SO GOOD QUOTES

St Maximus speaks very clearly to the issue:

The following four things are said to change the body’s temperament and through it to produce either impassioned or dispassionate thoughts in the intellect: angels, demons, the winds and diet. It is said that the angels change it by thought, demons by touch, the winds by varying, and diet by the quality of our food and drink and by whether we eat too much or too little. There are also changes brought about by means of memory, hearing and sight-namely when the soul is affected by joyful or distressing experiences as a result of one of these three means, and then changes the body’s temperament. Thus changed, this temperament in its turn induces corresponding thoughts in the intellect.

Mental Disorders & Spiritual Healing: Teachings from the Early Christian East
Jean-Claude Larchet