Why do people stop concentrating after a long period of time?
There could be a number of reasons. You might be distracted by alternative stimuli. Or you could simply be bored or uninspired by the material you have to attend to. One of the outstanding features of the brain is that it doesn't like to be bored! If you're bored by something, then you try and stimulate your brain. One of the theories about AD/HD is that children who are very hyperactive are trying to stimulate themselves because they are bored. That is one reason why they're prescribed Ritalin, which is a stimulant. A stimulant artificially increases the level of arousal of the brain, so the child doesn't have to engage in behavioural strategies to try and overcome his boredom.
Finally, your brain sets limits on what it can take in within a period of time. After about 20-30 minutes, the brain says, “Enough, let me process what I have been given so far, don't give me anymore until I process what I have”. This is why, when you are studying for an exam, it is best to take 10 minute breaks every 30-45 minutes or so, to let your brain assimilate what you have studied to that point, without trying to force more information in.
- Ridha Joober, MD, PhD and Natalie Grizenko, MD, 2008
Can someone develop ADHD or attention problems because of an inadequate environment, parental negligence, or understimulation during childhood?
Children react in a behavioural way, notably through hyperactivity or impulsiveness. Sometimes, these behaviours can be a reaction to a very difficult situation. Child abuse and negligence, for example, can be associated with attention deficits. Attention is very fragile during development. Genetic factors can also play a role. It has also been shown that any early brain trauma can impair attention. In fact, extremely premature babies will often have attention difficulties, as this function is very fragile and can easily can be disrupted by environmental factors.
-Ridha Joober, MD, PhD, Mini-Psych School 2010
Has TV and/or video games led to an increase in ADHD?
There are studies that indeed show a relationship between attention deficit hyperactivity and extended TV watching, along with a higher risk of being overweight. Often parents say that their child is capable of concentrating on TV. The problem is not being able to concentrate on TV; it’s that sitting there, just like playing computer games, is a passive activity. ADHD appears or manifests when people have to put effort into an activity. The effort is what is very painful for people with ADHD.
-Ridha Joober, MD, PhD, Mini-Psych School 2010