Paying attention is hard

Most of you are probably thinking that I’m talking about Attention deficit hyperactivity disorder, also known as ADHD, but the fact is: paying attention to something is a complex function your brain needs to perform because of the connection to several aspects of perception.

Keeping your attention and focus depends on many factors and there are a lot of models, proposed by different authors, about how, in fact, our ability to retain attention indeed works.

The external stimuli are not, by themselves, enough to keep our attention. Then, what is necessary to be able to do so?

Broadbent’s filter model of attention

Broadbent was the first one to actually propose an explanation as to how our attention works. According to him, the stimuli would activate the sensory filter, which would make our attention act. Then, there would be two possible paths: storing the information for a latter response or processing the information immediately.

This model defended that we weren’t able to process more than one information at a given time. It was rapidly refuted.

Attenuation theory

Anne Treisman had also proposed a model of selective attention, where she talked about two filters for the external stimuli and it claims that these don’t work as a barrier for external stimuli, but an attenuation instead. So, you can also extract meaningful content from the irrelevant inputs filtered.

This model is seen as an upgrade from Broadbent’s, yet, despite these new ideas, it still wasn’t enough to explain the whole complexity of our ability to focus attention on something.

Kahneman Model of Attention

Kahneman proposed an even more evolved model which was based around the idea of mental efforts. The stimuli are, in fact, dependent on a lot of factors. They could be internal or external and they depended on the specific circumstances of one specific moment.

These stimulus may, or may not, have had the ability to activate the information processor which is central in this model. Our ability of focus our attention and process the information will therefore depend of the stimulus themselves, our availability (which could be affected, for example, by our emotions or how tired we are) and the context where the stimuli occurs.

Mackworth and Sustain Attention

Mackworth centered his experiments in vigilance, which means the ability of maintaining or sustaining focused attention for prolonged periods of time.

He begins his experiments during World War II and he wanted to learn how to keep a person in a state of vigilance for a longer period of time. He determined some factors that had a great impact on this ability.

The first one was the individual’s personality and his will to keep focused and attentive. Afterwords, he pointed out that another great factor were stimulants or drugs, such as coffee, which, according to his experiments, were of great help.

According to his theories, the stimulation itself and its characteristics are also important, the presence of an hierarchical superior or a ringing phone in irregular periods of time are usually quite effective in keeping attention for longer periods of time.

The last factor he pointed out was knowing the results, which roughly translates into the fact that a person will more easily keep attention on her task if she knows how well it’s going. Knowing that something is working, will definitely keep the person focused and active for.


The ability of focus our attention depends, naturally, of the stimuli trying to reach it but there are some factors that will help or hinder this.

There are the endogenous factors, such as our personality and interest, our cardiac rhythm as well as psychological and physical state. And there are the exogenous ones, the environment, incentives, new events, drugs and/or tasks’ difficulty.

Now that’s a lot, isn’t it? As I said before, paying attention is hard.