The part of the human brain responsible for regulating temperature is the hypothalamus. This small but critical structure monitors body temperature and initiates responses to maintain homeostasis. When the body temperature rises, the hypothalamus signals mechanisms such as sweating and increased blood flow to the skin to cool the body. Alternatively, if the temperature drops, it triggers responses like shivering and reduced blood flow to retain heat. The hypothalamus integrates various signals, making it essential for thermoregulation and overall body balance.