It’s only when you focus your attention on a solitary voice, blocking out all other extraneous sound, that you can begin to process the information in a meaningful way. We hear multiple voices, but can’t distinguish or understand any single one. Taking in everything at once results in sensual overload.Īurally, the cumulative result of every voice creates a wave of indistinguishable noise. Groups of colorfully dressed people and flashing lights, dozens of conversations happening simultaneously, the smell of hors d’oeuvres mixed with perfume, and a wave of heat emanating from a crowd of excited people. Think back to the last time you were in a crowded room at a loud party. It’s only by ignoring other streams of incoming information that we can actually process the small piece of information that we’re focusing on. It implies withdrawal from some things in order to deal effectively with others, and is a condition which has a real opposite in the confused, dazed, scatterbrained state which in French is called distraction, and Zerstreutheit in German.Īttention is essential for taking in information, but it comes at a cost: we can only focus our attention on one piece of information at a time. Focalization, concentration, of consciousness are of its essence. It is the taking possession by the mind, in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought. The famed psychologist William James describes attention as such:Įveryone knows what attention is. It’s true that we can experience a multitude of stimuli at once, but focusing our mind and differentiating between these stimuli requires a very special skill – attention. Sights, sounds, smells, and tactile sensations come at us from every angle, vying for a precious scrap of our cognitive awareness.ĭespite our best efforts, we simply can’t take in all of this information.
The authors have declared no competing interest.Hey, did you just hear that? Look, did you just see that? Wait, can you feel that? What’s that smell? Wait…what?! On a daily basis our senses are bombarded with information. Collectively our results suggest a “selective listening” model in which both actively protruding cell fronts and actively retracting cell rears have strong commitment to their current migratory program. Finally, optogenetic attempts to reverse cell decisions reveal that, once an edge begins retracting, it commits to this fate, with the kinase ROCK limiting its sensitivity to inputs until the retraction is complete. Furthermore, we use optogenetic tools to show that receptor inputs only bias the decision similarly late, once mechanical stretching begins to weaken each front. Using supervised statistical learning, we demonstrate that cells commit to one leading edge late in the decision- making process, rather than amplifying early pre-existing asymmetries. Here we challenge chemotaxing HL60 neutrophil-like cells with symmetric bifurcating microfluidic channels, enabling us to probe the cell-intrinsic properties of their decision-making process.
As neutrophils navigate complex environments to reach sites of infection, they may encounter obstacles that force them to split their front into multiple leading edges, raising the question of how the cell selects which front to maintain and which front(s) to abandon.