4.1 The neurobiology of emotions

Panksepp argued that ‘an understanding of the neurobiology of raw affective experiences, from pain to joy, remain problems of foremost importance for understanding the evolution of human consciousness’ (Panksepp, 2005, p. 34), and that studying the emotional lives of animals is a necessary part of understanding human emotions.

Studying emotion in animals has a number of advantages, including the ability to examine emotions in a ‘raw’ state unaffected by human higher cognitive processes and sociocultural influences. It also allows researchers to conduct studies that would not be possible with human participants, including some basic neurological work exploring the brain structures involved in emotional processing. For example, the specific brain regions associated with different positive and negative emotions can be identified by direct electrical stimulation (e.g. Olds and Milner, 1954), which involves an invasive and potentially dangerous surgical procedure.

In such studies, the test subjects can be given control over the electrical stimulation of their own brains; for example, by pressing a lever to switch the electrical stimulation on or off. If the animal chooses to switch the stimulation on, that is considered to be evidence that the electrical stimulation produces a rewarding effect, indicating that the brain region where the electrode is located is involved in a positive emotion. The converse, of course, applies if the animal actively avoids stimulation, as that indicates that the brain area is involved in a negative, aversive emotion. This methodology, although originally developed in the 1950s, is still used to provide insight into the neural underpinnings of behaviour, particularly emotional motivational behaviour (e.g. Carlezon and Chartoff, 2007).