Foundations

Emotions play a key role in our daily lives. Some people define them as the reactions that we as human beings experience as a response to events or situations, some describe them simply as a class of feelings, and others say they describe physiological states and are generated subconsciously. Psychologists describe emotions as “a complex state of feeling that results in physical and psychological changes that influence thought and behavior.” So, it appears that although we feel emotions, they are much harder to describe.

Our brains play a crucial role when creating and processing emotions. Historically, it was believed that each emotion was located in a specific part of the brain. However, research has shown that there is no single region of the brain that’s responsible for processing emotions – several brain regions are activated when emotions are being processed. Furthermore, different parts of the brain can generate the same emotion and different parts can also contribute to generating an emotion.

The reality may even be that emotion and sentiment are experiences that result from combined influences of biological, cognitive, and social aspects. Whatever the case, emotions matter because they help us decide what actions to do, how to negotiate tricky situations, and, at a basic level, how to survive. Different emotions rule our everyday lives; for example, we make decisions based on whether we are happy, angry, or sad, and we choose our daily pastimes and routines based on the emotions they facilitate. So, emotions are important, and understanding them may make our lives easier.

In this chapter, you will learn about the main concepts and differences between sentiment analysis and emotion analysis, and also understand why emotion analysis is important in the modern world. By combining this with a basic introduction to natural language processing (NLP) and machine learning, we will lay the foundations for successfully using these techniques for emotion analysis.

In this chapter, we’ll cover the following topics:

• Emotions
• Sentiment
• Why is emotion analysis important?
• Introduction to natural language processing
• Introduction to machine learning