Brain. Computer artwork of a side view of a healthy human brain. At centre is one of the hemispheres of the cerebrum, which is responsible for conscious thought, emotion and voluntary movement. At the centre of the cerebrum is one of the temporal lobes, which is involved in visual processing, hearing, speech and memory. At the base of the brain is the cerebellum, which controls voluntary muscular movement and maintains posture and balance. The brainstem, which controls subconscious functions such as breathing and the regulation of heart rate, connects the brain to the spinal cord (orange).