What Causes Directed Attention Fatigue?
Directed Attention is so basic to thinking and functioning that you may not notice you are using it. But it is very easy to wear out attention, and since Directed Attention Fatigue (DAF) can be a problem, it is helpful to know what causes it, so you can plan when to stop, or schedule specific restorative activities.

A. Activities that can lead to DAF
• Concentrating too hard or too long on tasks like taxes or homework, or trying to understand unfamiliar concepts.

• Fending off distractions or preserving signal in the face of noise, such as studying with the TV on, or trying to follow a conversation in a noisy room.

• Running multiple models, such as deception, secrets, trying to be polite, or talking while worried about something else can drain attention fast. You also run multiple models when you compare different plans or ideas, or do creative work.

B. Environments and situations that can lead to DAF
• Staying safe in dangerous environments is particularly fatiguing--trying to live and work while avoiding danger just adds to the drain.

• Incompatible environments that do not suit what you are trying to do are fatiguing. A library is incompatible with practicing opera singing, a busy street is incompatible with a quiet private conversation. Confusing environments are also draining.

• Being a caregiver for someone ill is notoriously fatiguing. So are social situations if you are shy, dealing with stereotypes, trying to impress someone, or if there are culture differences.

• Work-related situations that are dangerous or demand extra vigilance are obviously draining. So are working long hours, doing presentations, attending conventions, being in graduate school, or working in a company that is in trouble or being downsized.

• One-time fatiguing events include a death in the family, taking tests, or dealing with emergencies. In some emergencies, Fascination takes over, but that’s another story for later.

C. Habits that can lead to DAF
• Cultures may promote a hyperactive work ethic, consider healthful sleep and restorative activities slothful, or encourage draining secrets and elaborate social structures.

• Cognitive habits such as trying to do or remember too much, not taking breaks, multitasking, and making excessive demands on yourself or the world can drain attention.

D. Physiological circumstances that can lead to DAF
• Lack of sleep is the biggest cause of Directed Attention Fatigue, and the best thing you can do is to get more sleep.

• Illness or injury can directly interrupt the brain circuits which drive attention. Being sick brings many fatiguing worries and concerns, and dealing with pain is a huge attention drain.

• Directed Attention varies with age and individual differences.

The system grows rapidly before age 5, but can take two decades to really mature and function well. Individuals differ greatly in how much Directed Attention is available and when it comes online.

Some of us never have much Directed Attention available, and must rely on built-in fascination and avoid fatiguing activities. Others develop good attention, but more slowly, and may not be able to focus and fend off distractions until late grade school. Then, just when you have gotten good at it, attention begins to decline with advancing age.

References
Kaplan, S. (1978). Attention and fascination: The search for cognitive clarity. In S.
Kaplan & R. Kaplan (Eds.), Humanscape: Environments for people. Belmont, CA: Duxbury. (Republished by Ann Arbor, MI: Ulrich's, 1982)

Kuo FE, Sullivan WC. Aggression and violence in the inner city: impacts of environment via mental fatigue. Environment Behav. 2001;33:543–571.

Michael I. Posner and Jin Fan, Attention as an Organ System, Sackler Institute, Weill Medical College of Cornell University. This paper was presented at the De Lange Conference, March 2001