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three-mountains test

a Piagetian task used to assess visual perspective taking in children. A doll is placed at various locations around a three-dimensional display of three mountains, and children must indicate how the doll sees the display. Children younger than 8 years old have difficulty performing this test correctly, although they are able to understand that others have a visual perspective that is different from their own when less complicated tasks are used.

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Psychology term of the day

January 15th 2025

Laurence–Moon–Bardet–Biedl syndrome

Laurence–Moon–Bardet–Biedl syndrome

an autosomal recessive disorder first described in 1866 by British ophthalmologist John Zachariah Laurence (1830–1870) and his colleague, British-born U.S. ophthalmologist Robert C. Moon (1844–1914), in four siblings with progressive visual impairment, obesity, paralysis, and cognitive impairment. In 1920 and 1922, respectively, French physician George Bardet (1885–1970) and Romanian-born Austrian physician Artur Biedl (1869–1933) independently described patients sharing only some of the symptoms seen in the original siblings, plus additional symptoms that they did not exhibit (e.g., polydactyly, impaired speech, hypogonadism). The syndrome was thus divided into two related disorders, Laurence–Moon syndrome and Bardet–Biedl syndrome (BBS). However, because of overlapping phenotypes, it is thought to be one syndrome, with BBS being the term now commonly used to cover both syndromes. Also called Laurence–Moon–Biedl–Bardet syndrome.