" Many signs of depression are related to our cognitive abilities, like loss of concentration or a loss of memory (in the later stages). Once you start treating depression, some symptoms disappear but if the depression remains untreated, the symptoms can worsen and lead to a much faster cognitive decline, much earlier in the life course. There are observable changes in the brain structure and function for people with depression, and some of these changes can be temporary, but others cannot be reversed, which again is why it’s important to start treating depression at its earliest stages if you can. Our brains have enormous plasticity, so whatever we can do to help our brain return to normal, is positive. Physical exercise has been observed in animal models, and while these experiments are harder in humans, researchers saw positive reversible effects with animals with exercise. Ultimately, if you’re experiencing depression, it could have an effect on your cognitive abilities right now and expose you to a greater risk of getting dementia later on. But, if you intervene earlier on, you can lower your risk or return your brain to a healthier state. It’s never too late to care for your mental health and avoid these long-term negative outcomes. "