The Neurobiology Of Moral Sensitivity

What is the nature of morality? This debate has been the focus of discussions of various theorists for decades. However, is there also a neurobiology of moral sensitivity?

At present, certain skills, such as social sensitivity and cognition, are considered central in the evolution of humanity. Recently, new proposals emphasize the role of emotional and intuitive processes in decision-making in human beings (1).

Research in neurobiology has managed to identify some brain mechanisms and structures that are involved in basic emotions. However, the neural organization of complex or secondary emotions as “moral” emotions is still unknown (1).

The field of affective neurosciences has begun to explore different types of moral emotions with neuroimaging and electrophysiological techniques. In fact, a new discipline is emerging called affective neuroscience . The objective of this is to subdivide the emotions into elementary mental operations and their corresponding neural substrates.

Thus, emotions are defined as complex multifactorial phenomena that exert a powerful influence on people’s behavior and enable their adaptation to the environment (2).

Moral emotions

According to the psychologist Jonathan Haidt (2003), moral emotions differ from basic emotions (sadness, joy, anger, fear, surprise) in that they are intrinsically linked to the welfare interests of each society, as well as individuals.

Thus, it could be said that moral emotions arise from the interaction between individuals or when moral violations are perceived. Furthermore, Haidt points out that, on the one hand, basic emotions come from ideas. They also come from imagination, recollection, or perception with immediate personal relevance. On the other hand, moral emotions are complex emotions  that are linked to the interests or well-being of societies, as well as people.

Furthermore, moral emotions are evoked in circumstances that extend beyond one’s immediate sphere. They are critical to promoting group cohesion.

Guilt, gratitude, and compassion are examples of pro-social moral emotions. However, moral emotions can also act in social dissolution and reorganization. These types of emotions can be contempt, xenophobia or outrage.

Thus, Haidt (2003) points out four subtypes of moral emotions :

• Emotions concerning others (eg, contempt, anger, disgust).
• Self-aware (eg, shame, embarrassment, guilt).
• Emotions related to the suffering of others (for example: empathy).
• Regarding the praise of others (for example: gratitude, fear, elevation).

The neurobiology of moral sensitivity

Through the centuries, philosophical theories have adopted a logical-deductive approach to morality whose objective has been to identify the universal principles that can guide human behavior (1).

The changes seen in moral behavior in patients with brain dysfunction have provided objective data about moral cognition. That is why a scientific approach to morality appears: moral cognitive neuroscience.

In this context, morality is considered as a set of customs and values. This set is adopted by a cultural group to guide social behavior. Thus, this view does not assume the existence of absolute moral values ​​(1).

It seems that the neural organization of complex or secondary emotions such as moral emotions is still unknown. According to the literature, it has been postulated that moral phenomena emerge from the integration of :

• The contextual social knowledge (represented in the prefrontal cortex)
• The social semantic knowledge (stored in the posterior and anterior temporal cortex), and
• The basic motivational states (dependent on cortico-limbic circuits).

Neural bases of moral cognition

To determine the basis of moral cognition, researchers use studies conducted in patients with acquired damage. Thus, it is known that certain brain regions can be crucial for moral behavior.

Authors Eslinger and Damasio (1985) are known for investigating the neurobiology of moral sensitivity. Thus, they described certain deficiencies in moral behavior in patients with damage acquired during adulthood in the ventromedial prefrontal cortex.

Later it was shown that lesions in the ventromedial prefrontal cortex acquired at an early age lead to damage or deterioration. This can occur both in behavior and in moral reasoning. Thus, it appears that moral development may be affected by early lesions in the prefrontal cortex (1).

In addition to the prefrontal cortex, there are other brain regions involved in the neurobiology of moral sensitivity. Certain structural changes in the anterior temporal lobe (both acquired and developmental) can also impair moral behavior.

Neural circuit dysfunction involving the superior temporal sulcus (STS) region is a key area for social perception. Thus, it is associated with the difficulty in attributing intentionality experienced by those who suffer from autism. This leads to the reduced experience of pride and shame.

Moral and cognitive sensitivity has been fundamental in the evolution of the human being. The human brain carries within it a specialized network for moral processing that has yet to be fully discovered. Thus, it seems that much remains to be explored in the field of the neurobiology of moral sensitivity.