For the next 20 years they showcased modern art with an emphasis on African-Americans, including work by abstract expressionist Norman Lewis, Boston-born Lois Mailou Jones (known for incorporating African images into her work) and lesser-known Washington-area artists.

FORBES: Magazine Article

People rely on their spatial knowledge to build many other more complex or abstract representations including time, number, musical pitch, kinship relations, morality and emotions.

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They also assessed their physical and neurological health, and carried out tests - including memory, language and abstract reasoning - to evaluate their condition.

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Chhau dance is a tradition from eastern India that enacts episodes from epics including the Mahabharata and Ramayana, local folklore and abstract themes.

UNESCO: Culture

Founded by Dr Anton Rupert, a tobacco billionaire, conservationist and critic of apartheid who was born in Graaff-Reinet in 1916, the museum is housed in a beautifully restored early 19th-century mission church, with mostly expressionistic and abstract canvases by South African artists, including Irma Stern and Maud Sumner.

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And it highlights the role of colour in the Russian abstract painters of the early part of the century, including a delightful harbour scene by the relatively unknown female artist Olga Rozanova.

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