A major review of many studies looked at how a pattern of negative thinking—called the cognitive triad—affects depression. The triad includes having a negative view of yourself, the world around you, and your future. The review found a very strong connection between this thinking pattern and having more depressive symptoms.
Across all the studies, people who reported more negative thoughts also reported more depression. The link was strongest for negative views about oneself, but views about the world and future were also strongly connected. This was true in studies where people were checked at one point in time.
The review also looked at how these patterns might change over time. It found that having more depressive symptoms at the start predicted more negative thinking later on. For people aged 15 and older, having a negative triad also seemed to lead to more depression later. However, this pattern was not seen in younger kids under 15.
It is important to know that these findings show links, not proof that one causes the other. The evidence comes from a limited number of long-term studies. More research is needed to understand how these thoughts and feelings interact over time, especially in younger people.