via different mechanisms and is not generalizable to the broader underlying neurotypes. Proponents of the hypothesis claim people with schizotypal personality have an enhanced theory of mind, increased emphatic ability, and an improved ability to recognize the emotions of others, but this is not supported by research on the schizotypal personality disorder population or on measures of 'healthy' schizotypy in the general population. Rather, theory of mind appears to be impaired in all schizophrenia-spectrum conditions even in the absence of frank psychosis. Factors such as nutrition during pregnancy are believed to affect imprinting. Proponents note that schizophrenia is associated with maternal starvation during pregnancy while autism has increased in diagnostic prevalence in affluent societies, although the general scientific consensus is that rising rates of autism diagnosis in wealthy societies are related to awareness rather than prevalence. Autism and schizophrenia appear to be related to birth weight in opposite ways, with autism being associated with high birth weight and schizophrenia with low birth weight. Supporters of the hypothesis point towards this association as evidence. Proponents of the hypothesis also point towards genetic disorders with an elevated risk of one disorder and not the other, especially imprinting disorders, to support their claims. For instance, Beckwith-Wiedemann syndrome is caused by increased effects of paternally imprinted genes and has an increased incidence of autism. Contrary to the overall claim here, the majority of disorders that raise the risk of one of autism and schizophrenia also do so for the other, including in ways that directly contradict the imprinted brain hypothesis such as for imprinting disorders. For instance, velocardiofacial syndrome is associated with significant increases (10- to 40-fold above the general population) in the risk for both autism and schizophrenia. Data from copy number variation and genome-wide association studies support shared genetic mechanisms causing schizophrenia and autism, although this only lends circumstantial support to the imprinted brain hypothesis and can also be used to support many competing hypotheses. The role of oxytocin in autism and schizophrenia has also been researched, and some findings and characterizations of the research have been used in favour of the hypothesis. Oxytocin appears to have treatment potential in both autism and schizophrenia, likely including schizotypal personality disorder. Crespi proposes that, contrary to this suggestion, high oxytocin is a contributing factor in population schizotypy and creates "hyper-developed" social understanding that induces psychosis. Supporters of the hypothesis point towards associations between higher