Optimal Level: The ideal level of arousal for an individual's peak performance. Too much or too little arousal can negatively affect performance.
Inverted U-shaped Curve: According to the Yerkes-Dodson law, there is an inverted U-shaped relationship between arousal levels and performance. Performance improves with increasing arousal up to a certain point, after which further increases in arousal can lead to diminishing returns or even decline in performance.
Stress: A state of mental or emotional strain resulting from demanding circumstances. High levels of stress can influence one's arousal levels and impact performance either positively or negatively depending on the situation.