Changes in auditory frequency guide visual-spatial attention

How do the characteristics of sounds influence the allocation of visual–spatial attention? Natural sounds typically change in frequency. Here we demonstrate that the direction of frequency change guides visual–spatial attention more strongly than the average or ending frequency, and provide evidence suggesting that this cross-modal effect may be mediated by perceptual experience. We used a Go/No-Go color-matching task to avoid response compatibility confounds. Participants performed the task either with their heads upright or tilted by 90°, misaligning the head-centered and environmental axes. The first of two colored circles was presented at fixation and the second was presented in one of four surrounding positions in a cardinal or diagonal direction. Either an ascending or descending auditory-frequency sweep was presented coincident with the first circle. Participants were instructed to respond to the color match between the two circles and to ignore the uninformative sounds. Ascending frequency sweeps facilitated performance (response time and/or sensitivity) when the second circle was presented at the cardinal top position and descending sweeps facilitated performance when the second circle was presented at the cardinal bottom position; there were no effects of the average or ending frequency. The sweeps had no effects when circles were presented at diagonal locations, and head tilt entirely eliminated the effect. Thus, visual–spatial cueing by pitch change is narrowly tuned to vertical directions and dominates any effect of average or ending frequency. Because this cross-modal cueing is dependent on the alignment of head-centered and environmental axes, it may develop through associative learning during waking upright experience.     

Synaesthetic associations decrease during infancy

Early development is characterized by a period of exuberant neural connectivity followed by a retraction and reweighting of connections over the course of development. It has been proposed that this connectivity may facilitate arbitrary sensory experiences in infants that are unlike anything experienced by typical adults but are similar to the sensory experiences of adults with synaesthesia, a rare sensory phenomenon that has been associated with exuberant neural connectivity and that is characterized by strong arbitrary associations between different sensations. We provide the first evidence for this infant-synaesthesia hypothesis by showing that the presence of particular shapes influences color preferences in typical 2- and 3-month-olds, but not in 8-month-olds or adults. These results are consistent with the possibility that exuberant neural connectivity facilitates synaesthetic associations during infancy that are typically eliminated during development, but that a failure of the retraction process leads in rare cases to synaesthesia in adults.     

Action selection as a guide for visual attention

We plan our actions in order to fulfil certain sensory goals. It is generally believed, therefore, that anticipation of sensory action-outcomes plays an essential role in action selection. In this study, we examined the role of action selection, prior to action execution, in the guidance of visual attention. The experiments began with an initial acquisition phase, in which participants learned to associate two actions (left/right keypress) with two visual outcomes (red/green colour). Next, participants performed in a test phase, in which they continued to select and perform the same actions while their attentional bias was measured for items that resembled the anticipated action-outcome. The findings indicate that learned action-outcome association contributes to the guidance of attention. This guidance, furthermore, was short-lived and disappeared with larger delays between action selection and execution. The findings help situate processes of visual attention in a context that includes action selection and action-outcome associative learning.     

Statistical regularities guide the spatial scale of attention

Visual scenes contain information on both a local scale (e.g., a tree) and a global scale (e.g., a forest). The question of whether the visual system prioritizes local or global elements has been debated for over a century. Given that visual scenes often contain distinct individual objects, here we examine how regularities between individual objects prioritize local or global processing. Participants viewed Navon-like figures consisting of small local objects making up a global object, and were asked to identify either the shape of the local objects or the shape of the global object, as fast and accurately as possible. Unbeknown to the participants, local regularities (i.e., triplets) or global regularities (i.e., quadruples) were embedded among the objects. We found that the identification of the local shape was faster when individual objects reliably co-occurred immediately next to each other as triplets (local regularities, Experiment 1). This result suggested that local regularities draw attention to the local scale. Moreover, the identification of the global shape was faster when objects co-occurred at the global scale as quadruples (global regularities, Experiment 2). This result suggested that global regularities draw attention to the global scale. No participant was explicitly aware of the regularities in the experiments. The results suggest that statistical regularities can determine whether attention is directed to the individual objects or to the entire scene. The findings provide evidence that regularities guide the spatial scale of attention in the absence of explicit awareness.     

