Connection between body and mind is there all the time. In fact, according to the Yoga philosophy, first there is mind, then there is body. First comes thought and that thought has influence on the body. The mind comprises all the things that we desire and all the things we dislike; all our fears about not having enough and not being able to fulfil our desires. This is constantly at work even when we are asleep, through our dreams. The mind is its own entity and we cannot perceive how much influence it has on us.
First let us look into what the mind actually is and what effect the mind has on the body. Over fifty years ago Western society realised that all the malfunctions of the body were indeed related to the mind. This wisdom existed long ago but was popularised by Western philosophers or psychologists. The refusal of this fact is largely based on the desire to sell pharmaceuticals. If the mind is pacified and taken away from its wrong movements it no longer requires medical intervention. Anyone who meditates knows that thoughts produce certain sensations in the body. This is the basis of Vipassana meditation. Most of the time we are unable to watch our sensations because we are over stimulated. When we meditate we are able to see the rise of certain thought patterns and all the sensations that go with it. Other teachers such as BKS Iyengar, Ekhart Tolle and Krishnamurti - all supported these views in their work. The author Louise Hay cured herself of cancer by exploring how thought patterns affect physical health and which specific thought patterns create specific illnesses. This whole knowledge is what Yoga is about; the understanding that as long as the mind is the peace is not.