In a learning environment, a common cause of boredom is lack of understanding; for instance, if one is not following or connecting to the material in a class or lecture, it will usually seem boring. However, the opposite can also be true; something that is too easily understood, simple or transparent, can also be boring. Boredom is often inversely related to learning, and in school it may be a sign that a student is not challenged enough, or too challenged. An activity that is predictable to the students is likely to bore them.[31]
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]
Second, boredom typically occurs when people have trouble focusing their attention and they believe the reason for this difficulty is in the environment. When sitting in the airport, for example, there is probably a lot going on. There are people having conversations that you could listen to. You probably have something to read. There may be televisions showing the news. But, the stress of waiting for a delayed flight often makes it hard to concentrate, and so your mind jumps from one thing to another. You assume that this is caused by the environment, and so you feel boredom.
“Boredom is a flight from what is important. Like workaholism and perfectionism, it is a way of distracting yourself from inner experiences. It occurs when you look outward and do not find anything to engage your attention. Instead of feeling your emotions - becoming aware of the functioning of your energy system - you become bored. Boredom ... is a flight from your higher potential. It is fear of the transformation that wants to occur, and will occur in you, when you explore your emotions. It is your resistance to spiritual growth.”
The highest levels of arousal and negative emotions. A person in a reactant boredom state has a strong motivation to escape his or her boring situation and avoid those responsible for it (such as teachers or a boss). Reflects significant restlessness and aggression. There are persistent thoughts about specific, “more highly valued alternative situations.”
“To me, at least in retrospect, the really interesting question is why dullness proves to be such a powerful impediment to attention. Why we recoil from the dull. Maybe it’s because dullness is intrinsically painful; maybe that’s where phrases like ‘deadly dull’ or ‘excruciatingly dull’ come from. But there might be more to it. Maybe dullness is associated with psychic pain because something that’s dull or opaque fails to provide enough stimulation to distract people from some other, deeper type of pain that is always there, if only in an ambient, low-level way, and which most of us spend nearly all our time and energy trying to distract ourselves from feeling, or at least from feeling directly or with our full attention. Admittedly, the whole thing’s pretty confusing, and hard to talk about abstractly…but surely something must lie behind not just Muzak in dull or tedious places any more but now also actual TV in waiting rooms, supermarkets’ checkouts, airport gates, SUVs’ backseats. Walkman, iPods, BlackBerries, cell phones that attach to your head. This terror of silence with nothing diverting to do. I can’t think anyone really believes that today’s so-called ‘information society’ is just about information. Everyone knows it’s about something else, way down.”
One more key element of boredom is control. Boredom often occurs when you have little control over your situation. Waiting rooms, lectures, and airline gates are all places where you have little control over your situation. Normally, we react to unpleasant situations by changing the situation. If you don’t like a book you are reading, for example, you close it and do something else. Boredom happens when you are unable to change the situation.  
There are three types of boredom, all of which involve problems of engagement of attention. These include times when we are prevented from engaging in wanted activity, when we are forced to engage in unwanted activity, or when we are simply unable for some other reason to maintain engagement in an activity.[13] Boredom proneness is a tendency to experience boredom of all types. This is typically assessed by the Boredom Proneness Scale.[14] Recent research has found that boredom proneness is clearly and consistently associated with failures of attention.[15] Boredom and its proneness are both theoretically and empirically linked to depression and similar symptoms.[16][17][18] Nonetheless, boredom proneness has been found to be as strongly correlated with attentional lapses as with depression.[16] Although boredom is often viewed as a trivial and mild irritant, proneness to boredom has been linked to a very diverse range of possible psychological, physical, educational, and social problems.[19]

Although it has not been widely studied, research on boredom suggests that boredom is a major factor impacting diverse areas of a person's life. People ranked low on a boredom-proneness scale were found to have better performance in a wide variety of aspects of their lives, including career, education, and autonomy.[30] Boredom can be a symptom of clinical depression. Boredom can be a form of learned helplessness, a phenomenon closely related to depression. Some philosophies of parenting propose that if children are raised in an environment devoid of stimuli, and are not allowed or encouraged to interact with their environment, they will fail to develop the mental capacities to do so.
Then, after a baseline EEG test measuring normal brain activity, the researchers assigned the participants a tedious task: they had to turn eight virtual pegs on a screen as the computer highlighted them. This activity lasted approximately 10 minutes, during which time the researchers used EEG caps to measure participants’ brain activity as they carried out the boring task.
Boredom is similar to mental fatigue and is caused by repetition and lack of interest in the details of our tasks (such as tasks that require continuous attention, waiting at the airport, prisoners locked in cells). Any experience that is predictable and repetitive becomes boring. In general, too much of the same thing and too little stimulation can cause in its victim an absence of desire and a feeling of entrapment (Toohey, 2012).    
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