^ Vodanovich, Stephen J. (November 2003) "Psychometric Measures of Boredom: A Review of the Literature" The Journal of Psychology. 137:6 p. 569 "Indeed, a shortcoming of the boredom literature is the absence of a coherent, universally accepted definition. The lack of an agreed-upon definition of boredom has limited the measurement of the construct and partly accounts for the existence of diverse approaches to assessing various subsets of boredom."
“Boredom – the psychological state that we experience whenever we are uninterested in what we are currently doing – is one of the defining traits of humanity. Time is the psychological nemesis of humankind. Tedium, a fundamental angst of humankind, arises from human beings’ ability to perceive time and our attempts to derive meaning from our personal existence.”
If he can maintain his concentration, Goetz intends to continue his own research into understanding the nature of boredom. He wants to measure physiological signs of arousal, which could one day add a new component to wearable health trackers. He’s also interested in investigating whether specific boredom types correspond to different age levels and cultures. “There are many important questions to be answered related to the boredom types,” he says.
Different scholars use different definitions of boredom, which complicates research.[9] Boredom has been defined by Cynthia D. Fisher in terms of its main central psychological processes: "an unpleasant, transient affective state in which the individual feels a pervasive lack of interest and difficulty concentrating on the current activity."[10] Mark Leary et al. describe boredom as "an affective experience associated with cognitive attentional processes."[11] In positive psychology, boredom is described as a response to a moderate challenge for which the subject has more than enough skill.[12][full citation needed]
The people who heard the barely noticeable TV rated themselves as more bored than either the ones who heard the loud TV or heard no soundtrack. The idea is that both the loud TV and the soft TV were distracting, but for those who heard the loud TV it was clear why they were distracted from the article. Thus, they may have been frustrated with the noise, but they were not bored. Those who heard the soft soundtrack had difficulty concentrating, but they were not sure why, and so they attributed the difficulty concentrating to boredom.
Lethargy is a state of tiredness, weariness, fatigue, or lack of energy. It can be accompanied by depression, decreased motivation, or apathy. Lethargy can be a normal response to boredom, inadequate sleep, overexertion, overworking, stress, lack of exercise, or a symptom of a disorder. When part of a normal response, lethargy often resolves with rest, adequate sleep, decreased stress, and good nutrition.[21][22]
Without stimulus or focus, the individual is confronted with nothingness, the meaninglessness of existence, and experiences existential anxiety. Heidegger states this idea as follows: "Profound boredom, drifting here and there in the abysses of our existence like a muffling fog, removes all things and men and oneself along with it into a remarkable indifference. This boredom reveals being as a whole."[27] Schopenhauer used the existence of boredom in an attempt to prove the vanity of human existence, stating, "...for if life, in the desire for which our essence and existence consists, possessed in itself a positive value and real content, there would be no such thing as boredom: mere existence would fulfil and satisfy us."[28]
These authors suggest that attention plays an important role in creating boredom. In particular, there are a few conditions that need to be met for people to feel bored. First, people need to have a reasonable level of psychological energy or arousal to feel bored. When people have low arousal and there is not much happening in the world, then they often feel relaxed. When they have high arousal, though, they have energy they would like to devote to something, but they cannot find anything engaging.
“I asked myself whether a life devoid of any affection, of any goal, a life one fills with a thousand trifles intended to relieve its monotony, populated with human beings one seeks out in order not to be alone and whom one flees to avoid being bored by them, whether such a life isn't ridiculous, whether anything whatsoever wouldn't be preferable.”

When the antiproton was discovered … it sent a wave of ennui through the physics community. Not that its discovery was unimportant, but on the basis of Dirac's theory, everybody expected it. — Roger G. Newton, The Truth of Science, 1997 Chauncey and I were keen enough about our aesthetic solution to the ennui of war to try to proselytize others. He organized discussion groups with the crew; I took volunteers to visit landmarks … — Louis Auchincloss, "Atlantic War," in Authors at Sea, ed. Robert Shenk,  1997 The attendant outside was standing on tennis balls, exercising the soles of her feet, her body swaying back and forth with the ennui of jelly. — Edna O'Brien, New Yorker, 17 June 1991 Thus the days of life are consumed, one by one, without an object beyond the present moment; ever flying from the ennui of that, yet carrying it with us … — Thomas Jefferson, in a letter dated 7 Feb. 1787 Thomas Jefferson: Writings,  1984 the kind of ennui that comes from having too much time on one's hands and too little will to find something productive to do