Attention can drive visual search/perception, but I think it's important to resist too many intuition driven compartmentalization of the (only-?) seemingly independent subprocesses at work. I won't push my politics on you too hard, but I'd like to share a few refs that may be illustrative of how diverse the perspectives can be:

http://journal.frontiersin.org/Journal/10.3389/fnhum.2013.00361/abstract

https://www.researchgate.net/publication/41012320_Interactions_dominate_the_dynamics_of_visual_cognition?ev=prf_pub

https://www.researchgate.net/publication/232064792_Gaze_fluctuations_are_not_additively_decomposable_Reply_to_Bogartz_and_Staub?ev=prf_pub

http://www.haskins.yale.edu/Reprints/HL0208.pdf

What you'll find is that the visual experience unfolds rather messily (but fluidly, I think) across retinal/physiological particulars, contextual particulars, and cognitive particulars. Welcome to this fascinating research problem!

Best of luck with your psychology program!

Article Interactions Dominate the Dynamics of Visual Cognition

Article Gaze fluctuations are not additively decomposable: Reply to ...

I would say that attention has both top-down characteristics (as when you are looking for the place where you left your glasses) and bottom-up characteristics (as when your attention is being drawn by an unexpected color, shape or sound in the outside world).

Both types of attention can influence where you look (search or scan) and what you see as a result (perception). Of course, perception can also operate without attention. However, in those circumstances perception often is unconscious, as when you notice a familiar building when you are driving back home, without being aware of it.

To complicate things a bit more: attention can also be directed on parts of the visual scene without moving your eyes (covert attention). So attention does not need visual (overt) search for it to result in changing perceptions.

I realize this is a rather theoretical answer, but I am sure there are many good marketing and communication books out there that can help you apply this knowledge to real-life scenarios!

Good luck!

It is common assumption that particular features are so elementary to the visual system that no requirement for attentional resources to be perceived. Orientation, colour or size differences are seen as a preattentive features where by no attentional resources is required in perceiving these properties. However, it has been demonstrated that attention can be critical for the detection of our preattentive properties.

I think the attention you described are more of the subjective attention, i.e. Top-down process, mentioned by Karel. Whereas the question you asked are more relevant to the bottom-up process. In that sense, you might want to check the studies on "subliminal stimuli", which go through to your brain without awareness:

http://en.wikipedia.org/wiki/Subliminal_stimuli

You can also google Disney or Coca Cola for their suspected use of subliminal stimuli to embed information in their adverts.

Hope these help.

Body guards of politicians conduct visual search for suspicious people in the crowd, but pay zero attention to the nonsense that their boss is saying in the speech.

Thanks for this interesting point Cheng-Hung Lo. Would you say advertisers use subliminal stimuli to capture their audience and is it a conscious decision to integrate such stimuli in advertising?

Mikhail this is a simple and straight forward explanation, but would you then say they are attending to visual search while consciously disregarding the contexts of the speech because they see that to be less important?

An extremely interesting and complicated question. But yes, the allocation of "attentional resources" is both "top-down" and "bottom up."

humans are extremely dependent upon the visual system; however, an additional issue concerns the theories that explpore how systems interact. For example, one popular theory is that in humans, the auditory system serves the purpose of orienting the visual system. A concrete example - the crack of a ball hitting a bat orients the outfielder where to look for the ball; in fact, in sports performance psychology, these interactions are stressed.

"top down" attention, or explicit visual attention, is presumably mediated by the ventral attention network alerting the dorsal network to orient vision through control of the frontal eye fields. This is necessary under conditions of novelty detection; implicit visual attention is always operant under "lighted" conditions; we learn a great deal about the world, and each other, simply through implicit observations. In conditions of darkness, the auditory system continues to identify and locate through vrentral and dorsal pathways; for another example, consider sitting in your office, with the door closed - when someone walks by, you can actually identify that person by the pattern of walking..., and orient to that sound if you decide to do so.

