Mental workload (MWL) refers to brain activities, which are the number of resources in the human brain.

The 2-D Valence and Arousal Space (VA-Space) is the most usual dimensional emotion representation; valence shows how positive or negative an emotional state is, whilst arousal shows how passive or active it is.

Sentiment analysis is an aspect momentous for application in the future. Especially, emotional stress estimation helps improve our life.