In addition to estrogen and GH/IGF-1 both being essential for pubertal breast development, they are synergistic in bringing it about.Despite the apparent necessity of GH/IGF-1 signaling in pubertal breast development however, women with Laron syndrome, in whom the growth hormone receptor (GHR) is defective and insensitive to GH and serum IGF-1 levels are very low, puberty, including breast development, is delayed, although full sexual maturity is always eventually reached. Moreover, breast development and size are normal (albeit delayed) in spite of GH/IGF-1 axis insufficiency, and in some the breasts may actually be large in relation to body size. The relatively large breasts in women with Laron syndrome have been suggested to be due to increased secretion of prolactin (which is known to produce breast enlargement) caused by a drift phenomenon from somatomammotrophic cells in the pituitary gland with a high GH secretion. An animal model of Laron syndrome, the GHR knockout mouse, shows severely impaired ductal outgrowth at 11 weeks of age. However, by 15 weeks, ductal development has caught up with that of normal mice and the ducts have fully distributed throughout the mammary fat pad, although the ducts remain narrower than those of wild-type mice. In any case, female GHR knockout mice can lactate normally. As such, it has been said that the phenotypes of women with Laron syndrome and GHR knockout mice are identical, with diminished body size and delayed sexual maturation accompanied by normal lactation.
: 174 The related schizotypal personality disorder and schizophrenia are reported to have ties to creative thinking, and it is speculated that the internal fantasy aspect of SzPD may also be reflective of this thinking. Alternatively, there has been an especially large contribution of people with schizoid symptoms to science and theoretical areas of knowledge, including maths, physics, economics, etc. At the same time, people with SzPD are helpless at many practical activities because of their symptoms. Secret schizoids
Many schizoid individuals display an engaging, interactive personality, contradicting the observable characteristic emphasized by the DSM-5 and ICD-10 definitions of the schizoid personality. Guntrip (using ideas of Klein, Fairbairn and Winnicott) classifies these individuals as "secret schizoids", who behave with socially available, interested, engaged and involved interaction yet remain emotionally withdrawn and sequestered within the safety of the internal world. : 17  Klein distinguishes between a "classic" SzPD and a "secret" SzPD, which occur "just as often" as each other. Klein cautions one should not misidentify the schizoid person as a result of the patients defensive, compensatory interaction with the external world. He suggests one ask the person what their subjective experience is, to detect the presence of the schizoid refusal of emotional intimacy and preference for objective fact.Frequently, a schizoid individuals social functioning improves, sometimes dramatically, when the individual knows they are an anonymous participant in a real-time conversation or correspondence, e.g. in an online chatroom or message board. It is often the case the individuals online correspondent will report nothing amiss in the individuals engagement and affect.