whatever reason, this may increase his loneliness, resulting in him developing maladaptive cognition such as excessive neediness or suspicion of other friends. Hence leading to a further loss of human connection if he then goes on to split up with his remaining friends. Those other friends now become more lonely too, leading to a ripple effect of loneliness. Studies have however found that this contagion effect is not consistenta small increase in loneliness does not always cause the maladaptive cognition. Also, when someone loses a friend, they will sometimes form new friendships or deepen other existing relationships. Internet Studies have tended to find a moderate correlation between extensive internet use and loneliness, especially ones that draw on data from the 1990s, before internet use became widespread. Contradictory results have been found by studies investigating whether the association is simply a result of lonely people being more attracted to the internet, or if the internet can actually cause loneliness. The displacement hypothesis holds that some people chose to withdraw from real world social interactions so they can have more time for the internet. Excessive internet use can directly cause anxiety and depression, conditions which can contribute to lonelinessyet these factors may be offset by the internet's ability to facilitate interaction, and to empower people. Some studies found that internet use is a cause of loneliness, at least for some types of people. Others have found internet use can have a significant positive effect on reducing loneliness. The authors of meta studies and reviews from about 2015 and later have tended to argue that there is a bidirectional causal relationship between loneliness and internet use. Excessive use, especially if passive, can increase loneliness. While moderate use, especially by users who engage with others rather than just passively consume content, can increase social connection and reduce loneliness. Genetics In 2016, the first Genome-wide association study of loneliness found that the heredity of loneliness is about 14–27%. So while genes play a role in determining how much loneliness a person may feel, they are less of a factor than individual experiences and the environment. Previous smaller studies however, had estimated that loneliness may be between 37–55% hereditable. Other People making long driving commutes have reported dramatically higher feelings of loneliness (as well as other negative health impacts). Typology Two principal types of loneliness are social and emotional loneliness. This delineation was made in 1973