Because we live in a world of distraction, at any given moment, thousands of things might be competing for our attention, and our attention is pulled in so many different directions. In the classroom, there are many things to see and hear. We can focus on the teacher’s voice and the blackboard, although some distractors catch our attention for a few moments. During paying attention, the brain filters out the distractors and focuses on what really matters.
To direct attention is to choose, filter, and select: this is why cognitive scientists speak of selective attention. This form of attention amplifies the selected signal, but it also dramatically reduces those deemed irrelevant
What enables the brain to pay attention to a specific stimulus while being continuously bombarded with information?
American psychologist Michael Posner distinguishes at least three major attention systems in the brain:
1. Alerting, which indicates when to attend and adapts our level of vigilance.
2. Orienting, which signals what to attend to and amplifies any object of interest.
3. Executive attention, which decides how to process the attended information, selects the processes relevant to a given task and controls their execution.
These three systems form selective attention. In the space of a few minutes, your brain went through most of the critical states of attention: vigilance and alertness, selection and distraction, orientation, and filtering. In cognitive science, “attention” refers to all the mechanisms by which the brain selects information, amplifies it, channels it, and deepens its processing.
Selective attention operates in all sensory domains. In the vision, there are two ways to direct your attention; First, there’s overt attention. In overt attention, you move your eyes (saccades) towards something to pay attention to it. Second, there’s covert attention. In covert attention, you pay attention to something, but without moving your eyes (fixation). You continuously scan the surrounding area in covert attention, where you don’t actually look at them. For instance, this mechanism can be observed when we become aware of motion taking place in the peripheral areas of our vision while being focused on something else.
Our brain needs to do the overt and covert attention with specific reaction time and maintain them over time (sustain attention). This procedure happens with attentional networks in the three systems of Alerting, Orienting, and Executing.
The Alerting system is for awakening the brain. It sends warning signals that mobilize the entire body when circumstances require it. In the second system, the brain filters the stimuli from the millions of stimuli that bombard us. These two systems need to be controlled and should be in harmony with other cognitive processing. Here the third system, executive, works as the brain’s switchboard.
The neurons that encode the attended information increase their firing. The impact is twofold: attention makes the attended neurons more sensitive to the information that we consider relevant, but, above all, it increases their influence on the rest of the brain. Downstream neural circuits echo the stimulus to which we lend our eyes, ears, or mind. Ultimately, vast expanses of the cortex reorient to encode whatever information lies at the center of our attention. Attention acts as an amplifier and a selective filter.
Paying attention also involves choosing what to ignore. For an object to come into the spotlight, thousands of others must remain in the shadows. This is where the spotlight metaphor reaches its limits. To better light up a region of the cortex, our brain's attentional spotlight also reduces other areas' illumination. The mechanism relies on interfering waves of electrical activity: to suppress a brain area. The brain swamps it with slow waves in the alpha frequency band (between eight and twelve hertz), inhibiting a circuit by preventing it from developing coherent neural activity.
The brain actively suppresses specific signals to prevent avoid distractions. The researchers believe that our ability to focus on an object is only part of the attentional equation, while the other part is the anti-distraction system. The brain's filtering ability is a key for attention, which is missing in some people, for example, in people with Attention Deficit and Hyperactivity Disorder (ADHD). A person with ADHD cannot inhibit these distractors, and that’s why they can’t focus for a long time on a single task. ADHD is only one of the mental disorders struggling with attention and/ or inhibition problems. A vast range of them contains learning disorders, schizophrenia, anxiety, depression, and many other disorders.
We can see that paying attention is our brain's art, which is the first step of our further learning. Attention is different from learning, but it is essential for the brain entring the learning procedure. To enhance the brain’s cognitive function, assessing and rehabilitating the attention would be the first step.