Treacher Collins syndrome

an autosomal dominant disorder that affects the development of small bones in the face. The facial anomalies—a small, retracted chin; small, downward-slanting eyes with defects of the iris; cleft palate; and deformed or absent external ears—vary from minimal to severe. Hearing loss may also occur. Most individuals with the syndrome have normal intelligence. Mutations in the TCOF1 gene are the most common cause of the syndrome. Also called Berry syndrome; Franceschetti–Zwahlen–Klein syndrome; mandibulofacial dysostosis. [Edward Treacher Collins (1862–1919), British ophthalmologist]

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Psychology term of the day

February 17th 2025

maze-bright and maze-dull rats

two groups of rats that were separated based on their performance in a standardized maze problem. Those that performed best were bred with each other, as were those that performed most poorly. Over relatively few generations, there was a complete separation in performance, with none of the maze-bright rats overlapping in scores with maze-dull rats. However, the selective breeding appeared to be specific to the maze tests that were used and did not affect learning ability more generally; moreover, maze-dull rats reared in an enriched environment (see enrichment) could perform as well as maze-bright rats.