Home > Conscious > Chapter 10 > 10.1. Descartes' Pineal Gland Hypothesis


In the article, "Descartes' dogma and damage to Western psychiatry (Ventriglio and Bhugra, 2015), the President of World Psychiatric Association (Dinesh Bhugra) and his colleague stated that

"René Descartes described the concept of mind-body dualism in the 16th century..... We believe that his dogma has caused tremendous amount of damage to Western psychiatry. This dualism has created boundaries between mind and body but as we know they are inextricably interlinked and influence each other."

To my knowledge, Descartes never said that mind and body could not influence each other. In fact, Descartes explicitly postulated that the mind and body could interact through the pineal gland - a small endocrine gland near the center of the brain (Figure 10-1). According to his hypothesis, the mind may cause movement of the pineal gland, which in turn changes the tension of muscles, thereby resulting in bodily movement (Stanford Encyclopedia of Philosophy).


Figure 10-1. Diagram for the mind-body interaction proposed by Descartes. [Source: Wikipedia]

Although modern neuroscience did not find any motor system connected to the pineal gland, Descartes' basic idea could be right: the mind may act on a particular brain area to trigger movement. This area can now be identified as the striatum which plays a central role in action selection: Go or NoGo.

In this book, the mind is defined as the immaterial part of an animal. While being "immaterial", the mind is still made up of physical entities. Based on modern physics, electromagnetic (EM) and gravitational (GR) waves are the only physical entities that do not belong to matter or material. Both EM and GR waves can be generated simultaneously by the accelerated motion of ions as they pass through ion channels during neuronal activation. The GR waves have strong mutual attractive force which is well suited for the conscious perception of the mind (Chapter 8), but interact extremely weakly with matter. They cannot influence neuronal processes. In contrast, the EM-EM attraction is negligible but the EM-matter interaction is many orders of magnitude stronger than the GR-matter interaction. Therefore, the mind-body interaction should be mediated by the EM waves.

The feeling of pleasure or pain is a mental state. The interaction between EM waves and the striatum may lead to the pleasure principle: "seek pleasure, avoid pain". Its underlying physical mechanism will be briefly described in Section 10.4. Further details are presented in Chapter 13.