In acute pain, an injury sends a pain signal from the tissue to the back part of the spinal cord, where the signal crosses to the other side of the spinal cord and travels up long nerve tracks to the brain. Here it goes to 16 different areas. Pain is only perceived when it reaches the upper part of the brain (Amydala, Insula, Prefrontal Cortex, Anterior Cingulate Cortex, Posterior Cingulate Cortex, Posterior Parietal Cortex, Secondary Somatosensory Cortex, Primary Somatosensory Cortex and Supplementary Motor Area). Acute pain tells us when we have exceeded a physical and/or emotional limit, directing us to stop doing whatever is causing this problem. Once that problem is addressed, the brain sends a signal to the back part of the spinal cord and intercepts and stops the incoming pain from the injury.