Depression, a weeks-to-years-long period of melancholy or hopelessness marked by symptoms such as weariness, sleep problems, a change in appetite, weeping fits, and even suicidal thoughts, can appear out of nowhere. Scientists would love to know the exact cause of depression, but research has so far only narrowed it down to hormonal changes induced by a variety of variables. These variables can be internal (genetics, hormonal swings, chronic pain, even gut flora) or external (childhood abuse, loss of a loved one, financial stress, or drug side effects), and they can all combine to make you feel like you'll never get out of bed again. Let's delve a little deeper into the details.
A Chemical Imbalance
Depression has long been studied. Hippocrates believed that an accumulation of black bile causes melancholia, the pre-medical term for depression. Since then, more precise scientific methods have discovered a chemical imbalance in the brain. Low levels of monoamine neurotransmitters, which help regulate mood, digestion, sleep, and other physiological functions, have been linked to depression for over 50 years. Doctors are unsure what causes these low levels, but they do know that antidepressant medications appear to raise them and effectively manage depression.
Family History of Depression
If members of your family have suffered from depression, you're more likely to get MDD (Major Depressive Disorder, commonly known as clinical depression). Depression is caused by a combination of genes. More than 800 families with recurrent depression were researched by a British study team, and a chromosome called 3p25-26 was identified as a possible genetic link. However, a recent British study looked at the links between 18 previously identified genes that were assumed to be candidates for hereditary depression and found none. Nonetheless, genes are likely to play a role, and many genetic variations are likely to be implicated.
Childhood Negative Experiences
Because their minds, as well as their confidence and self-esteem, are still developing, young children are particularly vulnerable to mistreatment and trauma. Although it can be, this trauma does not have to be shocking or violent. Physical, sexual, or emotional abuse, parental neglect, or growing up in a family with an alcoholic or drug addict can all leave long-term scars that are connected to depression. Even difficult events that don't qualify as "abuse," such as the death of a loved one or a tumultuous divorce, can lead to sadness. 75.6 percent of chronically depressive patients, according to study, have clinically significant histories of childhood trauma.
Anyone who has dealt with chronic stress and depression can attest to the fact that they are linked. Stressful life events, including (but not limited to) trauma, the death of a friend or family member, an ongoing bad relationship, constant pressure at work or school, caring for aging parents, and even media reports of terrorism, can activate the hypothalamic-pituitary-adrenal (HPA) axis, causing it to spit out extra cortisol. Chronic stress and chronically elevated cortisol levels have been linked to depression in studies.
Neuroplasticity modifications (how the brain alters its neural networks and synapses) produced by pain and depression have a lot in common. As a result, the two illnesses can exacerbate one other, creating a painful cycle of suffering and despair. Chronic pain, which is a form of stress, has been shown in studies to cause depression. On the other hand, studies show that up to 85% of patients with chronic pain are also depressed, which may seem high at first but isn't when you consider that pain and mood control share pathways. Consider it a yellow brick road that instead of leading to Oz, leads to Ow and Ugh. The insular cortex, prefrontal cortex, and anterior cingulate are some of the brain areas involved.