating that the attentional context, rather than specific stimuli or tasks, was associated with better recall performance ( experiment 3). These findings highlight the importance of cognitive factors, such as attention, in visuomotor adaptation and have implications for learning and rehabilitation paradigms. NEW & NOTEWORTHY Adaptation acquired under single- or dual-task setting, which created an undivided or divided attentional context, respectively, was impaired when relearning occurred under different conditions (i.e., shifting from a dual to single task). Changes to the attentional context impaired relearning when the initial adaptation was to a gradual perturbation. Explicit awareness of the perturbation was not necessary for this effect to be robust, nor was the effect attributable to changes in the secondary task requirements.