Human brain basal ganglia, and related structures. The diencephalon gives rise to the thalamus and hypothalamus. The hindbrain also splits into two areas – the metencephalon and the myelencephalon. The metencephalon gives rise to the cerebellum and pons. The myelencephalon gives rise to the medulla oblongata. Also during the fifth week, the brain divides into repeating segments called neuromeres. These are known as rhombomeres seen in the hindbrain. A characteristic of the brain is gyrification (wrinkling of the cortex). In the womb, the cortex starts off as smooth but starts to form fissures that begin to mark out the different lobes of
Cerebellum transform sensory inputs in some sophisticated way, perhaps to compensate for changes in body posture. In fact, James M. Bower and others have argued, partly on the basis of these structures and partly on the basis of cerebellar studies, that the cerebellum itself is fundamentally a sensory structure, and that it contributes to motor control by moving the body in a way that controls the resulting sensory signals. Despite Bower's viewpoint, there is also strong evidence that the cerebellum directly influences motor output in mammals. Even the earliest anatomists were able to recognize the cerebellum by its distinctive appearance. Aristotle