Which neurobiological factor is associated with depression?

Low glucose metabolism is associated with depression because it reflects reduced energy availability in brain regions linked to mood regulation. Neuroimaging studies have consistently shown that individuals with depression often exhibit decreased glucose metabolism in certain areas of the brain, particularly in the prefrontal cortex and limbic systems. These areas are crucial for emotional processing, decision-making, and the regulation of mood. A lower metabolic activity indicates that these regions are less active, which can contribute to the symptoms of depression, such as low energy, difficulty concentrating, and a pervasive sense of hopelessness.

High glucose metabolism typically indicates increased activity in the brain, which interestingly may be observed in certain contexts or treatments but does not correlate with depressive states. Similarly, while increased blood flow in the anterior cingulate cortex has been noted in some studies related to emotional processing, it is not universally indicative of depression itself, as alterations can also signal other emotional or cognitive states. Finally, high serotonin levels are often associated with improved mood or the alleviation of depressive symptoms, making them an unlikely candidate for a neurobiological factor contributing to depression.