Which biological factor may contribute to depression?

The biological factor that has been shown to contribute to depression is decreased left prefrontal cortex activity. This area of the brain is associated with positive emotions and mood regulation. When there is reduced activity in the left prefrontal cortex, individuals may have a harder time experiencing positive feelings and regulating their mood, leading to depressive symptoms. Research indicates that people with depression often exhibit lower levels of activation in this region compared to those without depression.

In contrast, increased activity in the right prefrontal cortex is often linked to negative emotional states and can be associated with depressive symptoms, making it less favorable in terms of mood regulation. Enhanced synaptic connectivity typically refers to improved communication between neurons, which is generally seen as beneficial for cognitive function and mental health. Lastly, stable hormone levels are unlikely to contribute to depression as fluctuations in hormones, particularly related to stress and mood regulation, are often implicated in mood disorders.