One factor that is becoming increasingly appreciated in modern psychology is that inner states depend on the chemistry of the body. Many hormones, enzymes, and neurotransmitters are found to be central in regulating emotions, moods, and internal mental states. When the body sufferers from some kind of biochemical imbalance, one's inner state becomes disturbed. As a result, it has been found that many difficult inner conditions, such as some types of depression, anxiety and phobias, some forms of schizophrenia, etc., are due to such chemical imbalances, and that some pharmaceutical drugs can help alleviate these conditions by redressing the imbalance. It seems that the soul is not able to experience and develop all of her potential when such limitations are present. For example, it is not easy for the soul to feel light and optimistic when it is suffering from a chemical depression, regardless how much inner work she does. The manifestation of some of the soul’s potential inner states and capacities requires the chemistry of the body to be healthily functioning. This physical limitation can become a limitation in the experience of some essential aspects, even essence in general.