It is very notable that sensory systems are organized in parallel, with considerable interaction between systems; ventral auditory and visual pathways support object identity anf the "reward value" or usefulness on these "objects." dorsal pathways support the orientation of attention throuigh frontal eye field-parietal lobe interactions. Auditory pathways actually send projections to primary visual brain regions, such as v1 and v2 of the occipital lobes; auditory and visual systems also interact through occipital-parietal-temporal lobe association areas. Several studies demonstrate that that even on auditory tasks, occipital lobes are robustly activated, and this activation cannot be explained on the basis of visual functioning; instead, auditory input implicitly evokes images to assist in task performance. The large scale brain system studies by people such as yeo, et al, circa 2010, castellanos and proal, 2012, and cortese, et al, 2012 are quite compelling in identifying a ventral attention network with visual and auditory pathways following similar connectional profiles, a dorsal attention network organized along the same dorsal pathways for auditory and visual information, while both ventral and auditory systems are supported by the visual attention network occipital lobe "hub." i recently posted a paper on this site titled the neuropsychology of attention just a few days ago - i am simply referring you to that paper because of the references to yeo, castellanos, cortese, naatanan, and salmi; you should be able to locate them very easily from that bibliography. I'm sorry the reply seems a bit off track, but..., the question really isn't as simple as it sounds. As you explore the "visual system" more deeply, these interactions become readily apparent; the "end point" is a hierarchically organized system of cognitive control, simplifed by a system of dual-tiered behavioral organization, as we constantly "shift" between automatic behaviors which are typically implicit, alternating with episodes of more explicit cognitive re-direction of behavior as situaions develop or unfold. It is easier to understand a dual-tierd system in a brief reply than it is to explain a cognitive-behavioral hierarchy; new adjustments are made, and new behaviors are learned in an ongoing way, so the "hierarchy" is really characterized by a changing balance between explicit and implicit locus of control, a process referred to as "novelty-routinization" by people such as e. Goldberg and his associates, lovell and pddell.

Lk

I think that a simple case would be driving a car. You can be paying attention to someone you're talking to, or thinking about some problem, listening to music, eating burgers, and totally ignoring the details of what's going on the road, and yet be totally ready to react to something happening on the road. It seems in this case, driving is an automatic process that clearly requires scanning of the road etc., but this probably occurs at a subconscious level. Whether that counts as attention perhaps depends on your definition of attention and whether it only includes conscious processes.

Thank you for the concise reply; if interest in attention and explicit/implicit processes in driving adaptive behavior, see "neural basis of motivational and cognitive control," mars, r., sallet, j, rushworth, m., and yeung, n (eds), mit press, 2-11.

Sorry; that year should be 2011.

To Tracey,

The purpose of using subliminal stimuli in adverts is more about "captivating" but "capturing" the customers. The concept is interesting in its own right but probably more subtle and complicated then the answer you're looking for. My current understanding of the question on your mind is more about the strategies that ad company use to grab our visual attention, e.g. how to make an ad stand out of the crowd.

Imagine this scenario: On the bulletin board on your campus, lots of posters fill up the space. All of them are ads with rectangular shapes, in the same size, and aligned nice and clean in rows and columns. If I am to replace one of them with my ad poster and hope it to get noticed instantly, I will use a circular shape poster, or, apply some design tricks to make it look like a circular shape (e.g. put all my information within a circular foreground and make the background the same color as the bulletin board). In this example, I can say that I utilize the preattentive feature detection mechanism in the visual system to make my poster stand out of the crowd. That is, contour/shape features are preattentive and the difference in the poster shape will arouse more of the feature detection network.

If you understand the above example, I believe you can think of other examples with the differences in colors, lightness, movements. Then I guess it is much easier for you now to "analytically" see how they work in adverts.

Hope this help.

I haven't read all of the other responses so this answer may be redundant. Attention is a very complicated process. I suggest that you read the Purves' et al. text book on Cognitive Neuroscience. An example of a unresolved issue in attention (unless it has recently been resolved) is the Binding problem. Of course, some researchers think it isn't a problem.

Attention is viewed by some researchers as an emergent process. There are many, many papers on attention. You might also want to look at one of the Annual Reviews in Cognitive Psychology.