Colored photisms prevent object-substitution masking in digit-color synesthesia

For C, a digit-color synesthete, viewing a digit elicits a photism (an experience of a highly specific color), which is perceived as externally projected onto the digit. We used an object substitution paradigm to demonstrate the influence of C's photisms on her perception of digits. Object substitution refers to a form of masking that depends upon two critical factors: attention must be taxed (e.g., distributed among numerous distracters), and the mask must remain on-screen for a sufficient duration after the target has been removed. Results showed that for C, even under conditions that produced maximal object substitution in control participants, her endogenous coloring of target digits prevented object substitution. Thus, the present study clearly showed that C's photisms influence her ability to detect digits.     

Induced Cross-Modal Synaesthetic Experience Without Abnormal Neuronal Connections

ABSTRACT— Are the kinds of abnormal cross-modal interactions seen in synaesthesia or following brain damage due to hyperconnectivity between or within brain areas, or are they a result of lack of inhibition? This question is highly contested. Here we show that posthypnotic suggestion induces abnormal cross-modal experience similar to that observed in congenital grapheme-color synaesthesia. Given the short time frame of the experiment, it is unlikely that new cortical connections were established, so we conclude that synaesthesia can result from disinhibition between brain areas.     

The flexibility of emotional attention: Accessible social identities guide rapid attentional orienting

There is extensive evidence that emotional-especially threatening-stimuli rapidly capture attention. These findings are often explained in terms of a hard-wired and relatively inflexible fear module. We propose an alternative, more flexible mechanism, arguing that motivational relevance is the crucial factor driving rapid attentional orienting. To test our hypothesis, we endowed initially neutral face stimuli with relevance by randomly assigning them to a social in-group or out-group during a 1-min learning phase, and used these faces as cues in a dot probe task to measure rapid attentional orienting. Across three experiments, we observed attentional orienting toward faces assigned to the out-group. Initial rapid orienting (after 100ms, Experiments 1 and 2) was observed only for familiar faces for which group membership was explicitly encoded, suggesting that rapid orienting may be based on affectively charged memory traces. At a later time point (after 500ms, Experiment 3), attention was deployed toward unfamiliar faces sharing a physical attribute (background color) with the familiar out-group faces, suggesting a more time-consuming on-line appraisal of the stimulus. The amount of attentional bias to out-group faces was correlated with individual differences in the accessibility of group identification. Our findings demonstrate that attentional prioritization mechanisms can be flexibly tuned by a brief learning phase of social identity. This is consistent with the idea that attention mechanisms subserving the selection and prioritization of emotional aspects of the environment are not static and hard-wired, but may rapidly adapt to recent changes in motivational contingencies.     

Cost of mental set reconfiguration between digits and their photisms in synaesthesia

In this study we present an experiment investigating the reconfiguration process elicited by the task switching paradigm in synaesthesia. We study the time course of the operations involved in the activation of photisms. In the experimental Group, four digit-color synaesthetes alternated between an odd-even task and a color task (to indicate the photism elicited by each digit). In both tasks, the target stimuli were numbers between 1 and 9 written in white. One of the control groups ran the same tasks but this time with colored numbers (Naive Control Group). The results of these studies showed the expected pattern for the control group in the case of regular shift: a significant task switch cost with an abrupt offset and a cost reduction in long RSI. However for the experimental group, we found switch cost asymmetry in the short RSI and non-significant cost in the long RSI. A second control group performed exactly the same tasks as the experimental group (with white numbers as targets and a second imaginary color task) -Trained Control Group-. We found no cost for this second control group. This means that the cost of mental set reconfiguration between numbers (inducers) and their photisms (concurrent sensations) occurs, that there is a specific cost asymmetry (from photisms to inducers) and that this cost cannot be explained by associative learning. The results are discussed in terms of exogenous and endogenous components of mental set reconfiguration.     

In the presence of conflicting gaze cues,fearful expression and eye-size guide attention

Humans are social beings that often interact in multi-individual environments. As such, we are frequently confronted with nonverbal social signals, including eye-gaze direction, from multiple individuals. Yet, the factors that allow for the prioritisation of certain gaze cues over others are poorly understood. Using a modified conflicting gaze paradigm, we tested the hypothesis that fearful gaze would be favoured amongst competing gaze cues. We further hypothesised that this effect is related to the increased sclera exposure, which is characteristic of fearful expressions. Across three experiments, we found that fearful, but not happy, gaze guides observers’ attention over competing non-emotional gaze. The guidance of attention by fearful gaze appears to be linked to increased sclera exposure. However, differences in sclera exposure do not prioritise competing gazes of other types. Thus, fearful gaze guides attention among competing cues and this effect is facilitated by increased sclera exposure – but increased sclera exposure per se does not guide attention. The prioritisation of fearful gaze over non-emotional gaze likely represents an adaptive means of selectively attending to survival-relevant spatial locations.     

