# Heart, Brain & Emotions See how the brain and heart talk through nerves, and how anger, fear, sadness, calm, love and joy each change the heartbeat in colour\. By brave\-badger\-013535f8 Topic: Human Body & Medicine [Open the interactive Jig](https://ask.jig.com/j/sIUByLpoCue3) ## Transcript ### 1. Two organs, one conversation Your brain and your heart talk all day long\. Every feeling you have changes how your heart beats, and your heart sends news back up\. Let’s watch the conversation\. Turn the glass figure by dragging anywhere around it\. ### 2. The heart’s own drummer Your heart is a fist\-sized muscle that squeezes about 100,000 times a day\. A tiny spark\-maker called the pacemaker \(the white flash at the top\) starts every beat\. The brain never starts a beat; it only speeds the drummer up or slows it down\. Each beat pushes out about 70 millilitres of blood: roughly a small cup\. ### 3. Feelings begin in the brain Emotions are made in the brain\. The amygdala, an almond\-shaped alarm deep inside, notices what matters\. The hypothalamus, a control centre just above the brainstem, turns that into orders for the body\. You have two amygdalae, one on each side of the brain\. ### 4. The accelerator Orange sparks run down the spinal cord and along nerves to the heart\. They release noradrenaline, a chemical messenger that makes the heart beat faster and harder\. Press Surprise\! to feel the rush\. Adrenaline from glands above the kidneys joins in through the blood\. ### 5. The brake The vagus nerve is the brake\. Its teal signals travel from the brainstem down the neck and slow the heart\. A long, slow breath out presses this brake a little\. Vagus means “wandering” in Latin: this nerve wanders from the brain to the heart, lungs and belly\. ### 6. A colour for every feeling Tap an orb\. Red is anger, violet fear, blue sadness, teal calm, pink love and gold joy\. Watch the heart’s speed, squeeze and rhythm change, and see which signals light up\. Heart rates shown are typical examples\. Every person’s heart responds a little differently\. ### 7. The heart talks back Most vagus nerve fibres carry messages up, from the body to the brain\. Pressure sensors in big blood vessels report every beat, shown as golden sparks rising\. The brain uses this news to shape how we feel\. About four out of five vagus nerve fibres are sensory: they listen rather than command\. ### 8. The rhythm of calm A healthy heart does not tick like a clock\. When you are calm, the gap between beats stretches and shrinks with each breath: this is heart rate variability\. Fear and stress make the rhythm stiffer; calm keeps it flexible\. Watch the monitor: in calm, the beats speed up a little as you breathe in and slow as you breathe out\.