Importance
The ability to focus and sustain attention is important for staying on task amongst distractions and is fundamental to more complex processes such as memory and decision-making. Deficits in focusing and sustaining attention are quite common and in day-to-day life can manifest as lapses of attention while driving (such as missing your exit), not remembering a new acquaintance's name, or difficulty completing complex tasks. More serious deficits can lead to an increased propensity for accidents (i.e. car accidents or falls) and can make it difficult to maintain employment.

Attention and the brain
The optimal ability to sustain and focus attention occurs during a state of medium arousal (not too drowsy or too anxious) and when you are highly engaged by your current task. Sustained attention and focus also requires repeatedly disengaging from distractions and redirecting focus to back to the current task. Together, these processes have shown to rely on a broad network of brain regions that include the locus coeruleus in the brainstem as well as regions in the frontal and parietal lobes. The locus coeruleus makes norepinephrine, a neurotransmitter intimately involved in arousal, and supplies it to the entire brain. Frontal and parietal brain regions help to sustain attention and filter distractions and send feedback to the locus coeruleus. The back-and-forth between frontal and parietal brain regions and the locus coeruleus is a key to sustained attention and focus.

People with attention difficulties
Difficulty focusing and sustaining attention is prevalent in people with ADHD, age-related cognitive decline, traumatic brain injury, and post-traumatic stress disorder (PTSD). These deficits may be from damage to frontal and parietal lobe brain regions, too much or too little norepinephrine released from the locus coeruleus, or poor communication between the locus coeruleus and frontal and parietal brain regions. These deficits may be reflected in frequent lapses of attention in daily life, which may range from difficulty successfully accomplishing a complex task to falls (particularly in the aging population) to an increased risk of car accidents.

Past research
While there have been several drug and behavioral treatments aimed at improving focus and sustained attention, they have shown mixed results. For example, drug treatments (e.g. Adderall, Ritalin, Provigil) can be useful for treating alertness and sustained attention impairments, but the results are somewhat inconsistent and may cause unwanted side effects such as anxiety, headache, and nausea. A more benign and cost effective approach to improving alertness is focused attention meditation. Focused attention meditation involves attending to one object or sensation for a prolonged period of time. After several months of focused attention meditation, researchers have found improved sustained attention and increased attentional stability. Though these results are promising, for many individuals, focused attention meditation may be too boring or difficult without supervision.