DEMENSIYA, kamaqlii gayrimodarzodi,zafi ustuvori qobiliyati zehni va intellekt, ki bo kam shudani zakhirai donish, ikhtiloli khotira (hofiza) va muhokimaroni, kosta shudani takhayulot, az dast dodani malaka va g. padid meoyad. D. dar natijai bemorihoi gunogun, mas., falaji khurujyobanda, amrozi qishri magzi sar (bemorii Altsgeymer va Pik), sar, shizofreniya, osebi mayna, psikhozhoi pirsoli va g. paydo meshavad.