This project aims to investigate the mechanisms of dynamic re-scaling of visual attentional focus. Such changes are critical for task performance, yet to date almost nothing is known about the processes underlying them, other than that they can be slow. Using an innovative cognitive psychology approach integrating individual-differences, experimental, and training frameworks, this project expects to generate new theoretical knowledge about attentional rescaling and insights into how to improve it. The expected practical outcomes include selection and training programs for specific contexts (e.g., athletes). This should provide significant economic benefits, such as optimising performance prior to other costly forms of training.

Project Aims & Background

For most people, vision is the primary sensory modality, allowing us to navigate through the world and interact with it. It is our means of driving safely through traffic, avoiding obstacles, perceiving food we want to eat, reading, and recognising the face of a loved one. But at any given moment, there is far more information available to process in visual scenes than our brain is capable of processing to the level of awareness. This means that visual attention has a fundamental triaging role to play in shaping our perception of the world, by selecting certain relevant information for privileged processing, while filtering out other information.

In many real-world visual tasks, the size of the spatial area over which we apply our attentional resources is important. For example, when driving a car, reading the speedometer requires a narrow focus of spatial attention, whereas monitoring the road for any movement (e.g., child approaching the road, trajectories of other cars) requires a broad focus. Similarly, when watching a crowd of people, recognising an individual face requires a narrow focus of

attention, while determining the direction in which the majority of the crowd is moving requires a broader one. Laboratory research has confirmed that different attended-region sizes benefit different aspects of visual perception. For example, a narrow attended-region enhances perceptual acuity for fine spatial details (Goodhew et al [1]), whereas a wide one facilitates visual search over multiple diverse objects [2]. Crucially, the fact that different attended-region sizes are variably optimal for particular tasks implies that to successfully support dynamic and complex real-world vision, a critical task is not just to set a size for spatial attention, but to be able to flexibly alter (i.e., switch) this size in a rapid and efficient fashion. For example, attentional re-sizing underlies being able to quickly alter attended-region size from narrow focus on the speedo to broad focus on the whole scene to avoid collisions.

To date, essentially nothing is known about this process of flexibly altering attended region size (although researchers have a well-developed knowledge about the mechanisms involved in shifting attention to new locations in space without altering size). Indeed, in stark contrast to the apparent functional requirements of real world vision, some evidence suggests that altering attended-region size can be a surprisingly slow process – in the order of several seconds [3, 4] – in contrast to many other attentional processes that occur within several hundred milliseconds. The purpose of this project is to elucidate the mechanisms involved in attentional re-sizing, and to examine whether its efficiency can be improved.

First goal

The first goal of the project is to test some broad-level theoretical ideas about how the process of attentional re-sizing works. Given the almost complete lack of current theoretical knowledge, I will begin by examining the question at the broadest possible level, asking whether attentional re-sizing is regulated by cognitive control (i.e., executive function) resources, akin to those that govern the general ability to flexibly alter response rules (e.g., as instantiated in the classic Wisconsin Card Sorting Test [5]. The likely role of executive control in attentional re-sizing is suggested by the apparent slowness of the process [3,4], and also the functional similarity (e.g., requirement for selection, switching, and inhibition) between attentional resizing and classic executive functions.

Furthermore, I will examine whether attentional re-sizing is more efficient than the evidence to date would suggest – for certain classes of objects. That is, there is substantial evidence that certain classes of stimuli (e.g., faces, emotionally-evocative images) have special significance in attracting attention [e.g., 7,8]. Given this special relationship between attention and stimuli with intrinsic social or emotional significance, one possible reason for the apparent slowness of attentional re-sizing is that to date all of the studies have used well-controlled but simplistic and impoverished stimuli (e.g., rectangles) in order to induce attentional re-sizing. Here, therefore, I will assess whether attentional re-sizing efficiency is constant for an individual, or varies across different types of objects.

The second goal

THE SECOND GOAL of the project is to understand whether attentional re-sizing efficiency is the same for all people, or shows individual differences, and whether it can be improved by training. Previous literature shows that default size (size of attended region adopted or preferred in the absence of explicit task demands) varies across people [11, 12, 13]. Default size and efficiency may be related, such that efficiency is asymmetric dependent on default size, with individuals that have a small default having more difficulty expanding than contracting (as has been reported in schizophrenia [10]), and vice versa. This therefore implies that efficiency of re-sizing might also vary systematically across individuals. This raises the practical question of whether some individuals are more suitable for attention-critical jobs than others (e.g., ambulance drivers). Moreover, can experience – and therefore in particular training, improve attentional re-sizing efficiency? There is no direct evidence on this, but there are several indirect lines of evidence to suggest so. Evidence indicates that life experience may alter default size: expert soccer-players have a broader attended region along the horizontal dimension than controls, while expert volleyball players have a broader attended-region along the vertical dimension, patterns consistent with the likely ball locations in each sport [14]. It could be that individuals with these attended-region sizes naturally excel in these pursuits. Or, it could be that training in these sports alters the individual’s default or preferred attended-region size. Given the preliminary evidence to suggest that default size may relate to re-sizing efficiency [10], I will thus test whether experience – instantiated as laboratory training of attention – can improve efficiency of re-sizing spatial attention (e.g., in elite athletes).

Methodologically, the two goals will be addressed by a combination of behavioral experiments (e.g., experimentally manipulating task demands to compel attentional re-sizing), EEG, individual-difference studies correlating a person’s re-sizing ability with their executive resources and default attentional size, and training studies.

References

1. Goodhew, Shen, & Edwards. (2016). Psychonomic Bulletin & Review, 23, 1144-1149.
2. Greenwood & Parasuraman (2004). Perception & Psychophysics, 66, 3-22.
3. Robertson (1996). Journal of Experimental Psychology: General, 125, 227-249.
4. Hubner (2000). Visual Cognition, 7, 465-484.
5. Diamond (2013). Annual Review of Psychology, 64, 135-168.
6. Muller etal. (2003). Journal of Neuroscience, 23, 3561-3565.
7. Awh etal. (2004). Cognitive Psychology, 48, 95-126.
8. Anderson. (2005). Journal of Experimental Psychology: General, 134, 258-281.
9. Von Muhlenen & Lleras. (2007). Journal of Experimental Psychology: Human Perception and Performance, 33, 1297-1310.
10. Elahipanah, Christensen, & Reingold (2011). Neuropsychologia, 49, 3370-3376.
11. McKone etal (2010). Vision Research, 50, 1540-1549.
12. Wilson et al. (2016). Attention, Perception, & Psychophysics, 78, 209-217.
13. Phillips, Chapman, & Berry. (2004). Perception, 33, 79-86.
14. Huttermann, Memmert, & Simons (2014). Journal of Experimental Psychology: Applied, 20, 147-157.

Funding

Australian Research Council Future Fellowship awarded to Stephanie Goodhew

Websites for updates on outputs

Stephanie Goodhew

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