Dr. Altschuler loves nothing more than a knotty theoretical issue in his field. He also enjoys crossword puzzles, brain teasers, and the like. Dr. Altschuler has a high need for ?

Cognition

Explanation:

Cognition is defined as the mechanism in which perception and knowledge about something is obtained through sense and mental processes. This learning gives a person understanding and information that makes them aware and states how a person thinks.

According to the question, high requirement of condition is required by Dr. Altschuler as he is interested in crosswords, puzzles, and other brain related issues. Thus, he includes mind thinking processes and perception of things for understanding and solving questions.  

mali had been a state inside of the ghanaian empire. after ghana fell because of invading forces and internal disputes, mali rose to greatness under the leadership of a legendary king named sundiata, the "lion king." the songhai empire, already weakened by internal political struggles, went into decline.