Changing features do not guide attention in change detection: Evidence from a spatial cuing paradigm

Smilek, Eastwood, and Merikle (2000) demonstrated that the detection of change was facilitated when the target character changed in many rather than few of its features. Specifically, the function relating search response time to display set size was shallower when more features changed than when fewer features changed. The researchers interpreted these results as indicating that large feature changes provide preattentive guidance of focal attention to the location of the change. We tested this preattentive guidance hypothesis by examining change detection performance in the context of a spatial cuing paradigm. The hypothesis predicts that (1) the cost on invalidly cued trials should be less when more features change than when fewer features change, and (2) the features manipulation should have no effect on validly cued trials. In contrast to these predictions, our results show that cuing effects are equivalent across all levels of feature change and that a robust effect of the features manipulation is observable for both validly and invalidly cued trials. We argue that large feature changes do not provide preattentive guidance and in fact can be detected more readilyafter attention is already in place at the target location.     

Capturing attention when attention blinks

Four experiments addressed the question of whether attention may be captured when the visual system is in the midst of an attentional blink (AB). Participants identified 2 target letters embedded among distractor letters in a rapid serial visual presentation sequence. In some trials, a square frame was inserted between the targets; as the only geometric object in the sequence, it constituted a singleton. Capture effects obtained when the AB was most severe and when it was over were compared. There were 3 main results. First, capture occurred even when the AB was crippling, suggesting that a singleton exogenously engaged attention even when processing of a previous target was continuing apace. Second, when the singleton contained the key target feature, capture effects were clearly manifest. Third, even when the singleton did not possess the key target feature, it still succeeded in capturing attention, although the effects were both feeble and fleeting.     

Synaesthetic perception of colour and visual space in a blind subject: an fMRI case study

In spatial sequence synaesthesia (SSS) ordinal stimuli are perceived as arranged in peripersonal space. Using fMRI, we examined the neural bases of SSS and colour synaesthesia for spoken words in a late-blind synaesthete, JF. He reported days of the week and months of the year as both coloured and spatially ordered in peripersonal space; parts of the days and festivities of the year were spatially ordered but uncoloured. Words that denote time-units and triggered no concurrents were used in a control condition. Both conditions inducing SSS activated the occipito-parietal, infero-frontal and insular cortex. The colour area hOC4v was engaged when the synaesthetic experience included colour. These results confirm the continued recruitment of visual colour cortex in this late-blind synaesthetes. Synaesthesia also involved activation in inferior frontal cortex, which may be related to spatial memory and detection, and in the insula, which might contribute to audiovisual integration related to the processing of inducers and concurrents.     

Free-swinging attention

Psychoanalytic listening enlists the analyst's capacity for, and relative comfort in, rapidly shifting levels of attention and organization. Such shifts are not effortless and can be characterized as part of "free-swinging attention," a term that suggests some dimensions of the analyst's work. The need to establish meaning in the individual and immediate context parallels the task of a child in learning language, and the role of the analyst as child is an important if usually overlooked one. The author compares psychoanalytic with psychotherapeutic listening, as well as some current views on free association and evenly suspended attention.     

Central-cue discriminability modulates object-based attention by influencing spatial attention

The role of central-cue discriminability in modulating object-based effects was examined using Egly, Driver, and Rafal's (1994) "double-rectangle" spatial cueing paradigm. Based on the attentional focusing hypothesis (Goldsmith & Yeari, 2003), we hypothesized that highly discriminable central-arrow cues would be processed with attention spread across the two rectangles (potential target locations), thereby strengthening the perceptual representation of these objects so that they influence the subsequent endogenous deployment of attention, yielding object-based effects. By contrast, less discriminable central-arrow cues should induce a more narrow attentional focus to the center of the display, thereby weakening the rectangle object representations so that they no longer influence the subsequent attentional deployment. Central-arrow-cue discriminability was manipulated by size and luminance contrast. The results supported the predictions, reinforcing the attentional focusing hypothesis and highlighting the need to consider central-cue discriminability when designing experiments and in comparing experimental results.