The Neurobiology of Moral Sensitivity

According to psychologist Jonathan Haidt (2003), moral emotions differ from basic emotions (sadness, happiness, anger, fear, and surprise) in that they're intrinsically linked to the interests and well-being of society as a whole, as well that of each individual.

What’s the nature of morality? This debate has been the center of theorists’ arguments over decades. However, what about the neurobiology of moral sensitivity? Neurobiology, or neuroscience, is the scientific study of the nervous system. What have scientists discovered about where morals come from?

Currently, scientists consider certain skills, such as social sensitivity and cognition, to be central to the evolution of humanity. However, recently, new theories also emphasize the role of emotional and intuitive processes in the human decision-making process.

Research into neurobiology has been able to identify certain brain structures that are involved in producing basic emotions. However, the neural organization of more complex or secondary emotions (or moral emotions) is still unknown.

Certain fields of neuroscience have started to explore different types of moral emotions with neural imaging and electrophysiological techniques. In fact, one disciplinary field of study is affective neuroscience. Its goal is to classify emotions into basic mental operations and their corresponding neural mechanisms.

Thanks to research in these fields, emotions are defined as complex multi-factor phenomena that exercise a powerful influence over people’s behavior and thinking.

Moral emotions

According to psychologist Jonathan Haidt (2003), moral emotions differ from basic emotions (sadness, happiness, anger, fear, and surprise) in that they’re intrinsically linked to the interests and well-being of society as a whole, as well that of each individual.

With that in mind, you could say that moral emotions come into play during interactions between individuals. They can also affect a person when they perceive something as a moral violation.

Haidt also comments that basic emotions, on the one hand, come from ideas. They can also come from imagination, memories, or perceptions of immediate personal relevance. On the other hand, moral emotions are complex emotions. They’re closely linked to the well-being and interests of society, as well as that of people.

Circumstances that extend outside one’s personal sphere can also evoke moral emotions. They’re essential for the promotion of unity when people are working as a group.

Guilt, gratefulness, and compassion are some examples of pro-social moral emotions. However, negative moral emotions can also act against social interactions. Some examples of these emotions are contempt, xenophobia, or anger.

In his 2003 work, Haidt pointed out four main groups of moral emotions:

• Emotions relating to others (for example, contempt, anger, and dislike).
• Self-conscious emotions (for example, shame, embarrassment, and guilt).
• Emotions that relate to the suffering of others (for example, empathy).
• Emotions related to praising others (for example, gratefulness, fear, and admiration).

The neurobiology of moral sensitivity

Throughout the centuries, philosophical theories have adopted a logic and deduction-based approach to morality. Their objective has been to identify the universal principles that can guide human conduct.

Observable changes in the moral conduct of patients with cerebral problems have given researchers objective data about moral cognition. Thanks to that data, scientific discoveries about morality have helped us to better understand moral cognitive neuroscience.

In this context, investigators consider morality to be a collection of customs and values. Different cultural groups adopt these collections to guide their social conduct. Therefore, this perspective of morality doesn’t admit the existence of absolute moral values.

It may seem that the neural organization of complex or secondary emotions such as moral emotions is still unknown. According to published literature, it’s been proposed that moral phenomena come from the integration of the following areas of the brain:

• Contextual social knowledge (represented in the prefrontal cortex).
• Meaningful social knowledge (stored in the superior and posterior temporal lobes).
• Basic motivational states (depending on the circuits of the limbic cortex).

Neuronal basis of moral cognition

To determine the basis of moral cognition, researchers use studies conducted in patients with acquired brain damage. This way, they’ve discovered that certain areas of the brain are responsible for moral conduct.

Authors Eslinger and Damasio (1985) have conducted extensive research into the neurobiology of moral sensitivity. In their research, they described certain deficiencies in moral conduct in patients with brain damage. The patients they studied acquired this brain damage during adulthood, which occurred in certain areas of the prefrontal cortex.

Later, research showed that injuries in these areas of the prefrontal cortex that were acquired at an early age lead to damage or deterioration in some decision-making processes. This can occur both in behavior and in moral reasoning. Therefore, it seems that early injuries in the prefrontal cortex may affect moral development.

In addition to the prefrontal cortex, other regions of the brain also influence moral sensitivity and moral emotions. Certain structural changes in the anterior temporal lobe (both acquired and developing) can also impair moral behavior.

Neural circuit dysfunction involving the superior temporal sulcus (STS) region is a key area of the brain in social perception. It’s associated with difficulties in judgments of intentional action in people who suffer from autism, for example. This leads to a reduced feeling of pride and shame.

Moral and cognitive sensitivity has been fundamental in the evolution of human beings. The human brain contains a specialized network of neurons for moral processing that has yet to be fully investigated. It seems that much remains to be explored in the field of neurobiology and moral sensitivity.