The different theories of attention are the capacity theory, the mental bottleneck theory, and a few related theories of selective attention. Each of these theories uses models based on the ideas of the mental health researchers who first contributed to them. Psychologists who study attention theory attempt to determine the exact cognitive process of how people focus their attention on external stimuli. They also form and refine theories of attention concerning why certain people have longer versus shorter attention spans. The psychology of attention uses various relevant theories to find effective treatment options for people with noticeable attention problems.
Capacity theories of attention explain that people have a limited amount of attention to devote to any one thing at any given moment. A lot of competing information from different sources can cause their attention to reach its capacity rather quickly. When people's attention capacity hits its maximum limit, they generally experience a diminished ability to pay attention to any of the external information. Some psychologists who study these types of attention theories use them to point out the actual ineffectiveness of multitasking despite its prevalence in modern life. Multitasking and the frequent use of technology are additional contributing factors to some theories about attention.
A bottleneck attention theory dictates that everyone has a natural mental filter that will only allow certain amounts of information through at a time. This filter sorts what people first perceive as important based on an impression that lasts only a fraction of a second. Other stimuli that the brain designates irrelevant either does not pass through the filter or passes through only in pieces. Many psychologists study bottleneck theories of attention to determine why some people filter out certain kinds of information while others do not. This examination of the bottleneck attention theory often forms a basis for selective attention theories.
Theories about selective attention draw connections between peoples' varying attention levels and other related factors. Existing biases, interests, and past experiences can all influence how closely different people pay attention to a given topic. Psychologists can also draw conclusions about different people's innate abilities to give a subject their direct attention. Some theories of attention frequently help researchers determine the root causes of conditions such as attention deficit disorder. Many of these attention problems have underlying genetic causes, although some specific environmental factors can usually worsen or strengthen the ability to focus and concentrate.