The convolutions of the brain increase the surface area, or cortex, and allow more capacity for the neurons that store and process information. Each convolution contains two folds called gyri and a groove between folds called a sulcus. Certain folds and grooves perform specific brain functions, according to Mayfield Clinic. About 70 percent of the brain's 100 billion nerve cells are located in the cerebral cortex.
The cerebral cortex is responsible for functions such as language and information processing, according to Eric H. Chudler from the University of Washington. Specific areas of the cortex are involved with problem-solving and emotion; movement and coordination; voluntary movement; receiving information from the body; sensory association; processing visual input; detecting simple visual cues; language comprehension; processing auditory information; detecting sound quality; speech; and articulation.
Some large folds, called fissures, separate the four lobes located on each side of the brain, according to eMedicineHealth. The cerebrum is separated into two halves called the left and right hemispheres by a band of fibers called the corpus callosum. Speech, comprehension, arithmetic and writing are generally found only in the left cerebral hemisphere, while the right hemisphere controls creativity, spatial ability, artistic and musical skills. Most individuals have one dominant hemisphere, explains Mayfield Clinic.