As we have seen already, the thyroid stands in very close relation to the ovaries, and, as we have often stated, the alteration of the ovaries is very apt to produce a swelling of the thyroid, as witnessed during menstruation, puberty, pregnancy, the puerperium, lactation, and the climacteric. Not only may the thyroid swell in many of these conditions, but the mental system is also changed during each of these processes. Sometimes it may be simple irritability, but at times the changes of the mind may develop into lunacy. Thus, in young girls, we occasionally see in the years of puberty mental changes, such as a tendency to wandering away from home, and even cases of lunacy, the so-called psychoses of puberty. Similar cases of insanity are equally frequent in pregnancy, and during the climacterium or after the experimental climacterium—castration. Again, insanity is not unfrequent in cases of degenerative disease of the ovaries; to such an extent, indeed, that sometimes a gynæcologist can treat a case of insanity in women better than a specialist in psychiatry. Not only in women, but in men changes in the sexual organ always produce far-reaching changes in the mind. Chronic gonorrhœa is the more to be feared on account of its invariably involving the prostate, the inflammation of which, in the same way as that of the testicles, is usually followed by symptoms of neurasthenia. If we now note this and remember that, according to Baldwin, in most cases of hysteria we may find at the autopsy alterations in the ovaries, we shall understand that the author of this book did not go too far when he stated, in a communication to the Belgian Congress of Neurologists, in Brussels, in 1906, that all cases of neurasthenia and hysteria are based upon pathological anatomical alterations, and that it is not true that, in contra-distinction to all other diseases, these should be the only ones without any pathological anatomical foundations. In fact, in nearly all cases of neurasthenia or hysteria we shall find changes in some of the ductless glands, particularly the thyroid, sexual, or pituitary body, if we only take the trouble to search for them. The degenerative alterations of the pituitary body are, as a rule, followed by the symptoms of the disease called acromegaly, and this also presents all the symptoms of a neurasthenic or hysteric condition. From the foregoing we shall understand why so many people, whether male or female—possibly the latter in greater number—who live in total sexual abstinence, present symptoms of neurasthenia or hysteria; for it has been shown by Rigaud and also by Mingazzini, that animals, living in total sexual abstinence, present alterations in the epithelia of the sexual glands (see Chapter XLVII).