Central sulcus
The evolution of the central sulcus is theorized to have occurred in mammals when the complete dissociation of the original somatosensory cortex from its mirror duplicate developed in placental mammals such as primates,[1] though the development did not stop there as time progressed the distinction between the two cortices grew.It then becomes a distinct invagination that lengthens towards the lateral sulcus and towards the longitudinal fissure[4] at approximately 22 to 23 weeks of gestational age.Those of male biological sex have been found to have a less convoluted (small fractal dimension) right anterior wall of the central sulcus.[11] Studies have found that when the central sulcus is larger in the left hemisphere, the individual tends to me more right hand dominant.Attention deficit hyperactivity disorder (ADHD) has been associated with sensorimotor deficits and the central sulcus divides both somatosensory and primary motor areas prompting research into how the shape of the central sulcus and ADHD may alter brain development in these individuals.[13] The morphology of the central sulcus has been suggested to play a role in individuals with the genetic condition known as Williams syndrome.[14] However, the abnormal dorsal end of the central sulcus has not been found to be linked to impaired general intelligence.