American English takes a slightly different approach to the agreement of verbs with collective nouns. There is a very strong preference for the use of singular verbs with such nouns, so in American English you are much more likely to see, for example:
By Dr Ananya Mandal, MD. The human brain is divided into two hemispheres. The left hemisphere is the logical brain and is involved in language and analysis and the right hemisphere is the creative brain, involved in daydreaming and imagination. The left hemisphere controls the right side of the body while the right hemisphere controls the left side.
1 These upper portions of the brain are believed to be predominantly responsible. 2  for higher-order functions. 3  Divided into the left and right cerebral hemispheres. 4  Left cerebral hemisphere: In most people the left cerebral hemisphere is responsible for speech, math, reading, and writing.