The mind can impact how the body responds, because at the end of the day, your mind is part of your body. Your mind is a function of your brain and your brain is part of the Central Nervous System of your body - so it is no surprise that your brain can and does affect your body.
We know that mental stress impairs the immune system, due to the release of corticosteroids and other hormones. We know that your emotional state has an effect on your heart rate, due to parasympathetic and sympathetic nerve innervation of the heart - this is why "Broken Heart Syndrome" is a real thing: people who have suffered extremely emotional stress develop myocardial stunning, which can damage the heart (albeit not very much - Troponin I levels are detectable, but it's low).
There is no "mind over matter". The mind IS matter - in the form of nerves, neurons, ganglia, astrocytes (supporting cells in the brain), and so on and so forth. In the olden days, people thought there was a "duality" - mind and body being separate. Modern neuroscience teaches us that, no, at the end of the day, mind is matter and your body and mind are part of the same system.
We know that mental stress impairs the immune system, due to the release of corticosteroids and other hormones. We know that your emotional state has an effect on your heart rate, due to parasympathetic and sympathetic nerve innervation of the heart - this is why "Broken Heart Syndrome" is a real thing: people who have suffered extremely emotional stress develop myocardial stunning, which can damage the heart (albeit not very much - Troponin I levels are detectable, but it's low).
There is no "mind over matter". The mind IS matter - in the form of nerves, neurons, ganglia, astrocytes (supporting cells in the brain), and so on and so forth. In the olden days, people thought there was a "duality" - mind and body being separate. Modern neuroscience teaches us that, no, at the end of the day, mind is matter and your body and mind are part of the same system.