(see thrombosis). also, in releasing the valsalva maneuver blood pressure falls; this, coupled with standing up quickly to leave the toilet, can result in a blackout. a person defacating outside. etching, paper. jacques callot. rijksmuseum, amsterdam. 1621 society and culture open defecation main article: open defecation open defecation is the human practice of defecating outside (in the open environment) rather than into a toilet. people may choose fields, bushes, forests, ditches, streets, canals or other open space for defecation. they do so because either they do not have a toilet readily accessible or due to traditional cultural practices. the practice is common where sanitation infrastructure and services are not available. even if toilets are available, behavior change efforts may still be needed to promote the use of toilets. open defecation can pollute the environment and cause health problems. high levels of open defecation are linked to high child mortality, poor nutrition, poverty, and large disparities between rich and poor.: 11 ending open defecation is an indicator being used to measure progress towards the sustainable development goal number 6. extreme poverty and lack of sanitation are statistically linked. therefore, eliminating open defecation is thought to be an important part of the effort to eliminate poverty. anal cleansing after defecation main article: anal hygiene the anus and buttocks may be cleansed after defecation with toilet paper, similar paper products, or other absorbent material. in many cultures, such as hindu and muslim, water is used for anal cleansing after defecation, either in addition to using toilet paper or exclusively. when water is used for anal cleansing after defecation, toilet paper may be used for drying the area afterwards. some doctors and people who work in the science and hygiene fields have stated that switching to using a bidet as a form of anal cleansing after defecation is both more hygienic and more environmentally friendly. mythology and tradition the caganer is a defecating figurine in spanish nativity scenes some peoples have culturally significant stories in which defecation plays a role. for example: in an alune and wemale legend from the island of seram, maluku province, indonesia, the mythical girl hainuwele defecates valuable objects. one of the traditions of catalonia (spain) relates to the caganer, a figurine depicting the act of defecation which appears in nativity scenes in catalonia and neighbouring areas with catalan culture. the exact origin of the caganer is lost, but the tradition has existed since at least the 18th century. psychology some aspects of psychology surround the act of defecation. there is an inherent desire for privacy among humans. freud stipulated a second stage of development, the anal stage, which centers around the release of waste from the bladder and bowels. he categorized two types: anal retentive and anal expulsive.